Intermittency is a tough thing to handle. The US uses 12,000 GWh of electricity per day. The word used 60,000 GWh per day. Evening out daily fluctuations, let alone seasonal fluctuations, demands an enormous amount of storage.
https://reneweconomy.com.au/much-storage-needed-solar-wind-p...
Sadly, there's far, far, far too much FUD floating around about storage (understandably, coz wind+solar threatens the nuclear+carbon lobbies), and not enough thorough and realistic studies like this one.
I've heard people say "oh you cant pay attention to this study because it's in Australia which must be discounted because [reasons], what about [ other country ]?", and I'd welcome seeing an alternative study making appropriate assumptions, but none of these comments so far come attached to anything other than FUD.
I've also seen far, far too many people build or cite a "naive" models that make inappropriate assumptions (e.g. that zero power is generated at night by wind).
So a study for Australia should be applicable everywhere else? Like in Germany or Norway?
I am, as I said, still waiting for models which demonstrate that it is wildly different...
Here's a good overview article: https://energytransition.org/2017/07/germanys-worse-case-sce...
> Germany will always need dispatchability roughly at the level of its annual peak demand
The solution they're proposing is power-to-gas. Which so far has been way too expensive to matter.
Power to gas for the "worst case scenarios" would also be the last thing you'd do to transition a grid from 97% carbon free to 100% carbon free.
The issue is that electrical grids have very high reliability requirements (upwards of 99.95%). Plenty of models claiming that small amounts of storage required neglect to mention how frequently they will encounter insufficient generation. Remember, even fulfilling demand 99% of the time is a 20x increase in blackouts.
Also, even just 12 hours of storage globally would be 30,000 GWh of storage. That's still about 50 times the amount of batteries produced annually. The reality is that hydropower is the only feasible form of grid storage.
> However, the share of solar generation increases less, or even decreases, in higher-latitude countries like Russia, Canada, and Germany (Fig. 2b). These trends continue as more storage is added, so that with 12 h of energy storage and no excess annual generation, 83–94% (average 90%) of electricity demand is met with mixes of 10–70% solar power (49% on average; Fig. 2c).
Even with 12 hours of storage, Germany would be seeing blackouts weekly.
To put this in perspective:
> reliability standards in industrialized countries are typically very high (e.g., targeting <2–3 h of unplanned outages per year, or ~99.97%). Resource adequacy planning standards for “1-in-10” are also high: in North America (BAL-502-RF-03), generating resources must be adequate to provide no more than 1 day of unmet electricity demand—or in some cases 1 loss of load event—in 10 years (i.e., 99.97% or 99.99%, respectively)
So no, even with 12 hours of storage and 50% overcapacity, we'd have an unacceptably unreliable grid.
Also, your linked article is not modelling a carbon-free grid:
> Graham says that the CSIRO modelling showed that at very high levels of wind and solar, a maximum of half a day’s average demand was needed for storage. In some areas of the grid, only around three hours might be needed.
What are these "very high levels of wind and solar"? How much of the remaining demand is satisfied by fossil fuels? The article doesn't say.
If we hope to go 100% renewable, storage is a key piece of that puzzle.
Much of the pumped hydro that exists today was built to handle excess nuclear.
Furthermore, too much energy is a far easier problem to solve than too little energy. People can desalinate water, or do any other energy intensive things.
Economically? Load following with nuclear power means an even worse business case than running at 100% 24/7. And nuclear power is already a laughably bad business case when running at 100%.
Economically? Load following with nuclear power means an even worse business case than running at 100% 24/7. And nuclear power is already a laughably bad business case when running at 100%.
Nuclear is a bad business case compared to a fossil fuel grid. Solar and wind backed by fossil fuels are a better business choice, too. But when it comes to a fossil-fuel free grid, it's the only viable option if you don't have a big source of hydropower nearby. Batteries can't deliver the required storage capacity. Remember, the world uses 60,000 GWh of electricity per day. And as transportation and industrial uses of fossil fuels are electrified, that'll increase.
Hydroelectric storage is the only grid-scale energy storage system available to us, and it's geographically dependent. And the places that are suitable for hydroelectric storage usually don't need it because they can just generate electricity via hydropower anyway. Until your hypothetical breakthrough in power-to-gas or giant flywheels actually happens, this is the state of grid storage.
You have a baseload. That's basically the minimum load that always exists. You don't have to worry about selling the power, it's already sold. And then you have peak. Both of these are time / weather dependent but we're still quite able to plan days, if not weeks and months, in advance for what those two values will be. As an example, let's get back to the original topic of the article.
If you're Google and you have a particular datacenter at a location, you know what that baseload is. You know what the peak is. It's a pretty simple calculation to figure out what is most cost-effective here. It's probably even easier for you than the local power company, as base and peak loads likely don't fluctuate much for you outside of HVAC keeping up with weather. It might be to use nuclear for just base load and use the local grid for the rest. It might be to over-produce occasionally because that's still cheaper than buying from the local system operator. Hell, you can probably sell any access, but that's more of a problem than most people think.
But the point is nuclear is king when it comes to baseload power supply. And a datacenter, which consumes a lot of power consistently, is almost entirely baseload.
And power plants having individual finances in the first place is a policy choice, not a law of nature.
If you find cryptocurrency mining objectionable for some reason, you could apply the same basic principle to things like aluminum refining or desalination.