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Part of Sustainability Annual Report 2020-21

Annex 4 technical appendix

Current Chapter

Current chapter – Annex 4 technical appendix

This annex is intended to provide technical detail in line with the requirements of the HMG annual public sector sustainability reporting guidance and make transparent our decision and methodologies.

Scope of reporting

An equity share approach has been taken to building utility reporting – electricity, gas, and water. This means we have reported against our whole estate footprint rather than the partial reporting scope of the Greening Government Commitments (GGC). Our GGC figures are shown in this table. 

Metric Unit 2013/14 2014/15 2015/16 2016/17 2017/18 2018/19 2019/20 2020/21
Electricity kWh 4,492,733 3,683,799 3,912,435 5,590,629 5,574,130 5,952,435 *6,085,779 5,451,947
Gas kWh 1,911,633 2,096,560 1,597,092 1,778,653 1,846,070 2,033,892 *1,745,898 1,978,675
Water M3 10,543 10,387 10,923 12,935 17,321 17,231 *16,423 9,823

*Corrections following published report occurred resulting in the changes in the 2019/20 reported GGC figures

Baseline year

Due to data quality and availability across all compulsory metrics we have chosen to re-baseline from the standard 2009/10 period to 2013/14.

This is when NHS Digital was set up in its current form as the Health and Social Care Information Centre (HSCIC) and, as such, full data sets become available for all the constituent parts. This has made reaching our targets more ambitious as we have mirrored Greening Government Commitments (GGC) targets which meant 4 years less to achieve them.

Normalisation metrics

Performance is generally reported in absolute terms as the nature of sustainability challenges means that the goal is zero net damage. In addition to this NHS Digital has grown significantly in terms of FTE over the reporting period which makes absolute targets more challenging.

Whole estate Gross Internal Area (GIA) and FTE normalisation metrics are as follows if the reader would like to assess in more detail. FTE includes capitalised workers as well as permanent, temporary and secondees.

2013/14 2014/15 2015/16 2016/17 2017/18 2018/19 2019/20 2020/21
FTE 2,137 2,400 2,746 2,857 3,335 3,367 3,079 3,033
GIA (m2) 18,397 21,439 20,508 20,508 21,872 21,595 20,622 20,622*

*We consolidated much of our Leeds estate in 2020/21, resulting in a significant reduction in our Gross Internal Area, however this will be reported in the 2021/22 dataset.


In general materiality has been viewed through the carbon lens. Therefore, elements such as waste production and paper use are far less material and as such have received less focus.

Carbon analysis

Carbon analysis has taken place using Greening Government Commitment (GGC) carbon conversion factors and further Department for Environment, Food and Rural Affairs (DEFRA) conversion factors where necessary.

Renewable electricity sources covered by Renewable Energy Guarantees of Origin (REGO) certificates have been reported as grid average carbon so that fair consumption-based comparison can be made with previous years. The savings noted in the report are indicative only and not included in the carbon savings reported.

Data verification

Multiple internal and external audits have taken place on our data sets in 2018/19/20/21. These include audits by 3rd party independents for verification purposes and an internal process has been set up for annual verification with the finance team.

Data sources

Metric Accurate/estimate Source
Generator fuel use A Invoices
Gas/electricity/water A Accounts/invoices/meter reads
Data centre electricity A Accounts/invoices/meter reads
Outsources data service E Extrapolated from data snippets
F-gas leak tests A Leak test certificates
Lease cars/grey fleet Expenses system mileage claims 
Taxi/tube E Extrapolated from spend
Hotels/flights/trains A Travel booking data
Virtual meetings use E MS Teams MI
Building waste E Estimated from volumes, frequency, and office occupancy
ICT waste A Contractual MI 
Paper use A Printing quantity MI
ICT hardware E Spend to carbon conversions
Hyperscale Cloud E Estimations provided by suppliers

Data corrections and developments

A modest data issue has come to light for 2015/16-19/20 gas and water consumption (and carbon metrics). This is due to errors being uncovered in the previous data sets which lead to a slight under reporting of gas and over reporting of water for our Bridgewater Place building (vacated end of December 2020). A view has been taken that as this issue does not affect the baseline year of 2013/14 and has been corrected for the current reporting year (2020/21) we will not undergo a change in the previously reported data.

New metrics are being added to the data set over time and corrections are made where new data becomes available. For example colocation data centre energy use for 2019/20 has been updated to actual data from an previous estimate in the 2020/21 report.

External data storage has been a major area of data development during 2020/21, with information added in for our outsourced data services in our baseline year (2013/14) and more recent impacts from colocation and cloud.

Work to assess the broader procurement activities will be undertaken in 2021/22, as these have not been completed in 2020/21. Similarly, work will be undertaken to assess the carbon, cost and consumption impacts of remote working as we move toward hybrid working. At that point, the dataset will be nearing completion.

Data anomalies

It is recognised that within this report there are several aspects of our data that may seem unusual due to the nature of the year we are reporting against. These will be explained in full in this section.

We would have expected to see a substantial reduction of printing this year. However, there have been 296 reams (equivalent to 148,176 pages) of paper printed. This is because we needed to mobilise employees and kit to enable effective remote-working during the pandemic which resulted in a lot of courier deliveries and label printing, as well as Facilities Management office preparation and the provision of adequate health and safety related notices in relation to maintaining our COVID-secure offices.

Recycling figures are nearly as high as our previous reported year. Whilst we have seen a significant drop in office utilisation, a large proponent of the waste recycled this year is due to the exit of four of our office buildings into one single Government Hub in Leeds. This has resulted in a large amount of office furniture waste being responsibly disposed of, being either recycled or reused. The Estates team have done a phenomenal job at appropriately managing the waste out of the buildings, ensuring that furniture and other peripherals like ICT equipment are appropriately recycled or reused where appropriate.

Last edited: 19 January 2022 7:39 am