Mayor's Message: Landfill gas deal practical climate action

Council has finalised a three-year contract with Health NZ to sell the methane gas from the York Valley Landfill to heat Nelson Hospital. This is a good deal for the environment, ratepayers and the hospital.

Climate change is caused by increased concentration of gases such as carbon dioxide, methane and nitrous oxide that warm the atmosphere. Methane is only 18% of the problem globally but for NZ it is 48%. Most of NZ’s methane comes from farm animals but 9% comes from landfills, from the decomposition of organic waste. Nelson’s biggest source of methane, as we don’t have a large farming area, was the York Valley Landfill at 44,000 tonnes per year in 2020/21.

It was costing more than $2 million a year under the Government’s Emissions Trading Scheme for the methane emissions from the landfill. A 2022/23 investment in more than 40 wells and a network of pipes to collect this gas and flare it, eliminated this cost. The reduction in GHG emissions by 40,000 tonnes a year is huge – by comparison the new eBus service has reduced emissions by 1,700 tonnes a year. The benefit of the new contract with Health NZ is that the gas is to be sold to the hospital and used for its heating, earning more than $600,000 per year from next year.

The deal also makes sense for the hospital. It has been using coal for heating for more than 50 years. Coal is the least-efficient fuel with the highest greenhouse gases. It also produces fine particulate pollution that causes smog and is associated with cardiovascular disease. The area around the hospital is our most vulnerable to smog because of the valley’s typography and was one of NZ’s most polluted airsheds.

We have done a fantastic job as a city over the past 25 years in cleaning up the air quality in this area by changing our home heating from burners to heat pumps and reducing pollution from vehicles with tighter fuel standards and cleaner exhaust systems. It was an anomaly for the hospital to still be burning coal. This deal enabled the old coal boiler smokestack to be demolished this winter.

This three-year contract is an interim deal until 2029. There is a longer-term discussion to be had with Health NZ on how best to heat the redeveloped hospital. Council also needs to think through, given that the hospital does not use all the landfill gas, what to do with the remainder.