Majority (30%) to electricity then transportation industry commercial and residential agriculture at 9% U. s. electricity consumption directly correlated with per capita gdp generally has been steadily increasing since 1960. Generating and transmitting electricity the power grid: generation plant step-up transformer transmission lines step-down transformer pole transformer first u. s. grid in 1927 electricity basics two forms of electricity. Direct current: used in batteries alternating current: used in most power grids current: electricity in transmission voltage: how much force pushing through transmission chemical energy in a fuel like coal, when burned: 65% initially lost as heat during combustion. Power generation either has to be close to power consumption or else use battery storage. Energy options total u. s. electricity generation by source natural gas (33%) coal (32%) nuclear (19%) nonhydro-renewables (8%) hydro (6%) coal is fossilized energy four basic ranks (from lowest amount of carbon to highest) lignite subbituminous.