Why isn't electricity cheaper?



Siemens Gamesa builds offshore wind farms, but is experimenting with grid-scale storage. Their thermal electric storage is based around electrically heating rocks to 750 C, then regenerating electricity on demand through a steam cycle. The latter inevitably means it is complex, has a certain minimum size, needs water, and so on.

Their prototype launched last month with a thousand tonnes of rocks is the same capacity as Tesla’s grid battery in New South Wales – about 130 MWh. But they say it will scale to gigawatt-hours and will store energy for a week. Round-trip efficiency is about 40%, which sounds inefficient until you think about all the curtailed renewable energy where we dump 100%.

I couldn’t find any information on cost, but Tesla’s NSW battery cost over $90m which gives plenty of leeway to be cost competitive. The three-prong plan is to 1) use waste heat from existing thermal plant, so not all your energy involves 60% electricity loss, 2) keep the steam plant part of decommissioned fossil fuel generators to hook up to the new thermal storage, 3) build lots of new units and evolve to grid-scale storage.

Video, website, and articles below.





so, it’s a glorified storage heater!?

all joking aside I wonder if the new smart meter regime will lead to more interest in night time immersions and updated storage heaters. If there’s a shed load off wind turbines operating then it makes sense to use less efficient but cheap technology instead of fancy dan heat pumps


Probably not, EV’s and home battery systems will soak up that spare capacity rendering any night saver tariff obsolete.


Definitely not. (I do realise you’re joking). At 750 C it would be starting to glow – it’s about the temperature of the coolest lavas. The point of that is that the energy is more useful at that temperature, due to the lower entropy of high temp generation. However it sounds complicated and I can’t find anything on projected costs which is the only thing that matters in energy applications unless you’re a doomster cult greenie. So could be a total white elephant.


That will be an interesting development. Who are the leaders in fusion. I assume USA and china


My top two to watch in the fusion race at the moment are UK- and US-based. Though that’s out of a field of nearly twenty, and there are so many different avenues being pursued I wouldn’t be surprised to see something come out of left field either.

But for the next couple of years I’d be looking at two well-funded projects with serious research credentials launching into testing high-temperature superconductors (HTS) in compact tokamaks. They are UK-based Tokamak Energy and MIT Sparc.