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German government warns of dangerous water pollution and public health threat from heat pumps

Global Warming Policy Forum

London, 3 June – In light of a public health warning by the German government, the Global Warming Policy Forum (GWPF) is calling on Boris Johnson to halt the planned rollout of heat pumps and to undertake an environmental impact assessment before rushing into a public health fiasco.

In recent days, the German Federal Environment Agency (Umweltbundesamt) has published a major study detailing the pollution threat to water supplies and public health from modern refrigerants commonly used in air conditioners and heat pumps.
The UK government is currently planning a ban on gas boilers and the rollout of air source or ground source heat pumps for most of the country’s 26 million households, promising installation rates of 600,000 a year as soon as 2028.
The pollution threat posed by heat pumps arises from the atmospheric decay of leaking gases used as refrigerant in these devices. These gases, initially hydrofluorocarbons (HFCs) and more recently unsaturated hydrofluorocarbons (u-HFCs and u-HCFCs), were adopted because they are less harmful to the ozone layer and have a lower global warming potential than the chlorofluorocarbons and hydrochlorofluorocarbons that were phased out under the Montreal Protocol.
However, these refrigerants decay in the atmosphere to produce trifluoroacetic acid (TFA) and/or trifluoroacetate, which then passes into groundwater and drinking water, raising serious public health concerns. The German study notes that the emissions from air conditioning and heat pumps will “add a large additional share to the amounts of TFA or trifluoroacetate in the atmosphere.”
This problem is of particular concern because TFAs and trifluoroacetate are very difficult to remove from water, and break down only very slowly. The German government’s report observes:

Due to the extremely high persistence and mobility of TFA and trifluoroacetate, the increasing use of halogenated substitutes with low global warming potentials leads to growing pollution of the groundwater and drinking water resources. Since persistent substances remain in the environment for a long time and neither effective natural mechanisms nor acceptable technical processes for removing TFA from drinking water resources are known, potential harm to the environment and humans can only be prevented by minimizing the input of TFA and its precursors. Even if the deposition of TFA and its pre-cursors were to cease immediately, an extremely long-lived substance such as TFA or trifluoroacetate would remain in the environment for at least several decades.” (p. 47)

The report concludes that air conditioners and heat pumps are already adding significant amounts of trifluoroacetate acid (TFA) to the atmosphere, contaminating rain and water supplies, and potentially causing health problems such as liver and kidney damage.

Alternatives to the refrigerants currently employed in air-conditioning and heat pumps already exist, the so-called “natural refrigerants”, including ammonia, carbon dioxide and hydrocarbons (isobutane is already widely used in domestic fridges) but they have drawbacks of their own, ammonia being toxic and isobutane inflammable.
Dr Benny Peiser, director of the GWPF, said:

In light of the serious health risks of heat pumps revealed by the German Environment Agency, the government should halt its plans and undertake an environmental impact assessment of current heat pumps before rushing knowingly into a public health fiasco.

The rollout of heat pumps is a classic case of over-hasty activism with unintended consequences. Refrigerants adopted because of concerns about ozone layer damage and global warning potential turn out to have serious public health risks because of dangerous effects on drinking water.

Fortunately, this has been discovered before the UK government forced the entire population to move to heat pumps using exactly these modern refrigerants. There are alternatives, but whether they will work as well, or be as economic, remains to be seen.

The German government’s warning is yet another reason, as if any more were needed, to halt the UK’s rush to heat pumps. With every passing day this looks more and more like a leap in the dark.”

Further information

German Federal Environment Agency: Trifluoroacetic acid from fluorinated refrigerants contaminates rainwater

Heat pumps may cause dangerous water pollution, report warns