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

cleantechnica.com

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

#171

Post by Manfredo_1 »

Qwertious wrote: post #167
Manfredo_1 wrote: post #157

Earlier quoted context omitted.

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...

From your own source: "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.

A solar heavy network would still need 12 hours of storage to accommodate nighttime energy use. More actually, because of greater seasonal fluctuations further from the equator.

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.

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

#173

Post by mlyle »

pfdietz wrote: post #166
mlyle wrote: post #162

Earlier quoted context omitted.

When the largest electrolyzer we have in the world is 10MW... and hydrogen storage hasn't been demonstrated at anywhere near the scale you're talking about... it's a tad of a stretch to talk about it being "off the shelf." Particularly when you point to nuclear fuel reprocessing and breeding as nonexistent in the same thread.

We can run electrolysers in parallel to scale to any desired output level. There might be economies of scale to make them even larger, or there could be economies of manufacturing scale of making smaller ones at higher volume. PV and wind are examples of technologies that work well with large numbers of not so large units, replicated as needed. This is a nice place for a technology to be.

A few prototype / demonstration units at 10MW scale and lower is not proven, off the shelf technology. Fullstop.

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

#174

Post by Manfredo_1 »

Hypx wrote: post #169
Manfredo_1 wrote: post #160

Earlier quoted context omitted.

> 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…

> 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. Seriously, your projection is out of control here. A gas turbine burning hydrogen does not experience any stresses that is meaningfully different from one burning natural gas or kerosene. Simply applied engineering can solve…

> A gas turbine burning hydrogen does not experience any stresses that is meaningfully different from one burning natural gas or kerosene. Simply applied engineering can solve all of the issues associated with hydrogen gas turbines.

Did you misread that comment? The point was that hydrogen's application in the chemical industry don't involve turbine blades spinning at extreme speeds at high temperatures.

Yes, the principle of combusting a gas, driving a turbine with the expanding gas, and using that turbine to drive a compressor is the same. That doesn't mean you can just feed a gasoline powered turbine hydrogen and be done with it. The turbines that can run hydrogen today can only run a small portion of it.

https://www.economist.com/science-and-technology/2020/12/08/...

> The challenges of using hydrogen go beyond body shape, though. Redesigning a turbine engine to run on the stuff will be a multi-billion-dollar endeavour. Hydrogen burns faster than kerosene, and also burns hotter. That means materials exposed to its combustion experience greater stresses. It also risks increasing the pollution generated in the form of oxides of nitrogen, which would partially negate the environmental benefits of burning hydrogen. And it would be useful as well to arrange matters so that some of the energy used to compress or liquefy the hydrogen for storage could be recovered and put to work.

The Soviets built a plane that flew on hydrogen, but it only completed 100 flights. And only part of those were with hydrogen, the rest were with natural gas: https://en.wikipedia.org/wiki/Tupolev_Tu-155

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

#175

Post by Hypx »

Manfredo_1 wrote: post #168
Hypx wrote: post #159

Earlier quoted context omitted.

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.

That link you provided doesn't encompass gas turbines. Gas turbines capable of burning hydrogen do exist, but only at smaller concentrations, 70% methane and 30% hydrogen or less.

In addition to what I said in the other post regarding gas turbines, you also don't need a gas turbine to generate power. As long as you can boil water the rest follows logically.

Honestly, you should learn some thermodynamics and chemistry before accusing others of being ignorant.

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

#176

Post by Manfredo_1 »

Hypx wrote: post #175
Manfredo_1 wrote: post #168

Earlier quoted context omitted.

That link you provided doesn't encompass gas turbines. Gas turbines capable of burning hydrogen do exist, but only at smaller concentrations, 70% methane and 30% hydrogen or less.

In addition to what I said in the other post regarding gas turbines, you also don't need a gas turbine to generate power. As long as you can boil water the rest follows logically. Honestly, you should learn some thermodynamics and chemistry before accusing others of being ignorant.

Right, but then we're not talking about combined-cycle gas turbines to convert hydrogen back into electricity. If we're going to boil water than that's much less efficient than the ~66% efficiency we get out of combined cycle gas turbines.

