Building a better, cleaner and healthier future for residents and visitors alike, is a key success factor for Sunderland City Council as it strives to grow a dynamic, vibrant and healthy smart city.
And becoming carbon neutral – both as a council and as a city – is a key part of this growth as we recognise and commit to global sustainability objectives and ambitious targets set out in our city-wide Low Carbon Framework and in Sunderland City Council’s Low Carbon Action Plan.
As we make progress towards this goal, we know that it requires a strong partnership approach to pool expertise, resources and delivery. One particular key partnership has seen the council and Digital Catapult contract with Nomad Energy Solutions (Nomad) for a pilot project, based on council-owned office buildings, with the aim of building a roadmap to enable council buildings to become net zero by 2030.
Two buildings were chosen for the pilot:
- Evolve Business Centre
The Evolve Business Centre is a 3-storey office building, built and occupied in 2006, and situated in Houghton-le- Spring. Businesses can access the building 24/7.
- Leechmere Estate
Leechmere Estate comprises of two conjoined legacy buildings of different construction and age: Leechmere Centre (LC) and Independent Living Centre (ILC). The site operates 24/7, with only partial occupancy out of office hours.
The scope of work for the pilot was to:
- Provide a transition route to decarbonise heating and cooling
- Identify energy saving opportunities
- Show a way to scale the results to the wider council estate
A principal focus for both buildings was fossil fuel heating, which was identified as the area offering most affordable impact from the project by employing energy efficiency and heat decarbonisation key measures.
The Evolve building is air heated by a refrigerant heating and cooling system, supported by a separate ventilation system providing tempered air. To understand the energy performance of the buildings, data was obtained from the energy utility providers, the Council’s Trend Building Management System (BMS), drawings provided by the council and a sensor array installed by Nomad collecting data on temperature and CO2 levels.
Nomad used the insights generated from the data analysis to identify quick wins in terms of energy performance improvements, leading to CO2 and cost reductions.
Nomad’s recommendations surrounding the process to decarbonise the Evolve Centre were:
- Substitution of the gas heaters in the Air Handling Unit, either by server room chiller heat recovery or a separate heat pump option
- Reconfiguration of air intake to server rooms with a new concept using fresh air
- Evaluation of the viability for a proposed local PV array to decarbonise electricity for Evolve, including heating
At Leechmere, the building units have separate heating and ventilation systems, but the incoming electricity and mains gas are for the entire building. To understand the energy performance of the building, data was obtained from the energy utility providers, drawings provided by the council and a sensor array installed by Nomad collecting data on temperature and CO2 levels.
Nomad again used the insights generated from the data analysis to identify quick wins in terms of improved energy performance, leading to CO2 and cost reductions. Principal early findings focused on reducing average room temperature and balancing/segmenting the heating system to reduce energy usage.
Nomad made the following recommendations around the process of decarbonising Leechmere:
- Options for fabric improvements including upgrading window glazing
- Re-configuration of the heating system to enable targeted management out of office hours and reduced temperature levels making the building units ready for a net zero transition. The re-design of the plantroom should include the removal of the header separating boiler and distribution circuits
- Connection of the ILC heating system to the oversized LC boilers installed in 2021, rather than replacing ILC boilers
- Replacement of fossil gas as part of a managed asset investment programme. Heat pumps or biogas would appear to be the best available technologies for the Leechmere Estate energy transition
- Decarbonisation of the electricity for Leechmere should include a solar PV array
The move towards net zero can be planned while the existing building systems are in the process of optimisation to establish a new baseline based on the changes recommended. This minimises disruption to ‘the norm’, whilst improvements are embedded.
Change was able to be actioned quickly at Evolve, working closely with Sunderland City Council’s Energy Management team. One example is that, based on the recommendations,
Sunderland City Council has reduced the frost protection burner setpoint for the ventilation heat recovery unit from 15oC to 5oC and has cut gas demand by 50% with no capital investment costs. This is expected to save approximately 15 tonnes of CO2e annually. Solar PV is also now installed and will be complemented by battery storage shortly.
Nomad identified another potential energy saving at no cost by ensuring an optimal temperature was maintained in the building depending on the time of day. During office hours the building is now maintained at 21°C, out of office hours this temperature automatically reduces. Since the building is generally not occupied at night, the cost saving by a night setback is estimated to be around £6k annually.
Similarly, at Leechmere, Nomad identified further energy saving potential simply by reducing the electric frost protection setting for the AHU.
The next tranche of optimisation actions can be delivered at both locations over the next 6 to 24 months and will save energy and money, reduce CO2 and stabilise energy profiles.
Smart building solutions and the more efficient management of energy, building management and usage – and an approach which is strategic and co-ordinated, aligning to requirements for EV charging infrastructure and wider building maintenance – are essential to drive our journey to net zero and ensure ongoing efficiency improvements.
Sunderland City Council and Nomad are also now exploring options to scale up the solution to the council’s wider estate.