Gas industry advocates argue that expansion of gas infrastructure is justified because it will be possible to switch to low-carbon gases such as hydrogen and biomethane in future. But research by the International Council on Clean Transportation (ICCT) predicts that biomethane production will remain modest, even with massive subsidies.
The idea that Europe’s gas sector could go carbon-free by 2050 is nothing more than a pipe dream, according to new research.
A study by environmental policy analysis group the International Council on Clean Transportation (ICCT) shows renewable methane, the most promising low-carbon natural gas substitute today, could offset at most 12% of total projected European gas demand in 2050.
“There has been a lot of attention on studies funded by the gas industry, claiming that the entire European gas supply could be decarbonised by renewable gas by 2050,” says Stephanie Searle, one of the report’s authors. “We found the potential for renewable gas was much, much more limited.”
The gas industry has put forward various estimates for the amount of renewable gas that could go into Europe’s energy system by 2050. Last year, Beate Raabe, the secretary general of Eurogas, the trade association representing the interests of the gas industry in Europe, gave a figure of 76%.
Gas Wind and Sun, a Eurogas website, says the level could be 70%, amounting to around 322 billion cubic metres (bcm).
“Most of the renewable gas potential would require subsidies or other policy incentives in the range of €1.50 to €4 per cubic metre”
A study in February by the Navigant consultancy Ecofys, funded by a gas industry consortium called Gas for Climate, came out with a more modest estimate of 122 bcm by 2050.
More than 80% of this gas would be in the form of renewable methane, said the study, which the remainder being renewably-produced hydrogen.
Biomethane is produced through anaerobic digestion, a mature technology, which is why it is seen as a frontrunner in the race to decarbonise gas.
However, the ICCT research, funded by the European Climate Foundation, a climate change mitigation group, casts doubt over previous biomethane estimates. It argues that at most 36 bcm of renewable methane could be produced by 2050:
Partly this is because the ICCT researchers take a dim view of some of the more optimistic assumptions of previous work.
For example, the ICCT team dismissed the potential of using renewable energy to create methane synthetically, or so-called power-to-methane, because in the short term it would involve high production costs and limited greenhouse gas reductions in Europe between now and 2030.
The ICCT also disagrees with Gas for Climate over the potential to use ‘cover crops’, or vegetation grown in alternate seasons to major crops, as a source of biomass for renewable methane.
“While there are some examples of successful cover cropping in Italy, across the EU it is seldom practiced,” notes the ICCT study. “Only around 3% of cropped area uses cover crops, and this rate is increasing slowly, if at all.”
Some other sources, such as wastewater sludge, are relatively easy to turn into biomethane and are already being used on a small scale, for instance for district heating. But perhaps the biggest challenge in growing biomethane production across Europe is its cost.
“We find that most of the renewable gas potential would require subsidies or other policy incentives in the range of €1.50 to €4 per cubic metre,” says Searle. “That’s 10 to 20 times the current average wholesale gas price.”
The high cost of biomethane production in Europe is a result of the continent’s agricultural economy. The greatest source of biomethane feedstock is from farms, but in Europe these tend to be much smaller than in America, for example.
“Looking forward, we can’t count on the gas supply becoming decarbonised”
A farm with, say, 50 cows does not offer great economies of scale for manure production, which makes it hard to build a biomethane business case.
And even if a group of farms could deliver enough manure to make it worthwhile to invest in an anaerobic digester, the cost of transporting the resulting biomethane to an injection point, or building out a gas pipeline, would be “prohibitive,” Searle says.
A more efficient option might be to burn the biomethane on site, to create electricity, the ICCT estimates. “It’s doable with policy incentives,” Searle says.
Whether policymakers would be keen to introduce expensive subsidies for biomethane, at a time when other renewable energy sources are moving away from subsidy schemes and towards auctions, is a debatable point.
But the ICCT study implies that, for gas at least, public money will be key to helping decarbonise the system. And even then, it won’t go far enough. “Looking forward, we can’t count on the gas supply becoming decarbonised,” says Searle. “We think it is not physically possible.”