Caleffi. The SRCC-certified Solarie Solar Heat Pump is an all-in-one collector and storage tank system that eliminates the need for a separate backup water heater. Using demineralized water instead of refrigerant liquid as a heat exchanger, it pumps the water to its rooftop collectors only when sunlight is available, then drains the water to the holding tank during sunless periods. This prevents the system from freezing or overheating, even during power failures. When needed, water is heated automatically by a backup electric element or gas burner built into the tank. 414.238.2360. .

Rheem. SRCC-labeled Solaraide passive solar water heating systems operate without pumps or controllers. A closed-loop, indirect heat exchange design wraps completely around the unit’s roof-mounted thermo-siphon exchange tank for optimum efficiency. Single or double flat-plate collectors in 47- or 80-gallon capacity include multiflow risers that transfer heat rapidly and provide heated potable water directly to the home’s existing or backup water heater. The company also makes SolPak active solar thermal systems and storage tanks. 800.621.5622. .

Velux. Known in the U.S. for skylights and roof windows, Velux has been manufacturing flat-plate solar systems worldwide for more than 15 years. The SRCC-certified Integrated Collector Systems now available here can be installed directly onto the roof deck for a low-profile appearance using a flashing system that covers all mounting hardware. One-, two-, or three-collector systems with 60-, 80-, or 120-gallon insulated storage tanks are available. 800.283.2831. .