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

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

#151

Post by Manfredo_1 »

pfdietz wrote: post #138
Manfredo_1 wrote: post #112

Earlier quoted context omitted.

And are we currently using any of these caverns for electrolysis and grid storage? All you said is that we have a big cavern that we could fill with hydrogen. I'm asking if anybody is actually building hydrogen grid storage at any significant scale. Are there any facilities that take in excess energy from renewables, turn it into hydrogen, and then turn that hydrogen back into electricity? We both know the answer: th…

Dude. You are falling back to the "if it isn't already being done, it can't be done" argument. Please stop this foolishness. 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 mea…

Storing hydrogen is only one piece of the puzzle. Yes, if you happen to live near an abandoned salt mine that's a convenient place to put a large quantity of hydrogen. That doesn't solve the problem of massive electrolysis facilities, and turbines that can burn hydrogen.

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

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

#152

Post by kragen »

rhodozelia wrote: post #144
kragen wrote: post #87

Earlier quoted context omitted.

This is more or less what post-combustion capture carbon-capture-and-storage plants do, with the minor detail that they do the actual combustion above ground instead of below ground. But the inputs and outputs are as you describe: oxygen from the air, fossil fuels from underground, CO₂ outputs injected back underground, heat outputs sent to somewhere unspecified, typically the air. CCS power stations are substantiall…

Economically uncompetitive compared to solar/wind 500% overbuilt? How many hours storage have to be added to the solar / wind to make a ccs gas plant competitive?

Probably, yeah. As I said in my other comment, the whole question of utility-scale storage cost modeling is difficult to get a good handle on.

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

#153

Post by pfdietz »

Manfredo_1 wrote: post #145

That "manipulation of hydrogen" mostly involves use in the the chemical industry. We don't use hydrogen to power gas turbines. I'm not sure why you're trying to deny the existence of chemical facts: https://www.twi-global.com/technical-knowledge/faqs/what-is-... .

> That "manipulation of hydrogen" mostly involves use in the the chemical industry. We don't use hydrogen to power gas turbines.

So, when you said hydrogen rapidly corrodes any metal it comes into contact with, that didn't include the metal that the chemical industry makes their equipment from? So, let's just put a "this is chemical industry" signs on our hydrogen storage plants, and presto! Magically protected!

Note that one of the things the chemical industry does with hydrogen-rich gases is burn them in combustion turbines, just like in a proposed hydrogen energy storage facility. Turbines for burning hydrogen have been available for decades. See, for example, what General Electric says:

https://www.ge.com/power/gas/fuel-capability/hydrogen-fueled...

"Our turbines have nearly 30 years of experience operating on a variety of fuels that contain hydrogen, totaling over 6 million operating hours as hydrogen-fueled turbines using concentrations ranging from 5% to 95% (by volume)."

Off. The. Shelf.

> I'm not sure why you're trying to deny the existence of chemical facts: https://www.twi-global.com/technical-knowledge/faqs/what-is-....

I'm not sure why you're presenting a link that doesn't back up the claim you made.

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

#154

Post by netflixandkill »

zizee wrote: post #41

I think the future will be robust national/international grids, with a mixture of storage options (batteries/pumped hydro) to smooth out the intermittent nature of wind and solar. 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, an…

It's not cynicism, it's understanding capacity factors and how difficult large scale storage is. If solar panels have a capacity factor of around .25, which is what we're seeing in real installations worldwide, then it is necessary to overproduce by at least 4x and store it somewhere for off-peak solar production hours.

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.

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

#155

Post by pfdietz »

Manfredo_1 wrote: post #151
pfdietz wrote: post #138

Earlier quoted context omitted.

Dude. You are falling back to the "if it isn't already being done, it can't be done" argument. Please stop this foolishness. 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 mea…

Storing hydrogen is only one piece of the puzzle. Yes, if you happen to live near an abandoned salt mine that's a convenient place to put a large quantity of hydrogen. That doesn't solve the problem of massive electrolysis facilities, and turbines that can burn hydrogen. 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…

These are not abandoned salt mines, they are deliberately created caverns in salt domes. The cost of creating them is included in the capital cost ($1/kWh capacity).

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

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

#156

Post by Manfredo_1 »

panarky wrote: post #125
Manfredo_1 wrote: post #117

Earlier quoted context omitted.

Yes, those incentives exist to try and shape demand. But in practice, people rarely take advantage of them. And some things really can't be shaped. The pumps that deliver your water cannot have their demand shaped, unless you're willing to go without running water for some hours of the day.

