China carbon pledge throws spotlight on hydrogen fuel

Beijing's promise that its emissions will peak ‘before 2030' relies on transport sector CO2 reductions, writes Karen Teo

Curbing China's transport-sector CO2 emissions will be central to meeting President Xi Jinping's UN pledge that the country's emissions will peak "before 2030".

Using hydrogen as a road fuel would reduce emissions, but rolling out hydrogen fuel cell technology looks challenging. China's transport sector produces nearly 1bn t/yr of CO2, according to estimates by Tsinghua University's Institute of Climate Change and Sustainable Development. Hydrogen fuel is considerably more energy efficient than gasoline. A 5kg fuel cell allows a car to travel 500km — equivalent to 45 litres (11.8USG) of gasoline — with water as the only tailpipe emission.

Beijing has incorporated hydrogen fuel cell technology into its national fuel strategy, but development of the nascent sector — which would reduce China's reliance on energy imports and fight climate change — faces many challenges.

China has implemented new policies this year to boost hydrogen development, such as rewarding innovations. Government subsidies have already helped the country take major strides towards developing a hydrogen fuel cell electric vehicle (FCEV) fleet. The country had around 6,165 FCEVs at the end of last year, surpassing its 5,000 target for 2020. And Beijing aims to increase the number of FCEVs on the country's roads to 50,000 by 2025 and 1mn by 2030.

State-run oil giants PetroChina and Sinopec have committed to investing in hydrogen as part of a strategy to lower emissions by 2050. China's hydrogen FCEV plan also calls for the construction of 100 hydrogen refuelling stations by 2020, 350 by 2025 and 1,000 by 2030. Refuelling FCEVs is far quicker than recharging electric vehicles, but the cost of building hydrogen refuelling stations can be at least five times as much as for conventional ones. Just 80 have been built so far.

Sinopec, which produces 14pc of China's hydrogen, built four combined oil-hydrogen refuelling stations last year. The firm is building another 20 in Guangdong province and working with a local partner on four in Hebei, scheduled to open next year. It started work on an integrated retail station in Dalian last month that will provide conventional fuel as well as electric charging and hydrogen.

Capability brown

China is the world's largest producer of hydrogen. The country produced more than 21mn t last year, out of 70mn t produced globally. But most of China's hydrogen is "brown" — produced from fossil fuels, with coal accounting for 62pc of feedstock compared with 18pc globally (see table). Only 4pc of China's hydrogen is "green", using renewable-based electricity to convert water into oxygen and hydrogen by electrolysis. Coal remains the cheapest source of hydrogen but is also the most polluting.

China could use carbon capture and storage (CCS) to absorb the carbon from coal, allowing it to produce "blue hydrogen", but the technology is costly and the country has few operational CCS sites. The hydrogen Sinopec produces comes from refineries rather than renewables and is moved to retail stations through the its own pipeline network, limiting the geographic scope of its refuelling network.

Increasing renewable energy generation capacity will be crucial to meeting China's 2060 carbon neutrality pledge and producing additional hydrogen. China added 60GW of renewables capacity last year, but on-grid power prices must fall to 0.25 yuan/kWh (4¢/kWh) to compete with gas in hydrogen production and to Yn0.15/kWh to compete with coal. On-grid hydropower prices averaged Yn0.26/kWh last year, the cheapest among clean energy sources, making it the best candidate for producing hydrogen.

China must also find an economical way of transporting hydrogen to consumers — for example, by converting it into ammonia.