Water district pumps water from a lake 75 miles south to a local lake
405 feet higher. They propose to build a hydro generation plant on the
end of this pipeline before dumping it in the lake.
Am I missing something here?
"Andy Asberry" wrote: (clip) Am I missing something here?
^^^^^^^^^^^^^^^^^^^^
Probably. We have a dam in California (maybe more than one, where they have
a large fore-bay. At night they use surplus electricity to pump water up
into the fore-bay. When demand is high, in the afternoon and evening, they
release the stored water to increase their generation capacity.
Yes. I'ts called "pumped hydro". The impeller is in the pipe, but, as
another poster said, they use excess capacity to suck the water up,
then use the gravity of that water to run the system as a generator.
The gain in the system comes from not having to have a separate "demand"
power plant that uses fossil fuels in the peak times.
There's one in Scotland, I think, that can generate several gigawatts
for about 3 hours at a time. They use it right after national socker
games when EVERYONE (apparently) puts on an electric tea pot.
We have several similar systems here in the US, too.
Sure wish I had a 405 foot head of water out behind me! I'd pump the
water up using a woodgas powered engine. Like having a HUGE battery
that never goes dead.
Pete Stanaitis
----------------
Andy Asberry wrote:
They must have discovered some new principle, 32 feet is all I've ever
heard of anyone sucking water up - and that's under ideal conditions.
Engineman
Yes. =EF=BF=BDI'ts called "pumped hydro". =EF=BF=BDThe impeller is in the=
pipe, but, as
veral gigawatts
"engineman" wrote: They must have discovered some new principle, 32 feet is
all I've ever
heard of anyone sucking water up - and that's under ideal conditions.
^^^^^^^^^^^^^^^^^^^^
Spaco misspoke. It wouldn't make sense to put the pump/turbine at the upper
level, for the reason you state, and also because the water would be sucking
on the turbine on the way down.
I skipped the meeting, but the Memos showed that Andy Asberry
wrote on Mon, 12 Jan 2009 18:27:50 -0600 in
rec.crafts.metalworking :
Yes.
Unless you believe that they believe they can recoup all the costs
of pumping the water up 405 feet.
--
pyotr filipivich
We will drink no whiskey before its nine.
It's eight fifty eight. Close enough!
Standard practice in the Snowy Mountains Hydro scheme (NSW Australia) is to
use cheap off-peak power to pump low water up high for use later on (peak
period) for power generation.
The water is simply stored energy.
Yes - they *do* do it.
--
Jeff R.
What they are doing, is keeping power plants running at night when
demand is lower, to pump the water. During the day when they get peak
demands, they release water through turbines to generate electricty.
There are losses, but by using untapped capacity at night, they gain
capacity during high demand, for a lower overall cost than building
another power plant.
Jon
On Mon, 12 Jan 2009 18:27:50 -0600, the infamous Andy Asberry
scrawled the following:
Maybe trying to recoup some of their pumping losses?!?
--
Acceptance is such an important commodity, some
have called it "the first law of personal growth."
-- Peter McWilliams, Life 101
I skipped the meeting, but the Memos showed that "Jeff R."
wrote on Tue, 13 Jan 2009 16:06:30 +1100 in
rec.crafts.metalwork>> I skipped the meeting, but the Memos showed that Andy Asberry
Ah, "cost" - they charge extra for the electricity delivered by
the pumped water. But does the amount of electricity produced equal
or exceed the amount consumed in the pumping?
--
pyotr filipivich
We will drink no whiskey before its nine.
It's eight fifty eight. Close enough!
Pumped storage in well-engineered, utility-scale applications typically
recovers over 70% of the energy consumed. So, economically, it's at least as
good as other large-scale load-balancing approaches, which, in most cases in
the US, is otherwise done with gas turbines.
Those big steam-turbine generators absorb pretty big losses in startup and
shutdown, so the utility companies gain, also, by keeping them running at
high capacity all night long.
--
Ed Huntress
"pyotr filipivich" wrote: Ah, "cost" - they charge extra for the
electricity delivered by
^^^^^^^^^^^^^^^^^^^^^^^^^
The water keeps coming down the river whether you can use it or not. During
peak load periods there may not be enough water to meet their generation
needs. During the wee hours of the morning there is more water than they
can use. Pumping water uphill into a pond is like charging a storage
battery--you get to use it later.
I skipped the meeting, but the Memos showed that "Ed Huntress"
wrote on Tue, 13 Jan 2009 12:05:11 -0500 in
rec.crafts.metalworking :
So compared to "completely" wasting the power, they only "lose"
30%, and can charge more for the 70%. Sound like a friend who used
to go to the horse races and bet everything. Lost a lot, but on the
whole, would come home with about 2/3rds of what he went with - all
legal winnings.
Yeah, there is that too.
pyotr
--
pyotr filipivich
We will drink no whiskey before its nine.
It's eight fifty eight. Close enough!
They charge less than they would otherwise, because they'd either be
charging you for wasted base capacity, or they'd be charging you
amortization plus fuel on gas-fired turbines for peak capacity.
Utilities have been doing this around the world for close to 100 years. It's
a money saver. In the US, it also saves gas and makes better use of coal or
nuclear -- sometimes, hydro.
No, it's not much like that.
It's the best way to go for load-balancing, where it's physically and
geographically possible.
--
Ed Huntress
This is a water district; not a power company.
Maybe I didn't explain this well. There is NO storage. They are
pumping it in one end of a pipe and putting the generator on the other
end. Power used and power generated is at the same time. Stop the
pump/stops the generator.
Seems to me placing a restriction in the pipe only increases the power
required to pump the water.
Maybe they figure the pipe is a transmission line. Possibly it is
cheaper than hanging wires.
In article
,
Jim Wilk> > > >
Seems like ordinary, garden-variety, load balancing to me. Overbuild
for anticipated loads. During the times your load is minimal use some of
your capacity, while the generators are lightly loaded, to pump the
water to the source.
Next day, when the load is highest drop the water back through the
penstocks to ramp up the other generators.
Power is cheap in the wee hours, especially if you're your own customer,
and loads are light. Then you use the "banked" water to pick up the load
during the day when demand is high and you can charge more.
You have to keep a crew on duty all night anyway. Why not let them do
something useful and cost effective?
If pipeline's high point is higher than the second lake (for example,
the lake is in a deep bowl), the difference between the potential
energy of the water at the high point and at 405 feet is available at
the discharge.
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