Huge solar energy improvement - Nano-sized antenna arrays

Solar energy is not only the most popular energy source in the world, it is also the most abundant energy source of them all. Still, solar energy is still far behind fossil fuels in terms of primary energy consumption, mostly because of its lack of cost-effectiveness when compared with traditional energy sources (coal, oil, hydro and natural gas).

One of the latest promising technologies comes from the University of Connecticut engineering professor Brian Willis. The first tests have showed the excellent potential and this technology looks to have what it takes to vastly improve today's solar energy systems.

The basic principles of this technology that rely on incredibly small nano-sized antenna arrays that are in theory capable of capture more than 70 percent of the sun's electromagnetic radiation and simultaneously converting it into usable electric power thus greatly improving the efficiency of currently used solar cells.

With today's technology, even the most effective silicon panels are not able to collect more than 20 percent of available solar radiation, not to mention that the separate mechanisms are needed to convert the stored energy to usable electricity for the commercial power grid. This pretty much efficiency as well as quite an expensive development costs are the two major stumbling blocks to the widespread adoption of solar power as a practical replacement for traditional fossil fuels.

Theoretically promising is not anything for commercial production and scientists have lacked the technology required to construct and test because the fabrication process is extremely challenging. The nano-antennas because of their ability to both absorb and rectify solar energy from alternating current to direct current must be capable to operate at the speed of visible light and be built in such a way that their core pair of electrodes is a mere 1 or 2 nanometers apart, which is approximately 30,000 times smaller than the diameter of human hair.

Illustration of a working nanosized optical rectifying antenna or rectenna (source).

However, the potential solution for fabrication issue can perhaps be found in the selective area atomic layer deposition (ALD) that was developed by Willis. The Professor Willis developed the ALD process while teaching at the University of Delaware, and patented the technique in 2011.

As he explained it is through atomic layer deposition that scientists can finally fabricate a working nano-antenna device. In a nano-antenna, one of the two interior electrodes must have a sharp tip, similar to the point of a triangle. The trick here is getting the tip of that electrode within one or two nanometers of the opposite electrode, which is something similar to holding the point of a needle to the plane of a wall. Before the ALD came into the picture, the existing lithographic fabrication techniques were unable to create such a small space within a working electrical diode. Even when using sophisticated electronic equipment such as electron guns, the closest scientists could get was about 10 times the required separation. However, through ALD, Willis was able to precisely coat the tip of the nano-antenna with layers of individual copper atoms until a gap of about 1.5 nanometers is achieved. The process is self-limiting and stops at 1.5 nanometer separation.

The size of the gap is of vital importance because it creates an ultra-fast tunnel junction between the nano-antenna's two electrodes, which allows a maximum transfer of electricity. This gap also gives energized electrons on the nano-antenna just enough time to tunnel to the opposite electrode before their electrical current reverses and they try to go back. The triangular tip of the nano-antenna prevents electrons to reverse direction, thus capturing the energy and rectifying it to a unidirectional current.

These nano-antennas, because of their incredibly small and fast tunnel diodes, are capable of converting solar radiation in the infrared region through the extremely fast and short wavelengths of visible light, something that has never been accomplished before. The current solar panels build on silicon have a single band gap which, allows the panel to convert electromagnetic radiation efficiently at only one small portion of the solar spectrum unlike nano-antennas that are able to harvest light over the whole solar spectrum, creating maximum efficiency.

Prior to the advent of selective atomic layer deposition (ALD), it has not been possible to fabricate practical and reproducible nano-antenna arrays that can harness solar energy from the infrared through the visible and ALD is what makes the creation of these devices possible. The atomic layer deposition process is favored by science and industry because it is simple, easily reproducible, and scalable for mass production. The method being used to fabricate nano-antennas can also be used in thermoelectrics, infrared sensing and imaging, and chemical sensors.

Willis has already made the prototype device and as he says „now we're looking for ways to modify the nano-antenna so it tunes into frequencies better.“ The question whether these devices really function at this high level of efficiency is yet to be answered?’ Theoretically this is possible, but further tests in practice will tell us the rest of the story.

PV electricity generation is not that complicated

The process of generating electricity with a photovoltaic solar system is not as complicated as many people think it is. It's actually a rather simple process that consists of several different principles. The basic principle is at follows; once the sunlight hits the surface of the PV panels the electrons in the solar cells get activated. The activation of electrons means that they start to move with much bigger frequency, and in the process they start to bump into each other more frequently. This interaction between the electrons is what generates electricity.

A solar (photovoltaic) panel or module consists of large amount of individual solar cells. If we were to simplify things we could say that solar cell is primarily silicon with some circuitry. The more cells there are in a solar panel, the more electricity it can generate. A string of panels makes up an array and multiple arrays comprise a solar PV system.

If we were to divide things even further we could say that PV system is only one form of harnessing solar energy. For instance, hot-water system is used specifically to heat water while A Concentrated Solar Power system (CSP) uses mirrors to focus sunlight on water, causing it to boil producing steam, which is then used to generate electricity.

PV systems are in most cases connected to the grid with the only real exception here being people in more remote locations where a battery back-up system is often lot more practical. Two primary types of solar panels are mono-crystalline and polycrystalline.

Silicon is the primary material used in solar panels as the main active material in a solar cell, primarily because of its unique chemical properties. A silicon atom is comprised of twelve electrons on three separate 'shells' or layers. The outermost 'shell' has four electrons that are highly reactive. The outer electron shell of a silicon atom is seeking to reach of state of equilibrium by 'sharing' its electrons with other atoms. Conversely, those other atoms will share their electrons as well.

These electrons are always moving but the energy from the sun causes their rate of movement and interaction to increase. By bumping into each other more frequently they generate friction and this is what generates electrical energy. After this phase it is only a matter of channeling the current through all the wiring to the inverter. The inverter is needed to convert the electricity from direct current to alternating current because our electrical grid is not designed to handle direct current. In a grid tied system any excess current is supplied back to the grid. In off-grid PV system there is usually a battery back-up system to store excess current generated by the system for later use.

Generating electricity from the sun is a very practical way to meet our electrical demand, especially because solar panel prices have decreased by more than 70% in the last five years. This particularly applies to remote and isolated areas where using PV panels to generate electricity is far more efficient than rebuilding entire energy grid.

Solar energy potential, current issues and future role

Solar energy is form of renewable energy that receives the lion share of media coverage. There are several reasons for this with most obvious being that Sun is free and practically unlimited source of energy, for at least next five billion years. Solar technologies are constantly developing and are vastly improving its cost-effectiveness ratio as compared to other energy sources though it also has to be said that solar energy is still some way off from achieving cost parity with traditional sources of energy (fossil fuels). Solar energy technologies are usually divided on active and passive solar energy technologies. Active solar energy technologies include photovoltaics and solar thermal collectors to harness the energy from the Sun while passive solar technologies include methods such as orienting a building towards the Sun or selecting materials with favorable light dispersing properties.

Many energy experts agree that clean solar energy offers our civilization huge long-term benefits. These not only include positive impact on climate change and less pollution but also limitless source of free energy that is the most abundant of all other energy sources on our planet. Fossil fuels, as many of you already know, are finite energy sources, meaning they will eventually become exhausted, and once this starts to make toll world needs to have adequate alternatives ready, so why not give solar energy a change it most definitely deserves?

