Solar Is Cheapest Electricity in History, U.S. DOE Aims to Cut Costs 60% by 2030

Cynics always talk about the amount of energy storage required for solar as if you need to store 24 hours of energy for solar/wind to be viable.

I'd like to see numbers on having 1 hour of storage for peak demand, a robust national grid, and appropriately provisioned and placed solar and wind, taking the duck curve into consideration.

Realistically we should saturate daytime energy demand with solar, and if there aren't any scalable storage options by then switch gears and proceed with hydroelectric where it's viable and nuclear where it's not.

... so if we could increase battery production by just 10x, then we could create an hours worth of storage every year. That seems... very doable.

What's the point of this comparison?

Lithium ion batteries are probably the least cost effective means of dealing with intermittency. It's also rare that the entire world is without wind and sun simultaneously.

In terms of cost:

Demand shaping < overproduction < pumped storage < < lithium ion batteries

Europe didn't want to act when russia invaded crimea, because russia supplied all the gas. Being dependent on your neighbors for your electricity supply and having no backup would only make this problem worse.

I would imagine the approach to store the energy would be to use the energy from solar panels to do work that can be used to produce electricity later.

For example, you could use solar energy to pump water back uphill to flow down through a hydro electric dam later.

Even if it isn't the most efficient, in the long run it would likely provide the best scalability and least long term environmental impact. Once you have the facility in place, the same water could be pumped uphill to flow back down a million times over with the only overhead replacing water lost through evaporation and maintaining the facility.

Am I missing something that makes such an approach unfeasible?

And this will increase a hundredfold to make EV production possible.

That means that if 10% of production goes to stationary storage then within 10 years, we'll have 10 full global hours of storage.

If there's serious demand then the supply will scale up to create it.

Also, old EV batteries will provide plenty of extra stationary storage. Not to mention batteries still in EVs, in a pinch.

Realistically we won't throw insane amounts of storage at the problem. We'll make demand more flexible so it does work when electricity is cheap and eases off when it becomes more expensive.

For instance, something like heating: why store the electricity for heating? Wouldn't it make more sense for a house to have some form of heavily-insulated thermal mass that it can massively heat when electricity is dirt cheap, then tap into at midnight without drawing power? Storing heat is cheap, you just need a giant block of concrete with solid insulation. You don't need fancy nanoscale tech like with lithium-ion.

Even something like a kettle: the hot water taps you see at companies that are pre-heated. Have a home-version. Insulate the shit out of that and do 90% of the boiling with peak electricity.

And that's not even touching industrial power usage.

Trying to ape past systems that were based on flat electricity prices just seems like a failure of imagination. Of course it would be expensive, but why the heck would you even want to?

If we actually deploy 50 GWh of hydrogen storage, and demonstrate that it can cheaply and reliability be built at scale then your point would be valid. But until then, hydrogen represents a theoretical solution not an actual solution.

It's existing technology, but it's a novel application of that technology. We haven't used hydrogen electrolysis as a form of grid storage before. And we certainly haven't used it for grid storage at the Terawatt hour scale. And that the scale we'll need to make wind and solar viable. 1 TWh isn't even 30 minutes of global electricity consumption.

Overproduction helps but doesn't eliminate intermittency. And pumped hydroelectricity is geographically dependent. The irony is that most places with extensive hydroelectric storage potential don't need wind and solar in the first place because they get their energy from hydroelectric generation.

We both know the answer: there aren't any.

Back in the 1950s people thought nuclear power would be cheaper than fossil fuels. They thought it'd be effectively free. The energy density of uranium is so much better, so clearly generating electricity with it would be much cheaper. But actually deploying a technology at scale reveals more and more challenges.

Your proposal for hydrogen storage is in the same phase that nuclear power was in during the 1950s. A solution that exists on paper, but one that hasn't actually encountered and overcome the challenges of implementing it at scale. Same with thermal batteries, synthetic methane, and so on. These are proposals that haven't passed the test of actual implementation at scale.

https://en.wikipedia.org/wiki/Storage_heater

Yes, someone could use more of it than we could supply. But they don't. The existing supply is sufficient to meet demand. And when demand changes, we are capable of increasing supply.

As we recently saw with Texas’ catastrophic fossil fuel production failures the big problem is not the source but poor management and not being able to get help from the neighbors.

https://en.m.wikipedia.org/wiki/Flow_battery

The main point I was going for is that we shouldn't think of a national network in the same way as we think of a off grid house with solar, where you have to deal with many hours without sunlight, and have storage capacity for several days of rain.

In a similar vein, the intermittency of solar and wind look bad when you look at isolated generation instances, but when you have a continent spanning network, the intermittency is reduced as the wind is always blowing somewhere, and the sun is shining for many more hours than when you look at any single point on map.

Again, I would love to see the numbers if you were plan out a realistic build out of this ideal network. It would probably be a pretty big number, but how would it compare to building out with nuclear, or even just lots of coal power plants from scratch.

We could easily have Petawatt-hour scale hydrogen energy storage.

You might expect roof top panels with sub-optimal orientation to generate about 12.5% of their peak rating when averaged over a year. That would be 375 watts, annualized, from a system with a peak capacity of 3000 watts. There is no van-portable battery system currently on the market that can store 375 * 24 * 23 = 207,000 watt-hours. (For comparison, the Tesla Model S battery stores 100,000 watt-hours.)

My guess is that you are not correctly recalling how much solar capacity these vans have installed. When I Google for van life solar I get guides and kits referencing much less power.

For example, this guide:

https://www.genericvan.life/2018/04/30/complete-vanlife-sola...

uses a single 150 watt panel. Based on the photo the article includes, I don't think that the van rooftop has room for more than 3 panels of this type.

