Boris Johnson’s chief adviser Dominic Cummings is backing a scheme to suck carbon dioxide out of the air using technology first used on World War Two submarines.
The PM's advisor wants to spend £100 million on 'direct air capture' (DAC) machines, which consist of a stack of metal 'air scrubbers' that use a chemical solution to remove the CO2 from the atmosphere.
The CO2-laden solution is then stored underground, reducing the amount of the greenhouse gas that reaches the atmosphere.
The gas can be permanently stored in deep geological formations, or used to make fuels, chemicals, building materials and other products.
The tech could help to offset emissions from energy-intensive sectors that are difficult to decarbonise, such as transport and aviation.
And because the CO2 is being permanently removed from the atmosphere, the technology supports the UK's net zero emissions target for 2050.
However, a roll out of the technology would be expensive and demand massive amounts of energy - which in itself could be a huge source of CO2 emissions.
Experts have warned that these machines could use 'a quarter of global energy supplies' by 2100.
Critics of the technology say it is an 'expensive and energy-inefficient distraction' for meeting the hard choices necessary to meet the target, according to the Times.
To capture enough carbon to offset emissions from the aviation sector, the technology would require additional electricity equivalent to building up to five new nuclear power stations.
According to academic research, the technology is incredibly expensive and requires tremendous energy. For each ton of CO2 captured, it costs around £500, the Times says.
DAC has also been seen to encourage continued use of carbon-belching fossil fuels rather than switching to renewable sources of energy.
The technology also has safety concerns – after being stored underground, CO2 could leak and taint nearby water supplies or create tremors caused by the build-up of pressure underground.
Despite this, Cummings has authorised £100 million from the Treasury to further develop the technology, to enable Britain to reach its climate change obligations.
‘Dom had become obsessed by this,' one Whitehall source claimed.
'He’s the one who has been pushing it despite huge scepticism from officials. But he’s got his way.’
MailOnline has approached Number 10 for a comment.
A Dublin-based DAC company told MailOnline that the UK government would be well-advised to single out direct air capture for investment and estimated a cost of £100 per ton of carbon capture.
'Without technology to dispose of the excess emissions left in the air from two centuries of industry, efforts towards future decarbonisation will be meaningless,' said Pól Ó Móráin, CEO of Silicon Kingdom Holdings Limited.
'Assertions that direct air capture will always be energy intensive and therefore uneconomical are outdated.'
Direct air capture technology was used 80 years ago, during the Second World War, to maintain breathable air in submarines.
Scaled up for the modern day, it would exist as sci-fi-esque grids made up of the individual, stackable filters known as 'collectors'.
Surrounding air is drawn into each collector with a powerful fan and CO2 is captured on the surface of a filter material, usually either a chemical or a solid membrane, that sits inside the collectors.
When the the filter material is full with CO2, the collector is closed and the temperatures inside are increased to up to 212°F (100°C), which releases the CO2 from the filter and captures it for storage.
The extracted CO2 is then put to good use for a variety of applications, such as manufacturing plastics, boosting plant yields in agriculture or in the food industry to carbonate beverages.
There are many options to store CO2 permanently after it has been captured from the air, according to Zurich-based DAC company Climeworks, such as underground mineralisation.
The more grids that are positioned around the country, the more carbon is captured.
These grids would be best placed in areas where carbon emissions are high, such as aviation hotspots or urban centres with high traffic densities.
There are currently 15 DAC plants operating worldwide, according to the International Energy Agency, capturing around 9,000 imperial tons of CO2 per year.
The US is is a leader in the field and currently has a capture plant that sucks around 9.8 million tons a year in advanced development, although the tech also exists as part of an EU-backed project in Hellisheidi, Iceland.
Zurich-based Climeworks commissioned the opening of the the world's first commercial-scale DAC plant in its home country of Switzerland back in 2017, based on working prototypes from labs at research university ETH Zurich.
By bringing the technology to the UK, Cummings believes that, with a significant early investment, the country can become a world leader in the area.
Last year, the UK became the first major economy in the world to pass laws pledging to end its contribution to global warming by 2050.
The target will require the UK to bring all greenhouse gas emissions to net zero by the middle of the century, by which time 10 billion tons of CO2 will need to be removed from the air every year.
Net zero means emissions would be balanced by schemes to offset an equivalent amount of greenhouse gases from the atmosphere, such as planting trees or using carbon capture.
But in a research paper last year, climate scientists warned that global carbon capture technology could use as much as a quarter of global energy supplies in 2100.
Policymakers should not see the tech as a 'panacea' that can replace immediate efforts to cut emissions, one of the study authors told climate website Carbon Brief.
The energy needed to run DAC machines in 2100 is up to 300 exajoules each year, according to the paper – more than 200 times the energy of the 2011 Tōhoku earthquake and tsunami in Japan.
300 exajoules is more than half of overall global energy demand today and would be a quarter of expected demand in 2100.
Dr David Keith, chief scientist at Carbon Engineering, a Canadian-based clean energy company, has previously said DAC will make sense to reduce atmospheric carbon burden only once emissions have been brought near zero.
'The idea that humanity might continue huge fossil [fuel] emissions while simultaneously balancing them with removal is nutty – you plug the leaks before bailing the boat,' he said.