What exactly is energy from the Sun?

Sun radiates enormous amounts of energy. It has been said that our planet receives 174 petawatts (PW) of incoming solar radiation at the upper atmosphere, with 70% of this gigantic amount being absorbed by clouds, oceans and land masses. It has been estimated that the total solar energy absorbed by Earth's atmosphere, oceans and land masses is approximately 3,850,000 exajoules (EJ) per year. Energy from the Sun is essential for all life on our planet, and our planet is heavily dependent on this energy. Without solar energy there also wouldn't be photosynthesis, a base for the entire food chain on our planet. Harnessing solar energy to power our entire industry and society in general is currently a dream but in years to come this dream could well become a reality, after all this is pretty logical conclusion when you consider the total amount of available solar energy and the miniscule amount of this total number we need to power our world.

Sun radiates enormous amounts of energy.

Solar energy development – The challenges that need to be overcome

Solar energy industry is still fairly young in terms of development, and therefore still lacks the "proven technology" mark that other energy sources, most notable fossil fuels, have. The lack of maturity of solar energy sector means that efficiency is still inadequate and that the total costs are still too high, meaning that solar energy industry still has a mountain to climb in order to become cost-competitive with fossil fuels.

The prices of solar energy technologies are still relatively high but the good news is that they are also constantly declining though still not enough to compete with the costs of fossil fuels without the subsidies. High costs, lack of maturity in development, and the lack of tradition are top reasons why solar energy is still couple of decades away before achieving cost-parity with fossil fuels. Solar energy storage issue is also one of the challenges for young solar energy industry. Sun doesn't shine at night or when it is cloudy or raining so what the industry needs is an adequate solar energy storage technique that would do the job in these situations by providing reliable supply. The scientists from all over the world are currently working on solar energy storage issue and the world still eagerly awaits effective solution to this issue.

What exactly are photovoltaics?

Photovoltaic is term with which we are often bombarded with by solar energy industry. The best way to define photovoltaics would be to say that these are devices that convert sunlight into electricity by using the photoelectric effect. Solar cells are also often referred to as photovoltaic cells, and they aren't exactly the brand new technology as some people think they are. The creation of first photovoltaic cell is more than one century old as the first one was constructed by Charles Fritts in the 1880s. It also has to be said that the first significant application where solar cells showed their potential and worth was as a back-up power source to the Vanguard I satellite in 1958.

Photovoltaic cells are made of semi-conducting materials very similar to those used in computer chips. There are several different types of photovoltaic cells and it is still early to tell which one will win the commerciality race; among those that are currently mostly used are thin film, monocrystalline silicon, polycrystalline silicon, and amorphous cells.

Concentrating photovoltaics is also well known term used by global solar energy industry. Photovoltaic cells that are designed to operate with concentrated sunlight are built into concentrating collectors that use lenses to focus the sunlight onto the cells. It is fair to say that this may not be an ideal solution because the lenses must be pointed at the sun so the efficient use of concentrating collectors is really limited to location with the highest solar insolation values. However, concentrating photovoltaics are advantageous in terms of costs because they use very little expensive semi-conducting materials.

An average photovoltaic cell has an efficiency of 15%, which means that less than one-sixth of the sunlight striking the cell actually generates electricity which means that efficiency levels are in need of massive improvement in order for photovoltaics to rule the global energy market and achieve cost-parity with fossil fuels.

Current usage and conclusion

Solar energy can provide us with over 1000 times more energy than this world currently needs but despite of this enormous potential solar power is yet to reach tiny 0.03% of the world's total energy supply.

There are several answers to the question why the world isn't using more solar energy to satisfy its huge energy demand. As already said above solar energy technologies are still in the very early phase of development, which gives us an answer as to why solar power still fails to achieve efficiency comparable with fossil fuels. An average solar panel has an efficiency of around 15 percent, which means that large amount of solar energy gets wasted, and ends up like a heat instead being turned into some form of useful energy. The intermittency is also one of the burning issues that solar energy sector will have to find the solution for in the form of adequate solar energy storage method. In fact, making solar energy panels lot more effective and far cheaper is what global solar energy industry needs to dominate. The science will have to play its part, and so will the politics because without politics science cannot obtain the necessary funds needed for further research and important new discoveries. Luckily, many of the world countries favor solar energy and the sector has become well subsidized in the recent years which resulted in many favorable policies for future solar energy development in much of the world. It 's no doubt that solar energy industry will continue to develop and further improve, and if all goes according to the plan, in one moment of the time, solar energy will become the dominant form of energy on our planet. It's difficult to predict when exactly will this moment come, but there are very few of those who doubt future leading role on solar energy industry on global energy market.

Thinner solar cells could be the next big thing

Most technological innovations aimed at improving solar cells have focused primarily on increasing the efficiency of their energy conversion, or on lowering the cost of manufacturing. However, there is another approach coming from MIT researchers that are aiming to produce the thinnest and most lightweight solar panels possible.

These extra thin solar panels have the potential to surpass any substance other than reactor-grade uranium in terms of energy produced per pound of material. The MIT researchers also stated that they could be made from stacked sheets of one-molecule-thick materials such as graphene.

Using two layers of one-molecule-thick materials it is possible to create solar cells with 1 to 2 percent efficiency in converting sunlight to electricity, That's pretty low compared to the 15 to 20 percent efficiency of standard silicon solar cells but the plus side is that is being achieved using material that is thousands of times thinner and lighter than tissue paper. The two-layer solar cell is only 1 nano-meter thick, while on the other hand conventional silicon solar cells are usually hundreds of thousands of times that. The stacking of several of these two-dimensional layers could boost the efficiency significantly thus being able to compete with conventional technologies.

There are certain applications where weight is a crucial factor –this include spacecraft, aviation or for use in remote areas of the developing world where transportation costs are significant, and in these cases using these lightweight cells could be far more beneficial than sticking with conventional technology.

If we were to measure things pound for pound these new solar cells would produce up to 1,000 times more power than conventional photovoltaics. Being so thin makes it advantageous in shipping, but it also makes ease of mounting solar panels and when you consider that half of the costs of today's solar panels are in support structures, installation, wiring and control systems, going for these cells could significantly reduce the total costs.

The fact that cannot be ignored either is that the material itself is much less expensive than the highly purified silicon used for standard solar cells and since the sheets are extra thin, they require only minuscule amounts of the raw materials.

The additional advantage of these materials is their long-term stability, even in open air, while other solar-cell materials must often be protected under heavy and expensive layers of glass. These materials have proven to be quite durable as they are stable in air, under ultraviolet light, and even in moisture.

The researchers are yet to turn computer models into actual production but the potential is certainly there. Perhaps this is the first step to a new trend in solar energy industry, creation of extra thin solar cells.

Top five renewable energy sources

Renewable energy has started making headlines with many energy experts looking at various renewable energy sources such as solar energy, wind energy, geothermal energy, hydro power, and biomass. Renewable energy is very important because it offers alternative to using fossil fuels, not just in terms of reducing harmful greenhouse gas emissions but also to replace depleting oil, coal and natural gas. Renewable energy also improves our energy security and our energy independence, and is extremely abundant, practically limitless, meaning that the future will no doubt belong to renewable energy.

