From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Solar Power can now be stored?
Date: Tue, 05 Aug 2008 23:51:35 -0400
Message-ID: <356i949vluiv7ca986dgl6st0okbt0p05g@4ax.com>

On Tue, 05 Aug 2008 22:29:54 -0400, LouB <LouB@invalid.com> wrote:

>This might be of interest: http://www.pickensplan.com/

It's tragic to see a great businessman like Pickens make a fool out of himself
in his declining years.  But that's what happens when one fools around in an
area where he knows nothing.  That'd be like me trying to practice
neurosurgery.  You'd think that people would have learned from the other Texas
mental midget - Perot.

>Also, this story from July 18th should be of interest.
>http://www.statesman.com/news/content/news/stories/local/07/18/0718wind.html

What a hideous article!  Only thing worse than the writing is how much money
Texans are going to have to pay for this boondoggle.  A few things the article
doesn't mention.

1) When the wind zealots quote megawatt figures, they quote theoretical
capacity and not actual capacity.  Theoretical capacity is the energy that
could be generated if the wind blew continuously at the design basis speed.
The actual capacity is what the thing actually generates.  According to the
utility trade journals that I get, nationwide, wind capacity factor is below
40%.  That is, they're only making about 40% of their theoretical capacity.
Take each one of those claims and multiply by 0.40.  More on Texas in a
minute.

2) Even if the things achieved 100% capacity factor, all the units installed
in Texas are equal to a little more than one nuclear unit or a little less
than 3, depending on how the horribly worded sentence is interpreted.  A
typical nuclear plant makes 1,200 megawatts.  24/7.  Industry wide, the
nuclear capacity factor is about 94% and improving.  The 6% downtime is mostly
for refueling outages.  High burnup fuel and a few other changes are extending
the interval between refuelings from 18 months in the past to nearly double
that now.

3) Wind and solar are so erratic (no 'trons when the wind doesn't blow or the
sun doesn't shine) that they have a destabilizing effect on the grid.  A
recent article in "Power Engineering" magazine delved into the technical
issues involved in absorbing even 30% of the grid's capacity in solar and
wind.  The problem is, there have to be "rotating reserves" equal to the solar
or wind generation capacity online and ready to pick up load instantly when
the clouds come in or the wind stops.  This is the most expensive generation
on the grid - usually simple cycle gas turbines.  The more efficient combined
cycle gas turbines can't respond fast enough and the secondary steam plant
can't stand the frequent temperature cycling.

The sodium-sulfur batteries that I mentioned in another article will go a ways
toward addressing this problem because they can be online all the time while
costing practically nothing to keep in ready standby - basically just the
power to operate the controls and keep the cells heated.  They're still quite
expensive on a dollars per megawatt-hour of energy stored basis.

4) The wind does stop blowing.  That happened in Texas a few months ago.  I
can't recall the details but it was headline news in another of the trade
monthlies that I get.  The wind just... quit... blowing.... The entire wind
farm went dark in just a few minutes.  The state's grid operators performed
"heroics" (the magazine's words, not mine) that narrowly avoided a NY-style
wide-area blackout.


What is disgusting is that the $5 billion that they're blowing on this
transmission line to nowhere could build one and probably two nuclear plants,
sited near the major load centers.  Each plant would produce from 1200 to 2400
megawatts, depending on the size units selected.

This is profligate money wastage on a level as bad as the very worst of the
old nuclear industry.  This makes WHOOPS, er WPS look conservative in
comparison.

On the upside, someone recently sent me a url to a document on the NRC's
website listing the nuclear plant license applications currently in progress.
There are about 60 units on the list.  Some in the conceptual stage but others
about ready to start moving dirt.

John

From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Solar Power can now be stored?
Date: Wed, 06 Aug 2008 14:51:15 -0400
Message-ID: <49rj949vn8l1gtoactqhpt9hi5srf5nn2h@4ax.com>

On Wed, 06 Aug 2008 09:23:20 -0500, Bob Giddings <bobg@escapees.com> wrote:

>On Tue, 05 Aug 2008 23:51:35 -0400, Neon John <no@never.com>
>wrote:
>
>
>>3) Wind and solar are so erratic (no 'trons when the wind doesn't blow or the
>>sun doesn't shine)
>
>And yet, when you are, say, being battered by the continual
>roaring wind up and down the Columbia River in Oregon, or out in
>the flats of North Texas, with both hands in a death grip on your
>steering wheel and blown sand eating the paint off your car, you
>can't help thinking:
>
>"Man, this is a lot of power going to waste!"

I look at a lightning bolt the same way but damned if I can figure out how to
harness it.

>It has it's niche, surely.

As long as it stays a small niche.  But they're spending serious money there
in Texas and basing a large part of their capacity expansion plans on wind.

As I mentioned before, the problem is, we don't yet have an economical method
of backing up these systems when they occasionally just quit.  Around here we
have Raccoon Mountain pumped storage but even it can't react that fast.
Neither can the, IMO, somewhat misguided efforts to store energy as compressed
air in spent gas wells and salt mines.

Look at most any individual house that uses solar and/or wind as its primary
power source.  Off-gridders, they're called.  They ALL have LARGE (sometimes
thousands of amp-hours at 24 or 48 volts) battery banks that store the highly
erratic solar and wind energy. Most also have backup generators. Problem is,
there isn't yet a practical battery that can back up a 1 megawatt wind
turbine.

