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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

#231

Post by flavius29663 »

yazaddaruvala wrote: post #197
flavius29663 wrote: post #150

Earlier quoted context omitted.

it's one thing to interconnect a few GW here and there, but to power the Texas grid you need 80GW or so. That is a humongous amount of power. You would need at least 10-20 HVDC projects that span thousands of miles each. BTW, Texas is already connected to the other grids, but not synchronized, e.g. https://www.tdworld.com/overhead-transmission/article/209645... As we all know, these kind of connections were not enoug…

Yeah I think we are on the same page. It’s likely just a difference between thinking 10-30 years out, and thinking 100-300 years out.

I don't see how more years make it more likely to have more interconnection. The power requirements will balloon, it might be still cheaper to have some local generators instead of investing in long range transmission

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

#232

Post by ed25519FUUU »

yazaddaruvala wrote: post #39
cbmuser wrote: post #19

It doesn't matter that solar itself is cheap, it still needs backup plants which are the reason Germany has the highest electricity prices - world-wide. > https://www.globalpetrolprices.com/electricity_prices/ It's really strange that users on HN keep rehashing the myth that solar and wind energy will result in lower electricity prices for consumers - they won't, never. Even if solar and wind energy was free, consume…

Here is a commercial installation of solar + storage at $0.04/kWh[1]. And it’s not unique, that article links to the cheapest solar + storage in the US at $0.025/kWh. Additionally, these are today’s prices, as per this article the price for renewables is dropping exponentially every year. And if Elon Musk is to be believed (which I do) the price for storage is also dropping exponentially. [1] https://pv-magazine-usa.…

Right now the grids in Texas go negative from an over abundance of wind power, and California regularly pays to get rid of peak power during the duck curve. It’s cheap, and also not very valuable.

The stable, high-duty cycle of a power plant is very valuable per kWh, and what renewables must compete against. Maybe someday we’ll get cheap versions of that through new battery inventions, but that day is definitely not today or the near future. There’s only one carbon free way to get it at scale.

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

#233

Post by philipkglass »

mlyle wrote: post #173
pfdietz wrote: post #166

Earlier quoted context omitted.

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.

Electrolytic hydrogen plants of up to 250 MW were constructed in the 20th century by the use of smaller electrolysis units in parallel. All of them were for producing ammonia from hydrogen. See table 3-2 on page 99 of this NASA report from 1975:

"Survey of Hydrogen Production and Utilization Methods"

https://ntrs.nasa.gov/api/citations/19760008503/downloads/19...

250 MW, Rjakon, Norway, built 1965

170 MW, Kima, Egypt, built 1960

125 MW, Nangal, India, built 1958

90 MW, Trail, Canada, built 1939

25 MW, Curco, Peru, built 1958

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

#234

Post by philipkglass »

Manfredo_1 wrote: post #100
pfdietz wrote: post #81

Earlier quoted context omitted.

One would not use batteries for the "rare, but prolonged" storage use case. You'd want something with lower capital cost, even if it were much less efficient. For example: hydrogen burned in turbines.

Hydrogen storage remains in the prototyping phase. We have no significant amount of hydrogen grid storage. Like thermal batteries or synthetic methane, hydrogen represents a potential storage solution but not one that we know will scale and be effectively deployed at the scope required. If we actually deploy 50 GWh of hydrogen storage, and demonstrate that it can cheaply and reliability be built at scale then your po…

Hydrogen is stored underground in Texas salt formations at Clemens Dome, Moss Bluff, and Spindletop. The largest of them, Spindletop, was completed in 2017:

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...

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

#235

Post by cmcnab »

Qwertious wrote: post #96
manfredo wrote: post #53

Earlier quoted context omitted.

Even achieving just one hour of storage globally amounts to 2.5 TWh of storage. By comparison the entire world produces ~300 GWh worth of lithium ion battery annually. That leaves geographically limited options like pumped hydroelectricity, and solutions not yet deployed at any significant scale like hydrogen fuel cells, synthetic methane, thermal batteries, flywheels, etc. Realistically we should saturate daytime en…

>By comparison the entire world produces ~300 GWh worth of lithium ion battery annually. 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…

I had a house for a time that had just what you describe: a concrete block thermal mass set in the foundation. There were ducts running through it as part of the forced-air system. During the days, especially sunny days, the block soaked up the excess heat and then radiated it back out during the night. It worked quite well; indoor temperatures stayed remarkably consistent. A company called Adirondack Alternate Energy were the architects. https://aaepassivesolar.com/low-energy.html

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

#236

Post by hn_throwaway_99 »

turtlebits wrote: post #48
hn_throwaway_99 wrote: post #33

Earlier quoted context omitted.