SOLAR ENERGY

Solar energy is the most abundant energy source on our planet but the world currently uses a tiny fraction of the totally available solar energy. Solar energy technologies are still connected with high costs, and do not offer satisfactory efficiency, though things are certainly improving very fast.

Solar energy is environmentally friendly renewable source of energy. Harnessing solar energy doesn't result in increase of harmful CO₂ emissions. The other advantage of solar energy is that the Sun is virtually unlimited source of energy that could supply with ease our current as well as the future energy demand, even with the predicted global population growth, as for instance covering just 4% of the world's desert area with solar panels would be enough to supply all of the world's electricity.

The downside of solar energy is that solar panels are still connected with relatively high costs, there are many ongoing solar researchers and hopefully science will soon find solutions to improve economics and efficiency of solar power technologies.

In 2012, solar energy accounted for less than 0.03% of the world's total energy supply, which is way too little, given its enormous potential. Despite this small number solar energy sector is constantly growing, and solar energy industry is one of the fastest growing industries in the world. The largest photovoltaic market in the world is still Germany.

Generally speaking, solar power plants have positive environmental impact. Harnessing solar energy doesn't contribute to climate change, acid rains or any form of pollution. This however doesn't mean there are no downsides to solar power plants, for instance manufacturing solar panels involves some toxic materials and the fact that huge solar power require lot of land for construction, and lot of water for cooling purposes.

Solar power plant.

WIND ENERGY

Wind energy has very long tradition as people were using wind energy for more than 5000 years to propel sailboats and sailing ships. These days wind energy is mostly used to generate electricity by using wind turbines. Wind power is one of the fastest growing renewable energy markets, even despite the stagnation in recent years, after losing its popularity to solar energy. Wind farms are no longer being built only on land but also offshore and offshore wind energy could in years to come become dominant way of harnessing wind energy.

Wind energy is ecologically acceptable renewable energy source that does not contribute to climate change or air pollution. Wind turbine prices are constantly decreasing and wind is certainly becoming cost-competitive on global energy market, as it currently represents one of the few renewable energy sources that could actually compete with fossil fuels in terms of economics.

Wind energy is intermittent energy source, and in times when wind doesn't blow we need another backup energy option to ensure constant energy supply for reliable power delivery. Large wind turbines with huge blades can sometimes lead to bird deaths if not equipped with radars. Sometimes it is difficult to integrate wind turbines into existing environment because they can disrupt visual effect of certain landscape.

Wind farms represent a group of interconnected wind turbines on one location which is used for production of electricity. At this moment, the world's largest wind farm is The Roscoe Wind Farm, with the output of 780 MW, in the US state of Texas.

Wind energy has overall positive environmental impact since there are no emissions involved. Certain environmental drawbacks are still present such as the fact that large, fast rotating blades can kill many birds if not equipped with radar, large wind turbines can also create noise pollution which can have negative effect on wildlife in nearby area.

Wind power plant.

GEOTHERMAL ENERGY

Geothermal energy also has relatively long history of use and refers to power extracted from heat stored in the Earth. This heat comes from the radioactive decay of various elements beneath the Earth's surface, volcanic activity, and also from solar energy that was absorbed at the surface. People were first using geothermal energy for bathing, though today geothermal energy is mostly used to generate electricity, though there also some countries that use geothermal energy for heating purposes in form of geothermal heating.

Geothermal energy is renewable energy source that cannot be depleted since earth is in constant state of producing heat (though there can be a factor of temporary local depletion), and it does not produce harmful carbon emissions nor it contributes to air pollution like fossil fuels (coal, oil, and natural gas do). Geothermal energy is clean, cost effective, reliable, sustainable, and environmentally friendly source of energy. Unlike solar and wind energy geothermal energy isn't intermittent energy source and is thus very reliable in terms of supply and delivery.

Geothermal power plants are very expensive to be built costing twice as much compared to coal and natural gas fired plants. High construction and drilling costs are the main reason why geothermal energy is being harnessed in only 24 countries of the world, as it is only being economically acceptable in areas with suitable amount of hot rocks at just the right depth for drilling. Once the drilling technologies become more technologically advanced geothermal energy will likely become much more competitive to fossil fuels.

Three basic types of geothermal power plants are: 1.dry steam plants where steam is piped directly from a geothermal reservoir to turn the generator turbines. 2. flash steam plants that takes the high-pressured hot water from deep inside the Earth and convert it to steam to turn the generator turbines. 3. binary cycle power plants that transfer the heat from geothermal hot water to another liquid, and afterwards the second liquid is turned into the steam that turns the generator turbines.

Geothermal energy is overall environmentally friendly source of energy. Existing geothermal electric plants emit an average of 122 kilograms (269 lb) of CO2 per megawatt-hour of electricity, which represents an amount negligible compared to fossil fuel fired plants. Harnessing geothermal energy has minimal land and freshwater requirements which are drawbacks of solar energy. The only potential environmental threat comes from fluids drawn from the deep earth as they carry a mixture of gases, such as carbon dioxide (CO2), hydrogen sulfide (H2S), methane (CH4) and ammonia which can (if not treated properly) add to global warming, air pollution, and acid rain.

Geothermal power plant.

HYDROPOWER

Hydropower is renewable energy source that has very long history of use, mostly in form of waterwheels and mills. Hydropower is today the most widely spread renewable energy source on global scale supplying around 20% of total global electricity.

Hydropower is renewable energy source that doesn't pollute our planet with harmful greenhouse gas emissions like this is the case with oil, coal and natural gas. Hydropower plants have long lifespan and relatively low maintenance costs since modern technology has enabled that almost everything is automated. Hydropower is very efficient source of energy, and doesn't suffer from intermittency like solar and wind do.

As already mentioned above, hydropower is still the most important renewable energy source on global scale, accounting for approximately 20% of the world's electricity. China currently leads the way in hydroelectricity generation, mostly because of its massive hydropower projects such as Three Gorges Dam.

The largest hydroelectric power plant in the world is Three Gorges Dam in China, with the capacity of 22.5 GW, the second ranked is Itaipu Dam, located between Brazil and Paraguay with the capacity of 14 GW.

The massive hydroelectric power plants can have negative impact on environment if not thoroughly planned and carefully constructed as this was the case with the construction of Three Gorges Dam that led to massive flooding and other negative environmental consequences.

Hydro power plant.

BIOMASS 

Biomass is renewable energy source that refers to biological material deriving from living, or recently living organisms such as wood, waste or biofuels. The five different energy resources from which the biomass derives are wood, waste, garbage, landfill gases, and alcohol fuels.

Biomass is abundant and widely spread source of energy that can be found in almost every corner of the world. Biomass is often said to be carbon neutral energy option, though there are many ongoing studies that still argue whether biomass is really carbon neutral or not. Biomass is also connected with CO2 emissions like fossil fuels are, though it does not contribute to global warming like fossil fuels do because burning of biomass which releases CO2 emissions is said to practically balance the CO2 absorbed by the plants during its growth. Biomass is becoming increasingly popular energy source on global scale, with many countries opening new biomass facilities. Wood is still the most popular form of biomass on global level, though there are many ongoing researches that aim to find the adequate solutions to turn waste and garbage into useful form of energy.

