A new study models what kind of performance will be necessary for long-duration energy storage (LDES) to make a real difference to a clean grid. The results are daunting. (If you don't want to read, you can listen!)
Not to embarrass you with gushing, but this is what I love about your writing... wonderful summary, accessible to the interested layperson. I wouldn't have time to pour over Jesse Jenkin et al.'s work, but it's so helpful for the advocacy & consulting work I do to have this kind of synopsis. Anyways, I'll stop - Just wanted to say thanks. Kudos to all the brilliant academics who do the original research too, of course!
David, what do you think of research from Stanford's Mark Jacobson or from Tony Seba (https://tonyseba.com/wp-content/uploads/2020/11/RethinkingEnergy2020-2030-LRR.pdf) that say that we don't need long term storage to cheaply decarbonize the grid? I recall that you also wrote about a CO study that showed deep decarbonization with existing technology could meet Colorado's energy needs and also save a lot of money. Is long term storage really necessary?
Quite the eye-opener! Thanks :) We have a lot of work ahead...
Last week, you wrote about the value of distributed power and storage, including EVs at stabilizing demand on the grid. How do you think that piece interacts with this article? Does it reduce the need for LDES at all?
David, have you confused kW power capacity with kWh of energy storage when you said that PHES costs hundreds of dollars per kWh?
The "Snowy 2" PHES project in Australia has a white-elephant-grade 400% cost overrun, from $2B to $10B, and even it has a mere $5/Watt of power capacity, and $28/kWh of energy storage capacity.
Yes, lots of prairie states have no topography, but anywhere near any mountains and tall hills, I can see it beating out Form Energy.
In 2013 I was a consultant tasked with writing a report on how we transition to 100% renewable electric grids and the problem of long duration storage quickly revealed itself to be the most challenging. I came to realize that the ability to create hydrogen and other fuels from renewable electricity (and water) was the solution. Hydrogen or other fuels can be stored in conventional and even existing storage infrastructure and pulled out and burned in conventional and even existing power plants. The ACES project in Utah will store a thousand times as much hydrogen energy in underground salt caverns as all the batteries currently in service in the US, at a marginal storage cost of $1-2/kWh, 1% of battery costs. Although sometimes cast as a "new" technology, creating hydrogen (and ammonia) from electricity as been done at scale for nearly a century.
Excellent piece. I learned a lot about LDES options reading this!
"The problem with chemical storage is that, while energy capacity costs are low, there’s lots of infrastructure and conversion processes involved in making hydrogen, storing it, capturing CO2, combining hydrogen and CO2, and then burning the resulting fuel in combustion turbines"
You can burn nearly pure hydrogen in a modified gas turbine, without these CO2 steps (though you certainly need them if you want to convert it to liquid fuels or ammonia, or various other things we may want it for). See GE, for example: https://www.ge.com/gas-power/future-of-energy/hydrogen-fueled-gas-turbines.
Secretary Grantholm announced the DOE's first Energy Earthshots Initiative last week - their target is an 80% reduction in the cost of clean hydrogen, to $1.00/kg in ten years....
How to think about what grid-scale looks like as a percentage of overall energy use if we really push distributed generation and (short-term) storage? That is, what percentage of our overall energy use is going to come out of LDES? I think that if you mention this, I missed it. Of course, as we electrify more stuff, we need more.
I continue to think about shifting urban development patterns, and other strategies to reduce overall demand (or at least demand growth). Have you addressed these ideas already? Might you care to? Thanks again for all your hard work!
Great summary. Thanks. In the near/mid term, in most places, we seem to be a long way from truly needing LDES, though its a really cool set of technologies for an energy nerd to ponder. I mean, really, PV performance is so boring.
I'm OK with even "dirty" "firm" BACKUP generation in the medium term. (A lot of folks conflate "firm" with "baseload." Need to be clear.) This year in CO, Platte River Power Authority released an IRP showing 90% wind and solar and some short duration storage, and 10% NG backup by 2030. To me that's insanely great for nine years out, but oh how the activists crowed, OMG, OMG, PEAKER PLANTS! Fossil fuels! NO, NO, NO! To me a bigger near term problem is, IF renewable fractions can be increased fast enough, what's to be done with all the inflexible baseload power?
Now CO is a great renewable location, so that 10% backup fraction will be higher in many places. But Xcel here is running around now saying we need storage, baseload, etc. etc., to get above 40% or 60% renewables, or something, depending on the day and audience.
In any case, truly needing LDES will be a great problem to have. Now I need to read and ponder that whole paper.
Why is it that most of the conversations on grid firming don't consider the other half of the equation - the demand side? Buildings are most of the demand side. Better insulation, mass, solar control, equipment efficiency, energy recovery, and active thermal storage are all options to reduce or eliminate grid demand at times anti-correlated with VRE. Is it simply because load studies don't disaggregate demand as they do generation, and so there is a strong streetlight effect bias here towards the generation side when considering proposed solutions?
Some differences to be sure, but I was amused by the commonalities between the Energy Vault video simulation of lifting blocks by crane and the 2-century-old long-case "grandfather" clock in my living room, with suspended lead weights. (It can run on organic lamb chops, but it's not particular, and does equally well on tofu or potatoes.)