Green Options

Solar venture investments hit a three-year low in the second quarter, the Cleantech Group said Wednesday. According to Brian Fan, senior director of research for the group, solar startups in North America, Europe, China and India raised a total of only $113.8 million for the quarter, which is down 7 percent from $365.7 million in the first quarter and down 86 percent from $834.7 million in the year-ago quarter.

Move over, silicon: graphene is ready for its closeup.  Discovered just a few years ago, graphene is a sheet of graphite the thickness of just one atom.  It can be processed like silicon to make electronic devices, which makes it easier to manipulate than the current “it” material, carbon nanotubes.  Without the breakdown problems that beset silicon at the nanoscale, graphene is bringing the dream of a molecule-sized computer closer to reality.

Researchers at the Georgia Institute of Technology have developed a new treatment for silicon photovoltaic solar cells that creates bumps and peaks on the surface that increase cell efficiency in two ways.

According to a new study conducted by the Lawrence Berkeley National Laboratory, The average installed costs for photovoltaic cells (in real 2007 dollars) went down from $10.50-per-watt in 1998, to $7.60-per-watt in 2007.

What’s most amazing about this report is that it appears to validate a whole slew of state and local solar initiatives. The researchers found that—despite the many, many reported advances to solar cell efficiency—most of the savings during this nine year period came from reductions to installation and external hardware costs.

Researchers at Lawrence Berkeley National Laboratory released a study this week concluding that the solar industry could use many cheaper and more abundant alternatives to silicon, including iron pyrite — most commonly known as fool’s gold.

In total, the researchers found 23 alternative semiconductors, but only 12 are more easily found than silicon. Iron pyrite was named the most probable solution among those 12. Solar producers have often faced shortages of silicon, so even one new material would be a welcome jolt for the industry.

Sun Well Solar—a subsidiary of the notoriously poor CD and DVD manufacturer, CMC Magnetics—has announced today that it is one month ahead of schedule in the ramp-up of its new photovoltaic production line.

Since the late 1800s, the primary impediment to the adoption of electric vehicles has been battery technology. And while the technology has advanced by leaps and bounds in the last decade or two (compare your cell phone with one from the early 90s), with a threefold improvement in energy density and more than an order of magnitude improvement in power density, it still lags behind gasoline.

Some have argued that current technology is sufficient — that the ability to drive 1 1/2 hours to 3 hours nonstop is good enough for the overwhelming majority of trips, and that paired with a range extender, rapid chargers, or battery swapping, you have a viable means of replacing the gasoline car. However, there still is a great deal of pressure to get electric vehicle range up to that of gasoline.

Enter Yi Cui. Again.

Solar PV manufacturer Oerlikon Solar has pioneered a new thin film solar technology process, which it claims has made its solar cells 7 per cent efficient - a 16 per cent energy improvement over its previous technology. The advance has led to a 50 per cent increase in the capacity of its thin film solar fabrication plant.

So, why is this important? Well, thin film cells are typically a lot cheaper to produce than more common silicon solar cells, but often suffer from significantly lower conversion efficiencies. Oerlikon’s breakthrough moves us a lot closer to the day when thin film becomes more cost-effective than silicon-based panels - which could mean a dramatic rise in the adoption of solar power in homes and businesses.

Solar energy is necessary for our transition to a sustainable economy, but a recent study in Geophysical Research Letters suggests that the industry may be harming the environment. Nitrogen Triflouride (NF3), a greenhouse gas used by the semiconductor industry to clean the chambers where silicon chips are produced, has 17,000 times the globe-warming capacity of CO2. Now researchers believe that emissions of the gas are up to 4 times higher than previously thought—perhaps as high as 16 percent.

The solar cells, about the size of a 12-point font letter ‘o,’ are being tested to eventually power microscopic machines, such as those used to test chemical leaks in the air.

The researchers at the University of South Florida say these are some of the smallest solar cells ever, with twenty aligning to form one panel at just one inch. Typical single cells are around two inches across on their own, and then form the large silicon panels we see on rooftops.

Many new solar energy companies are working on silicon alternatives, but 1366 Technologies is taking a different approach— the MIT-founded company has invented both a new cell architecture for multi-crystalline solar cells and a manufacturing process to lower the cost of the cells. The process is so effective that 1366 believes it can make solar cost-competitive with coal by 2012. And with this week’s opening of the company’s solar manufacturing facility, that vision may actually come true.