Construction has begun on what is thought to be Australia's first piggery to run electricity from an on-site biogas digester facility.

GD Pork was granted approval for a $14.5 million expansion to their Kojonup facility, 250 kilometres south-east of Perth, in August last year.

The expansion is expected to allow for site production to increase by double, to about 75,000 pigs a year.

But, the increase in production has led the company's managing director Torben Soerensen to look for new ways to supply the site with power.

"We're putting in an anaerobic digester tank, so basically a big tank where the waste from the pigs can go in," he said.

"The bacteria breaks it down [and] that creates methane which is then put into generators and it can create electricity that way."

The biogas facility is anticipated to enable the site to be fully self-sufficient.

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He said the biogas facility was capable of producing 1.7 megawatts per year, which was more than they needed on the farm.

However, he said what they did not use would be burned off as gas instead.

GD Pork managing director Torben Soerensen at his Kojonup piggery. ( ABC Rural: Tyne Logan )

Mr Soerensen, who is originally from Denmark, said the use of biogas facilities was big in other parts of the world, but had not yet been picked up in Australia.

"It's not a new technology; it's been used overseas for the last 20 years," he said.

"There have been similar systems [in Australia] where they do it in covered ponds, but this is the one where it's actually a digester itself."

He said it would be cost-viable for most West Australian piggeries.

"It will save us on electricity, but it also has some investment costs involved so at the end of the day, it's not good business; it's not why we do it," he said.

"Waste is obviously an issue with piggeries and if you don't do anything, you just stockpile your waste.

"It's a nuisance for neighbours and smells.

"By putting it through that process, you also eliminate the smell from the waste so that's a big plus.

"Then it just makes sense because otherwise, we would have to generate electricity from diesel, and if you look at it that way, then of course it's saving us money."

As a part of the expansion, a feed mill will also be built so GD Pork can buy feed grain direct from farmers.

The facility is expected to be operational by the end of the year.