CLIENT

SITE

CONSULTANCY TYPE

Asset management: energy audit and net zero carbon strategy

ABOUT THE CRREM TOOL

The CRREM tool was developed by a research consortium across Europe including IIÖ Institute for Real Estate Economics (Austria), University of Alicante (Spain), Ulster University (UK), GRESB (Netherlands) and Tilburg University’s TIAS Business School (Netherlands).

Its purpose is to help investors better understand the ‘stranding’ risk of existing buildings. This is particularly important for buildings that are likely to need a high degree of retrofitting to meet changing market expectations and the various legal regulations being brought in by governments across Europe and the UK.

Based on the existing building and energy data, it allows investors to identify the moment an asset will become stranded based on both a 1.5 degree warming target and a 2 degree warming target.

The CRREM tool is not well-known in the UK real estate sector at the moment. However, it offers a useful method for identifying key moments on a path to net-zero and can, in turn, be mapped across to existing processes such as 5/10 year planned maintenance cost planning.

THE TASK

Claremont House is multi-storey student accommodation in Glasgow. The owner, a European property fund, had concerns about the high level of energy consumption and wanted to understand what a roadmap to net zero carbon (or as close  as was practical) would look like.  Additionally, the owner wanted to achieve a ‘B’ EPC rating under Scottish legislation.  It currently possessed an ‘F’ EPC rating.

Resero worked in conjunction with sustainability consultancy EnviroSustain GmbH.

The heating used in the building comprised of all-electric, low-cost, plug-in wall heaters. The ease of operation and control suited student accommodation but this system did not support a pathway to net-zero carbon. It was essential that any recommendations to replace systems were technically and economically viable.

The property also had a high gas load due to the use of direct gas fired centrally located calorifiers each storing 480 litres of water. In fact, gas consumption in terms of kWh was higher than electrical kWh consumption.

OUR APPROACH

Our approach involved an audit of energy consumption at the property. Unfortunately, despite the existence of sub-metering infrastructure, the energy data had substantial gaps and could only be supplied on an annual basis. This made it impossible to look at peak loads, variations and patterns of energy use.

We calculated missing data based on what information we had, energy modelling, and interviewing a number of stakeholders to better understand how energy was consumed at the property.

This revealed that electricity use in the past two years was high because two telecommunication masts were drawing off (electricity) from the landlord supply. Although one had now been decommissioned it was still drawing off electricity.

Having identified these atypical loads, we excluded this energy from whole building consumption and undertook a benchmarking exercise using the CRREM tool (see left) to identify if energy consumption for the building remained high.

Our research concluded that adjusted energy consumption was lower (better) than the benchmark up until 2024. However, if energy consumption remained constant it would be worse than the benchmark by 2029 as the UK economy heads towards net zero carbon targets.

Finally, we constructed an EPC building model to validate if the current EPC rating was correct and to determine the likely future rating based on our recommended interventions. Minimum energy efficiency standards mandating a minimum EPC rating before a property can be let do not apply in Scotland, so this requirement was to facilitate an ESG KPI rather than to ensure future regulatory compliance. Therefore, our approach considered EPC ratings alongside a pathway to net-zero but not as the final goal.

OUTCOMES

Using the CREEM tool we could see that if nothing was changed the building would become stranded in either 2029 (based on a 1.5°C target) or 2035 (based on a 2.0°C target). This would force the landlord to make significant, and probably costly, interventions to the building’s services and, potentially, fabric depending on the solutions pursued.

Our life-cycle assessment of the existing plant and MEP services found the existing heating system would reach the end of its economic life between 2022 to 2024 providing a good opportunity to undertake a more energy efficient retrofit at that time.

These calculations were also able to evidence that a new system of heat pumps, whilst requiring a greater capital investment upfront, would be more cost effective over the long term as they are 300% to 400% more efficient than the existing system, use less energy and have lower running costs.

Our recommendations included:

• Replacing the heating system with a site wide heat network using heat pumps and/or an in-dwelling unitary two-stage ventilation heat recovery and heat pump system (two-stage MVHR+EAHP).
• Replacing gas fired domestic hot water calorifiers with an electric (heatpump) solution.
• Installing an addressable LED lighting system that could also include integral ‘heat mapping’ functionality.
• Installing a small solar photovoltaic system on the rooftop.
• Engaging with student occupiers about the building’s current energy use so they can reflect on their own energy use.
• Appointing someone to become responsible for energy management. This would include collating and analysing sub-metering data so peak loads and patterns of energy use could be better analysed to improve energy efficiency even further.

We calculated that these recommendations would reduce gas consumption by 100%, electrical consumption by 12% and reduce carbon emissions by approximately 90 tonnes. They would also improve the building’s resilience and secure a ‘B’ EPC rating.