Speed alone may be the factor that draws many sports fans to the bobsled, luge and skeleton events at this year's Beijing Winter Olympics. But beneath the thrilling descents of the winding, ...

A gravity assist is a technique where a spacecraft uses a planet's gravity to change speed and direction without burning fuel, effectively stealing a tiny amount of the planet's kinetic energy. Kruger ...

Energy Vault’s EVx storage system is comparable to pumped hydro, using grid-scale renewable energy when supply is abundant to drive motors and raise 30-ton blocks on a six-arm crane tower, rather than ...

Why it matters: Gravity batteries are a potential candidate for storing excess renewable energy, but finding places to install them is a challenge. Researchers have proposed that abandoned mines ...