New Mars Forums

Official discussion forum of The Mars Society and MarsNews.com

You are not logged in.

Announcement

Announcement: This forum is accepting new registrations by emailing newmarsmember * gmail.com become a registered member. Read the Recruiting expertise for NewMars Forum topic in Meta New Mars for other information for this process.

#251 2024-09-19 15:21:30

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 3,724

Re: Thermal Energy Storage

I have done some back of the envelope screening calculations that tell me that TES is an expensive option if we use it to store electricity that has already been generated.  The way to use this is either as: End use energy storage; or (2) To store primary heat prior to generation.  The first option is how a water storage heater works.  There is lots of heat using equipment that can heat as an end use.  An example of the second is TES employed at a solar thermal powerplant to allow continued generation at night.

********************************************
Total costs.

1GWe steam plant: Capital cost = $1bn
3GWd(e) (7.5GWd(th)) salt storage: Capital cost = $4.5bn
Marginal annual capital cost: 10% total = $550m/year.
Operating cost = same as marginal capital cost of steam plant ($100m/year).

Power cost.  Assume that half of all power generated goes into the store and 40% of what is stored is recovered.  Therefore, the store consumes 0.5GWy of electricity and produces 0.2GWy.  Power input cost = $0.1/kWh.

Total power consumed = 0.5 x 1000,000kW x 24 x 365.25 = 4,383,000,000kWh
Total cost = $0.1 x 4,383,000,000 = $438,300,000/year

Total cost = $1,088,300,000/year.

Power generated = 2/5 x 4,383,000,000 = 1,753,200,000kWh/year

Cost per kWh= $ 1,088,300,000/1,753,200,000 = $0.6207/kWh

For the 0.7GWy that reach the grid, cost will be:

(0.5 x 0.1 + 0.2 x 0.6207)/0.7 = $0.249/kWh.

That is expensive, considering we started with a power cost of $0.1/kWh.  If the heat store can be used to store primary heat gathered from the sun, the economics are a lot more favourable.  End use heat storage is better still.

Last edited by Calliban (2024-09-19 15:30:49)


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

Offline

Board footer

Powered by FluxBB