Green Engineers Shine During National Engineers Week
In honor of National Engineers Week (Feb 15-21), it seems fitting to update readers with some of the latest trends and tips in Sustainable Energy practices.
Some of the fastest growth in renewable energy has been in thin film solar modules and the use of advanced materials other than silicon (see “The ‘Greener’ Solar Panel in Mercer” in the 11/20/08 Lawrence Ledger). As our neighbors at EPV Solar found, these thin film modules are cheaper to make, use less silicon material, and have other technical advantages over conventional solar cells. Scientists are also working on new materials, like copper indium gallium diselenide (CIGS) to dramatically increase solar absorption. Researchers at the Massachusetts Institute of Technology (MIT) are even using multiple layers of thin materials, each one “tuned” to a different color of light to maximize the amount of energy absorbed.
Maybe just as remarkable as the advances in solar is another technology from MIT that allows solar energy to be stored. Inspired by the process of photosynthesis in plants, Professor Daniel Nocera has developed a process to separate hydrogen and oxygen in water using the sun’s energy. The hydrogen and oxygen can later be used in a fuel cell when the sun is not shining. Although still in the research phase, this may have great potential for a homeowner market.
And speaking of residential products, the Department of Energy (DoE) has recently begun offering the Energy Star rating to energy conserving water heaters. Five types of water heaters (high efficiency gas storage, whole-home gas tankless, solar, heat pump, and gas condensing) should be available in 2009. According to the DoE, hot water is the second largest energy consumer in a household (after heating and cooling). A typical home can spend $400-$600 per year on hot water. These new Energy Star models can cut the energy use anywhere from $30 to $290 per year.
My article this time last year in the Lawrence Ledger (see “Have You Hugged an Engineer Today?” in the 2/22/08 Lawrence Ledger) introduced some of the technologies the DoE is looking at for long term capture and storage, or sequestration of Carbon Dioxide. Although some programs have slowed due to funding or technical challenges, the DoE is continuing many sequestration activities. Some of the newer alternatives being considered include finding ways to chemically or biologically convert CO2 instead of simply storing it. Two chemical compounds that are promising are magnesium carbonate and CO2 clathrate. These solid compounds are much more compact than gaseous storage. Scientists are also looking at mimicking biological systems that use CO2 (like photosynthesis) or convert it into other useful compounds (e.g. methane or acetate).
While Engineers and Scientists may not have all the answers today, rest assured they are hard at work on producing sustainable products for tomorrow.
