New laws have stimulated Queensland’s green energy industry.

The Queensland Government's ethanol mandate has come into effect, meaning  E10 fuel now has to make up at least 30 per cent of all petrol available in the state.

United Petroleum’s grains-to-ethanol plant at Dalby in the state’s west – which turns locally grown sorghum and starch into ethanol – has been at capacity for some time, and hopes to expand based on the new rules.

Chief operating officer David Szymczak says the plant’s future is looking good.

“At this stage the plant is running at 100 per cent and we foresee that going forward,” he told the ABC.

“We did in previous years have to, from time to time, close the refinery for extended periods because the demand wasn't there.

“But with the uptake of E10 petrol and the boost to the economy, it's a win all round.”

Farmers say they like having the ethanol plant as a customer, as it buys grain year-round.

Recent expansions have allowed the plant to process up to 200,000 tonnes of grain this year.

The biorefinery also features a large dryer to convert the leftover grain into high-protein animal feed.

Mr Szymczak says the company has more growing to do.

“We'd have to build extra tanks on site to actually produce the ethanol,” he said.

“It would be a major project to do it but the plant was designed to be increased so that can be done.

“At this stage we haven't really committed to that expansion and we need to see what further signals there are from government about the expansion of renewable fuels.”