Quote from: colinistheman on July 25, 2013, 11:58:14 AM

Quote from: DeathAndTaxes on July 25, 2013, 08:06:31 AM

Solar isn't free. You are simply buying the lifetime power output up front.

(Total purchase costs + total lifetime maintenance cost) / (lifetime power produced = cost per kWh.

That's true. You're right, it's not free. It just gets less and less expensive the longer it runs... but it could need replacement too. I suppose I didn't look at it this way-- thanks. You have helped me come to grips with the modern power grid and not waste my time and money lol

Well it isn't they "may" need replacement. Solar panels have a finite lifespan. Even excluding things like damage due to hail, wind, etc the panels will slowly lose output. Not electronic circuit will last forever. Every single solar panel ever produced (and everyone one which will be produced) will eventually become worthless. Now the lifespan is measured in decades (most panels have a 20 yr or 30 yr rating) but the output will slowly degrade, a 0.25% to 0.5% drop in output annually is a good starting point. The inverter generally won't last more than a decade. It is under a lot of stress and heat. Even a high efficiency one say 94% means 6% is converted into heat and 5KW * 6% = 300W which is a lot of heat for 24/7 operation over a decade). Add to that annual maintenace (cleaning panels, replacing frayed wiring, checking connectors, etc) and it is hardly infinite power with no additional work/cost.

Solar power is simply a source of power. With the right prices, right location (amount of solar insolation) and right subsidies it can be cheap power (well cheap for you paid on the backs of taxpayers) but it is still power at a certain cost. Another thing to consider is cost of capital. With a solar power plant (much like a nuclear power plant) most of the cost if upfront. This means you are essentially buying 20-30 or even 40 years of power on day 0. If your return is low say 3% return (lifetime cost is 3% lower than buying grid power on an annualized basis) it may be "cheaper" to invest that money and earn a return of say 6% and use that to buy grid power.