Did you know using sunshine to heat or preheat your water can reduce your annual water heating costs by 50 percent?* Residential customers of FirstEnergy's Ohio utilities can earn a $375 rebate for purchasing and installing a qualifying solar water heater. The water heater must have a Solar Energy Factor (SEF) greater than 1.8 and be installed by a participating contractor.** Customers are only eligible for one rebate per unit during the Program Period (March 1, 2018 – September 30, 2020). Rebate applications must be postmarked or submitted online by September 30, 2020.