It is a problem bedevilling households across the UK: what can we do with the mountains of food-spattered plastic waste left in our bins?
Now a group of scientists say they have the answer – by using the detritus of domestic life to heat homes.
Researchers at the University of Chester have found a way to turn dirty plastic waste into hydrogen, which can heat homes and fuel cars without producing greenhouse gas emissions. The process uses a glass kiln, heated to 1,000C, to instantly melt unrecyclable plastic that releases a mix of gases including hydrogen.
The technology will be used commercially for the first time at a plant near Ellesmere Port in Cheshire later this year after a pair of “waste-energy” companies agreed to invest.
Peele Environmental, the owner of the plant, said the project could help keep 25 million tonnes of “contaminated” plastics, which cannot be recycled, from ending up in landfills or the ocean. Hydrogen could play a key role in helping the UK meet its climate targets by replacing traditional gas used for decades in stoves, radiators and boilers. It could also replace petrol and diesel in cars, vans and buses.
“Surely the world must wake up to this technology,” said Professor Joe Howeof the University of Cheshire. “It will make waste plastic valuable with it being able to power the world’s towns and cities, and most importantly it can help clean up our oceans of waste plastic now.”
However, similar plans have raised concern among environmentalists in the past. Although hydrogen is not a greenhouse gas, the process of creating it from plastic releases methane and carbon monoxide, both potent greenhouse gases.
The Cheshire project plans to trap the gases and pipe them into a power plant to generate electricity. This would not be any more polluting than the UK’s existing gas-fired power plants, and would avoid the need to extract more gas from the ground.
The university researchers developed the project alongside Powerhouse Energy, which hopes to take the technology to Japan and south-east Asia, where hydrogen-fuelled buses are already on the roads.
The developer said that Japan’s ministry of economy, trade and industry has written to the company in support of its plans, and believes it could offer “many environmental advantages”.
The gas-generated electricity could help to wean the energy-hungry economies off coal-fired electricity, which is still wide-spread in Asia and produces almost double the carbon emissions of a typical gas plant.
In the UK, the government’s climate watchdog, the Committee on Climate Change, has warned that it will be “essential” for hydrogen-makers to trap and store any carbon emissions to be compatible with the government’s targets.