Cool Energy-Storage Projects Popping up; Expect a Lot More

By David Roberts

Grist Magazine

Oct 28, 2011 - Tracking the politics of clean energy can be a surreal and dispiriting experience. D.C. is so swamped in fossil-fuel money, fossil-fuel lobbyists, and fossil-fuel-owned pols that the conventional wisdom is absurdly pessimistic about clean energy: It's unreliable, it costs too much, it can never work, blah blah.

Meanwhile, out in the real world, costs are plunging and the intermittency problem (insofar as it's actually a problem and not a talking point of the fossil crew) is being solved.

There are two ways to solve it: one is connecting more renewables over a wide geographic area, which generally requires more transmission lines and grid upgrade (for intriguing news on that front, see here); the other is adding energy storage, so solar and wind plants can provide power even when the sun isn't shining and the wind isn't blowing. That's what today's post is about.

I give you the Laurel Mountain wind farm, in West Virginia, (in the picture above):

That's 61 1.6-MW wind turbines, for a total of 98 MW. And here is the massive bank of lithium-ion batteries that the wind farm will be connected to:

That's the world's largest lithium-ion battery farm -- 32 MW worth of storage, courtesy of A123 Systems. The AES power company just announced yesterday that the wind/storage power system is up and running in full commercial operation. All told, it will feed 260,000 MWh a year into the power market along the Eastern seaboard. (For details, check out the full story at Forbes.)

It won't be the world's largest for long, though. Some time late next year, Duke Energy will switch on a 36-MW battery storage system, the world's (new) largest, attached to the company's 153-MW Notrees Windpower Project in west Texas. The storage system will use the proprietary dry-cell battery technology of a very cool company called Xtreme Power. The systems contain both dry-cell batteries and sophisticated power control technology, so they not only store power, they enhance grid reliability. As the CEO explained it to me a few years back, the storage system basically presents itself to the grid like a highly dispatchable power plant.

The energy-storage industry is still in its infancy. Over 99 percent of the energy storage installed globally is made up of pumped hydro, whereby surplus power is used to pump water uphill and then the water flows down, turning turbines, when spare power is needed. That's a solid, reliable way of doing things, but its efficiency isn't that great and it faces some geographic limitations. Tons of new and alternative technologies are coming online as we speak, though: compressed air, flywheels, molten salt, and several different kinds of batteries, including the distributed batteries in electric vehicles.

Discussions on storage often end with, "for now it's too expensive." In most cases, that's true, but it's misleading to treat the affordability question as though it's a binary switch, as though someday storage will flip from being too expensive to affordable. Right now, some forms of storage are cost-effective in some applications given some markets and regulations and some accounting methods. (See above!)

What will happen is, that small pool of affordable storage applications will grow larger, not only because the technology will advance but because accounting methods will change (full lifecycle cost accounting over extended time periods makes storage look a lot better), regulations will change, markets will change, and the engineering culture inside power utilities will change.

All this will happen, I predict, much faster than even the most optimistic projections now have it. Even as a kind of resigned fatalism-bordering-on-nihilism has gripped the political conversation, out in the world, clever people are doing ambitious, exciting things. Don't let politics fool you: This is an amazing time to be involved in clean energy.

David Roberts is a staff writer for Grist. You can follow his Twitter feed at twitter.com/drgrist.