Re: The Physics Behind the Spanish Blackout

On 6/13/2025 6:02 AM, Liz Tuddenham wrote:

Don Y <blockedofcourse@foo.invalid> wrote:
 

We have 6.5 useful solar hours.  Likely something like 10-4.  Peak usage
(for the utility) extends to 7P.  I.e., refrigeration is in high demand
for the entire "peak rate period" (my numbers trying to demonstrate that
7PM isn't anywhere near the point where you could consider NOT using
refrigeration -- so 3-7 most definitely would also have a heavy cooling
demand)

 Is there any way you could 'store cold' rather than electricity?  Use a
solar-powered heat pump during the hours of sunshine to cool a large
tank of water, then reverse the the pump , which could be powered by a
relatively small battery and inverter, to run water-cooled air
conditioning during darkness.  (A DC powered electric motor on the heat
pump might be even more efficient - just remember to replace the brushes
regularly.)
 That way you could take your biggest load off-grid entirely.

I've seen businesses that "make ice" during the off-hours to
lessen their refrigeration load during the peak hours.
But, it is a large investment.
The "cheap" way to cool is to use evaporative cooling.  But,
it really isn't much cheaper as you need to run the blower
continuously -- to push the humidified air OUT of the building
(failing to do so leaves you in a sticky soup!) -- as well as the
increased water consumption (we can always get more electricity;
but water is a scarce resource)
Getting rid of the heat -- in a useful way (besides just hoping it
dumps into the air) -- could be a help.  I've seen heat-exchangers
(placed with the compressor/condenser) that transfer the heat to
a nearby swimming pool.  But, once you have a few thousand gallons
of HOT pool water, *then* what?
[Swimming in 110F water is an interesting experience.]
The smarter move would be to demolish the house and build one that
is inherently more energy efficient.  E.g., move a fair bit of
the living space below grade (soil temperature is ~70F year round).
Install a ground-sourced heat pump, etc.