Turning pig manure into an energy source
The agricultural and livestock industries have voracious appetites for energy, water and other precious resources. The concept of sustainability can and must be promoted, for example through measures to reduce dependence on fossil fuels. The LIFE QUALITY programme funded a unique project, PIG HEAT AND STRAW, aimed at recovering heat from pig manure on pig farms. The project was led by R&R Systems, a Dutch company with extensive experience in energy recovery systems. The new technology was implemented at two large pig farms, one in Poland and one in the Netherlands. The energy salvaged is used to heat the farm's energy-intensive installations, such as rooms where newborn pigs are raised as well as the farmer's residence. An added benefit of the system is that ammonia, methane and other noxious air emissions from the pig manure are significantly reduced, improving working conditions for farm staff. Data collected from the two test sites indicated that energy savings on the order of 50 Watts per meter squared could be achieved. This figure doubled when a solar roof was added to the building. The efficiency, and thus economic feasibility, of the system depends on maintaining a suitably thick layer of straw and manure, at least 40 centimetres thick. The results of the pilot study reveal that the new technology is best suited to sow farms and also sow and fattener farms. Yet, additional technical improvements could make it profitable in more applications. It should be noted that the climate benefits include not only reductions in fossil fuel consumption, but also decreased methane emissions. Methane is a strong greenhouse gas addressed by the Kyoto Protocol. R&R Systems has patented the technology. The market for this product is expected to grow as the percentage of pig farms using straw is anticipated to increase significantly over the next few years.