Also, in case you weren't aware a combined cycle turbine also involves boiling water and spinning a turbine. The reason why they're so efficient is because energy is extracted both from the gas turbine (basically a jet engine) and a steam turbine driven by the heat from the exhaust from the gas turbine.

>Honestly, you should learn some thermodynamics and chemistry before accusing others of being ignorant.

Hydrogen embrittlement is a real thing, don't just go hand-waving it away: https://www.energy.gov/sites/prod/files/2014/03/f12/hpwgw_em...

What about thermodynamics am I missing?

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

#177

Post by Hypx »

Manfredo_1 wrote: post #174
Hypx wrote: post #169

Earlier quoted context omitted.

> 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. Seriously, your projection is out of control here. A gas turbine burning hydrogen does not experience any stresses that is meaningfully different from one burning natural gas or kerosene. Simply applied engineering can solve…

> A gas turbine burning hydrogen does not experience any stresses that is meaningfully different from one burning natural gas or kerosene. Simply applied engineering can solve all of the issues associated with hydrogen gas turbines. Did you misread that comment? The point was that hydrogen's application in the chemical industry don't involve turbine blades spinning at extreme speeds at high temperatures. Yes, the pri…

> The Soviets built a plane that flew on hydrogen, but it only completed 100 flights. And only part of those were with hydrogen, the rest were with natural gas: https://en.wikipedia.org/wiki/Tupolev_Tu-155

So you admit this has been done since the 1980s? You seriously don't think we can improve on 33 year old technology?

How dishonest are you going to get before you will admit you were wrong?

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

#178

Post by rhodozelia »

pfdietz wrote: post #170
rhodozelia wrote: post #161

Earlier quoted context omitted.

In British Columbia they are building a 1000 MW hydro plant that is going to cost 10-12 billion. Similar story at muskrat falls in Labrador. Large projects are just expensive now. Nuclear would be competitive with either of these hydro projects.

That hydro project doesn't sound competitive.

I guess not, but when two or three projects come in at the 10 billion cad mark it’s a pretty good sign that’s our cost to build. Not necessarily unique to hydro - we might have high cost to build anything

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

#179

Post by Manfredo_1 »

pfdietz wrote: post #155
Manfredo_1 wrote: post #151

Earlier quoted context omitted.

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.

For the third time, storage is only one part of the puzzle. We also need a way to cheaply electrolyze water into hydrogen, compress it into the storage facility, and then use it to generate electricity. Nobody doubts that you can pump hydrogen into a big cave. What's dubious is transforming this into a usable energy-storage facility.

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.

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

#180

Post by Manfredo_1 »

Hypx wrote: post #177
Manfredo_1 wrote: post #174

Earlier quoted context omitted.

> A gas turbine burning hydrogen does not experience any stresses that is meaningfully different from one burning natural gas or kerosene. Simply applied engineering can solve all of the issues associated with hydrogen gas turbines. Did you misread that comment? The point was that hydrogen's application in the chemical industry don't involve turbine blades spinning at extreme speeds at high temperatures. Yes, the pri…

> The Soviets built a plane that flew on hydrogen, but it only completed 100 flights. And only part of those were with hydrogen, the rest were with natural gas: https://en.wikipedia.org/wiki/Tupolev_Tu-155 So you admit this has been done since the 1980s? You seriously don't think we can improve on 33 year old technology? How dishonest are you going to get before you will admit you were wrong?

It was done for a very short duration during the 1980s as a technology demonstrator. A prototype, not an actually commercially viable product. Yes, we can improve on a 33 year old technology, but it's not something we can just buy off the shelf. GE thinks it'll take until 2045 to make turbines that run off of 100% hydrogen.

> How dishonest are you going to get before you will admit you were wrong?

When you show me where I can buy a gas turbine that runs off of hydrogen. Not a gas turbine that runs mostly off of natural gas with a little bit of hydrogen mixed in. Not a press release of a company saying "we have experience with hydrogen turbines". If you're going to say that hydrogen gas turbines are off-the-shelf then show me the shelf off of which I can buy it.

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