Biomass is said to satisfy today around 4% of US energy needs with more than half of this referring to biomass form using wood. The 2011 US study said that the currently existing biomass power generating industry in the United States has the capacity for around 11,000 MW.

The largest biomass power plant in United States is The New Hope Power Partnership, Florida with the capacity of 140 MW. Biomass power plant size is often driven by biomass availability in close proximity as transport costs of the fuel play a key factor in the plant's economics.

Since wood is the most common form of biomass, unsustainable biomass production could also lead to deforestation which together with the fact that biomass releases CO2 emissions represents environmental drawback of using more biomass.

Biomass power plant.

Solar power - US vs China

Solar energy industry is currently the fastest growing industry in the world, and the most rapidly changing renewable energy sector, where all big countries of the world tend to have their say as much as possible. The economic rivalry between The United States and China has also spread on solar power, and there is an ongoing battle for supremacy in this energy market between these two countries

It has been reported that the United States will likely try to work out a deal that would end ongoing disputes over trade in solar energy products. The European Union already threaten China by saying it would hit back at Chinese solar energy manufacturers for dumping their solar energy products in the European market.

The US did the similar move by the U.S. Commerce Department last year and a senior White House official testified last week that trade policies between countries can only work if they're fair to both countries. The China and the United States are still debating how to best accommodate the other's claims to power, though it seems that the White House may have a few aces up its sleeve to resolve issues related to global renewable energy and trade issues, especially in relation with EU energy policies.

European Trade Commissioner Karel De Gucht has recently complained that Chinese solar panels were sold on the European market below cost on dumping prices which was giving Chinese manufacturers an unfair advantage over the European solar manufacturing companies. In order to counterattack these dumping prices, the EU announced it would impose an 11 percent duty on Chinese solar panel imports. If China still fails to reach a compromise that duty could increase to more than 47 percent by the August.

It is a well known fact that China dominates the global energy market in terms of production of solar panels. The total exports of Chinese solar panels to the European market in 2011, the last year for which information is available, totaled more than $27 billion dollars. Last year, the U.S. Commerce Department targeted Chinese solar manufactures in one of the largest anti-dumping initiatives in U.S. history to protect its solar energy market.  In the United States, China is major player by dominating the solar cell market, with about $3.1 billion worth of goods being imported in 2012.

The Chinese government considers the renewable energy sector, solar power in particular, to be a vital component of its domination in clean energy race. The battle for supremacy on global clean energy market is becoming tenser with each new day, and there still doesn't seem to be the will between all the parties to reach a satisfying agreement as all involved tend to achieve the best possible position on global renewable energy map. Whether there is enough room for both China and United States on top of the hill in terms of renewable energy still remains to be seen. The new trade laws will certainly set the tone, at least short-term speaking.

Quick introduction to energy sources

The energy can take many different forms and this is the main reason why there is a variety of different energy sources. The first thing you need to know about energy sources is the fact that fossil fuels, namely oil, coal and natural gas are still dominant sources of energy, despite the growing popularity of renewable energy sources.

There are two main differences between renewable energy sources and fossil fuels. First of all renewable energy sources are as their name suggests renewable, meaning that they can be constantly replenished unlike fossil fuels that are finite energy resources that will eventually become exhausted. The other difference refers to environmental impact where renewable energy sources do negligible environmental damage when compared with fossil fuels and the fact that the burning of fossil fuels is the main contributor to climate change phenomenon.

The renewable energy sources list includes these energy sources: solar energy, wind energy, hydropower, geothermal energy and biomass. Hydropower is the most widely used form of renewable energy because of its very long history.

Solar and wind energy are the most popular renewable energy sources. Solar energy is the most abundant form of energy available on our planet. The main reason why we don't use more of solar energy is because solar panels and other solar technologies are still connected with significant costs, and people do not want to pay higher energy bills, even if this means helping our environment.

Wind energy has more acceptable costs compared to solar energy though it is still far from being able to challenge the dominance of fossil fuels in terms of electricity generation. Wind energy and solar energy are not suited for all areas because they require plenty of wind/sunshine throughout the year.

Geothermal energy on the other hand is available 24-7 because it refers to heat within the Earth's core. However, considering the current technological level of geothermal drilling, geothermal power plants are economically viable only in areas near the tectonic plate boundaries where drilling demands aren't that great.
Biomass as an energy source has excellent potential because biomass material is available in all corners of the world. However, there have bee fears, that using more land for biomass production (instead of growing food crops) would lead to more hunger of the world so biomass as an energy option is still connected with significant level of controversy.

It is very realistically to accept that fossil fuels will remain dominant energy sources throughout this century. The share of renewable energy sources will no doubt significantly increase over the years but fossil fuels should still have the edge because the transition to renewable energy sources doesn't go as fast as some people have expected.

The downside of this prolonged dependence on fossil fuels is big damage to our environment, and the strengthening of the climate change impact.

Hybrid solar-gas power plants

Natural gas is becoming increasingly popular energy option because of its recent low prices, mostly due to the recent shale gas discoveries. In this sense, there are many ongoing talks about ageing coal power plants to be replaced by new natural gas fired power plants, mostly because natural gas fired power plants emit significantly less greenhouse gases as compared to coal fired ones.

The further reductions in natural gas fired power plants can be achieved by involving solar energy in the whole story. The latest study by the Energy's Pacific Northwest National Laboratory has proved that natural gas fired power plants can use about 20 percent less fuel when the sun is shining by injecting solar energy into natural gas with a new system that converts natural gas and sunlight into a more energy-rich fuel called syngas, which power plants can burn to make electricity.

What this means is that by using this new system, the existing power plants would use less natural gas to produce the same amount of electricity they already make and the another benefit is that at the same time, the system lowers a plant's greenhouse gas emissions at a cost that is said to be competitive with the traditional fossil fuel power.

The United States is becoming increasingly reliant on inexpensive natural gas for energy, and this system can have its practical use in reducing the carbon footprint of power generation. The recent DOE estimates say that natural gas will make up 27 percent of the nation's electricity by 2020 and making it cleaner would certainly account for much greener economy. These new systems would be best suited for power plants located in areas with plenty of sunshine such as the American Southwest.

By installing this new system in front of natural gas power plants turns these plants into hybrid solar-gas power plants. The system uses solar heat to convert natural gas into syngas which is a fuel that contains hydrogen and carbon monoxide. The generated syngas has significantly higher energy content, meaning that a power plant equipped with this system needs around 20 percent less natural gas to produce the same amount of electricity.

This reduced fuel usage is made possible with concentrating solar power, which uses a reflecting surface to concentrate the sun's rays like a magnifying glass. The tested system used a mirrored parabolic antenna to direct sunbeams to a central point, where a specially developed device absorbs the solar heat in order to generate syngas.

The next step for researchers is to keep the system's overall cost low enough so that the electricity produced by a natural gas power plant equipped with the system would cost no more than 6 cents per kilowatt-hour by 2020. Achieving this price would make hybrid solar-gas power plants lot more competitive with conventional, fossil fuel-burning power plants while in the same time reducing the total amount of greenhouse gas emissions.

