First Gas invests millions to use biogas, but delays green hydrogen trial

Wednesday, 8 December 2021

Biogas from organic waste could meet all the gas needs of consumers and the restaurant trade, First Gas says, though ‘green hydrogen’ would be needed to wean industrial users off natural gas.

First Gas has committed to supply thousands of homes and businesses with biogas produced from organic waste but has had to delay a more ambitious ‘green’ hydrogen trial originally slated for this year.

First Gas commercial manager Ben Gerritsen said the company would spend about $6 million to $8m connecting its gas distribution network to a biogas plant that specialist firm Ecogas expects to finish building near Broadlands in the central North Island by about the middle of next year.

The investment would enable First Gas to clean, compress and supply enough biogas to meet the needs of 9000 homes and businesses, First Gas said.

The biogas will be generated from organic waste – including food scraps and agricultural and landfill waste – that would otherwise break down naturally and more slowly release methane directly into the atmosphere.

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First Gas said it would displace natural gas that would otherwise result in 11,000 tonnes of carbon emissions annually.

Gerritsen said First Gas expected it to be the first of many similar schemes.

A study by engineering firm Beca, First Gas and Fonterra estimated in July that biogas produced from waste sources could replace up to a fifth of the natural gas the country currently uses by 2050.

Biogas plants, like this one in Spain, have the advantage that the gas they produce is methane, which can be used by existing appliances.

Gerritisen said that would be enough to meet the needs of all residential gas consumers as well as the cafe and restaurant trade.

But First Gas, which is the country’s largest gas distributor, is counting on a switch to “green hydrogen” produced using renewable electricity and water to meet the future needs of its industrial customers and fully end its reliance on natural gas.

In March, it sought to reassure customers that gas had a long term future by announcing it intended to conduct a small scale trial this year that would involve it mixing 1 per cent hydrogen into one of its networks.

It said then that would be a precursor to it stopping piping natural gas to customers and switching to hydrogen between 2035 and 2050.

That ambitious road map would mean more than 60,000 North Island households connected via its 7000 kilometres of gas pipes would need to replace their gas appliances during that period.

Gerritsen said the initial hydrogen trial was being progressed but had been pushed back to the middle of next year.

“One of the key steps is to get an exemption from WorkSafe to conduct the trial and it has taken us longer to pull together the information for that exemption request,” he said.

“Then it will take some months for WorkSafe to look through that and consider it.”

Gas users should not be concerned that the schedule for converting to green hydrogen had slipped at an early stage, he said.

“The delays we have experienced so far don’t really have an impact on the longer term roll-out,” he said.

“That is not to say there aren’t some challenges in the subsequent phases of rolling out hydrogen and making it a big part of New Zealand’s energy mix.”

First Gas chief executive Paul Goodeve said in a statement that the separate biogas project was “groundbreaking”.

“Biomethane is chemically identical to natural gas so there is no need to modify pipeline

infrastructure or gas appliances,” he said.

Ecogas general manager Alzbeta Bouskova said it was a great example of “a low carbon

circular economy in action”.

The organic waste will be broken down using bacteria to speed up the release of methane.

“Anaerobic digestion is the most environmentally responsible way to recycle organic waste and works in tandem with cities facing waste challenges and companies trying to reduce their emissions,” Bouskova said.

“Injecting this renewable gas into the pipeline is proven technology overseas and we are excited to be part of bringing it to New Zealand.”