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grain-burning stove





Envirotec grain-burning stove
Envirotec Model 5775 grain-burning stove
A stove similar to an ordinary wood stove in appearance that is specifically designed to burn grain. Grain is a good, renewable fuel, but requires special conditions to burn effectively. It is also very cheap in "breadbasket" regions of the world, including Canada and the American Midwest, where the grain doesn't have to be transported far. Therefore, many customers for this type of stove are rural folk, especially farmers, who live in these regions. Note that grain-burning stoves do not have to burn "food as fuel." They are most effective, both environmentally and economically, when using unmarketable or grain, which would otherwise be wasted.

Typically, a grain-burning stove can use all grades of hulled wheat, rye, triticale, peas, faba beans, and corn, as well as other biomass fuels, such as cherry pits and wood pellets. It's recommended that the grain be cleaned before use. Oil seeds and grains with high hull content such as barley and oats don't work well in the stoves.

As in the case of all heating appliances that use biomass fuel, if you don't have your own supply check on the availability and cost of grain in your area. When deciding which particular stove to buy, look carefully at the manufacturer's recommendations and the stove's features. Make sure that the stove is designed for burning grain and similar materials and of the grade you intend to burn.

Expect to burn up to one bushel per day, or about 150 bushels in total in the heating season (one bushel of wheat weighs about 27 kg or 60 lb). This figure will obviously vary depending on the size of the home and the type and quality of grain being burned.


Grain as a fuel

Compared with wood pellets, grain is denser, has a much higher water content, and comes in a greater variety of types. It is for these reasons that a grain-burning stove, although generally similar in the way it works to a pellet stove, must be purpose-made, with controls and mechanisms that enable different kinds of grain to burn efficiently. With some adjustments, a grain-burning stove can also be used to burn pellets, but the reverse is not true.

Grain begins to burn at a temperature of about 1100°F (593°C) but before this can happen all the moisture must be driven out, a process that takes place at the boiling point of water – 212°F, or 100°C. Grain containing more than about 14% moisture won't generally burn unless it's mixed with drier or more easily combustible grains.

An important aspect of a grain-burning stove is how effectively, once the grain is burning it burns through completely. Some means is needed to make sure that unburned and still moist grain is able to catch fire. Typically, this involves some mechanism for agitating the fuel, such a stirring stick, or by having a burning pot that allows air to reach the grain through appropriate sized holes.


Cost comparisons of burning grain and other fuels (based on Jan. 2006 rates)

Fuel type BTU value per unit Units required to produce 1,000,000 BTU Fuel price per unit (approximate) Total cost to produce 1,000,000 BTU Effective cost to produce 1,000,000 BTU Additional cost of using other heat sources
Grain 9400/pound 106.4/pound =1.9 bushels $2.00/bushel $3.80 @92% efficiency = $4.13  
Electricity 3413/kWh 293/kWh 12.06 cents/kWh $35.35 @100% efficiency = $35.35 8.6 times more
Natural gas 345.94/cubic meters 28.17 cubic meters $52.20/cubic meters $14.70 @85%efficiency = $17.29 4.18 times more
Fuel oil 37,549/liter 26.63 liters 83.90 cents/liter $22.34 @70% efficiency = $31.92 7.72 times more
Propane 24,035/liter 41.6 liters 49.9 cents/liter $20.76 @ 70% efficiency = $29.64 7.18 times more
Wood 16,464,000/cord 0.0607 cords $200/bush cord $12.14 @60% efficiency = $20.23 4.89 times more
Wood pellets 7800/pound 128 pounds (0.0651 tons) $237.50/ton $15.22 @ 80% efficiency = $19.02 4.6 times more


Environmental benefits of grain-burning stoves

  • No creosote
  • No harmful emissions
  • Uses renewable/sustainable fuels and is therefore carbon dioxide neutral (zero net effect of CO2 levels
  • Decreases dependence on fossil fuels
  • Virtually no waste (2% ash compared with about 15% ash from a wood stove). The remaining ash contains potash and other minerals, which can be used on gardens and flowerbeds
  • Utilizes lower quality grains, including damaged crops that are useless as food

Related category

   • FIRES AND FIREPLACES