Think of this as Volume 17, Number 17 of A-Clue.com, the online newsletter I've written since 1997. Enjoy.
Imre Gyuk , energy storage program manager at the Department of Energy, says it's not just because solar and wind are intermittant. It's also because an increasingly computer-driven society requires cleaner power.
You know this in your own life. If you have a desktop PC, chances are you have a Uninterruptible Power Supply (UPS) sitting under your desk, or at least a “power conditioning” power strip next to you – maybe both. Spikes can damage critical components.
And that's why Bill Gates has put money into Aquion, a company developing batteries made of cotton, carbon and manganese oxide, with salt water as its electrolyte instead of acid. It's why he has also put money into Ambri and its liquid metal battery, as well as Light Sail Energy, which is working on air storage.
One of the big secrets of American economic success right now is Gyuk's work in bringing storage to bear on our electric grid. DoE now has 111 storage projects going on, against 30 in the rest of the world. Some of Gyuk's investments have been failures, like Beacon Power, which went bankrupt despite installing its flywheel technology near Albany, NY, or A123, which is now owned by a Chinese outfit but has 32 Megawatts of storage online in West Virginia. Or Zinc Air, a company the DoE isn't currently backing, which is working on zinc-iron redox flow technology.
Gyuk estimates that for every 1 Mwatt of grid energy, we need about 200 Kwatts of storage, storage that can be turned on-and-off like flicking a light switch, in order to even out power fluctuations. By contrast, what GE is offering, natural gas back-up for renewable energy sources, is highly inefficient. It can take a half-hour to bring even a natural gas turbine online, Gyuk said, and the grid needs a much faster response.
A simple regulatory change can make a huge difference in getting this storage online, increasing the prices storage systems can charge for their services. One such change is currently before Congress in the form of HR 1465, an Investment Tax Credit for batteries. Another was FERC 890, a Department of Energy pay-for-performance plan on grid storage that doubled profit for storage companies at a stroke.
Lithium ion batteries have been getting a lot of headlines lately. They're used in your iPhone, and in the Boeing 787 Dreamliner. They're not perfect, but they can be recharged again-and-again, which is a key to success in this field.
Energy can be stored-and-forewarded on a grid-level, on a community level, or on an individual level. Gyuk offered an example of how individual energy storage might work.
What if electric car makers would, instead of just selling batteries in their electric cars, simply lease them for five years. A lithium ion car battery loses just 20% of its re-charging power in that time, Gyuk said, meaning its range declines by that amount. If the battery is sold, the owner may keep using it another year, or two, or three, accepting the lower range to save a few bucks. But the battery that comes in after such overuse has uncertain characteristics. If you lease the battery and take it back after that time, it still has about 80% of its capacity, and can be comfortably used in a grid energy storage system – on a large scale, a community scale, or even on an individual scale. (It could be tested, re-packaged, and re-sold for storing solar energy, for instance, as its original value would have been fully depreciated.)
The battery opportunity is what makes stories like this one, from the University of Illinois, so important. By applying nanostructure science to the cathodes and anodes in batteries, the Illini have able to make lithium-ion “microbatteries” that can be combined to store far more energy, and which charge 1,000 times more quickly, than other designs. Without using different materials, in other words, we can dramatically increase the storage density of grid batteries, at low cost.
The most exciting new material out there may be graphene, which you can think of as a Buckyball that has been turned into a sheet. It exhibits the same hexagonal structure you find on old soccer balls, and can be produced with a simple DVD burner. Graphene has its weaknesses – it can lose its structural integrity at the edge of sheets, creating a “windshield crack” effect across the sheet that may cut its effectiveness in half – but the material's opportunities are so vast that these kinks are being ironed out quickly, on a global basis. One way to do that: manage it alongside other materials like silicon.
“As energy storage becomes more important companies will come out of the woodwork,” Gyuk concluded in an Atlanta talk I covered recently. The DoE maintains a great site about its energy storage experiments at energystorageexchange.org.
This is the sweet spot right now in renewable energy, the point where the bleeding edge of technology meets real business needs, and where profit opportunities are vast for the most cost-effective solution. Storage today is where basic solar was at the turn of the century, but it may develop twice as fast.