Solar energy industry and solar energy jobs

Solar energy has experienced a remarkable growth over the last decade, in fact, solar energy industry is today one of the fastest growing industries in the world. The growth in installed solar power capacity has of course been accompanied by the creation of new green jobs within the solar energy industry. Solar energy industry does not only employ scientists and researchers who are constantly looking for solutions that would allow the creation of cheap and efficient solar cells (the holy grail of solar energy industry) but also people that know how to build solar panels, people to sell and deliver solar panels, as well as the usual jobs such as accountants or managers. So there are really plenty of different options to choose from and find the job within the solar energy industry.

People who are looking for more specialized knowledge about solar power should look for solar power programs and courses that are becoming increasingly popular on many universities across the country. Solar industry is constantly growing, not only in the United States but also on global scale, and therefore there are many different universities that have started to offer degrees in solar power studies.

What is the best way to find the solar energy job that is most suited to you and your needs? The good starting point would be to introduce yourself to as many information about solar power as possible, and see which solar energy jobs would require the least adapting from your part. For instance, if you already have decent technical knowledge then the solar panels installer job may end up being the perfect job for you, especially since solar panels are becoming popular clean energy option for many homeowners, and so the solar companies are in the constant need of finding the qualified personnel to satisfy the growing demand for solar panels.

Together with specialized programs, available at many universities across the country, different solar workshops and events also teach specialized skills that are often necessary to find the highly paid jobs within the solar power industry.

The thing that interests many people is of course the salary. Let us use the solar panel installer job as an example so you can get clearer image about salaries within the solar energy industry. In United States, the average salary for solar power installer is around $45,000 per year. This certainly does not sound too bad, especially if you consider that training programs for this job can last as short as six months. Solar power engineer, for instance, can earn more than $90,000 per year.

Obama has already announced further government funding for new solar power projects, meaning that solar power industry will no doubt be looking for new jobs. Energy analysts have calculated that these new funds will create over 1500 permanent solar energy jobs.

Solar water heaters facts

Solar water heaters are devices and systems which use solar energy to heat water. Solar water heating or solar hot water systems comprise several innovations and many mature renewable energy technologies that have been well established for many years.

Solar water heating (SWH) systems include storage tanks and solar collectors in which water is heated. There are two types of solar water heating systems: active, which have circulating pumps and controls, and passive, which do not have pumps. Passive solar water heating systems are typically less expensive than active systems, but they're usually not as efficient. However, passive systems can be more reliable and may last longer.

Solar water heating systems are designed to deliver hot water for most of the year. However, in winter there sometimes may not be sufficient solar heat gain to deliver sufficient hot water. On cloudy days, if it is for a day or two, one still get warm water as water gets heated due to diffused radiation available in the atmosphere. The system, however, is either connected to an electric geyser in the house or an electric al backup is provided in the storage tank of the system which is switched on when water is not sufficiently hot.

SWH systems reduce energy spending: sunlight is free, so once system is paid for the initial installation hot water costs will be reduced. Also, this system will reduce carbon footprint: solar hot water is a green, renewable heating system and will reduce carbon dioxide emissions when installed.

Maintenance costs for solar water heating systems are generally very low. Most solar water heating systems come with a five-year or ten-year warranty and require little maintenance. In a well maintained system, pumps can last for more than ten years.

In order to heat water using solar energy, a collector, often fastened to a roof or a wall facing the sun, heats working fluid that is either pumped (active system) or driven by natural convection (passive system) through it. The collector could be made of a simple glass-topped insulated box with a flat solar absorber made of sheet metal, attached to copper heat exchanger pipes and dark-colored, or a set of metal tubes surrounded by an evacuated (near vacuum) glass cylinder.

There are records of solar collectors in the United States dating back to before 1900, comprising a black-painted tank mounted on a roof. In 1896 Clarence Kemp of Baltimore, USA enclosed a tank in a wooden box, thus creating the first 'batch water heater' as they are known today.

When designing solar water heaters two big issues must be addressed: freeze protection and overheat protection. Freeze protection measures prevent damage to the system due to the expansion of freezing transfer fluid. Drainback systems drain the transfer fluid from the system when the pump stops. Many indirect systems use antifreeze in the heat transfer fluid. When no hot water has been used for a day or two, the fluid in the collectors and storage can reach very high temperatures in all systems except for those of the drainback variety.

Home solar water heating systems cost an affordable $1,500 to $3,500, and pay for themselves in four to eight years. This can be very good investment in current climate of rising energy prices.

Passive solar gives many affordable options

Solar energy is certainly the most popular clean energy source but is it also the best? People are becoming more interested into clean energy choices because our continued use of fossil fuels is leading to major environmental issues that threaten our future well-being, such as climate change.

There is a variety of different clean energy choices available today many of which are supported with tax benefits and other financial incentives from governments and local utilities which can decrease the costs tremendously. Throughout this article are the most important reasons why using passive solar is one of the wisest clean energy options.

Many people are not aware that they can begin to use solar without spending a penny, in fact, one will save money. This can be achieved by making passive solar choices, for instance by simply allowing the sun to pour in your windows in winter to help you heat and adding heavy thermal curtains in the summer to prevent overheating, can reduce your electric bill and is a viable way to take advantage of passive solar energy.

There are several inexpensive standalone solar technologies that give you an opportunity to make good use of the energy of the sun and save money in the process. Such is, for instance, a standalone outdoor solar lighting system that can be used to make your yard safer at night while saving you money on your electric bill.

You can utilize solar energy for various purposes in your yard and garden. As an example solar pool heaters and lights that are both very affordable as well as efficient. One can also purchase a floating solar heater for your pool that would simply give your existing system an assist. This sort of heater can also be used for specific purposes such as in garden ponds if the type of fish you keep cannot tolerate the winter temperatures in your area.

This concept was first studied by Socrates, a classical Greek philosopher, almost 2500 years ago. In early literature this concept is known as "Socratic House". "Socratic House" is a hypothetical description of energy efficient house. The essence of Socrates' studies was influence of the Sun movement to the shape, form and construction of a building.

People that are planning a new home can make tremendous use of passive solar power. There are many architects who know how to make the most use of energy efficient materials and window placement to help you heat and cool your home with the very least possible use of fossil fuels. Even though this type of construction is a bit more expensive at the outset, the amount of money you save in the long run will make your investment well worth it, because if you eventually decide to sell your estate it will worth more than the ones without this construction. Add to this many states and local governments that offer grants, rebates or other incentives and passive solar energy will certainly seem like a profitable option, particularly on the long run.

For any purpose that you do not have to run electrical wiring you can save a significant amount of money and you can improve your energy independence in the process. When choosing the site for your new home or getaway, look for property that has southern exposure and good solar insolation values in order to make your solar energy systems as cost-effective as possible.

Choosing solar is indeed a wise option, not just from environmental but also from economic point of view. A typical solar energy system does not lose much in its efficiency for 25-30 years, and there is very little if no maintenance at all.

Things solar and wind need to improve

Solar and wind energy are very popular these days. Not only are these two renewable energy sources environmentally friendly and can help against climate change, they also have excellent potential and can lead to creation of many new jobs for many people all over the world.

