British Engineering, mate.

[Grimly Curmudgeon]

Put that in your pipe and smoke it.

[The Natural Philosopher]

hahahaha ROFLMAO.

" this process is only 25% efficient but it is massively improved by co-siting the cryo-generator next to an industrial plant or power station producing low-grade heat that is currently vented and being released into the atmosphere"

So like all renewables it depends on cheap fossil fuel to work.:-)

More green pie in the sky.

[Dave Liquorice]

[Dave Plowman (News)]

It's a method of storing energy created at a time when it isn't needed until it is in the short term. And the efficiency is said to possibly be able to approach that of a rechargeable battery. But I dunno how practical it is - pumping water up to the top of a hill and using that to run a hydro electric system has its problems too.

[Dave Liquorice]

Well yes. Would get rid of the stupid "we don't want your power but we'll still pay you your well above market price". Every wind farm has to have a liquid air plant (paid for by the wind co) to even out the supply/demand problem.

But look at it another way instead of having to throttle your fossil plants up and down with demand which isn't very effcient you can run them with a steady throttle and dump to (or take) from the liquid air energy bank to meet demand fluctuations and you have the waste heat from the power station to help.

I'm also wondering what the energy density of liquid air is. Could it become a replacement for diesel/petrol in smaller vehicles? We seem to be able to handle LPG safely enough and that is flamable, liquid air is well air... I can see problems in winter though with frozen "radiators" (aka heat absorbers) to provide the energy for the phase change.

[Dave Plowman (News)]

Since it's only storing energy rather than producing it by burning, my gut feeling is it won't store anything like as much by volume as LPG.

[John Rumm]

If you take it as a 80:20 mix of Nitrogen / Oxygen, you get a specific latent heat of vaporisation of just over 200 kJ/kg compared to 46.8 MJ/kg if you oxidise petrol. So not an ideal replacement by the sounds of it.

Which suggests you need 18,000 tonnes of liquid air to store 1MW/h. The density is about 9/10ths that of water - so 20,000 litres roughly.

In gaseous form that is lots of air - hence you need to vent it rather than store it after use. It also means stripping the CO2 from "new" air each cycle.

With LPG you can burn the thawed gas to provide the heat of vaporisation

- and its only a small proportion of the heat stored. The same trick is unlikely to work for air!

[Tim Streater]

Well you're not burning the air unlike LPG - and for LPG you already need a largish tank. And what are the wind farm people expecting to do with the liquid air? Not, I hope, piping it anywhere. Are they just expecting to have yet more expensive equipment at the site of the wind farm with a low load factor?

[docholliday93]

Maybe they'll find somewhere to store the CO2 and claim to be carbon negative...

[Bill Wright]

But renewables don't generate excess energy. Even with all renewables going full tilt (which is unusual) the total output is nowhere near the UK's lowest demand figure. So if the energy from renewables was used at any time to power this storage scheme all it means is that gas-fired stations would have to work a bit harder.

Bill

[The Natural Philosopher]

Ah but once we have 60GW of solar panels on tap on harries house we will have a winters worth of energy to store!

I estimate that 3 moths of 10GW over the whole winter has the energy of

400 Hiroshima bombs. Just hope it doesn't let go all at once.

[The Natural Philosopher]

At 25% turnaround efficiency its still more fuel efficient to dispatch the power stations

[geoff]

In message , Tim Streater writes

Err, well, ... duh

you point it at the windmills and hey presto - perpetual motion