It's great for agricultural crops and a bit on the nose, but it's not your standard manure.

About 180,000 tonnes of biosolids are generated from Sydney's sewage each year, but authorities are having no troubles with getting rid of it.

Biosolids, which is a by-product of the sewerage treatment process, is proving a hit with New South Wales farmers who want to improve soil health and boost yields.

Harvested from 23 of Sydney's sewerage plants, the waste is processed through reactors which also create renewable energy that is fed back into the system.

These biosolids are bound for farms in regional NSW. ( ABC News: Uma Patel )

It is then trucked out to about 20 farms in the state's central west, as well as several mine rehabilitation sites.

Stuart Kelly swapped synthetic fertilisers for human biosolids on his family property at Newbridge, near Blayney five years ago.

He said his soil was healthier than ever and the farm was booming.

"My thing is healthy soils and healthy pastures is going to come back to healthy stock," Mr Kelly said.

"If you get healthier stock, more lambs on the ground, more calves growing quicker, we're in front."

Mr Kelly said while he still got raised eyebrows for using the sewage, it was helping complete the production cycle between city and bush.

Soil 'just keeps responding'

Agronomist Roger Crisp said the use of biosolids across central west farms was paying massive dividends, with stock capacity and output more than doubling for many producers.

Farmers have battled dry conditions and frosts this winter, sheep farmer Gordon Nash, biosolids have offered significant protection.

Agronomist Roger Crisp (L) and farmer Stuart Kelly (R) say using biosolids makes sense. ( ABC News: Luke Wong )

His land at Wattle Flat near Bathurst was once "just like gravel", but now he said biosolids had significantly improved moisture retention in the soil.

"It just keeps responding, you might get 5mm of rain and it just starts producing, whereas untreated pastures, they're just getting hammered with frosts and not doing anything," Mr Nash said.

The NSW Minister for Energy and Utilities Don Harwin said not only was it helping the environment, but also helping to improve efficiency for Sydney customers by reducing energy costs.

Sydney Water spokesman Gavin Landers stressed using human waste on crops was safe, with no issues reported in the past two decades.

"Ironically, the production and application of biosolids is more highly regulated than any application of other fertilisers, so there's a lot of protections in there to ensure we don't any problems," Mr Landers.