This particular proposal is based on the idea that if renewables are cheap and getting cheaper (which they are) then you should build a lot of them.
They claim the lowest cost model for generating 100% renewable involves 5x the capacity being built.
However, they recommend rolling out 12x because that would provide another 500Twh of energy for only a 20% increase in spend (while reducing the amount of battery needed by 50%). A concept they have cheesily named "superpower".
While nuclear is one of the most expensive electricity sources, with surprisingly limited fuel reserves given the energy density, it's incredibly safe (despite the reputation) and I think there is inherent value in a diverse supply that can make up for the sticker price.
Also, China is able to build it at a reasonable price (~$40/MWh). It's not destined to be expensive, the price is just a consequence of excessive safety precautions.
Note that this article says could not will, so I’ll answer a related question of yours that better reflects the article:
> How could they deal with variability of all these renewables?
I’m guessing a mix of pumped hydro, purchased hydro and nuclear, home storage, robust grid, increased energy efficiency, smarter usage periods for heavy users such as industry or EV charging, etc. And then there is emerging technologies such as on-site carbon capturing of natural gas power plants, liquid metal/molten salt batteries capable of robust large scale grid storage, etc.
Solutions do exist, and no one of them will solve it for all, but together they will.
A large variety of places, but not by replacing 100% of electricity and only electricity in one region at a time.
You replace 30% of electricity. That's easy.
Then you replace a bunch of dispatchable non electric loads and use the times the new generation can produce electricity to replace another 20.
Then you add a bunch of 4 hour storage and dirt cheap thermal storage. You get another 20.
Then if there's finally a breeder reactor it can join the party, otherwise you round out the rest with storage as the price plummets. Burner reactors are irrelevant.
I feel like variability we can engineer around. What I’m more concerned about as someone generally pro wind/solar is how we’re going to discover and build supply chains for all the extra materials we need for this transition. We need a renaissance in resource exploration, discovery and extraction.
They actually rule that out in their model. It should make things slightly cheaper and easier if the EU nations all do this and trade energy, but it's not required.
They exclude a few other notable things:
> Our limit scenario makes a number of severely constraining assumptions
for the purpose of emphasizing what is possible for 100% SWB systems.
The bar for clean energy will not be nearly so high in most locations.
Assumption 2: no conventional operating reserve
Assumption 3: no other renewables
Assumption 4: no distributed generation or storage
Assumption 5: no impacts from electric vehicle energy storage
Assumption 6: no demand response, load shifting, energy arbitrage,
or peak shaving
Assumption 7: no technology breakthroughs
Assumption 8:
no subsidies, carbon taxes, or other financial innovations
These are all good things, they're not predicting or recommending against them, they're just saying they've assumed they don't exist when running the numbers to prove it would work everywhere.
I used to think about this as being a problem, but more and more I'm wondering if this is the wrong way to think about renewable capacity? For comparison, for years ISPs have been saying "what would you do with 1 gbps internet speeds?" And they've been putting of making the change to that because it's difficult. I think sometimes the problems that we expect to happen are a lot harder to be certain of when we're entirely speculating.
I bet some of this would sort itself out if they had sufficient renewables, and that the rest would be an easier incremental problem if they made the switch.
Well-known? French nuclear reactors are doing load following every day.
What nuclear energy is bad at is as a backup for renewable energy when there is no wind. Because nuclear costs the same whether you use it or not, so you pay for an energy source you don't use most of the time so that you can use wind instead. If you use nuclear, scrap wind.
Nuclear should be heavily subsidized regardless. Whenever they aren't needed for immediate demand, these power plants can be put to use for so many other tasks: desalination of water, energy storage in terms of hydroelectric pumping, direct carbon capture. Chemical fuel creation (hydrogen, ammonia, methanol, methane, etc).
If we want to unscrew ourselves of the ticking time bomb we set, we need all the "clean" energy we can get, and then some. Nuclear is potentially an existential requirement to the mix.
Synthesize and bottle carbon-neutral fuels like hydrogen or methanol with surplus off-peak nuclear power. Use fuels for peak on-demand electric, transport, etc.; methanol burns in standard internal combustion engines. Solves both the variable output and battery problem. Cost isn't too pleasant, but it scales and all the tech for this cycle exists now.
Pumped hydro is the obvious answer here, and today accounts for by far the majority of stored renewable electricity. There are geographies in Germany (natural and artificial) that can easily accommodate a lot more pumped hydro.
Second option (and also a boring one) is distributed home storage using traditional led-acid or lithium-ion batteries. This is already rolled out and can be increased to scale pretty easily.
A more exciting answer is liquid metal (or molten salt) batteries that works as large scale grid storage by heating the batteries elements (Calcium and Antimony) to very high temperature that keeps them separated while charged slowly mixing into a new liquid alloy as it discharges. You can read more about the technology here https://ambri.com/technology/ However I think before 2035 this will at best be a distant third from the two (boring) storage options above.
(but my understanding is that there are many other battery technologies in development that work too, e.g. older chemistries and/or mechanical/gravity/heat batteries)
But with the other logic, oil is not an energy source either, it is rather an energy storage that just so happened to store energy created by the sun millions of years ago.
I think it is OK to be loose on the technicalities in this instance, we all know what was meant.
Why do you think that's a useful question? Policy proposals like this are at the level of encouraging people to make fast-tracks for investments and passing planning permission for the factories to build the batteries and the mines to get their feedstocks; governments aren't generally even in the business of directly building the power stations themselves.
> Only realistic path is nuclear, but it'll take longer than 2035.
Not enough fissile fuel[0] for everyone to do that at western usage levels. And if you're talking that long, you can reasonably build out a global power grid, switching people from mining coal to mining metals, and the cost of making a grid of that scale is about the same (at current metal prices) as we currently spend per year on fossil fuels, give or take a factor of two.
[0] or at least, accessible fissile fuel; if you want to filter the oceans you get all the lithium you could want (and more other goodies like phosphate) as well as the uranium.
They claim the lowest cost model for generating 100% renewable involves 5x the capacity being built.
However, they recommend rolling out 12x because that would provide another 500Twh of energy for only a 20% increase in spend (while reducing the amount of battery needed by 50%). A concept they have cheesily named "superpower".
See the table at the bottom of page 4:
https://static1.squarespace.com/static/585c3439be65942f022bb...