Jenny ChaseRE: https://mastodon.green/@solar_chase/115405274671180986
Small victories: BNEF has changed its definition of long-duration storage to this! Thank you BNEF's LDES queen Yiyi Zhou.
Sometimes you can be annoying enough to be the change you want to see in the world. In a small, pedantic but nonetheless clarifying way.
(What do you mean organisations that aren't BNEF have not yet adopted this definition? Also I should care about those why?)
Owen Mehegan@solar_chase as a layperson I have read this several times and I'm still not sure what it means. I know I'm not really the audience, but can you give an example of what is and isn't LDES when using this metric?
Mathis@literatesavant @solar_chase Pumped-storage hydroelectric power is a good example. The energy capacity is only proportional to the size—and thus the cost—of the reservoir. It is quite independent of the cost of the pump/generator and other electrical equipment. Hence its power capacity (generators) is decoupled from the energy capacity (reservoir).
soaproot@mathis @literatesavant @solar_chase Oh, maybe I'm starting to get it. We're looking for the right word/concept to describe being able to handle seasonal variations in load. And the decoupling thing is supposed to get at whether you can cheaply make the storage (in this example the reservoir) big. Like not just add a few battery packs big, more like a factor of a thousand from that.
@literatesavant where you have a tank or reservoir of some kind of storage medium (water for pumped hydro, molten salt for some types of thermal storage, compressed air for CAES, stuff held high up for gravity storage, flow batteries, metal air batteries because they have a reaction medium).
Ie, you can add more of the storage medium without scaling up the whole thing. You can sort of do this with lithium ion, but not as well as for most of these options.
@literatesavant I should add, the storage medium has to be relatively cheap. Lithium ion cells, for example, don't really count as they are already a massive part of system capex.
glasspshrAs someone who’s worked on flow batteries and metal air batteries, I don’t get why metal air batteries are classed in here. Are you saying the reduced metal is being stockpiled as things get charged? Not static?