Electric Thermal Storage Heating
Electric Thermal Storage (ETS) is a heat storage technology which converts lower cost, off-peak electricity to thermal energy, or heat. An ETS system is odorless and exhaust free, and its heat is safely stored in specially manufactured, dense ceramic bricks. As heat is needed (either for domestic hot water or space heating), a blower moves the heat from the bricks to whichever application is called for.

Off-peak hours are those times of the day or night when electric power is generally less expensive. And to the degree that the electricity is derived from renewable sources like wind, hydro, biomass or tidal power, heating our homes, our domestic hot water and our businesses helps reduce Maine’s dependence on fossil fuels.

ETS equipment is easy to operate and requires very little maintenance. The amount of heat stored in the brick core of the heater is regulated (either manually or automatically) according to seasonal weather conditions. The on-board room temperature thermostat is set to your desired comfort level and controls the delivery of heat from the ETS heater. "Fan Forced" units, such as individual room heaters, have the ability to quickly discharge vast amounts of heat as required.

Thermal Energy Storage of Maine is the authorized factory representative for the Steffes line of ETS equipment. This equipment is available in a number of configurations to meet every type of heating need.

To learn more about ETS and how it can meet your home or business’s heating needs, please watch the informative three minute video.

Room Units
Room units are non-ducted heaters which are designed to heat the room or area into which they are placed. These heaters can be used in new construction applications or as a retrofit or supplement to an existing heating system. Various sizes of room units are available ranging from 1.32kW, 120V plug-in units, to the largest 10.8 kW, 240V models.

Forced Air Furances
These units are designed to be the main heating system (forced air) for residential or small commercial applications. The units can be used as a stand alone furnace or can be installed with a heat pump to realize even greater efficiency and energy savings. The Comfort Plus system has the heat storage capacity to provide total comfort 24 hours a day, while allowing the user to utilize low cost off-peak electric rates to achieve very economical and affordable heating. These units are easy to operate. The amount of heat stored in the brick core is automatically regulated in relation to outdoor temperature and the heating requirements of the user. When the room thermostat calls for heat, heat is extracted from the unit's storage core and is distributed evenly into the home until the heat call has been satisfied.

Hydronic Furnances (Forced Hot Water)
These systems add a new dimension to heating by blending hydronic heating with Electric Thermal Storage (ETS) Technology. Like all Steffes ETS heaters, the unit converts electricity into heat and stores that heat in specially designed high-density ceramic bricks located inside the unit. Using a heat exchanger this stored heat is transferred to a water or glycol solution which is then circulated to areas where the heat is needed. The Comfort Plus Hydronic system has the ability to utilize off-peak, time of day (or time-of-use), demand based, or other preferential electric rates to generate savings for the consumer while delivering the many benefits associated with hydronic heating.

The system is extremely flexible and can handle multiple heating zones (see application diagram example). Heat can be delivered via a radiant floor system, baseboard radiation, free standing radiators, a forced air system or almost any combination of zoned delivery systems. The Comfort Plus Hydronic system can also be used as a supplement to a single or multiple heat pumps. The Comfort Plus Hydronic system is easy to operate. Just set the room thermostat to the desired comfort level and enjoy the safe, clean reliable and economical heat this off-peak system provides.

Heat Pump Technology
Steffes ETS systems are the perfect complement to heat pump applications in colder climates. While heat pumps are known for attaining high energy efficiencies, as temperatures decline some form of electric back up heating is required. The use of lower cost off-peak power, stored as heat in ETS units, can assist heat pumps maximum their efficiency.

Cutaway of a forced air furnance