

Liquid air 'offers energy storage hope' - Zenst
http://www.bbc.co.uk/news/science-environment-19785689

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ksec
Surely you would need energy to chilled the Air to Liquid?

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rprasad
Important to note, which the article does not, that substances which are
gaseous at room temperature are chilled to liquid using excess energy (i.e.,
energy produced at night). These liquids are stored chilled in vacuum-
insulated canisters. These liquids are then brought up to room temperature
when needed, and their expansion into gas drives a turbine. Presumably, no
external power sources (or only waste heat) is used to warm the gases.

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Zenst
I dunno I thought there outline covered that:

" The process follows a number of stages:

1."Wrong-time electricity" is used to take in air, remove the CO2 and water
vapour (these would freeze otherwise) 2.the remaining air, mostly nitrogen, is
chilled to -190C (-310F) and turns to liquid (changing the state of the air
from gas to liquid is what stores the energy) 3.the liquid air is held in a
giant vacuum flask until it is needed 4.when demand for power rises, the
liquid is warmed to ambient temperature. As it vaporizes, it drives a turbine
to produce electricity - no combustion is involved "

There is even a mention of using waste heat from other sources to expand the
gas further.

