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coal mining

In support of cleaner coal

While some young Kiwis are screaming ‘Armageddon’ at the mention of coal, private New Zealand company Mokau South Resources is hoping to develop one of the country’s largest remaining coal resources and says we need to get real about non-polluting coal technology, and the fact coal-power around the world is expected to increase. NEIL RITCHIE explains.

MOKAU SOUTH RESOURCES (MSR) director Murray Sampson says “clean coal” facilities and operations that capture and store carbon are already in use.
The businessman, based at Silverdale north of Auckland, says a commercial clean coal facility that opened in the United States earlier this year is a good example of using coal in innovative, non-polluting ways.
This was a collaborative project between US company NRG Energy and Japan’s Nippon Oil & Gas Exploration Corporation, which opened the first large scale clean coal facility in that country using carbon capture and storage (CCS) technology.
Their project, called Petra Nova, captures carbon dioxide (CO2) from the coal combustion process and pipes this from the plant, outside of Houston, to the nearby West Ranch commercial oil field where the CO2 is injected into the field, forcing additional oil out. Some of the CO2 remains in the field after the enhanced oil recovery process has finished.
The companies say their plant can capture more than 90 percent of the CO2 released from the equivalent of a 240-megawatt coal-fired power station, which translates into about 5000 tonnes of CO2 per day or more than one million tonnes per year. They call this “the world’s largest post-combustion carbon capture system”.
NRG Energy president and chief executive Mauricio Gutierrez says installing CCS technology in existing coal plants “will have a pretty significant application in current plants throughout the US and for that matter, throughout the world”.
Murray Sampson reckons a similar CCS power station using the nation’s good coal resources could be easily built in Taranaki to supply the necessary extra electricity needed for all the electric vehicles that are expected by the government to be on our roads in the next few years.
He also told Q&M that he and fellow MSR director, older brother Ian, have recently withdrawn the company’s Resource Management Act consent applications to the Waikato Regional District Council as they considered “most were unnecessary”.
He says the company will re-apply at a suitable time after a bit more study. Both brothers are distant descendants of the first Sampsons – Charles and Marie – to settle in Taranaki after arriving in New Plymouth during 1842 aboard the ship Timandra and who are buried in Te Henui Cemetery in New Plymouth.

Coal bins on the Pukemoi railway line before being railed to a waiting ship up the Mokau River. Courtesy of Mokau Museum.

The Mokau field contains some five coal seams, one up to three metres thick, and potentially holding up to 15 million tonnes of sub-bituminous coal able to be accessed by opencast mining. Sub-bituminous coal typically contains 35-45 percent carbon, compared to bituminous coal (45-86 percent carbon) and the rare anthracite coal (86-97 percent).
Murray Sampson says the company’s proposed opencast mining method will not be “a huge hole”. As the resource is extracted, the hole is filled and the land reinstated. Only small parcels, about 20 hectares, will be mined at a time, leaving most of the mining lease, which covers about 740 hectares, untouched for years.
“Some of this coal is still mineable at current prices, so it remains a good asset,” he adds.
Eleven mines operated in the Mokau coal field between 1884 and 1987 and the original Stockman mine employed two men and supplied the local dairy factory as late as 1952.
Backing up Murray’s views is a recent US Energy Information Administration report that claims worldwide electricity generation from coal will still increase from about eight trillion gigawatt-hours (GWh) to 10 trillion GWh in 2040, even though the share of coal in electricity production will reduce from about 40 percent to 29 percent. This is because electricity demand will still grow worldwide, especially in China and India, where coal’s share in electricity generation will not decline.
“Coal is a relatively cheap feedstock for power generation and also a strategic resource,” he says.
“That’s why we still have some dairy factories powered by coal and why Meridian Energy recently asked Genesis Energy to keep some of its coal-fired units at the Huntly power station on standby during periods of low hydro lake levels, particularly during dry winters in the South Island.
“So it’s short sighted to write off coal right now.” 

This article first appeared in Q&M‘s December- January issue.

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