Monthly Archives: April 2012

Nanocrystal-Coated Fibers help save energy

Researchers from Purdue University in West Lafayette have developed an efficient nanotechnology to convert wasted heat energy to generate electricity.

Waste heat refers to heat produced by machines, vehicles, electrical equipement and industrial processes for which no useful application can be found and is therefore regarded as a waste-by product. 58 percent of the energy generated in the United States is wasted as heat, according to Yeu Wu, assistant professor of chemical engineering at Purdue University. He adds: “If we could get just 10 percent back that would allow us to reduce energy consumption and power plant emissions considerably.”

We, from Green Turbine, totally agree. So what has Purdue University developed? Researchers have coated glass fibers with a new “thermoelectric” material. The new material comprises of lead telluride that takes the form of nanocrystals. When thermoelectric materials are heated on one side electrons flow to the cooler side, generating an electrical current. The crystals are coated onto glass fibers to make it more flexible and cost-efficient. Such fibers could be wrapped around industrial pipes in factories and power plants, as well as on car engines and automotive exhaust systems, to recapture much of the wasted energy to make it more fuel efficient. The “energy harvesting” technology might dramatically reduce how much heat is lost.

Another potential application for this product is to use it in buildings for air conditioning. Through a reverse process, the nanofiber material could absorb heat representing a possible solid-state air-conditioning method., Wu said.

For more info, see: www.gizmag.com/thermoelectric-energy-harvesting-nanocrystal-coated-fibers/22239/

Source: Clean Technica (http://s.tt/19Vgy)

British company develops tubular solar panels

Naked Energy a UK energy solutions company, has developed a new solar panel which generates both electricity and hot water through a hybrid design.

One of the key challenges of solar photovoltaics (PV) is that their efficiency drops if the panels get too hot. For every 1º rise in temperature [from 25°C], you lose half a percentage point of efficiency thus the panels start to generate less power. In a warm climate temperatures can reach up to 70 to 80 degrees. On top of that: Photovoltaics operate at maximum efficiencies of 18%, which means that most of the potential sunlight is not captured and potential energy is therefore wasted.

Solar photovoltaic cells and solar thermal collectors both profit from the sun. The former turns the light into electricity, while the latter turns it into hot water for heating. Guildford based Naked Energy has now created a hybrid solar PV and thermal panel that it claims improves efficiency at high temperatures by approximately 45% and can generate both electricity and hot water. This type of device is commonly referred to as PVT (photovoltaic thermal).

So, how does it work? The solar thermal panels are placed into vacuum tubes. Each solar cell can change the tilt, so it follows the sun for as long as it can. Inside each vacuum-sealed tube is a power-producing photovoltaic wafer. Sunlight hitting the wafer generates extra heat, which then transfers to the tube’s solar thermal collector using the company’s patented thermosyphon technology. The heat that is transferred away from the photovoltaic cells can be used for space heating, hot water, de-salination and cooling. As a result electricity generation increases as compared to conventional photovoltaic cells since the heat is taken away and cooling down the photovoltaic cell, it is possible to generate more electricity than conventional photovoltaic cells.

Via: cleantechnica.com/2012/04/05/uk-company-likes-its-energy-naked/
and
news.discovery.com/tech/naked-energy-tubular-solar-120411.html
Credits: Naked Energy

Putting grasslands at airports to good use

According to a new report from the U.S. Department of Agriculture, land which surrounds airports could become a significant source of biomass for biofuels According to the agricultural secretary Tom Vilsack converting airport grasslands to biofuel, solar or wind production will not only provide more environmentally sound alternative energy sources, but may also increase revenue for airports and reduce the local abundance of potentially hazardous wildlife to aircraft.

The recent study, which findings were published in Environmental Management was conducted by researchers from USDA’s Animal and Plant Health Inspection Service. The article indicates that airports may want to consider converting to alternative fuels where it is both economically and environmentally beneficial.

Federal regulations require airports to have a certain amount of land surrounding runways for noise control. Some of the qualities of that land mesh quite well with the ideal qualities of land for alternative energy production, according to the researchers. The most suitable alternative energy location would offer large expanses of idle land with little presence of wildlife, being mostly unsuitable for conservation initiatives and would not compete with human food production. Airport are one of the few places in the U.S. where the reduction of wildlife abundance and habitat quality are actually encouraged and it is also an area where you are not allowed to grow food crops. Both the Nature Conservancy and the U.S. Department of Agriculture think these lands are now going to waste: the former promotes wind energy, while the latter support the biofuel cause.

Researchers at the National Wildlife Research Center (NWRC) note that many airport properties are already managed to reduce wildlife abundance and habitat quality as part of efforts to avoid wildlife collisions with aircrafts. Ongoing and future NWRC research will look into biofuel crops that have low wildlife-strike risks and are compatible with safe airport regulations. NWRC researchers and collaborators are currently studying wildlife use of solar arrays and adjacent airport grasslands in Arizona, Colorado, Ohio and others, as well as wildlife use of experimental plots containing switchgrass and mixed warm-season native grasses in Mississippi.

The Indianapolis International Airport already begun putting their grasslands to a good use. Last year it approved a plan to lease out part of its property to a company for a solar panel farm that will include 41 thousand solar panels on 60 acres. The airport made sure the light wouldn’t cause glares and the panels wouldn’t become a nesting area for birds. For more info on Indiana, see: indianapublicmedia.org/news/airports-serve-solar-farms-28840/

Via: westernfarmpress.com/management/airport-grasslands-offer-biofuel-farmland

www.ethanolproducer.com/articles/8675/usda-explores-potential-for-biofuel-crops-at-airports

Britain’s first green church is 900 years old

The St. Michael and All Angels Church in Withington England has undergone a thorough green renovation and now has a biomass boiler for heat, and a solar array on the roof. The 12th century building is now believed to be the first church in England to be powered entirely by renewable energies.

The 24 solar modules were supplied by Kyocera Corporation, a Japanese firm, and have a total output of 3.12kw. The panels are installed on the roof of the church.They company says that the modules were carefully installed to meet strict regulations concerning historical buildings by using a special ladder system that did not adversely affect the structure of the building or its visual appearance.

Many churches in England were traditionally built so that the people in in it were facing east This means they have plenty of south-facing roof space that is ideal for placing solar panels. Green energy provider Ecotricty says that more than 100 church buildings in the South west of England have already benefitted from the High Court decision to extend the Feed-in-Tariff window for solar panels. With 16,000 church buildings throughout the UK, parishes are being urged to reduce their carbon footprint by making greener purchasing choices, in line with the Church of England’s national campaign – ‘Shrinking the Footprint’ – with a target of cutting carbon emissions by 80% by 2050.

The Church hopes that this pioneering project will serve as a reference project for the sustainable renovation of other historical buildings across the country.
Via:www.treehugger.com/renewable-energy/900-year-old-church-goes-100-renewable.html