One of the great underappreciated issues of renewable energy isn't whether seagulls are banging into turbine blades. It's whether intermittent sources of power have any real value in a world without energy storage.
But that won't be as big an issue if a new battery technology finds its way to the market. The battery, developed by a startup called Liquid Metal Battery Corp. (LMBC), could serve as a form of storage for everything from electric utilities down to single-family homes and virtually everything in between. Moreover, it has significant investors behind it, including Bill Gates.
The grid storage battery uses a high-density electrode on the bottom (red), a molten salt electrolyte (yellow),
and a low-density liquid metal (green) at the top.
Source: Liquid Metal Battery Corp.
"People love renewables," the company's founder, Donald Sadoway, who is also the John F. Elliott Professor of Materials Chemistry at Massachusetts Institute of Technology, told us in an interview. "They love solar. They love wind. But both of those technologies are intermittent. And we don't need intermittent boosting of the grid. We need reliable power."
Sadoway's idea is to build "a honkin' big battery" -- a unit as large as 1,000 cubic feet that uses hundreds of cells, each the size of a pizza box. The battery's advantages are that it is cheap, can be made big, and offers high energy density. Ultimately, the company believes such a battery could fill the storage role if it drops its cost to $100/kWh, but Sadoway and the company's executives are not saying what their battery costs today.
"Our batteries will be big, and we'll get economies of scale from that size," newly appointed CEO Phil Giudice told Design News. "And if we can provide cost-effective storage, we could have thousands of these being used by a single big utility."
Apparently, important people agree with that vision. Gates, who had reportedly seen some of Sadoway's online lectures at MIT, is one of two major investors in the company. The other investor is the French firm Total Group, which describes itself as a multinational energy conglomerate with 96,000 employees.
Gates has been open about his reasons for supporting the startup. Without inexpensive storage, "renewable energy sources like wind turbines and solar cells will never approach the scale or affordability that is necessary," he wrote in a Web article titled "We Need a Battery Miracle."
The reason storage is so important is extraordinarily simple but often ignored. Wind turbines generate power only when the wind blows, and solar cells make power only when the sun is shining brightly. Like all other sources of power -- coal, hydro, nuclear -- the electrical current from wind and solar sources must be used instantly. With a few minor exceptions, such as pumped hydro and compressed air energy storage, utilities have few ways of storing electricity for later use.