The Stirling engine also needs the temperature gradient to work, but its design means that this can be much lower, so it can run by setting it on a nice cup of tea. That's because it can exploit very ...

Have you ever imagined a bike powered not by gasoline or electricity, but by the simple act of heating and cooling air? It might sound like something out of a science fiction novel, but the concept is ...

Earlier this week, we wrote about setbacks at some Silicon Valley companies with new solar technology. They’re built on real science and work in the labs, but they’re grappling with the real-world ...