Einstein was first to invent the fridge, he used a boiler to raise liquid to high pressure gas which is then blocked by restrictor plate forcing the gas through a tiny hole so it loses all it energy and passes through to the other side a low pressure liquid due in part to gas passing into a large vacuumed chamber. The vacuum draw on the cooling chamber is maintained by the screw pump which also acts  boiler pump.

The advantages of this design is the gas cooling chamber is immersed in cold liquid inside the boiler. The heat shed by the hot gas in the cooling chamber turning the hot gas to cold liquid is taken back in absorption by the cold liquid phase changing into high pressure gas.

Having the turbine also in the boiler means and heat leak from the turbine also gaoes as heat assisting the cold liquid to high pressure hot gas.

To contain the all the forces arising from CO2 at heat of 0*C  up to 100*C  Stainless Steel is used in onstruction.

Other materilas may be used where pressure is more confined to lower heat.

Sorry dont know why it appears to had been taken away, its till there. Please also note the -100*C shoud read +100*C

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Not trialed only text book data.  All available web. The wattage required to heat one litre of water x degrees in one second is less than the turbine wattage output if high pressure gas is involved.  This requires construction using Stainless Steel to withstand the pressure forces. Such a system however would need CO2 liquid to heat at the same rate as H2O or the CO2 be heated by passing through hot water.  CO2 heating through water requires removal of the gas cooler from the gas boiler.