Nuclear Air Compressor (Hybrid Nuclear Power)

[MattNCSU03]

A colleague of mine sent this to me--the idea combines a helium reactor with a combined cycle fossil plant and claims 50% efficiency.

An interesting idea, who knows if it will take off...

http://www.powergenworldwide.com/in...wide/nuclear/equipment/2011/01/NPI-Paper.html

 

[davefitz]

An interesting article, but I do not not see how using the helium turbine's shaft power to compress the CTG 's air is of more benefit than using the same shaft power to produce electricity.It seems like a zero sum game.

First of all , about 2/3 of a gas turbine's shaft power is used to compress the air, not 1/2. Secondly, modern combined cycle plants already can exceed 60% LHV efficiency. And finally, a modern coal fired plant may be able to achieve 50% LHV efficiency, when they combine higher final steam temperatures with a double reheat supercritical steam cylce plus use the "Master Cycle" configuration with a "tuning turbine".

With regards to combustion turbines, a more timely improvement would be to use CAES compressed air energy storage to cope with the need to offset quickly changing distribution system inputs caused by upsets in renewable energy outputs ( witness the Texas system's widespread upset that ocurred when all ERCOT wind turbines tripped offline due to a wind speed increase from 55 mph to 55.00001 mph 3 yrs ago, losing 1400 MWe in 30 minutes).

With regards to nuclear power, perhaps a better combination would be to use the small compact nuclear reactors to produce saturated steam , while the economizer duty and superheat duty could be achieved by a HRSG downstream of a CTG gas turbine- this reduces the increase in entropy that occurs in a normal HRSG due to the large thermal duty needed to boil steam at cosntant temperature , which normally implies a need to increase the temperature differnece during evaporator heat transfer. But historically one has not been permitted to use natural gas at a nuclear site.

Perhaps a bigger issue with nuclear power may be the potential for china to develop a thorium cycle based industry, and leaving the western countries behind in that particular area.