However, there are still many things that need to be improved prior to replacing fossil fuels fired power plants with solar panels and wind turbines. This however, should not come as a surprise because fossil fuels have long tradition and history of use behind them while solar and wind power technologies have only started their development few decades ago, and are yet to mature from the technological point of view.

First of all, wind and solar power technologies need to become cheaper. Even despite their surge in popularity wind turbines and solar panels still present a rather costly energy option for many homeowners, many of which are still not willing to pay higher price, even despite the positive environmental impact in form of less greenhouse gas emissions.

Solar panels and wind turbines also need to become lot more efficient because lot of energy gets wasted in the process of their conversion to electricity. The average solar panels reach efficiency levels of 15-18% and the situation is not much better with wind turbines either. The science is working hard to create more efficient solar panels and wind turbines but there is sadly still not a commercially viable solution that would solve this efficiency issue.

Contrary to conventional scientific wisdom, the key to solar cell efficiency is not absorbing more photons but emitting more photons. (Image courtesy of DOE NREL).

Since solar and wind are not available all day long (sun does not shine all day long and wind does not blow all the time) they belong to so called „intermittent“ energy sources, meaning they require extra energy storage solution in order to reliably deliver power 24-7. The science is still looking for cheap and highly efficient energy storage solutions for these two sources, and though there have been many proposed solutions none of them has reached the commercial level that could provide cost-competitiveness on global scale.

Solar power plants require lot of water for cooling purposes and this is also something that future solar power technologies will have to find better solution for, especially because water could soon become very scarce resource in many parts of the world.

Wind turbines can kill birds if not equipped with adequate radars and can also create noise pollution in nearby area.

As you can see from the facts stated above wind and solar are far from being the perfect energy sources, at least at the current stage of their technological development. Still, they are definitely wiser option when compared to currently dominant fossil fuels, because many environmental issues (such as climate change) that present big threat to the future of humanity are directly connected with fossil fuels burning.

California expands its renewable energy market

In the last ten years or so the state of California has been recognized on nation-wide level as the leader in renewable energy development. Judging by the latest plans the state looks likely to keep this lead for many years to come, especially after California's Governor Jerry Brown signed the renewable energy bill, which requires that 33 percent of the state’s electricity comes from renewable energy sources by 2020. This is a kind of renewable energy portfolio standard that clean energy investors like, and California will likely attract the lion's share of total nationwide renewable energy investment in years to come.

In order to achieve this target California has already announced plans to increase its renewable energy capacity by adding approximately another 9,000 megawatts (MW) of renewable energy by 2020, with the main emphasis on solar panels, wind turbines and geothermal power plants.

Why is California planning yet another big renewable energy expansion? For starters, California wants to further enhance its leadership position in nationwide renewable energy development, and second California is well aware that strong renewable energy development attracts new investments which create new renewable energy jobs as well as other benefits that will move state's economy forward. California is also having trouble with air pollution in many of its urban areas (Los Angeles), and more renewable energy sources such as solar and wind would no doubt reduce the impact of air pollution in many of its cities, particularly when combined with initiative for more hybrid and electric cars.


The stimulating renewable energy legislation is the key to develop a stable renewable energy business and create friendly environment for new investments. Renewable energy investors want long-term safety before making their business moves, and California is providing them exactly that.

If we look at California's renewable energy legislation more closely we can see that California needs to meet a 20-percent of electricity target from renewable energy sources by December 31, 2013, a 25-percent by the end of 2016, before achieving the final target of 33-percent of renewable electricity by the end of 2020.

This rapid renewable energy development in California is good for the entire United States because California is yet again showing the path other U.S. states could follow. If U.S. wants to be competitive with China in clean energy race these types of renewable energy mandatory targets will have to become the rule, and not just the exception.

California is currently the nation's leader in installed solar and geothermal power capacity. Wind power development isn’t looking bad either. All prerequisites are there, and California can already start looking forward to a clean energy future.

Energy history facts

From ancient times people use various energy sources. Geothermal energy were used for springs and heating, hydro and wind energy were used for mills, sailing, water pumps and other mechanical devices, solar energy was used for heating, biomass and coal were used for heating, illumination, cooking, and so on.  For example, nearly 2000 years ago the Greeks used water wheels to grind wheat into flour.

Steam engines were first serious “modern” power source in the world. Steam engines were mostly powered by biomass and coal. The first commercial steam-powered engine device was a water pump, developed in 1698 by Thomas Savery. It used a vacuum to raise water from below, then used steam pressure to raise it higher.

Edwin Drake's 1859 well near Titusville, Pennsylvania, is popularly considered the first modern crude oil well. In the 1840s, the process to distill kerosene from crude oil was invented by James Young in Scotland and the first refinery was built by Ignacy Łukasiewicz, providing a cheaper alternative to whale oil.

The world's first power plant consisted of 24 dynamo electric generators which were driven by a steam engine. It was built by Sigmund Schuckert in the Bavarian town of Ettal (Germany) and went into operation in 1878. Power plant is industrial facility for the generation of electric power.

The first commercial power plant in the United States using three-phase alternating current was at the Mill Creek No. 1 Hydroelectric Plant near Redlands, California, in 1893 designed by Almirian Decker.

In 1878 the world's first hydroelectric power scheme was developed at Cragside in Northumberland, England by William George Armstrong. It was used to power a single arc lamp in his art gallery.

The first major hydro-electric power plants were built by Nikola Tesla and George Westinghouse in 1895 on Niagara Falls (USA). These Power Plants practically started the electrification of the world.

In 1911 the world's first commercial geothermal power plant was built in Larderello, Italy. Experimental generators were built in Beppu, Japan and the Geysers, California, in the 1920s, but Italy was the world's only industrial producer of geothermal electricity until 1958.

Photoelectric effect was first observed 1839 by Edmond Becquerel, a physicist from France. In year 1876 Adams and Day observed the photovoltaic effect in solid selenium.  Modern solar cell was discovered in 1954. The first 1 MWP solar park was built by Arco Solar at Lugo near Hesperia, California at the end of 1982, followed in 1984 by a 5.6 MWP installation in Carrizo Plain.

On June 27, 1954, the USSR's Obninsk Nuclear Power Plant became the world's first nuclear power plant to generate electricity for a power grid, and produced around 5 megawatts of electric power. Obninsk is in today’s Russia.

About 500 B.C. the Chinese discovered the potential of natural gas. Finding places where gas was seeping to the surface, the Chinese formed crude pipelines out of bamboo shoots to transport the gas, where it was used to boil sea water, separating the salt and making it drinkable. Britain was the first country to commercialize the use of natural gas. Around 1785, natural gas produced from coal was used to light houses, as well as streetlights.

Opened on the 26th November 1966, the Rance Tidal Power Station is the world's first tidal power station and also the world's second biggest tidal power station. The facility is located on the estuary of the Rance River, in Brittany, France.

An early application of wave power was a device constructed around 1910 by Bochaux-Praceique to light and power his house at Royan, near Bordeaux in France. In 2008, the first experimental wave farm was opened in Portugal, at the Aguçadoura Wave Park.

