Carbon capture an option for Huntly power station owner Genesis?
The countrys largest generator of coal and gas-fired electricity, Genesis Energy, is hoping there may be a new way to reduce its environmental impact. Genesis chief operations officer Rebecca Larking said the state-owned power generator had this year begun a partnership with another organisation in their exploration of carbon capture. Larking was tight-lipped about what the partnership involved, saying Genesis couldnt say more at this stage. The biggest carbon-capture opportunity in front the company would be to trap emissions from its coal and gas-fired Huntly power station. READ MORE: * 'We have enough gas to support NZ through to a fully renewable system', ministry clarifies * The real deal on NZ Steel: Climate change win or corporate welfare? * Huntly burns wood instead of coal during short trial * Budget's carbon savings equal about five days coal use at Huntly But there is also speculation that the company could offer to capture emissions if it invested in a new gas-fired power station designed to help meet rising peak electricity demand. It is understood that carbon capture and sequestration has recently attracted strong interest from the Government as it seeks alternative ways to meet the countrys international commitments on emissions reductions. Huntly is the countrys largest power station , with a capacity of 953 megawatts. While its emissions can vary greatly each year depending on the demand for thermal power, in the year to June 2021 it was responsible for almost 4% of the countrys carbon emissions. NZ Steel said it had also investigated and was continuing to monitor opportunities for carbon capture. Its Glenbrook steel mill has been a major source of carbon emissions, though those will reduce as it switches its emphasis from smelting iron ore to recycling steel . A spokesperson said the technologies it had looked at to date had been too limited and expensive, so hard to make work at the scale we need. We would note over the past 10 years they have noticeably improved efficiency and lowered cost, so we will keep a watching brief and are open to future opportunities, she said. The International Energy Authority has reported there are 40 commercial facilities around the world currently capturing emissions from industrial processes, fuel transformation and power generation, with a combined capacity to sequestrate 45 million tonnes of carbon emissions a year. For comparison, New Zealands annual emissions are about 75 million tonnes. There are two common ways to prevent carbon emissions from entering the atmosphere and Genesis would not comment on which one its partner was exploring. New Zealand-founded and Nasdaq-listed technology company LanzaTech has commercialised a technology that involves feeding concentrated streams of carbon-dioxide rich gasses from the likes of steel mills to bacteria in bioreactors. These can convert the waste gasses into ethanol for re-use as jet fuel or plastic, in an example of the circular economy. Another technique is to capture carbon dioxide and then attempt to store it permanently, for example by pumping the gas into underground cavities such as decommissioned oil and gas wells or saline aquifers. The latter technique can be most suited to sequestrate carbon dioxide that is released alongside natural gas from oil and gas fields. Carbon dioxide has commonly been injected into working wells for the commercial purpose of squeezing out more oil and gas. Some carbon dioxide is currently captured from Todd Energys Kapuni gas field in Taranaki, but rather than being permanently sequestrated, it is then bottled for use in the food and drinks industry . The gas extracted from the Kapuni field has an unusually high concentration of more than 40% carbon dioxide. Energy Resources Aotearoa, whose members include businesses involved in the oil and gas sector, including Genesis Energy, and which wants to reverse the current ban on new offshore exploration permits , has been talking up the potential for carbon capture and sequestration. Chief executive John Carnegie noted that British chancellor Jeremy Hunt said in March that he envisaged Britain investing about 20b (NZ$41b) in carbon capture and sequestration over the next 20 years. However, any suggestion that carbon sequestration could allow countries to take the foot off the gas reducing gross emissions has faced strong pushback from some climate-change experts. The Intergovernmental Panel on Climate Change has cautioned that the storage of carbon dioxide underground is not necessarily permanent. Oil and gas wells can gradually flood or be damaged by seismic activity and leak gas. Illustrating those risks, Contact Energy has used an old gas field at Ahuroa in Taranaki to store natural gas, but had to write down the value of that facility by $86m this year after it discovered water was seeping into the site , reducing its storage capacity. Carnegie did not believe New Zealand needed to subsidise the use of carbon capture technologies. That is because we already have a comprehensive emissions trading scheme that would incentivise firms to capture and store carbon to reduce their emissions, he said. The only assistance required will be a supportive regulatory regime that allows carbon to be sequestered in reservoirs. Cost appears to remain an obstacle at current carbon prices, unless waste gasses can instead be bioengineered into saleable products such as ethanol, however. The International Energy Authority has cited research conducted in 2018 that suggested the cost of capturing carbon dioxide from power stations was then in the range of US$56 to $64 (NZ$93 to $107 a tonne). That is more than the $65.25 price that New Zealand polluters needed to pay on Thursday for a carbon credit giving them the right to instead emit the same volume of carbon dioxide into the atmosphere.