If those numbers are correct for the original, and the summary is correct with its "250% more power at one third the cost", that would drop the new version to $11,000 / 3.5 / 3 = $1,047/kW, less than what you quote for coal (disregarding operating costs, which I have no idea of). Unless they mean the 250% extra works out to one-third the per-Watt cost, which would imply $11,000 / 3 = $3666, not bad but a bit pricey. Don't know which cost TFA refers to (old system or new one); anybody know?