CASE STUDY: AECOM

Public Sector Decarbonisation Scheme (PSDS) Delivery

Many local authorities have made significant carbon reduction commitments with limited resources to achieve these. As such acquiring funding through the Public Sector Decarbonisation Scheme (PSDS) has played a huge role in enabling public sector clients to transition to lower carbon consumption for their buildings. AECOM has supported a number of our Government sector clients in achieving their carbon reduction targets through developing grant applications for PSDS funding & subsequently delivering projects.

To secure funding we used our in house bespoke energy audit tool to identify opportunities and quantify savings from implementation of projects. We completed grant applications and supporting reports and calculations. This resulted in successful funding to the tune of £12m.

Once funding was secured we then also supported our clients in the development of the projects. We provided a full multidisciplinary role taking the proposals through design development, statuary approvals and DNO reviews then progressing the scheme through procurement and management of the contractor on site.

Key measures which we are implementing are:

– Draft proofing

– Roof / loft insulation

– Window upgrades

– Cavity wall insulation

– LED lighting

– Heat Pumps

– PV (Photo Voltaics)

– Solar Thermal Hot Water

– Water Flow restrictors

– New BMS Controls

– Battery Storage

– Metering & sub-metering

The schemes have all been balanced to ensure there is no increase in operational cost due to the switch from the use of gas to electricity. This achieves all round benefit to the public sector organisations.

 

Key Features

– 12m Grant funding secured

– Upgrade works designed and specified at 35 buildings

– 3000+ tonnes CO2e savings per annum through delivered projects

 

Key Challenges

Programme – the timeframe from grant award to completion was 9 months. This resulted in some challenges to overcome with the design. One solution can be seen in our approach to heat pumps. As the timescales did not permit ground source heat pumps (due to lack of time to optimise piles) or water source heat pumps (due to time to obtain permits) we designed heat pumps which were purely air sourced.

COVID – As the delivery of the project was programmed during periods of lockdown we needed to minimise work within operational space and as such we could not change secondary systems. Our solution was to operate the heat pumps only when the external temperature is above 7 degrees. This means that the secondary systems can meet the load at the lower operating temperatures during warmer periods but can shift to the higher secondary temperatures from the existing gas systems on the occasions that the external temperature drops significantly.