Until and unless technologies like those sodium/sulfur batteries become
economical enough to deploy in large quantities, either solar and wind remain
tiny niche producers or you accept fairly frequent power outages.

I'm living in that frequent power outage environment right now.  Extended
power outages are a weekly affair.  The one yesterday lasted 4 hours.  It came
within seconds of catching me in the shower all soaped up. (no power, no well
pump).

I've split my cabin's electrical system into two circuits, Vital bus and
balance-of-plant (nuclear plant terms).  The vital bus is powered by a large
UPS and battery bank.  On it are lights, my computers, optionally,
refrigeration (at the flip of a transfer switch) and a few other things.  I'm
about to parallel in another inverter to power the well pump.  They've caught
me a couple of times now in the shower and that's unacceptable.

It's kind fun for this nerd to mess around with his power system and the
mountain resort environment more than makes up for the inconvenience but do
YOU want to live like that?  I wouldn't if I were stuck somewhere other than
right here where I can hop on my e-scooter and in 5 minutes be on one of the
best trout streams in the country.

It almost never gets above 85 degrees here.  Whole 'nuther situation when it's
100 outside and the power goes off.

John

From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Solar Power can now be stored?
Date: Thu, 07 Aug 2008 15:59:32 -0400
Message-ID: <fejm945qesep8eoscnnh5g4maotesp3q8f@4ax.com>

On Wed, 06 Aug 2008 22:11:20 -0400, John Andrews <andrewsjp@chartertn.net>
wrote:

>
>I haven't heard anyone talk about pumped storage for saving wind
>power.  If a large water source is available and room for a big
>pond, then pumped storage is a realistic method of storing
>energy for electrical energy.  Two big iffs, of course and the
>enviros will probably have a fit, but it is the only way that I
>can see to have wind be a useful addition to the grid.
>
>John Andrews, Knoxville, Tennessee

I had some involvement with Raccoon Mountain. I ran a dozer during the tunnel
boring and ran the locomotive that hauled the turbine wheels from Southern's
line to Sequoyah's barge dock where they were loaded onto a barge headed for
the project.  I managed to derail one in the process :-)  I went back after
the project was completed for some hands-on operations training.

The last part is what forms this opinion.  Raccoon Mountain (RM) is GREAT for
keeping Sequoyah and Watts Bar base-loaded and equally great at peak shaving
during the two known and predictable peak times during the day.  It would be
lousy for following solar or wind, though.

The reason is that it can't respond fast enough.  It takes the better part of
an hour to bring up a turbine from cold standby.  Even with all systems ready
to run, it takes probably 10 minutes to spin up a turbine and sync it to the
grid and a few more minutes for it to pick up load.

Both solar and wind can and do go away much faster than that.  For solar,
think about a thunderstorm rolling in at 50 mph. As a dispatcher, do you waste
valuable stored energy spinning up the RM turbines when it isn't evident
whether the storm is going to hit the solar farm?  If he spins up and the
storm misses, that's wasted power that has to be paid for from other revenues
- yours and my power bills.  If he gambles wrong and doesn't spin up, a
blackout may follow the storm.  I don't envy those guys their jobs now, much
less if they have to deal with significant so-called renewables.

It is routine for wind farms to lose many megawatts of output in just a few
minutes.  Even in cases like the Texas affair that I commented on earlier, the
loss of the whole farm's output took less than 15 minutes.

Whatever picks up that load has to respond practically instantly.  A gas
turbine spinning and synced but idling with little to no load.  A future NaS
battery bank that can switch on in less than a cycle.  A hydro generator
spinning and synced but at no or light load.

Raccoon Mountain or any other pumped storage as presently constituted couldn't
do that because spinning the turbines at light load would waste most of the
energy it took to fill the reservoir - the turbines aren't very efficient at
light load.  That's why there are so many small ones at RM.  Bring 'em on in
increments as needed but run 'em fully loaded.

RM's motor/generators could be kept spinning, synced to the line, with the
generator motoring the turbine wheels.  That would be quite wasteful of
electricity.  It might be worth it though.  Perhaps the motor/generators could
idle with their fields over-excited, feeding leading VARs to the grid to help
correct power factor.  Perhaps the turbine scroll could be made air-tight and
a vacuum drawn on it while idling to reduce windage losses on the turbine.
Lots of engineering to be done there.

Keep in mind too, that pumped storage is quite inefficient. It's been too long
for me to even guess at a number but I remember being impressed by how low it
is.  It is simply the only thing we have right now that scales to that size.
That's why I'm cautiously excited about the NaS battery developments.  It'll
be awhile before gigawatt-hour scale batteries are possible but they're
coming.

Maybe they'll turn out to be so inexpensive and reliable that they can be
stationed in neighborhoods or even at houses for peak load shaving, presenting
the utility with a uniform load across the day.  The most expensive thing in
the battery is the vacuum-insulated container and great progress is being made
to reduce those manufacturing costs.  It's just a matter of manufacturing
engineering and not dependence on any technology breakthrough.

Personally, I want a set for my MH.  In the space where I have 500 ah of lead,
I could probably put 2500 ah of NaS batteries.  I could run my AC for days on
battery power :-)  In a few years....

John