At the end of 2010, GM and Nissan introduced their long-awaited electric cars, the plug-in hybrid Chevrolet Volt and the all-electric Nissan Leaf. If these are successful, they could bring sweeping changes to the automobile industry, which has relied almost exclusively on petroleum to power its cars. But whether electric vehicles become popular depends on improving the technology, especially by developing better batteries.
The Volt and the Leaf use advanced lithium-ion batteries that the automakers calculate will last many times longer than the batteries in your laptop. But they’re expensive, and the distance they can power a car is limited. In the near term, better electrodes that store more energy using less material could help, such as the silicon ones Panasonic is rolling out (Tesla to Use High-Energy Batteries from Panasonic). And a new test could allow researchers to quickly sort through combinations of electrodes and electrolytes to find ones that will last for the life of a car (A Quicker Test for EV Batteries).
Over the long term, novel battery chemistries such as lithium-sulfur offer potentially much greater energy storage at a lower cost than lithium-ion batteries (Packing More into Lithium Batteries). And a new approach that uses fluid electrodes rather than solid ones could help break through the energy storage limits that make it hard for electric cars to compete with gas-powered ones (New Battery for Cheap Electric Vehicles).
Cheaper Solar Power
In many parts of the country, electric cars will essentially be coal-powered, running on electricity generated by the fossil fuel. Electric power is highly efficient, so they will emit less carbon dioxide than conventional cars. But if electric cars are to achieve their true potential for reducing pollution, they will need to use more renewable energy or low-carbon sources of electricity such as nuclear power (Giant Holes in the Ground).
Solar power saw significant advances this year, as conventional-solar-panel makers cuts costs and improved efficiency and laboratories rolled out advanced prototypes. China was a big part of the story, as its manufacturers refined their designs (Solar’s Great Leap Forward).
In the United States, government loan guarantees helped increase investment in solar technology, including by thin-film-solar makers such as Abound Solar (Solar Cell Maker Gets a $400-Million Boost). It is not clear, however, what will happen to federally supported industries when the money from the 2009 stimulus bill runs out (Cash for Infrastructure). Funding from the new Advanced Research Projects Agency for Energy (ARPA-E) is being used to find cheaper ways to manufacture conventional silicon solar panels (Making More Solar Cells from Silicon).
Meanwhile, laboratories made prototypes of potentially ultra-efficient new kinds of solar panels. Nanostructures help solar panels absorb light, increasing their power output by 30 percent or more (TR10: Light-Trapping Photovoltaics and Solar Cells Use Nanoparticles to Capture More Sunlight). Researchers are finding ways around the inherent physical limitations of semiconductors, demonstrating in a prototype solar cell an effect that allows photons to generate multiple electrons. This approach could increase solar power output by 50 percent (Upping the Limit on Solar Cell Efficiency). A novel approach that uses both heat and light from the sun to make electricity could potentially double the output of solar panels (A New Way to Use the Sun’s Energy).