Re: The Physics Behind the Spanish Blackout

On 14/06/2025 3:27 am, john larkin wrote:

On Fri, 13 Jun 2025 16:46:19 +0100, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:
 

Bill Sloman <bill.sloman@ieee.org> wrote:
>

On 13/06/2025 11:02 pm, Liz Tuddenham wrote:

Don Y <blockedofcourse@foo.invalid> wrote:

<snip>

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.

>
Why bother? Storing the power in a "power wall" style battery does
exactly the same job, with fewer intermediate stages to waste power
along the way.

>
The storage of energy (in this case below ambient) in a tank of water is
a lot less environmentally damaging than batteries of any kind and
water-cooled air conditioning is more efficient than air-cooled.

 Water is great stuff. It's cheap and has a huge specific heat.
 Imagine two tanks and a heat pump between. Heat one tank and cool the
other.

Why not just store the power in a battery and use it to drive the heat pump in the air-conditioner when you need it. It's cheaper than finding space for two tanks and  buying and installing them, and it's thermodynamically more nearly optimal.

Electricity will need to get more expensive to make things like that
practical, but it will.

It won't ever be practical.

Probably the best long-term residential investment now is insulation
and white roofs.
 Maybe Sloman can describe his solar panels and batteries and his
electric car with grid storage.

I've still got the car that my wife an I bought back in 2011. It still works fine though I only take it out about once a week.
Our flat doesn't have any place to put solar panels. The owner's corporation may find some space the all residents can collectively exploit, but while people in Sydney are thinking about how that might work, it hasn't happened yet.
It strikes me as worth thinking about how I might exploit those possibilities when they become accessible, and I do seem to have enough spare processing power to be able to spend some of that way.
--
Bill Sloman, Sydney