Italy - One of renewable energy leaders

Current situation with renewable energy in EU is looking exceptionally good, and Italy is no exception, in fact the Apennine peninsula country has in the last couple of years become one of the European clean energy leaders. According to the official government figures Italy is well on the track to meet its EU target of generating 26 percent of energy from renewable energy sources by 2020 since currently renewable energy satisfies more than 20% of Italy's energy demand.

The country's renewable energy capacity increased significantly in 2011 to the total amount of 41,352MW at the end of the year. Hydroelectricity is still the most important renewable energy source though the wind power is looking better than ever, and wind power is currently the second largest renewable energy source in the country (in 2009 alone Italy's wind energy capacity has increased by nearly 40 percent). At the end of 2009 Italy's total wind power capacity was around 4,850 MW. Most new wind farms were installed in Sicily, Puglia and Calabria.

According to the Italian Wind Energy Association (ANEV) around 6TWh of electricity were produced by wind energy in 2009. At the end of 2011, the country passed 6000 MW mark in installed wind power capacity, and is currently sixth largest wind energy producer in the world. Though wind power development is looking exceptionally good there are still some things that need to be improved, for instance Italy still suffers from inadequate grid infrastructure because the current capacity of grid is too low, and Italy's old-fashioned 150kV lines are incapable to dispatch all the power produced by the wind farms which has lead to some wind farms operating at 30% less than their normal capacity.

Solar power is also looking good, and this is mostly the result of generous incentives for solar power that have attracted many solar companies in Italy. Thanks to these favorable incentives Italy has now become a world's second largest photovoltaic market, behind the Germany. At current pace Italy is adding around 150 MW of solar capacity per month, around three times more than US, and Italy has even managed to surpass the US in total installed solar capacity in the first quarter of this year. California, the leading US state in installed solar power capacity, is currently adding around 20 MW of solar capacity per month, and for comparison Italy is three-fourths the size of California. By the end of 2010 Italy's total solar power capacity accounted for more than 2500 MW while at the end of 2011, total installed solar power capacity in Italy was 12,750 MW, which is quite an accomplishment, and Italy has certainly become one of the global solar energy leaders and of the largest photovoltaic markets in the world.

Italy also has volcanically active areas, like Larderello in Tuscany in central Italy. Those places are perfect for geothermal power production. Geothermal power accounts for about 1.7% of the total electric energy production in Italy and is about 7% of the total renewable energy produced in 2010. The total energy from geothermal sources was 5,376 GWh in 2010. Italy is the fifth country by geothermal installed capacity.

As said before, renewable energy is not only looking really good in Italy but also in entire EU, and vast majority of EU states are on track to meet their renewable energy targets, which should in the end result in 20 percent of European energy coming from renewable energy by 2020.

Renewable electricity accounted for the 24.5% of all electric energy produced in Italy in 2011. Italy is today one of the most significant renewable energy markets in the world, even despite the recession that is still taking heavy toll in the country.

Solar and wind – Current status facts

Solar energy is almost limitless source of renewable energy in our planet. The scientists have calculated that the total amount of solar energy absorbed by our planet is approximately 3,850,000 exajoules (EJ) per year. What this means is that solar energy really has enormous potential, and that covering only 4% of the world's deserts with solar panels would be enough to satisfy all of the world's electricity demand.

Solar power, despite having this enormous potential is still far behind fossil fuels in terms of energy consumption. This is mostly because solar energy is still connected with relatively high costs, even despite the recent decline in prices of solar power technologies. For instance, solar energy (at the beginning of the 2010) had the average price of 18 cents per kilowatt hour, approximately three times more expensive than the price of coal and natural gas.

Together with decreasing the costs solar power technologies will also have to improve efficiency because an average photovoltaic cell has an efficiency of only 15%. Best modern solar cells on the market have efficiency of only about 24%. This means that plenty of available sunlight absorbed by solar panels gets wasted in the process (reflection, heat).

Wind and solar power put together is clean and sustainable energy solution.

Despite these significant disadvantages the global solar energy demand has grown at about 30% per year over the past 15 years and photovoltaic production has been growing by more than 20 percent each year since 2002. On global level, solar energy industry is currently the fastest growing energy industry in the world. The world's largest photovoltaic markets are at this moment United States and Germany, though China is also rapidly adding more solar power capacity to its grid.

Wind energy is currently the second fastest growing renewable energy industry in the world, behind solar. The total energy potential of wind power on land and near-shore is estimated to be at around 72 TW. So much available wind is more than enough to satisfy for over five times the current worldwide energy consumption.

Worldwide wind energy production at the end of 2010 was 430 TWh, which is about 2.5% of the worldwide electricity usage. In 2010 global wind power sector experienced a growth rate of 23.6 %, the lowest growth rate since 2004, mostly because of the major decrease in new wind farm installations in United States. The U.S. wind energy sector is still experiencing this stagnation because of uncertainties whether the wind energy tax credit that is set to expire at the end of 2012, will be prolonged or not.

The main driving force that pushes wind energy forward is China. China is currently the world's largest wind energy producer, and in 2010 China accounted for more than 50 % of the world market for new wind turbines. The largest wind market in Europe is Germany followed by Spain.

On global level, wind energy industry currently employs more than 700,000 people. Many energy experts believe that global wind energy industry will soon shift its focus on offshore wind energy projects because of the great potential and more frequent strong winds. U.K. currently leads the way in offshore wind energy race with the only real competition coming from China as Chinese are seriously considering plans for major offshore wind energy expansion, similar to what they have achieved with wind projects on land.

Solar power plant with mirrors – Florida example

The largest solar power plant in the United States is located in California's Mojave Desert and is owned by Florida Power & Light Co (FPL). Florida Power & Light Co has not stopped on just one project and has also constructed large solar power plant at the Martin Next Generation Solar Energy Center in Indiantown, the one that is now the second largest solar power plant in the world, with the capacity to generate electricity for around 11,000 homes. The precise location of this solar power plant is in western Martin County, Florida, just north of Indiantown.

What is special about this solar power plant? Solar facilities that use this principle have mirrors to generate heat, heat then produces steam, and afterwards steam spins turbines to generate electricity. Since Florida has pretty regular afternoon rain clouds throughout much of the year, there have been doubts about the effectiveness of this principle, and this is the reason why all other solar power plants built in Florida convert sunlight directly into electricity using photovoltaic panels, which produce a charge even on cloudy days (though a reduced one).

The main difference with this solar power plant is the fact that this plant was built on a campus near Lake Okeechobee, an area already equipped with 13 generators powered by oil and natural gas. Constructors have therefore used a different approach as they have combined steam from the solar plant with the steam produced with the heat exhaust from four natural-gas plants to spin an existing generator.

This combination is what gives this project feasibility because the utility won't have to spend millions of dollars building a generator for the solar plant. However, cloudy days still pose a certain issue because during partly cloudy days some of the plant's mirrors reflect full sunlight while others are shaded. Plant engineers definitely want to avoid alternating pulses of cooler and hotter steam arriving at an electrical generator that runs most efficiently, and they are already thinking about possible solutions for this issue.

