The article, “Litter-fired furnaces tested on the farm,” details the work of some researchers, entrepreneurs and poultry growers to develop litter-fired furnaces to heat poultry houses. In most parts of the country, poultry litter has some economic value, usually anywhere from $3 to $7 per ton loaded onto a truck or manure spreader on the farm. Poultry litter has around 10 million BTUs per ton, and at $5 per ton, a penny worth of litter would have 20,000 BTUs. At a propane price of $1.50 per gallon, a penny worth of propane would have 611 BTUs. Burning litter to heat poultry houses could bring back the era of “cheap” energy.
I must admit that I have a bias towards alternative fuels. I have an all electric house, so I put in a wood stove several years ago and I heat my house exclusively with wood that I cut on my property. I no longer have a heating bill, but I paid several thousand dollars for a woodstove, piping for my chimney and a log splitter. I also spend a lot of time cutting, splitting and stacking wood, Oh, and did I mention the covered storage areas that I built to hold four cords of wood?
I mention the wood burning example to illustrate what using litter as fuel could be like for poultry growers. Costs would include the litter furnace and shelter for the furnace, a means of conveying heat into the poultry house either with ductwork or piping, a storage area for the litter, equipment to move the litter and feed the furnace, and the labor to do the required litter hauling. I am not trying to rain on the burning litter parade, but it probably won’t be for everyone.
To date, the litter-fired furnace tests that I am aware of have involved furnaces sized to heat one poultry house, and they have been done on existing poultry farms. I have visited farms in the Western USA that use coal fired boilers to heat poultry and swine houses. Could a single large litter-fired boiler be used to make hot water which could heat several poultry houses? A single burner and hopper would minimize the amount of labor and would probably burn cleaner and more efficiently, because odds are that one of the houses would need heat just about all of the time. One way to minimize the cost of a project like this would be to do this on new construction.
High natural gas and propane prices coupled with a large number of poultry growers that do not utilize litter as a fertilizer on their own land make using litter as a fuel a potentially attractive alternative. With growers spending as much as $10,000 per house for heat using propane, the capital cost of a litter furnace might not be that hard a pill to swallow. If enough growers start burning litter, it just might reduce supply of litter to the point where its price for use as fertilizer goes up. Who knows, there might even be some kind of renewable fuel credit out there for growers who burn litter.