Common Questions About “Electric Thermal Storage” (ETS) Heating
1. “I have never heard of Electric Thermal Storage before. Is this something new?”
Electric Thermal Storage (ETS) heating has been used in the United States since the early 70s, and has been utilized in Europe since the 1940s. This technology has been proven in some of the coldest climates in North America to deliver great comfort. When combined with a preferential off-peak heating power rate, such as the one recently adopted by Madison Electric Works, its lower operating costs make it an attractive, cost-saving option for space and water heating purposes.
2. “How does it work?”
An ETS unit uses low-cost, separately-metered off-peak electricity to heat specially manufactured ceramic bricks within the unit. The heat stored in the unit provides thermostatically-controlled space heat for homes and businesses around the clock. Many utilities, now including Madison Electric Works, have adopted off-peak heating power rates that provide great savings versus the standard “all hours” electric rate ETS equipment available today includes supplemental room heating units, whole-house forced-air furnaces, heat pump boosters, hydronic furnaces and water heaters.
3. “How can ETS technology be applied in my home or business?”
There are several ETS options available for homes and businesses. Individual room units can be used either alone or in conjunction with other systems, such as electric baseboard,, etc. Room units can replace wood stoves or kerosene heaters that currently supplement existing systems, such as forced hot water baseboards. Large, centrally ducted ETS units can replace existing oil furnaces for whole-house applications, and can be used in conjunction with a heat pump to offer even better efficiencies and lower operating costs. ETS-powered hydronic systems can provide in-floor heating, tie into a hot water baseboard system or radiators, and can even provide ducted forced-air heating. Lastly, domestic hot water heaters can be integrated with ETS systems, saving you money on your water heating needs. Since space and water heating generally consume the most energy in the home, significant savings can be realized using ETS equipment combined with off-peak electric rates now provided by Madison Electric Works.
4. “I have a 1000sf home. What size equipment do I need?”
There are several factors involved in determining the correct size(s) of equipment for your application. A heat loss calculation should be performed to determine the appropriate model(s). The size of the area, construction detail (insulation values), number and size of windows and doors, and the number of off-peak hours available from your utility are all factors involved in making this determination. Using a Steffes room heater as a supplement to an existing system simplifies this task. Your authorized Steffes ETS equipment dealer can help you choose the model that is right for your home or business.
5. “Where can I purchase ETS equipment?”
Campbell’s Building Supply in Madison offers a variety of Steffes ETS units from which to choose. Either Campbell’s or Madison Electric Works can provide you with the names of electricians trained to install Steffes systems.
6. “How much does it cost to operate ETS equipment?”
Madison Electric Works has adopted an off-peak rate that is just under $0.07/kWh. That equates to oil at approximately $2.20/gallon. And remember, ETS heating is 100% efficient.
7. “How long will the 7-cent rate remain in effect?”
At least until December 31, 2013, or in other words, for the next two and a half years. Meanwhile, Madison Electric Works will be working to develop a low heating power rate that extends beyond that.
8. “How long will the ETS equipment hold heat?”
If sized properly, the equipment can provide the desired level of comfort 24-hours a day The heater’s brick core, which is used to store the heat, is well insulated so static heat dissipation is minimized. The heating equipment has the ability to discharge heat even while it is charging or storing heat during off-peak hours.
9. “What happens if the unit is charged up, and I don’t need heat? Is that heat wasted?”
ETS room heaters are well insulated so the majority of the heat is retained in the brick cavity until needed. An outside temperature sensor tells the unit’s digital controls just how much to charge every night, so in the so-called “shoulder months” the units charge less than during the coldest part of the winter. Operation is fully automatic.
10. “How do I get the heat out of the heater?”
Just like any heating system, a customer-controlled room temperature thermostat is set to the desired comfort level. Heat calls from the thermostat trigger the unit to discharge its heat into the area either by operating a blower to circulate air or by operating pumps to circulate water, depending upon the type of system being used.
11. “What happens if I run out of heat?”
It is important to size ETS heaters appropriately to ensure you have adequate storage to meet the heating requirements of the area, especially if you’ve installed a whole-house system. However, if you’re using an ETS room heater as a supplemental source of heat, with your existing system as back-up, this situation should never arise.
12. “What is the life expectancy of the heater?”
Steffes ETS equipment is designed to provide many years of trouble-free operation to you. Life expectancy depends on proper sizing, installation, and the environment it is operating in. Steffes heating systems have proven to be very reliable and all heaters have a five-year limited manufacturer’s parts warranty. Here in Maine, many heaters installed by CMP and Bangor Hydro during the l980s are still running well and keeping homeowners warm.
13. “Can I install the heater myself?”
No. ETS heaters are 240V directly connected heating appliances and require a second meter, which Madison Electric Works will provide. Licensed electricians are required to do the installation to ensure all local, state and federal electrical and safety codes are adhered to. Madison Electric Works can provide you with the names of local electricians who have been trained to install and service Steffes heating systems.
14. “I would like a different color heater than what is offered. Can I paint the heater?”
The heaters are painted with a specially formulated high-grade urethane powder paint that is baked on to provide high scratch and stain resistance and easy to clean finish. The neutral colors selected blend with most any background decor. Although the heaters can and have been repainted in the field, painting over the factory paint will not provide the same durability and performance.
15. “What type of maintenance is required?”
Like most electric heating systems, ETS systems require very little maintenance, if any. It is suggested to regularly clean around the heater and make sure no debris falls behind the equipment. Unlike existing oil furnaces, ETS systems do NOT require annual maintenance or tune-ups.
16. “Can I recess the room unit into a wall?”
Yes; however, the specified minimum clearances as listed in the heater manual must be adhered to. Failure to comply with stated clearances may cause operational difficulties, risk of fire, injury, or death.
17. “Does ETS store ‘COLD’ in the summer time?”
No. An ETS heater is strictly a heat storage device. Cool storage requires a different storage medium currently not developed for use in the average home.
19. “Can I install the equipment in my garage or workshop?”
Since this environment is prone to more dust and airborne particles and may have varnish, paint or other odors present, caution is recommended. Odor amplification and sooting issues can occur more readily in these types of environments. For this reason, Steffes does not recommend ETS heating in these types of applications.
19. “Can I run my ETS heating system on a generator?”
Yes, but the generator must be properly sized for the amount of load connected to it. It is generally recommended to only power the blower/controls/pump circuit from a generator as the charging (element) circuits are large loads and require a significantly sized generator to handle their requirements. However, by powering the blower/controls/pump circuits from a generator, the heat stored in the bricks can still be used to satisfy heating requirements during a power outage.
20. “Can ETS units be used with Renewable Energy Resources?”
Yes. Since Steffes heaters are storage devices, they can serve as a battery to harness renewable power generated from sources such as wind or solar. Steffes heating systems help fully utilize these variable generation resources to provide environmental benefit as well as help reduce our dependence on foreign oil imports.