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Core Carbon footprint of NHS Trusts and Foundation Trusts – emissions per full time equivalent

Independently assured by the Information Governance Board (IGB)

Published by
Sustainable Development Unit
Assurance Date
13 Sep 2018
Reporting level
National, Regional, Trust
Reporting period
Review date
13 Sep 2023
Based on data from
Carbon Valuation, Department for Business, Energy and Industrial Strategy
Geographic Coverage


This indicator provides a national quantification of the carbon impact of core emissions by NHS providers per FTE. This allows measurement of progress by NHS providers emissions linked to the potential fluctuation in staff which provides both a proxy for changes in activity e.g. patient activity but also allows an organisation to normalise its emissions based on its own growth or reduction.


The competitive process of tendering to deliver services means that a Trust may shrink or grow each year, or where trusts merge this allows a better method to assess emissions over periods of flux and transition. Emissions per FTE is a well-used indicator in other industries;  e.g. a KPMG report here;


This indicator will provide a consistent approach to measurement of and for improvement in carbon emissions by providers – such as demonstrating progress to commissioners of carbon reduction in core emissions.

The Climate Change Act (2008) was introduced to ensure the UK cuts its absolute carbon emissions by 80% by 2050. The 80% target is set against a 1990 baseline.


The act enables the UK to become a low carbon economy. It sets in place a legally binding framework allowing the government to introduce measures which will achieve carbon reduction and mitigate and adapt to climate change.


As the largest public sector emitter of carbon emissions, as the NHS is responsible for over a third of all public sector emissions, the health system has a duty to respond to meet these targets which are entrenched in law.  Contributing to the Climate Change Act target with a 34% reduction in carbon emissions by 2020 is a key measure of our ambition across the country.  Reduced environmental impact will be measured against the target of 34% reduction in CO2e emissions by 2020 and be well placed to meet the 80% target by 2050.The health and social care system has the most to gain from reducing greenhouse gas (GHG) emissions from its own activity due to the severity and diversity of impacts of GHG emissions on human health.

Annual measurement allows the assessment of progress against the Climate Change Act targets and granularity of sources and activity linked denominator allows a broader level assessment of yearly changes in emissions to allow a targeted approach to the reduction in GHGs and the associated effects on human health


The amount of core emissions as Carbon Dioxide equivalent (greenhouse gases) emitted by NHS Trusts and Foundation Trusts (which will be referred to as ‘Trusts’ or ‘providers’) inclusive of Scope 1, 2 and 3 emissions (where within reporting boundaries and inclusive of well-to-tank (WTT) emissions). The cost of carbon or (central) non-traded cost of carbon is an economic evaluation of emissions impact on society; this helps demonstrate how the NHS needs to reduce the impact of this cost as per the targets in the Climate Change Act (2008). The indicator helps comparison between organisations and years. The NHS as a system should ‘do no harm’ and to improve the sustainability of the system, we must reduce this impact on health and society to truly create a holistically sustainable NHS system.


The SDU currently segments emissions in this way, please note this indicator covers core emissions only:


  • Core: Scope 1, 2, 3 and WTT emissions from energy, waste, water, business travel and transport and anaesthetic gases (as a fugitive emission)
  • Supply chain: All scope 3 emissions from ‘non healthcare provider’ supply chain – this include the extraction of raw materials, their transport and processing in usable items used by NHS providers, e.g. oil transported and processed into plastics such as syringes and packaging
  • Community: All emissions (Scope 1, 2, 3 and WTT) from staff commute, patient and visitor travel and inhaler use.


The indicator will include a national level figure of all NHS providers in England, by NHS England regions (North, South, London plus Midlands and East) and by trust type;


  • Ambulance
  • Mental health and learning disability
  • Community
  • Care
  • Acute – Small
  • Acute- Medium
  • Acute – Large
  • Acute – Specialist and Multi-service (this category is merged due to the low number of Specialist and Multi Service Acutes)
  • Acute Teaching


Emissions will be reported per FTE;

  1. Emissions per full time equivalent directly employed by NHS providers Estate (as reported in NHS Digital workforce data)  - (TCO2e/FTE)


NHS Trust staff FTE data will be taken from

How this indicator is calculated


Estate Return Information Collection (ERIC);


“The ERIC (Estates Return Information Collection) is collected and published … by NHS Digital on behalf of the Department of Health. It is the main central data collection for estates and facilities services from the NHS containing information dating back to 1999/2000 and will be added to as future returns are completed. The data provided enables the analysis of Estates & Facilities information from NHS Trusts …. in England which is a compulsory requirement that NHS Trusts submit an Estates Return. The data is as provided by reporting organisations and has not been amended. The accuracy and completeness is the responsibility of the reporting organisations.”


