Compliments to “High-Efficiency Home Heating” (HP157) author Scott Gibson for the research, and for simplifying this topic down to useful information that we can use to compare apples to apples. I’d like to add some thoughts in addition to those in the article as to, “How do we define, and what do we consider to be true efficiency.”
The most important aspect of a heating system is to “get the heat to the person without heating the rest of the house or the outdoors.” That being said, the optimal system is not necessarily the one that has the highest efficiency rating, but rather a combination of unit efficiency, individual thermostatically controlled rooms, efficient distribution (ducts or individual room heat), a heat recovery ventilation (HRV) system, and ease of locating/installation. I believe that every new home should have an HRV system to save heat that would otherwise be lost due to required house ventilation. The tighter a house is, the more important whole-house ventilation is.
Now, we have to look at how to control the individual rooms so that we are heating the rooms where people are, instead of heating the whole house with a single thermostat. The best way to do this is to use an individual heat source in each room. My preferred method is to use a electric radiant ceiling panel system.
With radiant heat you heat objects instead of the air. The occupant will instantly feel the warmth, just like stepping into the sunshine. It is also instant on/instant off. It can be controlled with a thermostat in each room as well as an on/off switch that can be turned off when leaving the room, and with a whole-house switch at the front door. Radiant heat from above is the best way to go in my opinion, and I have yet to see a more “efficient” system. True, it does use electricity, but I would recommend solar-electric modules on the roof and super-insulating the walls to have a true net zero-energy house.
Forrest Jones via homepower.com
I think it is important to point out that electric radiant ceiling heat is still electric resistance heat, which is expensive energy for consumers in many parts of the country. When a homeowner is heating with radiant ceiling elements, there’s no way to take advantage of off-peak rates. If you need heat during the day, when electricity is at its most expensive, you just have to turn the system on. The electrical thermal storage units described in the article also run on electric resistance heating, but the idea is to charge the systems when power can be purchased at off-peak rates.
Zoned heating is indeed more efficient because you can heat only those areas that are being used. But if each room in your house has its own radiant-ceiling heating element, you’ll have to turn up the thermostat every time you move around.
Electric radiant systems embedded in the ceiling are more difficult to repair than many other types of heating appliances. And heat-recovery ventilators reduce the energy penalty of whole-house ventilation, but they are not related to how heat is produced or distributed.
In a well-insulated house that has very little air leakage, almost any type of heating system can be used at a relatively low cost, even electric resistance heat. That’s the premise of the Passive House standard and it’s why reducing heating and cooling loads is so important. But for many homeowners, who live in relatively leaky houses with too little insulation, electric heat is an expensive option.
Scott Gibson • Home Power contributor