Re: Solar electric at 50% efficiency?


"Alex" <alexterrell@xxxxxxxxx> wrote in message
news:ec8e7269-53ba-495e-8d1a-993d6492980e@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Just a thought ...

Has anyone tried using solar thermal power as a pre-heater for thermal
power stations (gas or coal?)

Imagine a 20 Hectare solar collector field supplying about 200MW of
heat. This is used to preheat air and natural gas, prior to combustion
in gas turbines.

Input: 200MW solar and 800MW gas
Output: 500MW electric

Advantages:

- The heat is converted to electricity at an effective efficiency of
that of the plant, about 50% for gas turbines.
- The circulatory fluid is only heated to about 200-300C - quite
manageable with limited losses
- The heat can be stored in a molten salt and released when there's no
sun

Any problems with this?

For openers 20 hectares would see a peak power of 200MW with an insolation
of 1,000 Watts/sq M. That's peak, full sunshine. Averaged over a 24 hour
period, the insolation would be about 40MW. Secondly, the collection
efficiency would never be 100% so only about 30MW of average heat would be
available for preheat.

It would require strorage as you mentioned. To get to 200MW average, it
would take about 130 Hectares. And, as was mentioned it would be low grade
heat. At best it could only add a few percentage points to the efficiency of
the plant.


.

Relevant Pages

  • Re: What did you do to cut your carbon emissions Daddy?
    ... Peter wrote: ... The only way is to use less heat. ... I use wind power and I have a small water wheel - between the two I ... "As little as possible with gas. ...
    (uk.transport)
  • Re: Propane space heater - vented vs unvented???
    ... I have a gas fireplace but after it was installed, ... found that it was for show only and doesn't put out much heat. ... So far I don't remember ever loosing power here ... mounted propane space heater to use probably for emergencies only. ...
    (misc.consumers.house)
  • Re: Home heat w/out electric use
    ... What options are there for getting heat in the house with the electric ... Deep-cycle batteries and a power inverter to run the gas furnace and a few lights. ... Does the oven work without electricity You can use the oven set to a moderate temperature to heat the kitchen and surrounding rooms. ...
    (alt.home.repair)
  • Re: The power Went Out - No Heat....
    ... -> The power Went Out - There's not heat coming out of your furnace and ... I have gas heat. ... freezing cold it never stays freezing cold for long. ... I run out of gas. ...
    (alt.home.repair)
  • Coal Challenging Gas as Power Plant Fuel
    ... natural gas as the fuel of choice for new power plants. ... "The role of natural gas role in power generation is not a slam ... As each coal car reached the top of the incline, ...
    (comp.dcom.telecom)