Stiebel Eltron’s Accelera 300 heat pump water heater is Energy Star certified and rated. The heat pump draws only 500 watts and can be tied into a PV system. With backup element (+1,700 watts), a grid-tie may be needed, but with a full tank (80 gal.) at 140° F and a 76.2-gal. first-hour rating (2.73 EF), daily hot water needs may be satisfied without the backup element. The annual energy usage is only 1,391 KWh/yr. At 12 cents/kWh that’s just $167 per year. The water heater comes with a 10-year warranty. Call 800/582-8423 for more information.