REGIONALREPORT TriadCompanies are high on the hog Beginning this
year, state law mandates that public utilities generate a
portion of their power with swine and poultry waste, which can
be converted to methane that fuels turbines. At the same time,
companies are looking for ways to reduce their greenhouse-gas
emissions, which lead to global warming. Cavanaugh & Associates
PA, a Winston-Salem engineering firm, believes it has developed
an answer to both problems. In 2006 — as the General Assembly
was mulling over a bill, which it passed a year later, that
would require utilities to use renewable energy — Duke
University’s Nicholas School of the Environment asked Cavanaugh
to design a swine-waste system that would generate electricity
while protecting the environment. Construction began in 2010 at
Loyd Ray Farms, a 9,000-hog operation on about 150 acres near
Yadkinville, and was completed last May. The system collects
about 80,000 gallons of waste a day in an oxygen-free digester.
Bacteria convert organic mater