The Dearman Engine

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Sun 19 Feb 2023 10:57
The Dearman Engine - Adampr

I love a strange engine. Great viewing for others that do or, indeed, people interested in energy storage.

fb.watch/iNKoxOWerW/

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Sun 19 Feb 2023 18:37
The Dearman Engine - Xileno

I had never heard of Dearman but it's been around about ten years. I guess its applications are very limited perhaps explaining why it's not mentioned. Or maybe I've just missed it.

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Mon 20 Feb 2023 12:00
The Dearman Engine - Rotin

Good summary of the issues here.

en.wikipedia.org/wiki/Liquid_nitrogen_engine

A significant problem is the poor energy density of the fuel, typically you'd need a 350 litre tank to give you the range of a 50 litre tank on a petrol car.

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Mon 20 Feb 2023 19:24
The Dearman Engine - Terry W

Energy density - slightly better than or similar to current batteries.

Also like batteries the pollution comes from the manufacture of associated hardware and distribution + generating the fuel in the first place.

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Mon 20 Feb 2023 21:07
The Dearman Engine - Adampr

Energy density - slightly better than or similar to current batteries.

Also like batteries the pollution comes from the manufacture of associated hardware and distribution + generating the fuel in the first place.

Yes but, as he says, there are a couple of advantages over batteries. Firstly, no need for rare metals and secondly, no degradation in performance. I'm not convinced it will ever work for cars, but it's an interesting way to store solar or wind energy for when it's needed.

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Thu 23 Feb 2023 00:21
The Dearman Engine - Sofa Spud

I've seen an other videos about the same idea for an energy storage installation. One problem that was that nitrogen and oxygen, that are the main constituents of air, 'boil' at slightly different temperatures. Not sure why that would matter though.

As with renewable energy generation, a mix of methods is probably going to be the best solution for energy storage - i.e. battery installations, pumped water hydro, liquified air and possibly even super efficient flywheels (for dealing with short-term fluctuations in the grid's ability to meet demand)

Edited by Sofa Spud on 23/02/2023 at 00:29

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Thu 23 Feb 2023 06:25
The Dearman Engine - Brit_in_Germany

It could be a problem in cities if they cause the local ratio of N2 to O2 to rise.

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Thu 23 Feb 2023 09:12
The Dearman Engine - bathtub tom

possibly even super efficient flywheels (for dealing with short-term fluctuations in the grid's ability to meet demand)

There used to be a 'repeater station' on the A5 that was used to boost telecoms signals. The power supply consisted of an electric motor driving a generator via a ruddy great flywheel that had a clutch to a diesel engine. If the power failed, the clutch would engage the engine and the flywheel was supposed to have enough energy to start it. If the flywheel ever broke away, it was reckoned it would stop about forty miles down the A5!

I also recall reading about an experiment with (trams I think) that used a spinning flywheel for motive force. The flywheel would be 'spun up' at each stop.

Edited by bathtub tom on 23/02/2023 at 09:15

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Thu 23 Feb 2023 09:10
The Dearman Engine - Rotin

The volume of the liquified gas is a problem. 350 liters is about the capacity of the boot of a Golf. The tank would need to be even bigger than that to allow for the insulation.

Edited by Rotin on 23/02/2023 at 09:10

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