The University’s Sustainability Strategic Plan has the ambition to be net-zero for its Scope 1 and 2 emissions by 2030. Fulfilling this ambition requires addressing our energy utilisation, in terms of power and heat, as well as implementing energy efficiency measures through building refurbishment and behaviour change.
Rooftop solar PV system in Building 37, Highfield Campus
The Strategy will also require us to look at opportunities to develop local power sources, including deploying solar photovoltaic (PV) systems into our infrastructure, such as building roofs and car parks. To address this, the Sustainability Implementation Group (SIG) has undertaken a detailed assessment of the potential of such deployment, evaluating both the technical power potential and financial feasibility (return on investment) of deploying rooftop solar PV systems across University buildings.
Using high-resolution data of buildings heights and hourly dynamic solar simulations, the optimal locations for PV installation on our campuses have been identified. These can be accessed through a developed interactive modelling dashboard, giving indication of building and campus potentials.
Geospatial data processing combined with hourly solar radiation modelling were used to assess rooftop characteristics (chimneys, equipment on roofs etc), shading from other buildings and/or trees, to arrive at optimum deployment areas, and overall solar PV power generation. Figure 1 shows an example for PV power for all building on the Highfield campus, and how this relates to current electrical consumption.
Figure 1: Solar Dashboard showing building-level potential solar generation in relation to electricity consumption.?Click on image for clearer view
The financial return on investment (ROI), is summarised in Table 1. A fully realised rooftop PV deployment could offset around 16.5GWh of electricity annually providing an annual saving of ~?5.5million and a payback period of ~3 years. Funding will be needed to procure the PV systems, conduct building surveys to inform and refine modelling so that the necessary evidence can be provided to support funding applications. Opportunities for large-scale solar installation sites were also reviewed. For example, the University’s Wide Lane Sports Complex was found to have an estimated capacity of up to 0.75MWp, potentially generating over 0.7GWh/year.
Estates and Facilities have access to the outputs from the tool and are planning to develop win-win projects to support solar deployments on university buildings.
| Metric | Value |
| Total Rooftop PV Capacity | 16.7 MWp |
| Electricity Offset Potential | ~16.5 GWh/year
Percentage offset |
| Estimated Annual Cost Saving1 | ~?5.5M |
| Cost of system & installation2 | ~?15.5M |
| Rooftop PV RoI2,3 | 33–38 months |
1Based on an electricity grid price of 33p/kWh.
2Based on an installation cost of ?860-?1,000/kWp.
3RoI currently excludes the potential need for building/rooftop modification
It must be noted that any deployment on buildings will also need to consider their structural integrity and availability of appropriate power connections. The modelling and interactive dashboard are being developed to incorporate these requirements, supporting strategic decision-making on building refurbishment and long-term energy planning.