If we paid the true cost of peak power, it might be worth pumping water with off-peak power and storing it locally.

Then our transition to solar + wind needs to include the cost of installing a septic tank and water reservoir in every household. And a thermal battery for heating. And an electric battery for lighting. And all the other things we'll need to do to accommodate an unreliable energy grid.

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

#157

Post by Manfredo_1 »

jeffbee wrote: post #65
manfredo wrote: post #62

Earlier quoted context omitted.

And then we'd have to continue that production for two and a half decades to get to 1 day of storage. And we'd also have to drastically increase our battery recycling capacity to match (remember most lithium ion batteries last 1000-2000 cycles).

Nobody needs 1 full day of storage.

We'd actually need 3 weeks of storage to migrate to a fully renewable grid: https://pv-magazine-usa.com/2018/03/01/12-hours-energy-stora...

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

#158

Post by pfdietz »

Manfredo_1 wrote: post #149
pfdietz wrote: post #142

Earlier quoted context omitted.

I will repeat the reply I gave elsewhere to this argument: Dude. You are falling back to the "if it isn't already being done, it can't be done" argument. Please stop this foolishness. 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…

You're falling back to the "if it works on paper it'll be guaranteed to work at scale, and work cheaply" argument. Please stop this foolishness. It's not just a question of storage, you can just use a salt cavern for that. It's also a question of electrolyzing water into hydrogen efficiently. And converting it back into electricity efficently. And building all of these systems cheaply. And deploying all of these syst…

Why shouldn't it scale? It's not as if it uses any rare materials. The geological formations in which hydrogen can be stored are abundant. The cost estimation should be good, since the technology is just integrating existing components. That's the easiest and surest kind of technology to roll out.

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

#159

Post by Hypx »

Manfredo_1 wrote: post #145

That "manipulation of hydrogen" mostly involves use in the the chemical industry. We don't use hydrogen to power gas turbines. I'm not sure why you're trying to deny the existence of chemical facts: https://www.twi-global.com/technical-knowledge/faqs/what-is-... .

Are you familiar with fuel gases? https://en.wikipedia.org/wiki/History_of_manufactured_fuel_g...

Burning hydrogen gas (blended with other gases) for heat or power has been around for a long time.

> I'm not sure why you're trying to deny the existence of chemical facts

You're projecting here.

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

#160

Post by Manfredo_1 »

pfdietz wrote: post #153
Manfredo_1 wrote: post #145

That "manipulation of hydrogen" mostly involves use in the the chemical industry. We don't use hydrogen to power gas turbines. I'm not sure why you're trying to deny the existence of chemical facts: https://www.twi-global.com/technical-knowledge/faqs/what-is-... .

> That "manipulation of hydrogen" mostly involves use in the the chemical industry. We don't use hydrogen to power gas turbines. So, when you said hydrogen rapidly corrodes any metal it comes into contact with, that didn't include the metal that the chemical industry makes their equipment from? So, let's just put a "this is chemical industry" signs on our hydrogen storage plants, and presto! Magically protected! Note…

> So, when you said hydrogen rapidly corrodes any metal it comes into contact with, that didn't include the metal that the chemical industry makes their equipment from? So, let's just put a "this is chemical industry" signs on our hydrogen storage plants, and presto! Magically protected!

I'd say you're being deliberately ignorant here, but I'm really not so sure. A gas turbine spins rapidly, putting huge stresses on the blades. They also operate at extremely high temperatures.

And from your link:

> The use of hydrogen as a gas turbine fuel has been demonstrated commercially, but there are differences between natural gas and hydrogen that must be taken into account to properly and safely use hydrogen in a gas turbine. In addition to differences in the combustion properties of these fuels, the impact to all gas turbine systems as well as the overall balance of plant, must be considered. In a power plant with one or more hydrogen-fueled turbines, changes may be needed to the fuel accessories, bottoming cycle components, and plant safety systems. GE’s broad field experience enables our engineers to understand the impact of using hydrogen as a gas turbine fuel.

Hmm, maybe not so simple.

And when we look at what's actually being deployed, it's not 100% hydrogen it's a mixture that's mostly natural gas with only a small portion of hydrogen:

https://www.nsenergybusiness.com/features/gas-turbines-hydro...

> The new gas turbines will be commercially guaranteed capable of using a mix of 30% hydrogen and 70% natural gas fuel. Between 2025 and 2045, the hydrogen capability will be systematically increased to 100% renewable hydrogen.

These turbines still mostly burn natural gas. GE says it'll get there eventually, possibly over the course of 3 decades.

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