Waste Heat to Power Investment Tax Credit Act of 2019 This bill amends the Internal Revenue Code to include waste energy recovery property in the 30% energy tax credit, subject to a phaseout. The bill defines "waste energy recovery property" as property that generates electricity solely from heat from buildings or equipment if the primary purpose of such buildings or equipment is not the generation of electricity. Such property may not have a capacity in excess of 50 megawatts.