Most people will have a big battery in their garage capable of powering their house for days pretty soon.

Unless battery prices drastically drop, 2 days of power is 60kwh (quoting earlier figure), even if batteries were $100/kwh, that's $6000 in batteries (or ~$9 if you're on grid) edit: bad math, had $60k

I should have been more explicit in my post. I was talking about car batteries. Tesla cars have batteries in the 60-100 kWh range, and Vehicle-To-Home (V2H) power is becoming a real thing, and I predict over the next few years it could have a large impact on the ability of the grid to use that energy storage to help even out renewable power variability.

See https://electrek.co/2020/05/19/tesla-bidirectional-charging-...

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

#237

Post by elihu »

mtalhaashraf wrote: post #220
elihu wrote: post #217

Earlier quoted context omitted.

Huh, that's actually not bad. That makes the idea of connecting Asia/Africa/Europe with the Americas for 24-hour solar power seem doable. I assume it would be tremendously expensive to build, but also have substantial benefits long into the future.

The level of dependency on others and the associated risks would likely discourage this

That's true to a degree; if someone were able to cripple half the world's economies just by disabling a cable then yes, that's a serious issue. On the other hand, if all the involved countries maintained backup power (i.e. gas or coal generation) that could be turned on in an emergency but otherwise unused, then the risks could be mitigated.

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.

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

#238

Post by mlyle »

philipkglass wrote: post #233
mlyle wrote: post #173

Earlier quoted context omitted.

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

Electrolytic hydrogen plants of up to 250 MW were constructed in the 20th century by the use of smaller electrolysis units in parallel. All of them were for producing ammonia from hydrogen. See table 3-2 on page 99 of this NASA report from 1975: "Survey of Hydrogen Production and Utilization Methods" https://ntrs.nasa.gov/api/citations/19760008503/downloads/19... 250 MW, Rjakon, Norway, built 1965 170 MW, Kima, Egypt…

??? Those are input powers of terrifically inefficient and expensive electrolyzers. That 250MW plant put out 17MW of hydrogen -- (120 (megajoules / kilogram)) * ((0.000236 kilograms) / (cubic foot)) * (2 200 000 ((cubic feet) / hour)) = 17,306,667 Watts.

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

#239

Post by philipkglass »

mlyle wrote: post #238
philipkglass wrote: post #233

Earlier quoted context omitted.

Electrolytic hydrogen plants of up to 250 MW were constructed in the 20th century by the use of smaller electrolysis units in parallel. All of them were for producing ammonia from hydrogen. See table 3-2 on page 99 of this NASA report from 1975: "Survey of Hydrogen Production and Utilization Methods" https://ntrs.nasa.gov/api/citations/19760008503/downloads/19... 250 MW, Rjakon, Norway, built 1965 170 MW, Kima, Egypt…

??? Those are input powers of terrifically inefficient and expensive electrolyzers. That 250MW plant put out 17MW of hydrogen -- (120 (megajoules / kilogram)) * ((0.000236 kilograms) / (cubic foot)) * (2 200 000 ((cubic feet) / hour)) = 17,306,667 Watts.

I think that you slipped a decimal point. The mass of a cubic foot of hydrogen is about 0.00236 kg, not 0.000236 [1]. That means that the output power is an order of magnitude greater than you calculated -- 173 megawatts.

[1] https://microsites.airproducts.com/gasfacts/hydrogen.html

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

#240

Post by imtringued »

dukeofdoom wrote: post #93
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…

So I've been watching these Van build outs into full time living vans for travel. Most of them have solor panels on the roof, and 3 two hundred watt batteries. One guy said it would take him 23 days to fully charge these batteries off of solar vs just a few hours to charged them from the alternator when he is driving. It just doesn't seem very practical at this point. They all seem to have 2 or 3 thousand watt panels…

I saw an EV van that had solar panels that generated enough power to drive 50km per day. It was fully decked out to a comical level though.
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