Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

As the efficiency of PV thermal or wind energy decreases with time(from the installment). Is there any mathematical model that gives its relation with time. i.e., whether it is a linear decrease or some other function of time.

I need to use the result of this in my research on energy markets.

share|cite|improve this question
I know PV as photovoltaic, what do You mean with it? – Georg Nov 10 '11 at 14:20

If you properly maintain something -- a solar thermal power plant, a factory, anything -- it will last forever. You just need to replace each part when it's sufficiently worn down.

If someone builds a solar thermal power plant today and you ask me what that plant's efficiency will be in ten years, I would guess that the same plant would be more efficient, not less, because the company will have invested to not only maintain the plant in good working order, but also to improve its technology as it goes. For example, when the mirrors get scratched and dirty after a few years, the company might replace the mirrors with new mirrors that have a better coating technology than the original mirrors.

There is a big difference here between a utility-scale plant being maintained for long-term performance by professionals, and (say) a solar panel on my roof, which I do not have the time or expertise to maintain. A solar panel on my roof will only get more and more scratched and dirty and degraded over time. So its efficiency will go down and down, in a way that can be predicted and modelled.

It might be the case that it is not worth maintaining a solar thermal power plant in good working order. Maybe it's cheaper to let it get worse and worse, then throw everything out and rebuild it from scratch. I doubt that's the case! But if it is, the decay function is not something a physicist can predict from his armchair. You probably need to ask an engineer in the industry.

share|cite|improve this answer
thanks that was very helpful. I am looking it from the perspective of supplier in an energy market. Now I think, I can safely considered it(supply from non-renewable source) to be a constant following your argument. – ghost-rider Nov 10 '11 at 15:10
But again I need to consider the expenses as it affects his bidding rates. Probably I need to get data from some industry may be I can build a empirical model and come up with some equation. – ghost-rider Nov 10 '11 at 15:14

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.