The Green Embrace of Lead-Acid
Peter Huber, Forbes Magazine, 07.23.01, 12:00 AM ET
Some greens are quietly delighted that California's electric
grid can no longer be trusted. Now, at last, people will take a
good look at off-grid alternatives--solar, wind or fuel cells.
How envious your neighbors must be, if you already have a solar
panel on your roof. How virtuous you are to harness the pristine
sun, while they still patronize the grubby burners of coal. Just
don't mention the 300 pounds of lead-sulfuric acid batteries in
the basement. Or the backup generator in your garage that burns
three times as much fuel as a central power station does to make
the same amount of electricity.
Lots of businesses and homeowners sensibly embrace this
"distributed generation" because it provides backup
power, however green (or otherwise) it may be. But far too many
misty-eyed greens love it only for what it isn't--the hated
utility. Get past the mist, and distributed generation doesn't
end up green at all--not with the technologies that practical
people buy today.
Diesels burn diesel oil, perhaps the only fossil fuel filthier
than coal. And they generally burn it a lot less efficiently.
Most of them also emit more soot, sulfur and nitrogen-oxide
pollutants, and emit them a lot closer to where we live. Even
allowing for the (quite modest) losses on long transmission
lines, the big centralized power plant beats the backup diesel as
resoundingly as mass transportation beats cars.
Businesses get generators powered by truck engines. For
homeowners a motorcycle engine will do. Honda repackages one for
you as a portable or wheelbarrow-size generator. Home generators
are rarely more than 15% efficient. The power plants run by those
hateful utilities have efficiencies of 40% and up.
The most attractive technology of all for infuriated Californians
is plain old lead--a bank of lead-acid batteries. Dedicated
greens are big customers, too, though they don't boast about it.
The most hassle-free substitute for grid power at 4 p.m. is grid
power delivered to a lead-acid cell 12 hours earlier. If your
grid leads only to a solar panel or a windmill, you need the
time-shifting all the more, because green-power blackouts happen
as often as the sun sets or the wind dies down.
Not quite 15 years ago Southern California Edison set up 8,256
lead-acid batteries in a massive 10-megawatt array, 50 miles
outside of Los Angeles. The idea was to shift the demand for
central-station power from peak hours to off-peak hours. But if
you're going to deploy 8,000 of these lead-acid batteries, it
makes more sense to scatter them all across the Los Angeles area.
Which is just what many Californians are now doing. They're
snapping up the residential-size boxes (sold by Xantrex and other
companies) that seamlessly flip the power from the public grid to
battery bank and back again, keeping the charge-discharge cycle
out of sight and out of mind.
The sealed batteries manufactured for backup purposes (rather
than for starting automobiles) are now maintenance-free and last
20 years. And if they run down before a blackout ends, the
Xantrex switching unit comes with a convenient input plug for
your Honda generator.
The greens' fondest hope is that it won't be a generator, it will
be a solar panel or a fuel cell. If it is a fuel cell, it will
provide hot water and space heating, too, for terrific efficiency
overall. But when the fixed assets like turbines and wires are
priced properly, the grid's off-peak power has a very low
marginal cost--about 2 cents per kilowatt hour, roughly the cost
of the fuel. At that price it is usually much cheaper and simpler
to time-shift the utility's electrons than to generate your own.
Time-shifting adds reliability, but subtracts efficiency. And it
requires a whole lot of lead--the stuff they used to put in our
gasoline, until environmental regulators banished it.
We would do the planet a favor by upgrading the grid and
generating electric power in central power plants at 4 p.m., when
we need it, rather than at 4 a.m., when we don't. A
Harley-Davidson is driveway jewelry. More often than not, the
residential solar panel is green lawn candy.
Peter Huber, a Manhattan Institute senior fellow, is the
author of Hard Green: Saving the Environment From the
Environmentalists and the Digital Power Report. His law firm
frequently represents regional Bell phone companies. Find past
columns at www.forbes.com/huber.
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