New Solar Panels and New Scientific Breakthroughs in Solar Technology it seems are reported every month.But Solar Energy is still not competitive with Fossil Fuel Energy despite its obvious advantages.The costs of Solar Energy are declining quickly but they remain still some way from being on par with the dirty forms of energy like Coal.The reason for all these new exciting technologies which are reported in newspaper not being able to bring a fundamental change in the energy scenario is that the costs are too high.Bringing a new solar panel technology from the lab to the factory takes a lot of time and effort.During this time the incumbent technology like crystalline solar technology keeps advancing due to the massive global R&D dollars that are spend and the rising scale.This had made many new startups in solar technology like Solyndra ,Spectrawatt and others bite the dust.You can read about the large number of solar failures in the first wave of thin film solar bankruptcies .
Solar Technology That Works at Night
The newest fad or technology using solar energy is one which works at night.Note all solar technologies in operation today whether they are Solar Photovoltaic or Solar Thermal work only during sunlight hours.Some claim to work 24 hours but they use Energy Storage Technology. US Department of Energy’s Idaho National Laboratory in Idaho Falls has claimed a new Thin Film Solar Technology that can work at Night.Novack who is the team leader is claiming that his Solar Cells will have an efficiency of 46% compared to the 20% mainstream most efficient solar panels produced by Sunpower.
The technique produces a flexible substrate with nanoantenna instead of solar cells which can capture infrared spectrum of the sunlight which normal solar cells can’t do.These unique materials can absorb the heat of the earth as well because during night time the earth reflect the solar heat in the infrared spectrum.It remains to be seen how much these new solar panels will cost.Note innovative techniques have fallen by the wayside before (just ask Solyndra) before the harsh mistress of economics.
Note there are other technologies that proclaim new solar panels that are super efficient as well.I can bet that it will take a miracle before they can be commercialized given the rapid fall in costs of silicon solar panels.Read these new technologies here and here
Here are the main technologies in the solar panel business that currently are in commercial production and IMHO will continue to remain dominant in the near future.
Silicon Solar Panels
- Amorphous Silicon – Amorphous Silicon (a-Si) is the smaller cousin of the Polycrystalline Solar Panels ,the main difference being the amount of silicon being used on top of the glass substrates.Amorphous Silicon uses a fraction of the Silicon that is normally used in silicon solar panels.This means that the weight and cost of the solar panel is lower however the efficiency is also much lower.Earlier this technology has a lot of backers but after Applied Materials the biggest semiconductor equipment company abandoned this technology,most a-Si companies have gone under.However some companies like Sharp,Astroenergy are still backing this technology.Oerlikon the Swiss company has made improvement like introducing tandem junction to increase the efficiency.
- Microcrystalline Tandem solar panels- A new generation of microcrystalline tandem solar panels with far higher efficiency than the amorphous type has been developed in the past 2-3 years.The substrate for the tandem type is identical in size to the substrate for the amorphous type.The microcrystalline tandem solar cell consists of a microcrystalline solar cell placed on top of a conventional amorphous solar cell.Companies like Sharp,Mitsubishi are selling such types of solar panels in the 50-150 Watt range.
- Polycrystalline Silicon Solar Panels – Polycrystalline Solar Panels are the most used Solar Panels on the planet.These Solar Panels are made out of Polycrystalline silicon which can be as much as 99.9999% pure (also known as 4N pure,the 4 denotes the number of 9s after the decimal point).Polysilicon was primarily used by the semi industry till 5-6 years ago and the electronic industry used 9N pure polysilicon.These panels have an efficiency of between 13%-17% depending on the quality of the Solar Cells being used.When you go out to buy normal solar panels,this is the solar panel that you will typically get from your solar panel retailer.Note they are available in a wide variety of power ratings going from as low as 5 watts to 250 watts or more.Its possible to buy very cheap Polycrystalline Solar Panels due to the Solar Oversupply in the market.
- Monocrsytalline Silicon Solar Panels – Monocrystalline Silicon Solar Panels give the highest efficiency and have the highest costs of production as well.During Polysilicon Manufacturing,its possible to grow pure silicon made of a single crystal.The solar panels made out of this single crystal of pure silicon is called monocrystalline solar panel.Solar Cells Efficiency can vary from 18% to 24% for the normal monocrystalline silicon technology.Sunpower makes the highest efficiency crystalline solar cells on a commercial scale.Sanyo is the other company which makes the most efficient Monocrystalline cells .Suniva is challenging the two with a low cost process for making high efficiency monocrystalline solar cells.
Non Silicon Solar Panels
- Cadmium Tellerium (Cd-Te) Solar Panels - These solar panels are produced by the largest solar panel selling company First Solar.Other companies like GE and Abound Solar are also trying to produce solar panels using this technology.While concerns were raised aboutusage of Cadmium which is toxic,NREL has verified that the Cd-Te compound does not pose any danger to humans and environment.Note Cd-Te Solar Panels are cheaper than silicon solar panels as they have lower efficiency (which means they need more area to generate the same amount of electricity).These types of solar panels were earlier used mostly in ground mounted solar farms.However with increasing efficiency they are being sold for installation of residential and commercial rooftops (FS-3) as well.This technology has around 12% efficiency though GE has said that it has managed to attain 15% efficiency on commercial glass.Don’t know how much of it is true since First Solar only manages around 12% efficiency despite around 10 years of dedicated R&D.
- Copper Indium Gallium Diselenide (CIGs) Solar Panels - This Thin Film Technology has the highest Solar Cell Efficiency and a number of established companies like TSMC,Q-Cells,Honda and startups like Miasole,Nanosolar,Solyndra are using this technology.However its production is not easy as four different materials are used.Miasole has been claiming to have achieved an efficiency of 13.8%.General range is between 11-14%.Note Solar Shinglesbeing sold by Dow and Uni Solar also use this technology as its weight is much lower than normal silicon solar panels.CIGs Technology is also used in making flexible thin solar panels which can be used for camping,BIPV and other applications where weight is an issue.
Other types of solar panels which are in niche production are organic solar panels made by Dyesol,Copper Zinc Tin Sulfure Selenium (CZTS) Solar Panels being developed by Solar Frontier-IBM,Multijunction Solar Cell Panels developed by Emcore,Boeing and others.
New solar panels (Technology,That Work at Night) and How do they Differ from Old Solar Panels