So, Martin Next Generation Solar Energy Center is a hybrid, 75MW, solar energy plant. The solar plant is a component of the 3,705 MW Martin County Power Plant, which is currently the single largest fossil fuel-burning power plant in the United States. This is the first hybrid solar facility in the world to connect to an existing combined-cycle power plant. As of 2012, no additional concentrated solar plants are planned for Florida.

This project was connected with large costs, approximately $476 million, and it has been calculated that it adds about 16 cents a month to the average FPL residential customer's bill. Martin Next Generation Solar Energy Center should have a respectable lifespan of 30+ years.

This large solar power plant has enough mirrors to cover 80 football fields and these mirrors are mounted to focus sunlight onto surfaces that add up to slightly less than the area of a single football field. The mirrors have been installed in aluminum frames to create long, linear dishes. The more than 6,800 frames each containing 28 mirrors have been arranged in parallel rows that are linked together for a total length of about 50 miles.

Solar panels and snow - minimum power losses

Snow and solar cells are not always put together in the same equation but this however does not mean that photovoltaic panels are not worth the investment in the areas characterized by long winters and plenty of snow. They can still be worth of money.

The major negative side in the relation solar panel-snow is that the layer of snow can cause a solar-cell blackout for awhile therefore significantly affecting its total output, and reducing its efficiency.

However, there are not that many people who live in areas characterized by heavy snow for more than a few months, meaning that in most cases photovoltaic panels do not stay under the snow for a very long time, and therefore do not require frequent snow cleaning.

Joshua Pearce, a scientist at the Michigan Technological University, even claims that in some cases snow is even able to improve the efficiency of solar panels. This is the so called „albedo effect“, and it refers to situation when sunlight reflects back from snow. This reflected sunlight can make a panel generate even more electricity than in normal conditions. The albedo effect is the same reason why for instance skiers get sunburn on sunny winter days.

The team of U.S. scientists recently created a computer model that is able to predict how much power generation would be reduced in relation to various amounts of snow cover and on different types of solar modules mounted at different angles. Afterwards, they validated their computer model with data from many of Ontario's large commercial solar farms.

The conclusion of this research will no doubt surprise many people as power losses were in most cases minimal, even in Canada, country characterized by large amounts of snow throughout the year.

The researchers were also able to create a model that can be used to design the most efficient photovoltaic systems, regardless of the amount of snow is in the area. This model should be of great help to solar energy developers all over the world, and should in best case scenario spread the use of solar panels to remote, isolated areas with plenty of snowfall.

The idea that solar panels are ineffective during the winter months was proved to be inaccurate one. Even their electronics functions better in the cold than on very hot days so solar energy can be effectively harnessed even during the cold winter months, as long as there is sufficient amount of sunlight present in the area.

This study is yet another proof that solar energy industry is slowly but surely passing all the obstacles on the road to success. The prices of solar panels are constantly decreasing, solar power technologies are becoming more efficient, and solar panels are spreading all over the globe. The future is certainly looking good for solar energy industry as things have been lately definitely going in the right direction.

EU leads the way in installing photovoltaics

The newly installed photovoltaics are appearing all over the world with Europe still leading the way. In fact, according to a latest study by the by the European Commission's Joint Research Centre, Europe accounted for two thirds of the global newly installed photovoltaic (PV) capacity in 2011, with 18.5 GW. With it, the Europe's overall PV capacity increased to 52 GW and solar power now accounts for approximately 2% of the EU’s electricity needs.

In the last decade or so Europe has been committed to clean energy policy with the special emphasis on solar energy. Translated in numbers this means that over the last ten years, the PV industry grew in Europe by an average of over 40% per year. This growth couldn't be achieved without the major drop in the production costs as PV production prices have decreased by approximately 60%.

The strong European solar power sector means that Europe is one step closer in achieving its goal of satisfying 20% of its energy needs from renewable energy sources by 2020.

Germany is still EU's photovoltaic leader (and global leader too). Behind Germany there were several other EU countries that have significantly improved their PV capacity. The EU solar leader list also includes Italy, Spain, the Czech Republic, France, Belgium, and the United Kingdom.

The photovoltaic industry is developing rapidly on global scale too. The global PV installation data shows that since 2000, global PV production increased by between 40 and 90%. The fastest growth in annual PV capacity over the last five years occurred in Asia, where China alone accounts for more than 50% of the new PV production.

Starting from 2010, and for the second year in a row, solar power was the most invested renewable energy source, with a total amount of 98.5 billion euros world-wide being invested. Two thirds of this total investment was concentrated in Europe.

China continues to challenge EU's lead in solar power development. China's massive investment in PV manufacturing has resulted in Chinese being by far the world's largest solar panel manufacturers. Though the China is world's largest solar panel manufacturer, Europe still leads the way in PV research and development, making constant innovations within the European PV manufacturing equipment industry.

The development of PV technology and its deployment has become a major business with solar energy industry being one of the fastest growing industries in the world. The global business knows no boundaries and we could soon see major partnerships between Europe, Asia and the United States.

The need for further PV innovation is still present in both efficiency as well as the costs. Solar power technologies are still connected with relatively high costs, and the efficiency of solar panels has plenty of room for further improvements.

Facts on buying used solar panels

Solar panels have dropped in prices by more than 40% in the last two years but regardless of this they are still quite an expensive renewable energy option for many homeowners and small businesses. This is the reason why plenty of people consider option that include buying used solar panels. Older solar panels can sometimes prove to be a real bargain and save you plenty of money, so this is definitely an option worthy to consider, particularly if you're on a very tight budget.

Nonetheless, you should be very careful when buying used solar panels because without the basic knowledge you could also end up buying some worthless or broken solar panel, and this is something you definitely want to avoid. Let's start from the beginning.

The first thing you should do is make the visual inspection in order to avoid buying solar panels with obvious damage. Solar panels with obvious damage (cracked, scratched, etc.) are usually the least expensive option but you should only buy these panels if you possess appropriate knowledge and technical skill to successfully fix these flaws.

The second thing you should pay attention to is the age of solar panel. As solar panels grow in age their efficiency tends to drop. The very important fact to mention here is that solar panels lose their efficiency only if they are actually used, meaning that stored solar panels do not lose their efficiency over the years. However, determining the actual age of given solar panel is not easy to do since some photovoltaic cells outlive their stated lifetime mark.

Solar panel also needs to have sound structure, meaning that if panel wasn't sealed properly there was a great chance for exposure to moisture, and moisture can have major negative impact on solar panel's efficiency.

Also make sure to test solar panel with voltmeter to measure its voltage. A 12 volt panel should show about 21 volts in maximum sunlight while panels designed to be connected in sets of 4 should show 4 to 5 volts. When it comes to voltage you should also be aware that if voltage fluctuates a lot or the voltage isn't 21 volts in maximum sunlight then there is great possibility that there is some damage with solar panel's internal circuitry (in most cases caused by corrosion). Fixing the damage with internal circuitry requires advanced engineering skills so unless you have them definitely avoid buying these panels.

You should also avoid buying used marine solar panels because they were likely exposed to lot harsher conditions than their land counterparts; salt water, for instance, makes corrosion more rapid so these solar panels are usually in the advanced state of corrosion.

Also older solar panels usually require more space per wattage than modern solar panels meaning that you need to provide them more space to use them in full capacity, and this can be an issue for some homeowners with shortage of available space.