Green Power may destabilize grid

Mike O'Dell mo at
Thu Apr 8 06:58:56 CDT 2010

yup - well-understood problem.

the phrase is "dispatch reliability"

at the moment, every megawatt of alternative has to be backed
by a megawatt of combustion precisely because of this issue

last year, the Texas Independent Operations Area (larger than
just Texas) had a live demonstration. They were using circa
75-100 megawatts of wind power from a big farm in west texas
when a dry line formed and blew through very quickly. the wind
died and suddenly the TIOA was 50 megawatts short.

The interties worked, in that they carried
the load until TISO could spin-up needed peakers, but the blow to
the head with a 2x4 was felt all the way into Canada. The waves
bounced and rattled for quite some time and they almost had to
open the interties, which would have been bad news in Texas.

that confirmed what everyone feared would happen, so the operative
view now is that alternative generation cannot be used to carry
base-load generation until dispatch reliability can be fixed.

the current best battery technology being deployed on a test basis
in the US is a battery from NKK which was developed for Tokyo Electric.
it's called "NaS" - Sodium-Sulphur - liquids at about 300C.
TEC has all nuclear base-load generation and needs the batteries
for frequency control and peaking. the basic module supplies
a megawatt for 7 hours back to the grid through *big* interter/chargers.

the problem, of course, is they are EXPENSIVE. as the article alluded,
the competition is natural-gas-fired gas-turbine peakers, which come
in at about $2/watt installed. batteries are very far from that
right now. that may change, but Lithium-Ion is not going to do it.
and frankly, the thought of being within a couple of miles of
a megawatt of A123 cells is not comforting.

energy storage is absolutely critical for exploiting renewables,
and as the article said, there are lots of people trying lots of things.
that's what makes horse races. (grin)


On 4/8/10 7:07 AM, wb5mmb wrote:
> _______________________________________________
> Tacos mailing list
> Tacos at

"Of course it's hard!
If it was easy, we'd be buying it from somebody else!"

More information about the Tacos mailing list