# Building Management Systems (New)

For this intervention, details of all funded NHS Energy Efficiency Fund projects, split between project types were used for the Healthy Returns Report. From this data, Ashford and St Peters was identified as a representative example of roughly average electricity use. Annual financial and CO_{2} emissions savings were then calculated based on this example, these results are scaled up to the number of NHS Trusts and, in the Healthy Returns report, presented as the net present value of the five year savings. The wider social savings of reduced carbon emissions were also calculated based on the social costs of carbon.

**Case study source**

Energy Efficiency Fund (EEF) Report

Healthy Returns – Production Reports

**Financial Calculations**

The cost of the intervention has been identified at the Ashford and St Peters Trust were £643,000. This has been scaled by the number of Trusts (not including independent trusts), which has been estimated as 245, but also taking into account that an assumed 75% of sites will be suitable. This has been calculated for Healthy Returns as a cost of £80,696,500 across the whole NHS annually. So adjusting for the 75% applicability rate to give the total possible cost gives approximately £110,000,000.

Total Savings scaled to the whole NHS have been calculated as £97,038,106 over 5 years. This takes into account a 75% applicability rate, so adjusting for this the total possible saving over 5 years would be £130,000,000 and therefore an annual saving of £26,000,000 would be achievable through implementation of BMS systems from scratch across the NHS.

It should be noted that whilst an applicability rate of 75% was used in the calculations for the Healthy Returns report, a more conservative uptake rate of 13% was used in the calculation for the MACC.

**Carbon Calculations**

Carbon saved over a 5-year period has been quantified for the Healthy Returns report as 897,556 tCO_{2}e. This takes into account a 75% applicability rate, so adjusting for this the total possible saving over 5 years would be 1,200,000 tCO_{2}e and therefore an annual saving of 240,000 tCO_{2}e would be achievable through implementation of BMS systems from scratch across the NHS.

The MACC calculations take into account an uptake rate of 12.5% for NHS Trusts, assuming that many will already have some form of BMS or be unsuitable for such a measure.

**Assumptions**

- Carbon savings were prospective
- Assume social benefits in case study are social cost of carbon
- Ashford and St Peters as representative example