To cut costs in solar cell production researchers will work to reduce the thickness of the cells.

A national team of UK scientists is embarking on one of the UK’s largest ever research projects into photovoltaic (PV) energy.
The £6.3 million PV-21 (Photovoltaic Materials for the 21st century), led by experts at Durham University, will focus on making thin-film light absorbing cells for solar panels from sustainable and affordable materials, Renewableenergyaccess.com reported.
Eight UK universities, led by Durham and including Bangor, Bath, Cranfield, Edinburgh, Imperial College London, Northumbria and Southampton, are involved in the project. They will work together with nine industrial partners towards a “medium to long-term goal“ of making solar energy more competitive and sustainable.
At present solar cells are made from key components such as the rare and expensive metal indium, which costs approximately £320 per kilogram. To cut costs in solar cell production the research team will work to reduce the thickness of the cells. Making a solar semiconductor thinner by one millionth of a meter in solar cells generating one gigawatt of power could save 50 tons of material.
Researchers will also experiment with sustainable low-cost materials that could be used in the manufacturing of solar cells and on the use of nanotechnology and dyes on ultra-thin silicon to capture increased amounts of energy from the sun rays.
Principal investigator Professor Ken Durose of the Department of Physics at Durham University said, “at present you would need tens of tons of very rare and expensive materials for large scale production of solar cells to produce sizeable amounts of power. Some of the materials currently used may not be sustainable in 20 years time which is why we have to conduct research into alternative materials that are cheaper to buy and more sustainable.“
The researchers hope that the project will ultimately lead PV to grid-parity. “Our medium to long-term goal is to make a major contribution to achieving competitive photovoltaic solar energy, which we hope will lead to an uptake in the use of solar power,“ said Durose.
The latest funding follows an initial four-year research project by PV-21 that focused on the development of thin-layer PV cells using compound semiconductors based on the cadmium telluride and chalcopyrite systems.
This new work will form the basis for testing new ideas over the next four years.
Chris Pywell, head of Strategic Economic Change at regional development agency One NorthEast, said: “This project will add substantially to the position of North East England which is already at the forefront of photovoltaic energy research. As well as the strengths of Durham and Northumbria universities that are demonstrated by this success, we have the PV development facilities at NaREC, the new PETEC facilities at NETPark, and great businesses such as ROMAG. The Agency, Durham University and our other partners are committed to building on this new project and our many other successes to ensure the region leads the UK in renewable energy.“
The four-year project is scheduled to begin in April 2008 and is being funded by the Engineering and Physical Sciences Research Council (EPSRC) under the SUPERGEN (Sustainable Power Generation and Supply) initiative. The goal of the SUPERGEN initiative is to help the UK meet its environmental emissions targets through a radical improvement in the sustainability of power generation and supply.

Biofuel production takes valuable agricultural land away from food, driving up the price of staple crops like corn.

Maybe it was simply too good to be true. For proponents, biofuels--petroleum substitutes made from plant matter like corn or sugar cane--seemed to promise everything.
Using biofuels rather than oil would reduce the greenhouse gases that accelerate global warming, because plants absorb carbon dioxide when they grow, balancing out the carbon released when burned in cars or trucks, Time.com reported.
Using homegrown biofuels would help the US reduce its utter dependence on foreign oil, and provide needed income for rural farmers around the world.
And unlike cars powered purely by electric batteries or hydrogen fuel cells--two alternate technologies that have yet to pan out--biofuels could be used right now.
But according to a pair of studies published in the journal Science recently, biofuels may not fulfill that promise--and in fact, may be worse for the climate than the fossil fuels they’re meant to supplement.
According to researchers at Princeton University and the Nature Conservancy, almost all the biofuels used today cause more greenhouse gas emissions than conventional fuels, if the full environmental cost of producing them is factored in.
As virgin land is converted for growing biofuels, carbon dioxide is released into the atmosphere; at the same time, biofuel crops themselves are much less effective at absorbing carbon than the natural forests or grasslands they may be replacing.
“When land is converted from natural ecosystems it releases carbon,“ says Joseph Fargione, a lead author of one of the papers and a scientist at the Nature Conservancy.
“Any climate change policy that doesn’t take this fact into account doesn’t work.“
Many environmentalists have been making the case against biofuels for some time, arguing that biofuel production takes valuable agricultural land away from food, driving up the price of staple crops like corn.
But the Science papers make a more sweeping argument. In their paper, Fargione’s team calculated the “carbon debt“ created by raising biofuel crops-- the amount of carbon released in the process of converting natural landscapes into cropland.
They found that corn ethanol produced in the US had a carbon debt of 93 years, meaning it would take nearly a century for ethanol, which does produce fewer greenhouse gases when burned than fossil fuels, to make up for the carbon released in that initial landscape conversion.
Palm tree biodiesel in Indonesia and Malaysia--one of the most controversial biofuels currently in use, because of its connection to tropical deforestation in those countries--has a carbon debt of 86 years.
Soybean biodiesel in the Amazonian rainforest has a debt of 320 years. “People don’t realize there is three times as much carbon in plants and soil then there is in the air,“ says Fargione.
“Cut down forests, burn them, churn the soil, and you release al the carbon that’s been stored.“
Worse, as demand for biofuels go up-- the European Union alone targets 5.75% of all its transport fuel to come from biofuel by the end of the year--the price of crops rises.
That in turn encourages farmers to clear virgin land and plant more crops, releasing even more carbon in a vicious cycle.
For instance, as the US uses more biodiesel, much of which is made from soybeans or palm oil, farmers in Brazil or Indonesia will clear more land to raise soybeans to replace those used for fuel.
“When we ask the world’s farmers to feed 6 billion people and ask them to produce fuel, that requires them to use additional land,“ says Fargione.
“That land has to come from somewhere.“
Industry groups like the Renewable Fuels Association criticized the studies for being too simplistic, and failing to put biofuels in context.
And it’s true that the switch to biofuels can have benefits that go beyond climate change.
Biofuels tend to produce less local pollution than fossil fuels, one reason why Brazil--which gets 30% of its automobile fuel from sugar-cane ethanol--has managed to reduce once stifling air pollution.
In the US, switching to domestically produced biofuels helps cut dependence on foreign oil, and boosts income for farmers.
But in all of these cases, the benefits now seem to pale next to the climate change deficits.
Fargione points out that if the US managed to use 15 billion gallons of ethanol by 2015--as is mandated in last year’s energy bill--it would still only offset 7 percent of projected energy demand. That won’t put Venezuela or Iran out of business.
This is all depressing news, especially if you’re a corn farmer. Biofuels are one of the few alternative fuels that are actually available right now, but the evidence suggests we be better off not relying on them.
In the end, the right kind of biofuel won’t be a silver bullet, but just one more tool in the growing arsenal against climate change.

