Stories tagged solar

Bohmer's invention, a $5 cardboard box solar oven won the FT Climate Change Challenge, for the most innovative and practical solution to climate change.

Nanotube catalyst: 10,000 X smaller than human hairs
Nanotube catalyst: 10,000 X smaller than human hairsCourtesy St Stev

Solving the carbon dioxide problem

Burning fuel releases carbon dioxide and water vapor. A breakthrough process can reverse this reaction. The carbon dioxide and water vapor can be joined into molecules of methane, ethane, or propane by using sunlight as an energy source. The secret to doing this efficiently requires a particular catalyst with a large surface area.

(A) team (at Pennsylvania State University) found it could enhance the catalytic abilities of titanium dioxide by forming it into nanotubes each around 135 nanometres wide and 40 microns long to increase surface area. Coating the nanotubes with catalytic copper and platinum particles also boosted their activity.

Learn more:
Sun-powered device converts CO2 into fuel New Scientist

Jan
13
2009

Solar slowdown: Solar panel revenues projected to drop 19% in 2009
Solar slowdown: Solar panel revenues projected to drop 19% in 2009Courtesy richardmasoner

Global finances hurt solar industry

Suntech Power Holdings Co. Ltd., the world's largest solar module maker, suspended its plan to expand capacity by 40 percent in 2009. Instead, it laid off 10 percent of its 8,000 strong workforce.

Global revenues for photovoltaic solar panels are expected to drop 19 percent in 2009, believed to be the sector's first-ever contraction, as prices fall due to oversupply, research firm iSuppli said last December" Reuters

Say it aint so

My hope is that a change in government incentives will prove to be a game changer.

Additional news, First Solar

First Solar was featured by Investopedia yesterday as a solar company to watch in 2009.

Which forms of energy production should the government be subsidizing more? Nuclear or renewable technologies like wind and solar?

Sep
07
2008

Solar cells that work at night

Solar cells become ineffective when the sun goes down. At night, the earth radiates heat back toward the sky. Scientists at the U.S. Department of Energy's Idaho National Laboratory are working on a device to turn infrared radiation into electricity.

Nanoantennas convert infrared rays into electricity

Billions of nanoantennas printed onto thin, inexpensive sheets will transform heat energy into electricity. The physics behind this conversion is the same as that of a radio antenna. The only difference between radiowaves and infrared light is wavelength. Antennas 1/25 the size of a human hair resonate when bombarded with heat radiation. If the resulting alternating current can be passed through a rectifier (one way valve) the current can charge up batteries. The infrared rays create alternating currents in the nanoantennas that oscillate trillions of times per second.

"Today's rectifiers can't handle such high frequencies. "We need to design nanorectifiers that go with our nanoantennas," says Kotter, noting that a nanoscale rectifier would need to be about 1,000 times smaller than current commercial devices and will require new manufacturing methods. Another possibility is to develop electrical circuitry that might slow down the current to usable frequencies." Eureka Alert

If these technical hurdles can be overcome, nanoantennas have the potential to be a cheaper, more efficient alternative to solar cells. Computer models of nanoantennas predict up to 92% efficiency (compared to solar cells around 20%).

Learn more in this video, "Harvesting the sun's energy with antennas"

Aug
01
2008

Splitting water to store electricity: A snapshot showing the new, efficient oxygen catalyst in action in Dan Nocera's laboratory at MIT.
Splitting water to store electricity: A snapshot showing the new, efficient oxygen catalyst in action in Dan Nocera's laboratory at MIT.Courtesy MIT/NSF

Saving up energy for use at night

Want to be energy independent? Solar and wind energy are great but what do you do when the sun goes down and the wind doesn't blow? Batteries with the needed capacity are very expensive.

Energy can be saved up by breaking water apart into hydrogen and oxygen

Using a surprisingly simple, inexpensive technique, chemists have found a way to pull pure oxygen from water using relatively small amounts of electricity, common chemicals and a room-temperature glass of water. At night that oxygen can be combined with hydrogen (also extracted from water) in a fuel cell to make electricity.
The new process, enabling water to more easily be split, is to use a catalyst consisting of cobalt metal, phosphate and an electrode, placed in water.

"When electricity -- whether from a photovoltaic cell, a wind turbine or any other source -- runs through the electrode, the cobalt and phosphate form a thin film on the electrode, and oxygen gas is produced."
"The new catalyst works at room temperature, in neutral pH water, and it's easy to set up. That's why I know this is going to work. It's so easy to implement," Danial Nocera (MIT news office)

Within ten years

Nocera hopes that within 10 years, homeowners will be able to power their homes in daylight through photovoltaic cells, while using excess solar energy to produce hydrogen and oxygen to power their own household fuel cell. Electric vehicles will also power up from this home system.

Learn more: MIT News

Apr
27
2008

What is the best way to store solar energy?

