The Nova Scotia Federation of Agriculture wants sewage sludge used to power farms, instead of fertilizing them.

The practice of spreading sewage sludge on farm land has been controversial in the province. The federation is now discouraging farmers from using the waste.

The group says the Halifax Regional Municipality will have seven million tonnes a year of biosolids. So it's suggesting the material be mixed for another purpose.

"One of the things we want to do is look at how that could be integrated with agricultural waste to produce biogas," said Lawrence Nason, executive director of the federation.

Biogas is an alternative energy source that is used in Europe and the United States. After the waste is heated it creates water and methane.

At the end of the process there is still some material left over that would have to be composted. But the federation says this is a more acceptable practice than spreading sewage sludge on fields.

Federation officials will discuss the idea at a meeting with the ministers of environment and agriculture later this month.

A community in southwestern Ontario plans to be the first manure-powered municipality in Canada. A plant will be built north of London to convert biogas from manure into electricity.