If we wanted to create the ideal environmentally friendly energy source, it would be a fuel that is easy and economical to produce, and one that does not pollute our air when burned. That is exactly what researchers at Arizona State University (ASU) intend to develop in a new program that uses bacteria and sunlight to generate hydrogen, a clean fuel that produces no greenhouse gases, Physorg.com wrote.
The project is one of the first to be funded by the ASU President’s Intellectual Fusion fund.
This endowed fund is supported by two recent gifts totaling $22 million, and is used to make seed investments in research areas that push the boundaries of traditional academic disciplines.
Funding for the biohydrogen project ($2.5 million over five years) is being administered through the Global Institute of Sustainability, which, with ASU’s School of Sustainability has the goals of researching new, environmentally friendly technologies and educating students on sustainability.
ASU’s biohydrogen project aims to harness the energy in sunlight using microbial photosynthesis to produce hydrogen.
A second part of this project is to convert waste materials from the initial process to produce even more hydrogen.
“Hydrogen is the purest fuel you can think of,“ said microbiologist Willem “Wim“ Vermaas, a professor in ASU’s School of Life Sciences and the lead investigator on the project.
“It generates energy without releasing CO2 into the atmosphere. It is the ultimate clean energy technology because you are splitting water to make the hydrogen.
If you burn the hydrogen, you get water back. In essence, with our process you are converting solar energy into a clean fuel.“
“Of course,“ he adds, “there are many challenges to making this process work efficiently.“
Splitting water into its chemical constituents of hydrogen and oxygen can be done through other methods, like electrolysis.
ASU’s process is more elegant and does not require any energy other than sunlight. What makes the process work is finely tuned cyanobacteria to carry out the reaction.
Vermaas, a member of ASU’s Center for Bioenergy and Photosynthesis, said that in the laboratory researchers have used a cyanobacterial system to generate a small amount of hydrogen using only solar energy.
To optimize the system, the microorganism must be retooled to put most of the energy it gathers from sunlight into compounds useful for biohydrogen production.
The ASU researchers, who have years of experience working in this field, are using a cyanobacterium with a known genome and have developed it into a model organism for genetic and metabolic engineering studies.
Using its natural photosynthesis machinery, “we are now starting to direct more of the photosynthetic activity into biofuel production, yielding organisms that convert substantially more of the harvested energy into biofuels,“ Vermaas said.
One of the main challenges for the researchers is finding an enzyme for hydrogen production, called hydrogenase, which can operate in the presence of oxygen.
Hydrogenase enzymes are a key component to hydrogen production through the photosynthesis process. However, they currently are very sensitive to oxygen, a natural by-product of the splitting of water (H2O).
“If you make photosynthetic hydrogen, you also make oxygen and you have a problem because oxygen inactivates the very enzyme that you want to have working,“ Vermaas explained.
One part of the project, headed up by Ferran Garcia-Pichel in the School of Life Sciences, is to find heartier forms of hydrogenase.
Garcia-Pichel will be looking at systems that occur in nature.
“Preliminary data suggest that in a variety of natural habitats cyanobacteria can produce hydrogen, which means that unless there is some way the cells exclude oxygen from the process, their hydrogenase enzyme must be oxygen tolerant,“ Vermaas said.
“Boosting the oxygen tolerance of the hydrogenase is really a key to the overall system,“ he added. With a robust hydrogenase enzyme, the next step is to incorporate their genes into the model cyanobacterial system.
But the way they are incorporated and how the oxygen-tolerant hydrogenase is aligned with other enzymes in the cyanobacteria are critical to getting the system to work efficiently.
“We need to be able to effectively connect the hydrogenase to the photosynthetic reaction center complexes of the cyanobacteria,“ Vermaas says. “We can do that through metabolic engineering.“
Bacteria’s evolutionary drive is to multiply and in that process electrons and protons are used for the generation of energy and as building blocks for growth of the organism.
In the modified cyanobacterial system, Vermaas wants to divert electrons from their normal pathways and push them into new pathways that result in hydrogen production.
The third part of the project is to create a microbial fuel cell technology that uses the left over cyanobacterial biomass generated in the hydrogen production process as the energy source for additional hydrogen production.
The researchers will develop the scientific and technological basis for microbial fuel cells that oxidize organic materials in biomass at their anodes, while generating hydrogen gas at their cathode.