Wednesday, 7 April 2010

Wind intermittency problem solved conclusively and cost effectively.

Out on the web, it's recently been reported that the town of Presidio, Texas (population approx 7,500) has just installed a large sodium sulfur battery with a capacity of 32 MWH which they have affectionately named "Bob" at a cost of $25 million dollars. That's interesting you say, so what?

Well this is the final step in making wind non intermittent.


This battery is capable of powering the entire town's entire electricity needs for 4 straight hours.

So what?

Well, do the math. At a total cost of $25 million dollars, that comes out to about $3K per resident.

$3K per resident is hardly going to break the bank.

If this technology was implemented in wind farms all over the country it would lead to a situation where excess wind power could be stored and delivered on demand.

That would in turn lead to a much higher percentage of wind as a proportion of generating capacity being installable without having to upgrade the grid.

In addition, this technology makes it possible for wind turbines to compete as storable sources of energy for electric vehicles. Imagine this: along the interstates, there are car charging stations built with their own windfarms attached along with a number of these sodium sulfur batteries. The energy to charge the cars is gotten from the wind when the wind is blowing but delivered ON DEMAND. We're talking effectively about fixed price fuel for driving in unlimited quantities.

A scientific american article has this to say
So Xcel Energy, Inc., has become one of the first utilities in the U.S. to install a giant battery system in an attempt to store some of that wind power for later. "Energy storage might help us get to the point where we can integrate wind better," says Frank Novachek, director of corporate planning for the Minneapolis-based utility with customers in Colorado, Kansas, Michigan, Minnesota, New Mexico, the Dakotas, Oklahoma, Texas and Wisconsin. "The overall cost of electricity might be lower by using energy storage."

The energy storage in question—a series of sodium–sulfur batteries from Japan's NGK Insulators, Ltd.—can store roughly seven megawatt-hours of power, meaning the 20 batteries are capable of delivering roughly one megawatt of electricity almost instantaneously, enough to power 500 average American homes for seven hours. "Over 100 megawatts of this technology [is] deployed throughout the world," Novachek says. The batteries "store wind at night and they contract with their utility to put out a straight line output from that wind farm every day."

That removes one of the big hurdles to even broader adoption of wind power: so-called intermittency. In other words, the wind doesn't always blow when you want it to, a problem Texas faced earlier this year when a drop in wind generation forced cuts in electricity delivery. But with battery backup, the 11-megawatt wind farm outside Luverne, Minn., can deliver a set amount of electricity at all times, making it more reliable or, in industry terms, base-load generation. Plus, the battery effectively doubles the wind farm's output at any given moment—both the megawatt being produced by the wind farm itself (that would otherwise have gone to charging the battery) and the megawatt delivered by the battery.

These guys are not the only ones either. Ceramatec, VRB Power Systems, IBM and others are all working on advanced batteries of one kind or another.

Since the cost of installation of wind turbines are currently on par with new gas turbines, and dwindling supplies of coal can only get more expensive as time goes on, it seems we are now closing in on the end of the fossil fuel age.


Barba Rija said...

3K per resident is still huge. Remember this is not the main power source, just a battery.

DB said...

Hi Barba,

It's huge but not HUGE.
$3000K is something that the average US resident could pay off in a year.

If it was amortized over 10 or 20 years it's buttons.

And as for it not being the main power source: we don't need it to be. This is not about storing enough power because the wind might go out for three straight days and we have no alternate sources, it's just about having enough storage to make wind able to do load following. This capacity battery is more than adequate for load following.

DB said...

There's more:
If you hunt around on the internet, there are decent applications of wind that don't need 100% on-demand. Examples are large scale refrigeration plants which could be cooled a little bit cooler while the wind is blowing hard and allowed to warm up a little while the wind is not blowing.

Other examples are water desalination plants such as the one in Perth, Western Australia, which is entirely supplied by a wind farm which produces three times more power than the de-sal plant needs. This plant provides water for 400,000 people.

I think we are very, very close to being able to kiss fossil fuels goodbye in selected areas right now and in all areas within a decade technically (though most likely not for a generation practically).

DB said...


I wrote in my reply to Barba $3000K where I should have written $3K.

Mea Culpa.