The government annually updates a recognised set of carbon conversion factors each year available from;


Ambulance Trusts report their fuel usage annually via Green Environmental Ambulance Network (GrEAN) and is provided to the SDU via Yorkshire Ambulance Trust.


NHS Digital also provide an Organisation Data Service (ODS) which provides details of all NHS Trusts with an individual ODS code – which is used in ERIC as well and provides location and regional information used in the creation of any regional/spatial analysis. And NHS Digital’s Hospital Episode Statistics (HES) are used and applied to an average bed usage of N2O for all providers – this assumption is only used in demonstrations of the indicator pre- 2017/18 as N2O data will be available from either ERIC and/or the model hospital from 2017/18 onwards.


NHS Digital sources are also used;


NHS Trust staff FTE data will be taken from


NHS Workforce Statistics - April 2017, Provisional Statistics: Organisation tables – table 4 Time series of Staff Totals by Health Education England area and Organisation - Full Time Equivalents


The data is provided monthly – first the numbers for trusts only relevant to the 2013/14 – present years has been used. The average of each of the 12 months relevant to each financial year has been used.

This data only covers the impact of emissions for treatment/services undertaken by NHS providers and doesn’t include impacts from services commissioned by the NHS for private healthcare delivery


The numerator is tonnes of carbon dioxide equivalent or TCO2e


TCO2e factors in all greenhouse gas emissions (GHGs) such as Methane (which is per kg 25 times more potent than CO2) and Nitrous Oxide (which is 298 times), weighting them according to their potential to cause global warming to provide one single figure;



The indicator takes the above TCO2e data and then divides by the number of FTEs employed by NHS providers;

1.        Emissions per FTE (TCO2e/FTE


Numerator divided by the sum of all FTE’s that are employed by NHS trusts in England.


  • An explanation of the value of monitoring the use of anaesthetic gases in core CO2 emissions is required
  • Acknowledge within the data source that the carbon cost of treatment at private providers paid for by the NHS is not captured
  • For the indicator on social cost of CO2 emissions, clarify that a cost multiplier is applied to the core emissions data rather than a denominator
  • Determine whether there is any value in the data for 2015/16 in charts 1 and 2 as they are noticeably different from other years

Interpretation Guidelines

Description of Scopes;

Scope 1 (direct emissions) emissions are those from activities owned or controlled by your organisation. Examples of Scope 1 emissions include emissions from combustion in owned or controlled boilers, furnaces and vehicles; and emissions from chemical production in owned or controlled process equipment.


Scope 2 (energy indirect) emissions are those released into the atmosphere that are associated with your consumption of purchased electricity, heat, steam and cooling. These indirect emissions are a consequence of your organisation’s energy use, but occur at sources you do not own or control.


Scope 3 (other indirect) emissions are a consequence of your actions that occur at sources you do not own or control and are not classed as Scope 2 emissions. Examples of Scope 3 emissions are business travel by means not owned or controlled by your organisation, waste disposal, materials or fuels your organisation purchases. Deciding if emissions from a vehicle, office or factory that you use are Scope 1 or Scope 3 may depend on how you define your operational boundaries. Scope 3 emissions can be from activities that are upstream or downstream of your organisation.  More information on Scope 3 and other aspects of reporting


Scope 3 WTT (other indirect) include the emissions from the production of fuels, such as oil refining or fuel distribution  associated with the production of creation of the activity, e.g. manufacture or transport


Out of scope factors are used to account for the direct carbon dioxide (CO2) impact of burning biomass and biofuels. The emissions are labelled ‘outside of scopes’ because the Scope 1 impact of these fuels has been determined to be a net ‘0’ (since the fuel source itself absorbs an equivalent amount of CO2 during the growth phase as the amount of CO2 released through combustion). Full reporting of any fuel from a biogenic source should have the ‘outside of scopes’ CO2 value documented to ensure complete accounting for the emissions created.