22 minutes: Conference presentation at the 2012 American Society of Mechanical Engineers (ASME), International Mechanical Engineering Conference and Exhibition (IMECE). Humanity's Grand Challenge is transforming the world's largest industry from ~ 80 % fossil to ~ 100 renewable, CO2-emission-free energy sources, as quickly as we prudently and profitably can. We cannot do that -- and should not try -- with electricity systems alone; electricity may be technically and economically suboptimal vis-a-vis complete, optimized, renewable energy systems based on Hydrogen (H2) and Ammonia (NH3) Carbon-free fuels via underground pipelines, accessing seasonal-scale energy storage at < $ 1.00 / kWh capex: H2 in "packed" pipelines and deep underground salt caverns; NH3 in large, refrigerated "atmospheric" tanks.