This R4 news story about a solar eclipse potentially disrupting the electricity supply...

[MacB]

Something of nothing really, the question is just what happens if there's a power cut? The answer is, the same as any other power cut but at least this time we know exactly when power will come back on.

 

[jefmcg]

Something of nothing really, the question is just what happens if there's a power cut?

Well, yes, I guess, but I would expect power companies to prepare for an power cut they knew was coming. Wouldn't you?

 

[machew]

How does Germany cope when it's cloudy?

The thing is, when clouds cover the sun, the solar system doesn’t stop working producing power. It just reduces the output of energy. The thicker the clouds, the less power the system will produce. Yet when the sun shines through the clouds, solar panels still get direct sunlight plus light reflected from the clouds. Amazingly, you can get more solar energy out of a cloudy day than a sunny one!
When the moon goes in front of the sun, there is no power produced

 

[jefmcg]

A few years ago we visited the "Hollow Mountain" in Scotland. It's a hydroelectric energy storage facility built inside a mountain like some kind of Bond villain's lair. When there's spare capacity in the electricity network, usually at night, they use it to pump water up into the reservoir. Then at peak times they can use that stored energy to drive the turbines. So it smooths out fluctuations in supply and demand.

I reckon it could cope with a solar eclipse.

Sure, but again, if you have all the data, model the eclipse you are expecting and be sure. And if it's not looking good, plan for the outage.

My fingers are crossed for Elon Musk to give us a better battery.

 

[jefmcg]

The thing is, when clouds cover the sun, the solar system doesn’t stop working producing power. It just reduces the output of energy. The thicker the clouds, the less power the system will produce. Yet when the sun shines through the clouds, solar panels still get direct sunlight plus light reflected from the clouds. Amazingly, you can get more solar energy out of a cloudy day than a sunny one!
When the moon goes in front of the sun, there is no power produced

Excellent point.

My full solar eclipse, the birds sang their good night songs, and the jasmine let off it's evening odour. This did not happen during a thunderstorm.

 

[Drago]

The street light outside my house produces a solid 37W on my panels.

 

[winjim]

The street light outside my house produces a solid 37W on my panels.

I think you win the prize for least efficient energy conversion system.

 

[classic33]

I'm sure it's entirely feasible for a country the size of Germany to be blanketed in cloud... just google pictures of the earth from space.

View attachment 367935

...and let's not forget, the penumbra of an eclipse moves a lot quicker than a weather system.

 

[Wobblers]

Well, yes, I guess, but I would expect power companies to prepare for an power cut they knew was coming. Wouldn't you?

They do. Large energy users (usually things like aluminium refineries or chlorine plants) are usually on contracts where their supply can be cut off at something like 30 minutes notice. Things like electric furnaces or large refrigeration plants aren't too fussed about losing supply for 10-20 minutes, so are often on frequency sensitive relays. When the grid struggles, the mains frequency decreases, causing those relays to open to decrease the load on the grid. Those customers get discounts to be on those sort of contracts.

Of course, they do tend to have a fair amount of reserve capacity from the likes of pumped storage, thermal plants - which I'm quite sure would be run up to provide "spinning reserve" in a case like this, or even hydro, which can increase its output in only a few minutes.@swansonj's the best person to ask about this as he works in the industry.

 

[swansonj]

....@swansonj's the best person to ask about this as he works in the industry.

We had a briefing note come through at work a few weeks ago about planning for the next eclipse. I had been reading this thread with avid interest (and a certain amount of despair - would people really prefer power companies not to plan ahead but just to suck it and see?) but I want to dig out that briefing before replying so that I can be deeply unfashionable and reply from a basis of knowledge of the current facts.

 

[Drago]

Did the briefing urge you to sacrifice a virgin to please the angry Sun God?

 

[Profpointy]

There was the story about the explorers captured by the cannibal tribe and about to be cooked and eaten. The explorers were there to observe an eclipse that very afternoon, so the leader of the expedition works out a cunning ruse to frighten the cannibal chief. "If you don't set us free I will call upon the Gods to shut off the sun, then you and your tribe will be in darkness". He explains to his friends that when the sky starts to darken, the cannibals will likely beg for deliverance and with any luck we'll be loaded up with treasure as well as being set free. The cannibal chief replies that ordinarily they'd have been set free but "we're having a feast to celebrate the eclipse"