On the path to net zero, global gas demand will continue rising until the middle of this decade, the International Energy Agency forecasts. Especially in developing countries and those depending on the resource for economic growth the fossil fuel will continue to play an important role. How can we ensure that its use emits as little CO2 as possible and does not stand in the way of reaching the Paris Agreement target?

Margriet Kuijper, an energy consultant and former manager at oil giant Shell, is a proponent of the Carbon Takeback Obligation (CTBO), a concept first coined by University of Oxford professor Myles Allen. She told Climate Transformed in an exclusive interview that it is the production of natural gas, rather than oil or coal, that needs to be targeted and held accountable for its carbon emissions because of the fuel’s continued importance in the future energy mix.

“If we don’t manage to move to renewables as quickly as possible then our fallback option is fossil gas, that’s what it comes down to. That’s why we think it’s worth investing in using that fossil gas in a different way,” Kuijper told Climate Transformed.

Under the CTBO concept producers of fossil fuels will be obliged to capture and permanently store CO2 directly emitted by their products. While currently less than 0.1% of carbon is stored, the CTBO proponents’ target is to raise this figure to 10% by 2030, to 40% by 2040 and to permanent storage of all carbon emitted by 2050.

“Net zero basically means that if you want to put a molecule of greenhouse gas (GHG) into the atmosphere you also have to take one out of the atmosphere and you have to show and demonstrate that,” Kuijper explained. “More strongly put, under the CTBO you can only take carbon out of the ground if you hand in a certificate that shows carbon has been stored.”

CCS (carbon capture and storage) technology has been included in many governments’ net zero strategies, including in France, the UK and the Netherlands. Spurred by the political support, CCS projects are growing rapidly. This year alone, global carbon storage capacity has risen by 52% to 111 million tonnes a year, according to an October report from the Global CCS Institute.

An implemented CTBO scheme would throw significant weight behind CCS projects, which Kuijper said could act as commercial storage sites for those in need of transporting and storing carbon under the CTBO scheme.

CTBO backers are in talks with governments bordering the North Sea to promote the idea of a North Sea agreement on joint CCS projects linked to a CTBO scheme. “It would be useful to sell carbon across borders to where they can be stored most efficiently. We’re hoping to develop that sense of community and once you have it in the North Sea region other countries could then join in trading the storage capacity,” Kuijper said.

A traded market for carbon storage certificates is the natural outcome of a CTBO scheme. Much along the lines of existing carbon trading schemes, it would see fossil fuel producers purchase carbon storage certificates which are subsequently retired.

“Once the countries agree on the stored fraction — or the percentage of stored carbon — it’s a fairly simple system to run with. Here we only need two numbers, one [reflecting] what comes out of the ground and [a second one reflecting] what goes into the ground,” Kuijper said.