Energy efficient pellet stoves

New pellet stoves are very similar in their appearance and technological elements to new wood-burning and gas stoves. They are more expensive than wood burning stoves, but they are more energy-efficient and also cleaner and easier to maintain and to use.

Pellet stoves fuel & Ash

Pellet stoves burn biomass materials, namely wood and corn pellets. But be aware. Pellets use with different formulas (different types and combinations of wood) and the efficiency of stoves varies according to the quality of the pellets.

Ash is an important element to assess the quality of the pellets: premium pellets have less than 1% of ash content, while standard pellets have about 3%...

Pellet fireplace, from Lennox manufacturers It may important to choose a pellet stove that burns a very wide range of pellet fuel.

Sizing for a better efficiency

The efficiency of pellet stoves depends on a proper sizing, which in turn depends on your climate and on the insulation and sealing levels of your home, and the size of the area you want to heat.

Here is a very rough set of thumb rules often use to size a pellet stove:

- Warm areas (south USA, for instance), well insulated homes: 15 BTU/sq. foot (160 BTU/m2)
- Warm areas (south USA, for instance), poorly insulated homes: 25 BTU/sq (270 BTU/m2)
- Very cold areas (Canada, for instance), well insulated homes: 25 BTU/sq. foot (270 BTU/m2)
- Very Cold areas (Canada, for instance), poorly insulated homes: 35 BTU/sq. foot (375 BTU/m2)

For areas between the Warm and the Very Cold you should consider an intermediate value and multiply it by the area of the home to be heated.

The efficiency of pellet stoves

New pellet stoves are so efficient and pollute so little that, in USA, the EPA has only a voluntary scheme of certification (some new models produce less than a 1/2 gram of emissions per hour).

But having a certification label is important. It means that the stoves are very efficient and environmentally-friendly.

Installation

Pellet stoves are usually direct-vented through a wall (or the ceiling). Venting is very similar to that of gas-burning stoves.

See: Direct-vent vs. B-Vent

Features to consider in efficient pellet stoves

If shopping, pay attention to the features of the stove. Take into account its size, emissions and efficiency, but do not forget other key features like…

- Controls: to adjust feed rates, start-up, consistency, and to control the burning process.
- Blowers; to force hot air into the rooms.
- The storage capacity of the hopper: the quantity of pellets that can be stored by the stove and is automatically fed to the combustion chamber.
- “Fully” automation (involving the hopper);
- The variety of pellets that can be burned: a wide variety is a good sign;
- Ease of operation: with a good pellet stove you just need to add pellets and turn it to the desired temperatures (though pellet stoves will always demand more care and maintenance than a wood or a gas stove).
- Quietness of the motor and fan. A well insulated double-cushioned combustion fan is important for efficiency and quietness; pellet stoves can be noisy...
- Completely sealed combustion (100% outside air);

Alternatives

The new gas and the new certified wood-burning stoves are the more direct alternatives to pellet stoves. They are also medium heat output appliances, capable of replacing other more expensive options, namely central heating systems (see: Heating Solutions with stoves).

New certified wood-burning stoves have the advantage of lower running costs, but they are less easy to maintain and are less clean.

As to the gas alternative, the cost of the gas of the gas vs. the cost of the pellet in your area can be the more defining element…

For a comparison of the heating costs of the different fuels, see: Heat Calc NEIC (Excel Sheet) or Pellet Fuels Institute .