Nobody is seriously investing in storage, nobody is working on the problem of continental scale grid interconnection. And these are not problems that can be solved quickly as they come up, - Utility scale storage means rockworks!

Demand-side management can be rolled out faster than supply-side management, mostly because there's so much low-hanging fruit. Ammonia synthesis for fertiliser and synthetic fuels can be shuffled around without too much hassle, and to the extent electric cars achieve meaningful penetration in the transport infrastructure you'll have a few GWh of capacity at all points except the morning and evening commutes for the cost of hooking up your chargers to the internet and writing a bit of software. There's a ceiling to how much demand flexibility you can get, but it gives enough time to start with the rockwork.

That aside, nuclear suffers from precisely the same problem, unless you propose to load balance with spinning reserves. Which you can do, in the same way you can load balance a wind-only grid by detuning turbines to varying degrees. But that's a silly way to load-balance.

- Jake

Friends come and go. Enemies accumulate.

It is a problem that shows up at 20% - if you have enough renewables to supply a fifth of all the kwh's you consume, then when high output and low consumption coincide, 100% of your current electricity production is renewable, and all else must be shut down.

Not really - this would be true if your 20% of renewables were all from one wind farm in one location. The reality is that, as noted, you have many different renewables with different production profiles (not to mention that demand itself is not flat over the day, so "100% of average demand" is actually much less than actual demand a lot of the time) - and even within wind you have different production regimes and thus it is actually quite hard to reach 100% capacity at any time in a wind system - and the larger your sample, the harder that gets.

Now, taking into account existing hydro storage, the difference between solar and wind, the fact that offshore wind is at 40% capacity factor with a production profile closer to that of demand, and so forth, and you get a much higher threshold...

Guess what: Germany is at 20% this year, and as far as I can tell, there were no big tensions in the system...

The vision most people here have of the future grid is one in which at least 90% of all electricity production is low carbon, and supply and demand is managed via a supergrid, storage and demand managment. This is a fair description, yes?

I don't know about 90% myself, but, yes, significantly above 50% should be a target for the next 20 years (in my case, but maybe I'm a minority there, I would not mind keeping a decent chunk of nuclear as base load).
And once this is achieved, we'll have much better visibility on what needs to be done for the rest. Why make that plan today when we don't have all the info?

Nobody is seriously investing in storage, nobody is working on the problem of continental scale grid interconnection.

That's simply not true. The EU has been busily pushing for grid integration and development of pan-European networks (not just for electricity), and the wind and solar industry are the biggest promoters of initiatives like the super grid or desertec. The unbundling of networks pushed by the EU is now almost complete and one does see that independent grid operators are much less hostile to renewable than their former utility owners, who were conflicted in that respect, and grid development is certainly happening more easily when the investor the grid company) is not the main obstacle...

And one other big shoe will be moving private transport to the grid, which will have a major positive impact on the reduction of our fossil fuel consumption as well.

Wind power

There is, of course, nothing wrong with 100% of power coming from a single wind resource and having everything else shut down.

Indeed, consider what happens if that gets pushed above 20%. At times, energy is available to be produced but not sold because the available harvest is above total energy requirement. That's cheap power, available to neighboring countries who can build the UHVDC grid to grid transmission to go fetch it.

And we want that.

And of course as the UHVDC grid to grid electricity superhighways are built, the volatility of the energy portfolio are reduced, since they can import during slow volatile renewable power production periods as well as export during high volatile renewable power production periods.

And we want that.

So, where's the problem? It seems the critique of the feed-in tariff system is that there are other policies that also ought to be in place, and if they were in place the whole transition would go more smoothly. Its hard to see why that critique would lead to abandonment of the feed-in tariff system.


I've been accused of being a Marxist, yet while Harpo's my favourite, it's Groucho I'm always quoting. Odd, that.

I would be much obliged, my mail is johnatlarge (arobase) gmail (dot) com.

Thank you for this discussion and the one in the french presidential primer diary Jérôme posted.

The Hun is always either at your throat or at your feet. Winston Churchill

I would suggest that anyone with more than a passing interest in this topic might consider gaining access to the IEEE Power and Energy Society. (Probably at your local university library.) Most of the publications are behind paywalls, but at least some material can be obtained at their website http://www.ieee-pes.org/

The reason I suggest this is that the membership of this society, made up of academics and practicing engineers, is really in the best place to consider and communicate the technical aspects of power generation, distribution, and management. They don't talk about politics much, though.

Regarding storage, obviously you need something like pumped storage, which is limited by geography and environmental considerations, or lots and lots of batteries. Batteries are expensive, so how do you get people to buy them? By putting them in cars, which are a consumer product that has 100 years of demonstrated demand, an outrageously short capital replacement cycle, and a price point that is tremendously skewed from what would be considered sensible in an objective analysis. Namely, people are willing to blow tons of money on cars when they could take the bus for a lot less money.

Plug-in hybrids and electric cars are all about energy storage, and they are serious, and there is a lot of investment.