Five years of Greener NHS: improved carbon footprint assessment of the National Health Service in England

Five years of Greener NHS: improved carbon footprint assessment of the National Health Service in England - The Lancet Planetary Health is an update on the results and and methodology used to calculate the carbon footprint of the NHs - and how it has changed since first produced in 2019/20.

Headline figures are the reduction in emissions of 14% of the NHS Carbon Footprint (ie the emissions under the direct control of the NHS), and an improvement in the data quality by 30%. Emissions fom the NHS Carbon Footprint Plus (ie supply chain) remain static. The latest methodology includes less reliance on spend based factors from the supply chain and more individual organisational level factors. 

Data collected is from a variety of sources including Estate Returns Information Collection (ERIC) for building emissions, F-gas logs, inhaler prescriptions and volumes of volatile anaesthetics, spend based emissions from supply chains using healthcare specific Standard Industrial Classification (SIC) factors etc.

Emissions per staff FTE were 24.55tCO2e in 2019/20 and have fallen by nearly 20% up until 2024/25.

Are there areas for improvement by the NHS reporting?

Certainly, data quality has improved overall. But...Relying on spend based emission factors remains fraught with problems. An example is the use of anaesthetic agents Entonox (Nitrous oxide) which is cheap but has a very high global warming potential (GWP) compared to Penthrox which has a very low GWP, but is far more costly. Using spend based factors would put Penthrox as far worse than Entonox when the converse is actually true.