Solar Heater (cogeneration Technology) in Place of Preheaters

MOST operate during the day?????? I thought every last one of them did

Whether the system will produce steam or not is function of the sun radiation and the flow rate of your liquid through the pipes.

Is it cost efficient? - Yes

This technology is designed for using the fluid to remove heat from the PV cells, thereby improving their efficiency. Although your suggestion to use this heat to preheat the boiler feedwater is valid, it ignores the fact that the entrance temperature of the feedwater to be heated may be too high to allow the PV cells to operate within their specified efficiency range.

That's not to say that it can't be done, just that it needs to be viewed in the overall heat balance and operating parameters of the CSP plant.

On the practical side of things.....

You should study the specifics regarding feedwater heaters in a Rankine power generation cycle.

In this cycle, steam is bled from the steam turbine and used to preheat the condensate (feedwater) returning back to the boiler. This is accomplished in very large shell & tube heat exchangers. It is highly desired that the returning condensate is at an elevated and constant temperature. This ensures that stable boiler operation is achieved and emissions maxima are not exceeded.

The feedwater must be delivered at high pressure to the boiler via boiler feedwater pumps.

The required temperature of the steam bled from the cycle exceeds that possible from CSP collectors. The operating pressure of the cycle exceeds the design pressure of the CSP collectors, which are typically constructed to operate at very low pressures.

The required massflow of the feedwater in a typical power plant is very large.

The only possible thermal "place" for a CSP device in most modern Rankine cycle plants would be to preheat makeup water fed into the plant deaerator. This is an application for low-grade heat.

Sorry, its a nice idea..... the laws of thermodynamics are brutal.....but universal

http://en.wikipedia.org/wiki/Rankine_cycle

In a book titled "Modern Inventions" that was published in 1903 was a solar powered steam generator. It was parabolic reflector lined with a thousand mirrors with the steam boiler in the middle. It looked a lot like a modern radiotelescope. It's output was about five horsepower. It was located in Arizona.

I prefer the system that is based on inflatable mirror combined with pvc.

Look for coolearthsolar.com.

Thanks for all your views and ideas.

@DvnDsc, this technology won't produce steam. it can heat water upto 120 degree centigrade. i was thinking for small capacity power plants.

@Ramconsult, your point on operating characteristics of PV module is good. i will look into that one.

@Anonymous, good analogy. you are right, the pressure will be too high for CSP collectors. using it for preheating makeup water !! will study this.

Thanks again, let the ideas flow in......