There are an estimated 84,000 dams in the United States which impound 600,000 miles of river, or about 17% of the rivers in the country. Within the next 15 years, more than 90% of the world’s rivers will be fragmented by at least one dam.
The battery industry is currently dominated by lithium-ion batteries. We have them in our phones and computers. They power electric cars. And they are increasingly being used to store energy generated by solar panels and other renewable energy sources.
One of the most exciting possibilities for future solar energy technology is that of solar cells that can be sprayed or printed on to surfaces like the windows of skyscrapers, the roofs of sports utility vehicles, or the walls of houses. And the expectation is that such technology would be far cheaper than today’s silicon-based solar panels.
Scientists at the Oak Ridge National Laboratory in Tennessee were trying to find a series of chemical reactions that could turn carbon dioxide into a useful fuel. But the unexpected occurred: they found that the first step in their process actually got the job done all by itself. The reaction turns CO2 into ethanol, which is already used to power generators and vehicles.