<t>One is temperature differential. The more the better because the <br/> maximum efficiency is TH-TC/TH*100. Degrees Kelvin of course. <br/> Example TCold = 300K (27C)<br/> THot = 500K (227C)<br/> Maximum efficiency = 500-300/500 * 100 = 40 Percent absolute max.<br/> Power almost varies as the squa...