LADWP Says It Will Shift Its Largest Gas Power Plant To Hydrogen (latimes.com)
- Reference: 0179956250
- News link: https://hardware.slashdot.org/story/25/11/03/2351252/ladwp-says-it-will-shift-its-largest-gas-power-plant-to-hydrogen
- Source link: https://www.latimes.com/environment/story/2025-10-29/ladwp-approves-controversial-hydrogen-conversion-plan-at-the-citys-largest-gas-plant
> The board of the Los Angeles Department of Water and Power on Tuesday approved a controversial plan to [2]convert part of the city's largest natural gas-fired power plant into one that also can burn hydrogen . In a 3-0 vote, the DWP board signed off on the final environmental impact report for an $800-million modernization of Units 1 and 2 of the Scattergood Generating Station in Playa del Rey. The power plant dates to the late 1950s and both units are legally required to be shut down by the end of 2029. In their place, the DWP will install new combined-cycle turbines that are expected to operate on a mixture of natural gas and at least 30% hydrogen with the ultimate goal of running entirely on hydrogen as more supply becomes available.
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> The hydrogen burned at Scattergood is supposed to be green, meaning it is produced by splitting water molecules through a process called electrolysis. Hydrogen does not emit planet-warming carbon dioxide when it is burned, unlike natural gas. [...] Although burning hydrogen does not produce CO2, the high-temperature combustion process can emit nitrogen oxides, or NOx, a key component of smog. [...] [T]he approved plan contains no specifics about where the hydrogen will come from or how it will get to the site. "The green hydrogen that would supply the proposed project has not yet been identified," the environmental report says. Industry experts and officials said the project will help drive the necessary hydrogen production.
"Burning hydrogen produced by 'excess' solar or wind power is a means of energy storage," adds Slashdot reader Bruce66423. "The hard question is whether it's the best solution to the storage problem given that other solutions appear to be emerging that would require less infrastructure investment (think pipes to move the hydrogen to the plant and tanks to store it for later use)."
[1] https://slashdot.org/~Bruce66423
[2] https://www.latimes.com/environment/story/2025-10-29/ladwp-approves-controversial-hydrogen-conversion-plan-at-the-citys-largest-gas-plant
So, the plan is ... (Score:4, Informative)
Solar -> Electricity -> Electrolysis -> Hydrogen -> Combustion Turbine -> Electricity
Why not:
Solar -> Electricity -> Battery -> Electricity
It would appear that the latter would have a better end to end efficiency. Bypassing the losses in electrolysis and combustion.
Re: (Score:2)
My first thought was to build a gravity energy storage system, near a damn, or a deep cave. But... Batteries are most likely the best option. Through all of the complications of making hydrogen, and transporting it, the efficiency must go down below 20%, while batteries or gravity would be around 90%.
Re: So, the plan is ... (Score:1)
Batteries are expensive and don't scale on demand very well. Steel tanks can be produced much more quickly and cheaply.
Electrons are easy to move; molecules are easy to stockpile.
This is a tradeoff. Tradeoffs exist in real life. The reality distortion field has little effect on them.
Re: (Score:2)
> Batteries are expensive and don't scale on demand very well. Steel tanks can be produced much more quickly and cheaply.
I'm going to disagree. Remember, we're talking about H2, the smallest molecule, which has a lot of trouble being contained and also tends to make metals weak and brittle (or hydrogen embrittlement). An H2 tank failure is not a good thing. :)
OTOH, batteries aren't all that hard to make and they can build a new Tesla Megapack in an hour or so. (Of course, there is a wait list, but getting the right number of packs is an exercise in up-front planning.) Last I heard, a Megapack3 is about $1.4M to hold ~5MWh. I
Hopefully the plan is not to greenwash ... (Score:2)
> Solar -> Electricity -> Electrolysis -> Hydrogen -> Combustion Turbine -> Electricity
> Why not:
> Solar -> Electricity -> Battery -> Electricity
> It would appear that the latter would have a better end to end efficiency. Bypassing the losses in electrolysis and combustion.
Which batteries? The ones manufactured in the US/EU with proper pollution controls? Or the ones manufactured in Mongolia that are turning the place into a toxic wasteland? But hey, cheap batteries, greenwashed virtue signaling vibes, and Mongolia is far away.
Combustion is not the only option ... (Score:2)
> Solar -> Electricity -> Electrolysis -> Hydrogen -> Combustion Turbine -> Electricity
> Why not:
> Solar -> Electricity -> Battery -> Electricity
> It would appear that the latter would have a better end to end efficiency. Bypassing the losses in electrolysis and combustion.
See Fuel Cell post below yours. Combustion is not the only option.
[1]https://hardware.slashdot.org/... [slashdot.org]
[1] https://hardware.slashdot.org/comments.pl?sid=23836944&cid=65771512
Re: (Score:2)
> Solar -> Electricity -> Electrolysis -> Hydrogen -> Combustion Turbine -> Electricity
> Why not:
> Solar -> Electricity -> Battery -> Electricity
> It would appear that the latter would have a better end to end efficiency. Bypassing the losses in electrolysis and combustion.
Depends on how much energy you want to store and how long you want to store it.
The size of a battery is directly proportional to how much energy you store. If the battery provides a megawatt for ten hours, the battery weighs ten times as much as a battery providing a megawatt for one hour. On the other hand, for a fuel cell, only the storage tank is proportional to how much energy you store (and the storage tank is by far the cheapest part of the fuel cell system). The longer the storage period, the more a
Re: (Score:2)
Here's some efficiency numbers...
If you start with & stay with electricity, after transportation/distribution, you end up with ~94% of your original energy starting amount at the site for usage.
If you start with electricity then change to H2, after electrolysis + transportation/distribution, you end up with ~68% of your original starting energy at the site for usage.
Hmm, which is more, 94% or 68%? :) It is never better to go from electricity to H2 for energy unless you have an absurdly special use case
Once they make the effort to get H2 by itself (Score:2)
Maybe they'll be motivated to understand that you get much better efficiency from it with fuel cells than with thermal expansion. South Korea apparently understands this: [1]The Shinincheon Bitdream Hydrogen Fuel Cell Power Plant in Incheon can produce 78.96 MegaWatts of power [wikipedia.org]. [2]The hydrogen fuel cell power plant in Gyeongju will produce 107.9MW of power for $550M to build [fuelcellsworks.com]. Scattergood produces 800MW from three turbines. Google tells me that it takes 44 to 53 tonnes of hydrogen per hour to produce 250 MW fr
[1] https://en.wikipedia.org/wiki/Hydrogen_fuel_cell_power_plant#Shinincheon_Bitdream_Hydrogen_Fuel_Cell_Power_Plant
[2] https://fuelcellsworks.com/2024/11/28/fuel-cells/south-korea-to-construct-world-s-largest-hydrogen-fuel-cell-power-plant-in-gyeongju
Re: (Score:3)
> Maybe they'll be motivated to understand that you get much better efficiency from it with fuel cells than with thermal expansion.
Yes... and no.
First, combined-cycle natural gas generators are well down the learning curve. There is no problem producing megawatts, even gigawatts, with natural gas, and converting this to hydrogen is straightforward. Fuel cells, on the other hand, have never been scaled up.
Second, fuel cells are expensive, use rare materials like platinum for catalysts. Third, it's not clear that they can last for thousands of cycles.
So, trading some efficiency for a technology that's know, reliable, and cheap? Might
If you make hydrogen you can make methane (Score:1)
And the beautiful thing about methane is it requires absolutely no changes to the gas plant since natural gas is almost entirely methane. There is also existing storage, pipeline, and processing infrastructure that handles natural gas.
Re: (Score:3)
Leaked methane is a greenhouse gas with eighty times the power of carbon dioxide.
Re: (Score:2)
More like [1]28 times [epa.gov] and it breaks down in about 10 years as opposed to 30.
[1] https://www.epa.gov/gmi/importance-methane
Coal gas (Score:2)
50% of [1]coal gas [wikipedia.org] is (or was) Hydrogen. Conversion from Town Gas to Natural Gas meant converting to mostly methane.
[1] https://en.wikipedia.org/wiki/Coal_gas
A plant that burns nonexistent hydrogen. (Score:4)
> The approved plan contains no specifics about where the hydrogen will come from or how it will get to the site. "The green hydrogen that would supply the proposed project has not yet been identified"
Enough said.
Re: (Score:2)
Its chicken and egg. There won't be suppliers if there are no buyers.
Re: (Score:2)
> Its chicken and egg. There won't be suppliers if there are no buyers.
It is not clear there will be suppliers even if there are buyers. Storing energy by making hydrogen is grossly inefficient. Even pumped hydro is much more efficient. It only seems to make sense if generation greatly exceeds transmission capacity for such a long time that no practical energy storage mechanism can buffer it. There are cases where wind farms are required to shut down but those are due to local weakness of the power grid and I don't think these wind farms have storage anyway.
Re: (Score:2)
What they lose per widget, they'll make up for in volume.
Re: (Score:2)
Yep. Guess where hydrogen comes from these days: natural gas.
Hydrogen from surplus solar/wind, energy storage (Score:2)
>> The approved plan contains no specifics about where the hydrogen will come from or how it will get to the site. "The green hydrogen that would supply the proposed project has not yet been identified"
> Enough said.
Actually there is quite a bit to say ...
The summary mentions the hydrogen will displace some natural gas used for electrical power generation: "convert part of the city's largest natural gas-fired power plant into one that also can burn hydrogen"
While the plan does not specifically identify a source, another poster points out that hydrogen production can be an "energy storage" method for any surplus solar or wind power on a given day.
Also the thing they signed off on is the final environmental impa
Re: (Score:2)
> ...While the plan does not specifically identify a source,
Stop right there. It wasn't the article that "did not specifically identify a source". The article said that the Los Angeles Department of Water and Power didn't identify a source.
> another poster points out that hydrogen production can be an "energy storage" method for any surplus solar or wind power on a given day.
If you follow the technology, right now production of hydrogen by electrolysis is slow, inefficient, and relies on expensive catalysts.
Maybe someday it won't, but right now, hydrogen is made... from natural gas.
Re: (Score:2)
> While the plan does not specifically identify a source, another poster points out that hydrogen production can be an "energy storage" method for any surplus solar or wind power on a given day.
Right. And that's the interesting question, what's the best way to store surplus solar/wind electricity? Batteries? Hydrogen (to be burned or to run a fuel cell)? Sold to other grids who need it and bought back when they have a surplus? As hot sand?
I wouldn't jump to the assumption that generating, storing, and burning hydrogen is obviously best. It does have the nice benefit that one might generate it on-site (you've got the high capacity tie to the grid just sitting there, right?) and you're using a very