By Philip Gruber, Lancaster Farming.
Small-scale methane digesters could help more dairy farmers take advantage of a technology that so far has mostly been available to the largest farms.
As with large digesters, making each unit cost-effective is the top challenge for small digesters, said Stephanie Lansing, a University of Maryland ecological engineering professor.
The waste-to-energy digesters use microbes to break down manure. The methane produced can be converted to electricity.