The major New Zealand coalfields are located in the Waikato, the West Coast, Otago and Southland. An estimated 2.9 million tonnes of coal is mined for domestic use and for export, mainly from open cast mines.
Coal has played a key role in the development of modern New Zealand. At present there is no practical alternative to coal as a source of affordable, accessible, readily available industrial process heat for fuelling our industrial processes.
Alternative technologies are increasingly available, e.g. partial conversion to wood waste (biomass) and electrification, but for the immediate future major New Zealand food producers, including dairy, rely on coal as energy for their manufacturing facilities.
During Covid-19 coal mining was considered an essential service because of its use in food production and heating hospitals.
Coal’s annual economic contribution to the country runs into many billions of dollars, thinking of steel, cement and lime, food , as examples of goods produced using coal. If we didn’t have extensive domestic supplies, coal would be imported, and, at times it is, currently in significant quantities, 1.8 million tonnes in 2021 which is more than half of what was consumed locally.
Coal mining plays a substantial role in underpinning several regional economies, particularly on the West Coast of the South Island.
Today the coal industry is highly regulated, including in relation to CO2 emissions.
The coal industry has an interest in New Zealand’s energy future, and the types of pathway New Zealand could take in varying its energy mix. It is inevitable that the role of coal in the New Zealand economy will change over time.
Coal is highly variable in quality and also from one mining operation to another. For this reason, blending is an important part of the value chain for coal.
Some New Zealand coal has highly sought-after properties, such as low-sulphur and ash content, and superior “swelling” properties for use in blast furnaces. This coal is exported to steel makers in Japan, India, Korea, and Australia.
Types of coal depend on various factors including the plant matter it was formed from. As coal becomes compressed underground over time it gradually changes from peat, to lignite or brown coal, then to sub-bituminous and bituminous coal and, in some parts of the world, into the hard and shiny anthracite.
New Zealand’s main coals are: