Solar activity has had minimal impact on climate over the past millennium, new research from the United Kingdom indicates. The findings counter the long-held view that periodic fluctuations in the sun’s energy output have led to lengthy periods of warm or cold weather in the past.
A group of recent Massachusetts Institute of Technology graduates has developed a roof tile that remains white in summer to reflect the sun’s energy then turns black in winter to absorb the sun’s rays and heat buildings.
The so-called “thermeleon” (rhymes with chameleon) technology uses a common commercial polymer trapped between layers of plastic, including a black layer at the back. When the temperature drops, the white layer disappears, exposing the black layer.
The MIT graduates say the tiles reflect about 80 percent of the sun’s heat when they are white, translating into a 20 percent savings in cooling costs. When the tiles turn dark, they absorb about 70 percent of solar energy.
Summer’s comin. Sun, sand, beach and shiga toxin.
Yep, it’s a gene that can make swimmers sick. And health departments don’t test for it in places like Michigan and Pennsylvania. They test for E. coli, an indicator bug that’s much better known, but isn’t always harmful. So the beach you visit may be “clean” for E. coli, but not shiga toxin. That can keep you up at night, literally (severe gastrointestinal illness).
A two-year study by Mercyhurst College says there’s a need for standardized tests for specific pathogens like shiga toxin to better protect the public.
Talk about a Clean Tech opportunity.