An ecological solution to climate change is not happening – and that’s a good thing

You’ve probably seen those nice graphs showing carbon dioxide levels and temperatures falling towards the end of the century. How is this miracle to be achieved? The idea is that we harvest the plants, burn them for energy, and then capture and store the CO2. Voila, problem solved!

Except bioenergy with carbon capture and storage, or BECCS, as the idea is known, is proving to be an unmitigated disaster. It is not being implemented on the scale required, partly because it is ridiculously expensive, it would be disastrous for biodiversity if done on that scale, and last but not least, it doesn’t even work. It actually increases CO2 emissions rather than reducing them at the times that matter.

As CarbonBrief’s Leo Hickman documentedBECCS was first proposed in 2001 by Swedish researchers who were thinking about how the country’s paper mills could obtain carbon credits. In 2005, several climate modelers seized on this entirely theoretical idea as a way to justify scenarios in which global temperatures, after exceeding 1.5°C, would drop again. In 2014, the fifth report of the Intergovernmental Panel on Climate Change (IPCC) highlighted climate models that predicted that huge amounts of carbon could be removed by BECCS. A non-existent technology somehow became the “official solution” to save the world.

For a while it looked like it might become a reality. In 2015, energy company Drax in the UK announced that a huge coal-fired power plant would be converted to wood pellets and CO2 would be captured and stored.

Ten years later, the Drax factory burns wood pellets but captures no carbon. actually like Political reported earlier this monththe company has now shelved its plans to do so. So the world’s flagship carbon capture and storage bioenergy project is now dead—or at least in intensive care. “We still see BECCS as a potential option for the site, but it’s much longer term than we originally planned,” says a Drax spokesperson.

Several other smaller projects are planned around the world, but it is clear that BECCS is not developing as it was predicted ten years ago. And there is a reason for this – governments are getting rid of the necessary massive subsidies. “It’s phenomenally expensive,” he says Tim Searchinger at Princeton University.

It might seem like a bad thing that we’re not introducing technology to save us, but it’s actually a good thing because it’s not working—at least not in the time frame we need. “There are probably unrealistic scenarios where you might get some negative emissions. But they’re not that big and you don’t get any benefit for decades,” says Searchinger.

To help convince policymakers, he and his colleagues they release a computer model of the relevant carbon fluxesso people can play with the numbers themselves. This model suggests that it could take 150 years for BECCS to remove any CO2 from the atmosphere, and that the first few decades are worse than burning natural gas without any carbon capture. And it will triple the cost of electricity.

Why? BECCS essentially converts CO2 already stored in forests into CO2 that can be stored in other ways—like in geological structures underground—but a lot of that CO2 is lost in the process and ends up in the atmosphere.

For starters, a lot of forest carbon never reaches the power plants—roots rot, other vegetation is destroyed by logging, and so on. All of this carbon ends up in the atmosphere.

Burning wood also produces twice as much carbon per unit of energy as burning gas, while lower temperatures mean less energy can be converted into electricity. Carbon capture is also energy intensive. So power plants would have to burn a lot of extra wood just to power the carbon capture process – which is likely to capture only about 85 percent of the CO2 released.

There is another, more subtle problem. Some argue that it is okay to use wood for purposes such as BECCS as long as the carbon is not removed faster than the forest takes it in. However, climate projections predict that many forests will absorb additional carbon due to the fertilizing effects of CO2 – or, in the jargon, that soil subsidence will continue to increase. So what some see as sustainable harvesting is actually destroying the climate solutions we already rely on.

These arguments apply to slow-growing trees, and many BECCS scenarios assumed the use of fast-growing energy crops such as grasses. This might bring modest benefits if we had lots of vacant farmland sitting around doing nothing, but the global picture is that we are still cutting down rainforests to clear more land for farms to grow food. Clearing much more land would be even more catastrophic for biodiversity.

Without BECCS, it might be unclear how we will reduce CO2 levels, but now we should focus on preventing them from increasing further. “We should accelerate our transition to wind and solar as much as possible,” says Searchinger.

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