Biogas from farm digesters is a valuable resource that provides energy savings and added profits.

Using the methane produced in a manure digester to fuel an onsite power plant is now practical and profitable for a growing number of livestock producers, dairies, and finishing farms. This renewable source of economical “green” energy is friendly to the environment, considerate of neighbors, and popular with utility customers. Faced with increasing federal and state regulation of manure, livestock farmers have become aware that a properly designed and operated waste management system which includes a biogas-to-energy power plant can not only control odor, but can also reduce overall operating costs. In regions where costs are high for electricity, heating fuels, or animal waste disposal, the production of electricity from biogas can provide substantial economic value to farmers. Energy savings plus profits are especially great where excess electric generation can be sold for profit to the utility. The total savings and payback can be impressive. For some farms, a modern, efficient, and easy to maintain biogas-to-energy system can help provide both EPA compliance for an acceptable manure management system and the added revenue needed to offset the costs of compliance.

A modern biogas-to-energy system fits seamlessly into livestock production and dairy operations.

The economical electricity generated by a biogas-to-energy system offsets all the utility power consumed by farm operations and other onsite facilities, and the thermal energy recovered from the microturbine engine can be used to maintain optimum digester temperature, to provide domestic hot water, and to heat barn space and floors.

In a typical biogas-to-energy system, manure is put into the digester where it is heated to accelerate anaerobic digestion. The biogas produced by decomposition (composed of about 55 to 70 percent methane) is captured and used as fuel to operate a generator. The energy produced is used to offset the cost of utility power and fuels for farm operations. Excess power can be sold for added profits.

The Ingersoll Rand microturbine system is a complete biogas-to-energy system ready for hookup and operation.

An Ingersoll Rand onsite energy system incorporates one or more rugged Ingersoll Rand microturbines, a matched fuel conditioner designed specifically for agricultural digester gas, and all necessary switchgear. Everything is completely configured at the factory for reliable operation and skid mounted for easy installation and hookup — with or without a connection to the grid. Farms that now flare digester gas — literally wasting a valuable energy resource — may be able to simply redirect the gas from flaring to fueling a microturbine. Although anaerobic digester gas is essentially a free or lowcost fuel for a microturbine, some pretreatment of the gas is required. The integrated Ingersoll Rand fuel conditioner is designed for a wide range of biogas conditions and effectively removes hydrogen sulfide (a highly corrosive and toxic gas) and other contaminants from the gas stream. The fuel-conditioner compressor also permits the microturbine to operate at sites with low available pressure.