Green Energy, and the German Grid, from: Kiev Is Burning

[BansheeOne]

Yeah, gas prices are given per MWh.

[rmgill]

On 7/3/2023 at 4:31 PM, sunday said:

We have one of those peak hydropower plants not far from Barcelona. When visiting it, it was not rare to see the turbines start several times in a few hours, and that was before the massive installation of renewables.

A nice thing about hyrdo is the short time to respond to demand. 

[sunday]

9 minutes ago, rmgill said:

A nice thing about hyrdo is the short time to respond to demand. 

I think it is only some hydro, not all of the hydro power plants, but I am not sure about that.

[rmgill]

Hmm. I’m curious about the spool up time complexities with hydro. With a plant that needs to boil water, you have to wait for the kettle to heat as it were. Unless you’re keeping it warm and on standby as it were. 

Edited July 22, 2023 by rmgill

[sunday]

2 minutes ago, rmgill said:

Hmm. I’m curious about the spool up time complexities if hydro. With a plant that needs to boil water, you have to wait for the kettle to heat as it were. Unless you’re keeping it warm and on standby as it were. 

No, that should not be the major problem. Hydro turbines are comparatively slow machines, driving generators  that have a high number of poles.

Problem is water hammer when one wants to stop the generation. That problem could be more important in power plants operating at high heights/low flow rate.

[rmgill]

Stopping would be spin down though no? Sounds like its mainly a matter of throttling and feed back on water hammer. I can see why it would not be instant on of off, but its faster than boiling the kettle. 

[sunday]

16 minutes ago, rmgill said:

Stopping would be spin down though no? Sounds like its mainly a matter of throttling and feed back on water hammer. I can see why it would not be instant on of off, but its faster than boiling the kettle. 

No, one needs to cut the flow of water, and dampen the inertia of the liquid column in some form, usually using a surge tank or a surge chimney. Found this nice video of a surge chimney receiving the water that could not go to the turbine once the respective valve was close. Quite impressive.

Also, some class video with the theory:

 

[Colin]

12 hours ago, BansheeOne said:

Yeah, gas prices are given per MWh.

We call petrol gas, hence the confusion

[DB]

Don't forget that between steam turbines and water turbines, there's also gas turbines. No kettle to boil there.

[sunday]

25 minutes ago, DB said:

Don't forget that between steam turbines and water turbines, there's also gas turbines. No kettle to boil there.

Yes, those and some hydro are the preferred peak power plants. Note that combined cycle plants could also work as gas turbine only plants, too.

[rmgill]

3 hours ago, DB said:

Don't forget that between steam turbines and water turbines, there's also gas turbines. No kettle to boil there.

True. Those do start up faster. 

[urbanoid]

On 7/22/2023 at 12:40 AM, sunday said:

I think natural gas is usually priced by energy units, i.e. €/kWh, €/MWh, $/MBTU, etc., as the heating power of a unit of volume at standard pressure could vary according to the composition of the gas.

Sometimes by volume too, saw plenty of articles with prices for 1000m3.

[BansheeOne]

14 hours ago, Colin said:

We call petrol gas, hence the confusion

Ah, I thought it was pretty clear from the thread topic. No, the gas that goes into cars is a little under two Euro per liter, depending upon sort.

[sunday]

1 hour ago, urbanoid said:

Sometimes by volume too, saw plenty of articles with prices for 1000m3.

Could be thus in some markets, yes.

[JWB]

New nuclear reactor enters commercial operation, first in US in 30 years (msn.com)

[sunday]

Good!

[urbanoid]

Several hundred more and I think they're set, eh? 

[sunday]

Let's see...

A 1,000MW NPP generates in a year 1,000 x 365 x 24 x 0.95 = 8,322GWh = 8.3TWh for short

Electricity consumption of Georgia in a year is: 131 TWh (4% total U.S.) Currently 28% of that energy is nuke-generated.

So several dozen more, I would say.

[urbanoid]

From what I found US electricity consumption was ~4100 TWh in 2022. And the population is still growing and will likely continue to grow, which means energy consumption also will. And if the US wanted to really reindustrialize... also a bit of a wild ass guess, but IIRC Elon once said that if the US wanted to move on to electric cars the capacity should be ~doubled.

[sunday]

Ok, about five hundred of the 1,000MW ones, so you were closer to the truth. There are NPP of more power, both because reactors are more powerful and having several reactors in the same site, like the famous Zaporizhzhia power plant.

Electric cars are not only a problem of generation, they are a problem also for transport and distribution.

Edited July 31, 2023 by sunday

[PCallahan]

6 hours ago, sunday said:

Ok, about five hundred of the 1,000MW ones, so you were closer to the truth. There are NPP of more power, both because reactors are more powerful and having several reactors in the same site, like the famous Zaporizhzhia power plant.

Electric cars are not only a problem of generation, they are a problem also for transport and distribution.

Hey, Plant Vogtle's 4th reactor should go online next year... so that's, at least a bit, of a start. Well, not much of one really.

[seahawk]

https://internationalbanker.com/finance/will-germany-remain-in-a-recession-for-long/

Germany's economy doing worse than Russia. Go green energy.

[Ssnake]

10 hours ago, urbanoid said:

... Elon once said that if the US wanted to move on to electric cars the capacity should be ~doubled.

For reasons unknown, my previous reply disappeared, so one more attempt; #1, upgrading the grid is certainly going to be a major infrastructure investment (and I'm not quite as optimistic as Mrs Hossenfelder that it's really going to help bring down CO2 emissions, given the rather long-distance break-even points of electric cars):

 

Similarly, this Tesla Solar Roof user discovered that charging his car cost vastly more electricity than keeping the air conditioning on (the #2 electricity drain). But, for a mere 120,000 USD investment he got rid of his monthly $180 utility bill, so it'll break even in just ten years (provided nothing breaks and needs replacement):

 

[urbanoid]

I have doubts about electric cars myself, far more than our betters seem to have, both in the US end the EU. But since both are either making or planning new laws banning the sales of new petrol and diesel engines care in 2030s, the electric ones are about the only alternative for now. Yeah, I know, hydrogen, there are whole two models on the market at the moment and the sales aren't impressive.

[sunday]

6 minutes ago, urbanoid said:

I have doubts about electric cars myself, far more than our betters seem to have, both in the US end the EU. But since both are either making or planning new laws banning the sales of new petrol and diesel engines care in 2030s, the electric ones are about the only alternative for now. Yeah, I know, hydrogen, there are whole two models on the market at the moment and the sales aren't impressive.

One legislates against Nature at his own risk, and Nature always wins.

See the story of King Canute and the tide.