Saturday, 9 March 2019

Just 5 windless days, in a 100% wind and solar UK, would cost £1,164 billion in Battery Backup - 83X more than CCGTs.

The UK uses 340 TWh of electricity each year.
Can this ever be supplied by 100% wind and solar power with battery backup?

Because we generally deplore landscape scenic desecration, a 'reasonable' scenario might be:
30% onshore wind-43,120 MW installed capacity (currently - 12,851 MW) 
60% offshore wind - 60,800 MW installed capacity (currently - 7,899 MW)
10% solar - 37,800 MW installed capacity (currently - 13,060 MW) 

Taking a random 5 days at the end of February 2019, when the wind 'disappeared' but was compensated for by some decent levels of solar power, this is the metered data:

12,851 MW of onshore wind generated 974 MW; 43,120 MW would generate 3,268 MW
7,899 MW of offshore wind generated 864 MW; 60,800 MW would generate 6,650 MW
13,060 MW of solar generated 1425 MW; 37,800 MW would generate 4,124 MW

Shortfall from 100% wind and solar = 33,197 - 3,268 - 6,650 - 4,124 = 19,155 MW

Over the 120 hour period, battery backup required = 19,155 x 120 = 2,298,600 MWh

"...[T]he Australian government announced that it would invest $25m (£13.5m) .... to fund large-scale grid-connected batteries, together providing....some 80MWh of energy storage...": Equivalent to £168,750/MWh. 

Cost of batteries to generate 2,298,600 MWh @ £168,750/MWh = £388 billion.

CCGT backup to supply 2,298,600 MWh would be £14 billion 

But batteries only last 10 years. To generate for the 30 year lifespan of CCGTs would cost: £1,164 billion.

Battery backup costs 83X more than CCGT backup!



James38 said...

Well done. Excellent maths showing absurdity of wind/solar/battery concept.

See Moltex Energy for what may be the best modern Molten Salt Reactor design yet. They are on schedule to build a commercial reactor in Newfoundland.

Moltex is a British company. I would like to see a discussion of the various types of modern reactors. It seems that a lot of expensive duplication of effort might be avoidable if we start a more comprehensive analysis on a global level.

In cases where no obvious preference could be discovered by discussion, pilot projects could be built with the express purpose of deciding which design is most economical for widespread deployment.

James38 said...

Thorcon Power is another adaptation of molten salt reactor design. They also are working on a potential commercial project in Indonesia. Moltex and Thorcon are very different designs with the same intent, and provide a fascinating extension of the ideas I expressed in my first post.

There really is no need to continue building two or more different types of reactors with the same intent of producing grid level power. It would be more efficient to settle on the most economical design and get everyone on board building and refining that design.

Then it would be truly exciting to see someone come up with yet another better design. Let's have some fun saving the planet.

James38 said...

I just looked up the BWRX 300. It is a GE/Hitachi BWR (Boiling Water Reactor) aka PWR (Pressurized Water Reactor). While it is a good new design, with Passive cooling: (steam condensation and gravity allow BWRX-300 to cool itself for a minimum of 7 days without power or operator action) it still operates under pressure which complicates construction, using a lot more cement even if this design is far superior to previous ones.

Again I say check Moltex Energy for a superior reactor design. The Molten Salt Reactor operates at atmospheric pressure, and needs no high pressure reaction vessel or containment structure. Since the MSR uses no water in the reactor, it avoids corrosion and safety concerns inherent in PWR. The MSR has even lower construction costs and uses less concrete.

It seems to me that the Moltex design is the winner in competition with the BWRX 300. Recommend reading the Moltex Energy site.