NZS 5442 (Int):2024: standard opens New Zealand's gas grid to biomethane

Standards New Zealand made available at the end of April 2024 the interim version of the standard NZS 5442 (Int):2024 – the specification for gas in the gas grid, which for the first time formally allows biomethane to be introduced into the existing system. The standard replaces the 2008 edition and covers methane gases from various sources: from natural deposits, from landfill degassing, biogas and coal seam methane drainage.

What changed

The most important technical changes are the relaxation of the oxygen content limit for biomethane and the lowering of the water limit in table 2. The first change makes it easier for biogas upgrading plants to meet the requirements, in which trace amounts of oxygen may appear in the product. The second is meant to protect the infrastructure against corrosion and hydrate formation.

Why the standard was a barrier

Before the change, the standard did not provide for renewable gases, so grid operators had no legal basis to accept them. Firstgas worked with Ecogas on a project to inject biomethane from food waste in Reporoa. The first injection was planned for 2024, and the standard was a formal condition.

Scope and requirements

According to Standards New Zealand, the new appendix A (informative) describes possible sources of biomethane and potential contaminants, and appendix B (normative) concerns processed biomethane; test methods and measurement frequencies were also updated. Appendix G was reserved for the future integration of hydrogen.

The future

The interim edition is the first step towards a full revision of the standard. This staged way of amending made it possible to open the grid to biomethane without waiting for the whole revision to be completed.

What this means for Poland

In Poland biomethane injection is based on national requirements for gas in the grid and on connection rules. The New Zealand case shows that updating the gas quality standard can be the first step towards opening the market, faster than changes to energy law. For upgrading designers the details matter: oxygen, water and contaminants, which determine the choice of cleaning technology.

Significance for designers

For biomethane producers the standard means a concrete list of parameters to be met before the injection point: composition, contaminant content, pressure and water dew point. It is also the basis for connection agreements with Firstgas. Without such a standard, every project would have to negotiate exemptions individually, which would lengthen preparation time and increase costs.