Back in the 1950s people thought that nuclear power would be effectively free. But actually building it at scale exposed challenges of implementation that weren't foreseen. The cost of a system on paper and the cost after overcoming the challenges of actually building it are two very different things. For hydrogen storage, you only have the former.

Nuclear's problem are fundamentally political in nature. If we really cared about green energy, nuclear power could easily be built out at scale.

Nobody is arguing the solar and wind power isn’t cheap, but the cost of power on those cloudy windless weeks is going to be real high to make having all that standby generation around. It’s the cost to achieve the same reliability and 99% carbon free that is expensive.

Money is imaginary and global warming isn’t so let’s just print some bonds or move some numbers around in some database and build it all! - an electrical power engineer

The industries that manipulate tens of millions of tons of hydrogen each year would be astounded to hear this statement of yours. What are those facilities made of, unobtainium?

Hydrogen is being stored in a few places. That the storage isn't larger isn't because of any technical obstacles, it's because there's no reason to store it now. In particular, when we can burn natural gas without CO2 charges, using the hydrogen for energy storage is pointless.

This doesn't mean hydrogen CAN'T be stored, it just means the market conditions for widespread adoption of an off-the-self technology aren't there yet.

It seems that with all the interest in using ReBCO tape in tokomaks due to its ability to transmit more power at higher temperatures than the materials that preceded it (used, for example in ITER) that it could be used to transmit power over long distances. Has anyone actually done it yet, or is it just too expensive? (Apparently the current capacity of superconducting cable is finite; if you run too much current through it, it'll transition to becoming non-superconducting. So maybe the amount of ReBCO tape needed per unit of power or the amount of active cooling needed makes it impractical.)

Eventually, to be able to usefully transmit power from daytime sun to nighttime will require crossing oceans. Which I imagine would be tough to do with a cable has to be actively cooled and work for many years without maintenance. Maybe for my hypothetical North America to North Africa route, you'd run a superconducting cable down through Central and South America over to Brazil, then have a normal high-voltage DC line across the Atlantic, with another superconducting cable that crosses the Sahara.

Unfortunately, those alloys that experience embrittlement includes the ones used in steam turbines: https://www.sciencedirect.com/science/article/abs/pii/S09215...

And it certainly doesn't answer the question of whether or not this represents a viable grid-storage solution, since we haven't built it at remotely close to the scale required.

It's not "if it isn't already being done, it can't be done"

It's "if it isn't already being done, it is extremely reckless to assume that it can be done cheaply at a massive scale".

Screw it, let's just use fusion. Nobody has actually built a fusion plant? Well, who cares if it hasn't already been done, that's a "foolish argument" in your own words. /s

It's even worse if there is not other dispatchable generation available unless people are willing to accept periodic blackouts.

We're in the process of building out a combined solar and battery installations in Guam, which is about the ideal case with predictable weather, predictable load, little heavy industry and low potential for load growth. It'll enable them to retire all their old fuel oil generators, but they'll be keeping the diesel/LNG plant for at least the next 30 years even if they only run it a few days worth of time every month.

Hydrogen could also be stored in depleted gas fields and in deep saline aquifers. The storage capacity available is more than adequate.

Large projects are just expensive now. Nuclear would be competitive with either of these hydro projects.

You're conflating "expensive" with "unreliable". Even with infinite batteries, buying stored energy will always be more expensive than direct solar/wind.

"The solar heavy network wouldn’t need energy storage with an HVDC network."

So no, we wouldn't need that. HVDC would be far cheaper.

All of the Americas experience night time simultaneously for at least 8 hours a day. Even if we ran HVDC lines to the Sahara, there's still a period of time where most sunlight is shining on the pacific ocean.

We haven't done this to provide 100 MWh of storage. How on earth can we be confident it'll be easy to provide 1 TWh of storage, or 10 TWh?

People mostly talk about lithium ion storage because that's what's actually available, besides geographically limited options like hydroelectricity. Until there's a company that's building dozens of gigawatt hours of hydrogen storage it's a moot point. It's a technology that exists the laboratory, not one that's commercially available.

Superconducting would be nice to have, but doesn't seem necessary.

They aren't "off the shelf" technology yet.

It's a euphemism for storage heaters, storage air-conditioning, aluminium smelters that dial usage up and down and smart car chargers.

Lithium ion batteries are useful too, of course, but they cost more.

This is a problem where market based solutions shine. The only reason that fact isn't getting rammed down our throats by lobbyists is that the people who got religion about markets tended to be oil/gas people, who have since been thrashing the "renewables are unreliable" drum.

>Overproduction helps but doesn't eliminate intermittency.

Why should the goal be to eliminate it when we can adapt to it and thrive?

Personally, I'm more excited for applications of periodic free/-ve priced electricity than I am worried about shortages.

Overproduction is still not that common. These days wind and solar mostly just provide power that would have otherwise been produced by natural gas even when operating at peak capacity.

It is getting off the ground though. The UK has an energy tarriff popular with electric car owners for this reason. They can occasionally get paid to charge their cars. This type of thing will only become more common.

>And some things really can't be shaped.

Obviously not. Nonetheless pretending that all renewable intermittency has to be made up for with expensive lithium ion batteries is backwards thinking.

https://www.airliquide.com/sites/airliquide.com/files/2017/0...

This presentation says that the Spindletop hydrogen capacity is equivalent to ~120 GWh.

https://ukccsrc.ac.uk/wp-content/uploads/2020/05/John-Willia...

Backup generators would of course be expensive to build and maintain, but if they just sit idle 99% of the time maybe the cost would be acceptable. I assume a fossil fuel power plant that just sits idle could last a very long time.

Also, if you can run HVDC to the Sahara you could run it to hydro plants, so I don't think that's a good hypothetical.

But mostly, talking about pure solar just makes no sense.