The Reference Frame: RICS: Solar panels pay back in 100 years

Obviously, they can't improve RICS' numbers because these numbers are qualitatively correct and the completely correct ones still imply that the investment is silly from an economic viewpoint. Because the maximal lifetime of the solar panel systems is 30 years, it's clear that you will never get the expenses back. Therefore, you won't hear any "better calculations" from them.

So they at least emit some fog about the different "types" and they argue that if the energy prices rise 20-fold, it will actually only take 5-10 years to recoup the money instead of 100-200 years. Also, if the taxpayer pays 50% of the costs, it will only take 50 years for the house owner to get her money back. ;-) Good arguments, indeed.