will need millions of tons of metals and materials to build the batteries going into electric vehicles.  The Nevada factory will produce anode copper foil and cathode active materials, two key ingredients of lithium-ion batteries, from a combination of raw materials, scrap from sources including the nearby Tesla battery Gigafactory in Reno, and end-of-life batteries shipped in from across the country.  Energy efficiencyFoam panels can turn old abodes into energy-efficient homes of the futureSolarWant to go solar? These companies and groups are here to helpElectrification5 barriers to induction stove adoption — and one clever high-tech fixHeat pumpsChart: Americans bought more heat pumps than gas furnaces last year