Solar Two: Heat from the sun is stored in a tower containing molten salt.
Solar Two: Heat from the sun is stored in a tower containing molten salt.Courtesy United States Department of Energy
What is a good way to store solar energy for when the sun doesn't shine? Batteries are expensive and wear out. Instead of storing electricity, solar thermal systems store heat. A coffee thermos and a laptop computer’s battery store about the same amount of energy. The thermos costs about $5 and the laptop battery $150.

Molten salt at 1000+ degrees

By reflecting sunlight at a tall "power tower", tens of thousands of gallons of molten salt can be heated to very high temperatures (1000 degrees F). The heated salt is used to boil water into steam, spin a turbine and make electric power. By regulating the release of heat, generators can continue to run on rainy days and during the night.

"This technology has been successfully demonstrated and is ready for commercialization. From 1994 to 1999, the Solar Two project demonstrated the ability of solar molten salt technology to provide long-term, cost effective thermal energy storage for electricity generation."

SolarReserve will build solar thermal electric plants

SolarReserve, a company backed in part by United Technologies, is using funding from a U.S. Department of Energy grant to develop utility-scale solar thermal electric generating plants between 100-600 megawatts of electricity. One megawatt is enough power to supply approximately 1,000 US households. Read more at SolarReserves FAQ webpage.

Sources:
New York Times
SolarReserve website (includes a video)

Apr
19
2008

Popcorn shaped dye particles double cheaper solar cell efficiency

Popcorn-ball design doubles efficiency of dye-sensitized solar cells: A close-up of a single ball, taken with a scanning electron microscope. The 300-nanometer sphere is large enough to scatter light. But its insides are made of tiny grains just 15 nanometers across.
Popcorn-ball design doubles efficiency of dye-sensitized solar cells: A close-up of a single ball, taken with a scanning electron microscope. The 300-nanometer sphere is large enough to scatter light. But its insides are made of tiny grains just 15 nanometers across.Courtesy University of Washington
Dye-sensitized solar cells, which are more flexible, easier to manufacture, and cheaper than existing solar technologies just got even better.

By using particles shaped like popcorn, University of Washington researchers were able to increase solar cell efficiencies from 2.4 up to 6.2 per cent. The porosity of the large balls (300nm) allowed light to penetrate into the layers and bounce around between balls increasing absorption. Each balls surface was made of smaller spheres (15nm) increasing the effective surface area. One gram of this material has a surface area of 1000 square feet.

The research used the pigment zinc oxide, which is of lower efficiency than the commercially used titanium oxide, but easier to work with during experiments. Titanium oxide layers are expected to show similar gains. While titanium oxide cells currently have a record efficiency of 11 percent, the researchers hope that by using the new method they can by far surpass this old record, possibly even surpassing silicon cell efficiencies. Such progress could make silicon cells, used for decades, obsolete, replaced by cheaper, more efficient, flexible cells.

Source; University of Washington News

Dec
18
2007

Silicon solar obsolete soon?
Silicon solar obsolete soon?Courtesy D. O. E.

NanoSolar, cheaper than coal

Renewable energy becoming cheaper than fossil fuels may happen soon. Today, Nanosolar CEO Martin Roscheisen says his startup took a step in that direction by shipping its first thin-film solar panel (via TechCrunch). In a blog post, Roscheisen claims his company has produced

“the world’s lowest-cost solar panel – which we believe will make us the first solar manufacturer capable of profitably selling solar panels at as little as $.99/Watt.”

Electricity from a new coal burning plant costs about $2.10/watt.

Nanosolar can change the world

Popular Science gave Nanosolar's Powersheets the top technical innovation of the year award. The NanoSolar website provides this list of news and events:

You can watch a video showing how NanoSolar photocells are manufactured (via KQED).

Dec
03
2007

Making the world a better place

A philanthropic arm of the Google Foundation called Goggle.org drawing upon its nearly $2 billion in Google stock will invest "hundreds of millions" in companies specializing in renewable energy, co-founder Larry Page said.

"If we achieve these goals, we are going to be in the (electricity) business in a very big way," Page said. "We should be able to make a lot of money from this."

One gigawatt of renewable energy

Google's plan, known as RE< C, is to develop a gigawatt of electricity from renewable energy sources that will be cheaper than electricity produced from burning coal. Google is betting its R&D dollars on advanced solar thermal power, wind power, and enhanced geothermal technologies. Google's headquarters already draws some of its power from one of the country's biggest solar power installations.

"Cheap renewable energy is not only critical for the environment but also vital for economic development in many places where there is limited affordable energy of any kind," added Sergey Brin, Google Co-founder and President of Technology.

Google.org grants and investments

Two companies Google.com is working with are eSolar Inc. and Makani Power Inc. By focusing sunlight with mirrors, eSolar Inc. hopes to generate utility-scale power cheaper than with coal. Makani Power Inc. is developing high-altitude wind energy extraction technologies (Get more information via pdf downloads by clicking the company names).

"Google.org's hope is that by funding research on promising technologies, investing in promising new companies, and doing a lot of R&D ourselves, we may help spark a green electricity revolution that will deliver breakthrough technologies priced lower than coal." (Nov 27 Google press release)

Sources & resources: Yahoo News and Google.com and FAQ