Vocal Voices

The world's largest cold (cryogenic) energy storage plant is about to come online as a test bed. The idea is for it to store the energy from wind and solar for use later to even out the peaks and troughs.

It is actually not much more than a modified gas plant and they have been around for almost one hundred years. The big difference is that instead of taking off liquid oxygen (LOX -186 ºC) and liquid nitrogen (LIN -196 ºC) it stops at -194 ºC and they remain. The pressurised liquid is then stored in giant flasks for later use.

When the liquid is let back to the open air it expands very rapidly by an order of 700:1 and this pressure can be used to drive a turbine.

The test is only on the 5MW, scale but even that will provide power to 5,000 places for about three hours. The hope is to scale up to 200MW.

One to keep an eye on.

That sounds like a brilliant idea, hope it's viable commercially.

I can't think why it should not work. The RAF and many large airports had their own gas plants as they use lots of LIN and LOX, so it is tried and trusted technology using little manpower. If it can be automated, as the test is about to discover, it could be a big part of the solution. Scaling up is no problem.

I guess if they can insulate it enough to not bleed too much energy, then why not. I had this discussion with an energy specialist back in 2000. He told me that the challenge with on/off energy was not capturing it, it was storing it so it could be used later. At that time, industrially, they had not progressed much beyond lifting heavy weights or using the type of friction motors the Swiss use in busses.

Apparently the site will use methane from the landfill as backup power, so if the flasks do have to vent off due to thermal induced pressure they can be topped up at any time.

The test site is about one eighth the size of a football pitch. If it works then scaling up to 200MW should be a minor problem. Each large city could have its own, as was the case with coal fired power stations of the past.

Which makes a lot of sense.