Definitions for Column Headers- Solar Water Heaters Product List

Brand and Model
This is how a particular water heater is identified. Manufacturers identify products they produce using the brand and model number. Some products may also be identified with a name or SKU, which is different from the brand or model number. You should always be able to find the brand and model number on a product.

Model numbers sometimes contain wildcard characters, such as *, #, and X, that are placeholders for non-energy attributes, such as color.

SRCC Certification #
The Solar Rating and Certification Corporation provides independent certification of solar water systems.

Active, or forced-circulation, systems use electric pumps, valves and controllers to move water from the collectors to the storage tank. Passive systems require no pumps. Natural convection moves water from the collectors to the storage tank as it heats up.

System Type
Forced Circulation systems use a pump to circulate the water or other fluid from the collector where it is heated by the sun to the storage tank. Integral Collector Storage (ICS) systems, or �batch� water heaters, combine the collector and the storage tank into one. Thermosyphon systems have a separate storage tank, located above the collector. Liquid (which could be water or an antifreeze solution) warmed in the collector rises to the storage tank.

Collector Type
Solar Water Heaters are available in the following collector types: batch, flat-plate, and evacuated tube. Batch collectors heat water in dark tanks or tubes within an insulated box, storing the water until drawn. Flat-plate collectors consist of copper tubes fitted to flat absorber plates. Evacuated tubes contain a vacuum of space around the metal or glass tube.

Collector Panel Area (square feet)
Refers to the total area consumed by the solar collector.

Solar Fraction (SF)
Solar Fraction is the portion of the total conventional hot water heating load (delivered energy and tank standby losses) provided by solar energy. SF is determined by the rating conditions and model outlined in the OG-300 standard developed by the Solar Rating and Certification Corporation (SRCC).

Solar Energy Factor (SEF)
Solar Energy Factor refers to the energy delivered by the total system divided by the electrical or gas energy put into the system. The higher the SEF, the greater the solar contribution to water heating, which reduces the energy required by the backup water heater. The SEF is presented as a number similar to the Energy Factor (EF) given to conventional water heaters by the DOE test procedure.

Freeze Tolerance Limit (F)
The limit to the system�s tolerance of freezing weather conditions.

Solar Tank Volume
Capacity of the tank, in gallons.

Min Warranty � Solar Collector (years), Min Warranty - Tank (years), Min Warranty � Controls (years) and Min Warranty � Parts (years)
Warranty is an assurance by the manufacturing partner that the purchased equipment and components are warranted for a certain required period-of-time, depending on the technology. Minimum warranty is the shortest warranty you can receive on the qualified water heater model.

Models that appear in parenthesis and in red are discontinued by manufacturers, but may still be available in stores. Discontinued models will appear on this list for a year after their last production date to allow retailers to clear inventory. These models are still ENERGY STAR qualified, but they are no longer manufactured. Sponsors, such as utilities, may honor incentives for discontinued models at their discretion.