8

From mining/harvesting materials to altering them into useful manufacturing materials to making actual products, and then packaging them and shipping them to retail stores, or directly to customers, and then the time and energy it takes to mount them (especially on larger scales eg. fields), do they really put out enough energy to outweigh all that?

marked as duplicate by EnergyNumbers May 27 '16 at 5:04

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

  • I think this is effectively a duplicate of this - an answer there, would answer the question here. – EnergyNumbers Aug 25 '14 at 8:45
  • 1
    Annoying, can't mark it as a duplicate because there's no an answer (yet). Although this is a simpler question, a valid answer is "yes" :) – Móż Aug 26 '14 at 6:07
6

I asked my late father (an electrical engineer) this very question years ago and he said that essentially, the entire cost of a solar panel is the cost of the energy to make it. You dig dirt out of the ground and apply energy to turn that into metal, glass, etc, then you use energy to ship parts around and to assemble them into a panel and ship the panel, etc. The cost of the true raw material is very low indeed and the cost of the factory is again the cost of the energy to make the factory, and so on down the line. The possible exception may be a retail markup and a labour cost when you finally acquire and install it.

Now, consider that solar panels "pay for themselves" in the end. You pay $X for a panel and after some number of years, you have saved $X in energy bills. It therefore follows that it has generated at least as much energy as it cost to make it. This logic would only fail if you pay a wildly different cost for energy than everyone before you in the chain. Aluminum smelters do locate near dams to get cheap power, but I don't think you'll find that cheap means "1/10th the price" or even "1/2 the price" so the logic holds. Any panel that is economically worthwhile has produced more power than it took to smelt and refine its materials and to make it, as measured in dollars.

  • Actually wholesale prices for electricity can be 1/10 of the retail price or lower. Tiwai Point aluminium smelter pays about 1/4 retail, for example. – Móż Oct 21 '14 at 1:46
  • 1
    For some actual numbers on this, see this question on Skeptics: skeptics.stackexchange.com/q/27394 – Kate Gregory Apr 18 '15 at 14:44
  • Panels are generally not economically worthwhile without subsidy – D J Sims May 26 '16 at 23:08
  • 1
    @NeilTyson Generally is probably too general. In NZ (not vastly different to US) a case may be made for a sensible PV installation. IOt is possible to pay too much and get too little but paybacks inside system lifetime using proper rate of return calculations are possible. – Russell McMahon May 29 '16 at 8:17

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