That is not the point of the comment to which you're replying. They didn't claim that the purchase price provides a good estimate of the energy cost, but that i

That is not the point of the comment to which you're replying. They didn't claim that the purchase price provides a good estimate of the energy cost, but that it provides a strict upper bound. If the manufacturer is not selling at a loss, then they can't sell for less than their energy costs, let alone labor costs.