Re: Grand Apagon - Electricity (not) in Spain

On 4/30/2025 12:45 AM, Jeff Layman wrote:

On 30/04/2025 01:07, Don Y wrote:

Or, just solar "farms"?

>
They can drop out entire blocks of switchgear to take a given region or zone
offline (as would happen if a fault condition trips a breaker).
>
The big problem on a really sunny day is that an individual house roof 4kW PV
installation in late afternoon in the UK will be potentially exporting all of
it to the grid. That is about 20-30 houses worth of electricity for each solar
roof.

>
Huh?  A single residential PV is enough to *power* 20 homes?
A 4-5KW installation would barely cover the home on which
it was sited.
>
E.g., our "average" (24/7) load is about 1KW.  Of course, that
neglects the peaks that we see OFTEN throughout the daylight
hours (night load is relatively small -- a few LED lights
plus my computers)
>

They drop say 100MW of load or approx 500k houses @ 200W but with 2% of them
generating 4kW then they also drop off 40MW of local generation.

>
The 200W figure is mystifying.

 In the UK air-conditioning is not common, although it is being used more as the climate heats up. On a bright day with solar power producing pretty much full output, most of it will not be used.

Peak demand (local provider) today was 1GW.  Less than half of that satisfied
by the utility's solar and wind farms.
And, it's cooled to ~28C -- about 10-12C cooler than normal for this
time of year.
Come "summer" (next month), demand will double but solar+wind will only cover
that same 500MW (for 12 of the hours in the day).
This is exclusive of customer-owned facilities.

An average house might only be using low hundreds of watts - perhaps 60W for a TV, 40W for a laptop (maybe double for a desktop), perhaps an intermittent 100W for a fridge/freezer (I have no idea what the average consumption would be as it would depend on how much the doors are opened!), a few watts for assorted wallwarts, no lighting required during the day, and cooking probably using gas. Even if a microwave is used, you're probably looking at 1.5kW for only 5 or 10 minutes.

The average (local) monthly electric bill is ~$130 (128)  If you guesstimate
price per KWHr as $0.16 this translates to ~800KWHr / month or ~1.1KW/hr
(other sources claim this to be closer to 1300KWHr/mo)

As it happens we are currently experiencing remarkable late April weather - about 10°C above normal (it will hit 26°C today) with full sunshine all day. It will peak tomorrow with possibly 29°C expected. Currently solar is providing about 10% of the UK power requirement (about 30GW - see <https://www.gridwatch.templar.co.uk/>).

We are 15F cooler than normal at ~80F.  We've already had our first 100F day.
Thankfully, we can keep the house cool by opening windows, overnight, when
the outdoor temperature drops to the high 50's (a 30 degree day-night delta
is pretty common; so, when daytime highs are up at 110F, night lows
will be 80F -- and, brick buildings will have already stored enough
heat to make them hard to cool, naturally)