Global oil and gas giants Shell and ExxonMobil have teamed up with China National Offshore Oil Corp and the Guangdong provincial government to conduct a feasibility study to build China’s first large-scale offshore carbon capture and storage (CCS) facility in Shenzhen. The proposed capacity of the project in Daya Bay off the coast of the southern Chinese city is 10 million tonnes a year, making it one of the largest mooted globally so far. The buildout of CCS projects globally will require US$655 billion to US$1.28 trillion of investments, Global CCS Institute estimated in a report last year. While the partners did not provide the investment outlay for the project, a similar CCS project with a capacity of 10 million tonnes a year proposed by Australian oil and gas producer Santos, 500km offshore from Darwin, is estimated to cost US$1.6 billion, according Sanford Bernstein senior analyst Neil Beveridge. China’s carbon dioxide emissions, the biggest pollutant known to cause global warming, amounted to 9.9 billion tonnes in 2020, 30 per cent of the global total, according to BP. “If successful, it will be China’s first offshore large-scale carbon capture and storage hub, which could help … serve the decarbonisation needs of enterprises in the [Daya Bay National Economic and Technological Development Zone],” Shell said in a statement on Tuesday. The project could serve as a model for the chemical industry seeking to decarbonise, and support China’s goal to become carbon neutral by 2060, ExxonMobil said in a separate statement. For the world to achieve the Paris Agreement’s net zero emission ambition by 2050 to avert disastrous climate change consequences, CO2 captured annually needs to rise from 40 million tonnes currently to 1.6 billion tonnes in 2030 and 7.6 billion tonnes in 2050, according to the International Energy Agency. Some 95 per cent of the captured gas will need to be stored in permanent underground caverns, with the rest used to make synthetic fuels. The annual capacity of CCS projects under development globally has risen 48 per cent to 111 million tonnes last September from December 2020, according to the Global CCS Institute. Most are in the US and northern Europe. Shell and state-owned China National Offshore Oil have a US$4.1 billion 50:50 joint venture petrochemical complex, which came on stream in 2006 in the Daya Bay petrochemical park. The zone houses many other petrochemical plants. Chemicals production is energy intensive. Through by-products and fuel burning, it contributes around 2 per cent of global greenhouse gas emissions. Shell’s greenhouse gas emissions from its global chemicals plants amounted to 11 million tonnes. Less than 3 per cent of its total emissions were from its China projects. China National Offshore, which makes fuel and petrochemicals besides extracting oil and gas, did not disclose its carbon footprint in last year’s sustainability report. Its listed subsidiary, CNOOC , an oil and gas producer, emitted 10.3 million tonnes of CO2 last year, and has targeted to cut more than 1.5 million tonnes of emissions between 2021 and 2025. Last September, CNOOC commissioned the nation’s first offshore CCS project with a capacity to put away 1.46 million tonnes permanently over five years. It involves reinjecting underground the CO2 that is extracted with crude oil, in oil wells some 190 kilometres southeast of Hong Kong in the South China Sea. ExxonMobil said it has cumulatively captured more man-made CO2 than any other company. It has an annual carbon capture capacity of 9 million tonnes and has stakes in about one-fifth of the world’s CCS capacity. “This is one of the largest CCS projects worldwide and is a great demonstration project,” said Beveridge of the latest CCS project in China. “For coastal China, the availability of depleted offshore oil and gas fields to inject the gas into is absolutely critical.”