Experts say emissions from current and planned energy infrastructure will take the world past 1.5°C of warming.

Researchers have looked at future emissions from current and proposed energy infrastructure across electricity generation, industry, transport, residential, commercial and other energy infrastructure.

They say if we want to avoid this tipping point, the most cost-efficient infrastructure to retire early is in the electricity and industry sectors, which make up 75 per cent of emissions but less than 25 per cent of economic value.

The study from the University of California, published in the journal Nature, Committed future carbon dioxide (CO2) emissions from existing and proposed energy infrastructure are larger than the amount that can be emitted if global warming is to be limited to 1.5°C.

Researcher Dan Tong and colleagues used datasets on existing and proposed (planned, permitted or under construction) fossil-fuel-burning energy infrastructure as of the end of 2018 to estimate future CO2 emissions.

If the proposed power plants are built and energy infrastructure continues to operate as it has done historically, these committed emissions will total approximately 846 billion tonnes of CO2.

The authors argue that without negative emissions technologies or carbon capture and storage, a global prohibition on all new CO2-emitting devices will be required to achieve a maximum warming target of 1.5 degrees Celsius.

This would include many or most of the already proposed fossil-fuel-burning power plants, as well as substantial reductions in the lifetimes and operation of existing energy infrastructure.