Turning Agricultural Residues and Manure into Bioenergy (2014)

July 2014
Leftover crop materials and manure can help provide clean energy—but it’ll take the right policies, practices, and investments.

While most crops are valued for their harvests, leftovers like stalks and cobs are important resources too.

Known as “crop residues,” these resources help protect soil from erosion and loss of soil carbon. They can also be turned into ethanol for fuel or used for electricity.

UCS analysis finds that by 2030, U.S. farmers could sustainably produce up to 155 million tons of crop residues, many times the current level of production. U.S. livestock could produce another 60 million tons of manure, to be turned into clean-burning biogas.

The right policies, practices, and investments will help these clean energy sources realize their potential—with huge benefits for farmers, communities, and the environment.

Agricultural biomass can provide clean energy and local benefits

Under the right circumstances, crop residues and manure offer significant economic and environmental benefits.

For example, extracting biogas from manure can improve water quality, reduce methane emissions, and return nutrients to the soil, especially at smaller scale facilities.

Fuel and electricity made from agricultural biomass is potentially clean too. With the right practices, ethanol made from crop residues can produce 90 percent fewer lifecycle emissions, compared to gasoline.

The opportunities are diverse and widespread

Many states could significantly scale up their use of crop residues and manure. The largest include Iowa, a leading producer of corn ethanol, and Arkansas, the nation’s top rice producer.

Other potential leaders include California, where progressive climate policies exist alongside significant agricultural output, and Texas, one of the nation’s largest agricultural states and home to a sizable cattle industry.

These and other states have the foundations in place to make widespread agriculture-based energy a reality—but we need the right leadership and investment.