A site wide Digital Twin was created to show the energy and carbon baseline results across the park. The first three buildings below had detailed Digital Twins created using the VE, IES’ flagship building performance simulation software, while the remaining two were simulated using the ICL master planning tool, iCD, which enables quick and easy modelling and analysis. 

Pollok House, the ancestral home of the Maxwell Family, is a historical grade A listed building constructed in 1752. It currently operates as a museum with a café. Its listed status presents a challenge to reaching net-zero, with certain retrofit measures and fabric improvements not possible. Due to the building’s old stone walls, it has high heating requirements and issues with damp and condensation.

The Burrell Collection is a large art gallery in the middle of the park. It has very high energy demands due to its large floor area, as well as having specific cooling and dehumidification requirements to preserve the exhibits. 

The Courtyard buildings are also A listed, with some of the constructions dating back to the 14th century. Most of the buildings are currently closed, with only small sections currently being used. There are plans to re-build and re-open the buildings as a visitor centre and stables for Clydesdale horses. 

Knowehead Lodge is a small building used as office space, while The Police Dog Pound is used for training police dogs in the park.

IES consultants collected data on all the buildings to populate the digital twin, including data on planned site improvement measures to show their impact in terms of potential energy and carbon reductions.

Pollok House
Pollok House has recently upgraded its oil boilers with high efficiency condensing gas boilers and low energy LEDs fitted throughout the building. There was limited scope for simulating other potential improvements, such as wall insulation or double glazing, due to the building’s A listed status.

The low energy LEDs, combined with there being no electrical heating in the post upgrades scenario, created a 51% reduction in total electricity consumption. The new gas boilers only reduce the heating fuel energy consumption by 7.4%, however as natural gas has a lower carbon emissions factor than heating oil, the carbon saving is greater than the energy saving. The total energy saving from both improvements is 12.8%.
These improvements reduce the total carbon emissions of the building by 30%, from 182 tons to around 127 tons. 
The Burrell Collection
The Burrell Collection has undergone an extensive refurbishment with fabric and lighting improvements, and a PV array installed on the roof. The refurbishment provides a 33.9% reduction in natural gas consumption of the building, mainly by reducing space heating demands. Other improvements, such as new LED fittings and the PV, contributed to a total energy saving of 25%.
The fabric improvements helped reduce the space heating energy demands of the buildings, so they are proportionally less compared to other buildings in the park. However, the Burrell Collection has very high auxiliary energy demands, mainly arising from it having a mechanical ventilation system, unlike Pollok House and the Courtyard which rely on natural ventilation. The building also has some cooling demands in summer, and dehumidification demands in Spring, Autumn and Winter, which the other buildings do not have.

The buildings’ carbon footprint from energy consumption is around 406 tons, which makes up the majority of the site’s total emissions. The bulk of the 25% savings comes from the fabric improvements. Of the 134.7 tons of emissions saved, only around 12.6 are avoided through the PV generation; the rest is due to the thermal performance improvements.
The Courtyard
Five different scenarios were modelled for the Courtyard based on how the buildings could operate after partial rebuild and renovation. Scenario one being if the Courtyard was rebuilt with the same construction materials as it currently has, with no fabric improvements and using electric boilers or direct electric heating systems for space heating. Scenario 5, the most efficient, included all the energy conservation measures from each scenario combined. This included double glazed windows, better roof insulation, water source heat pumps, contributions from the planned hydroelectric turbine, and the addition of a 2MWh electric battery storage, to store excess energy generated for later use, when the river flow rate and turbine output drops. 

Scenario 5 would bring the total annual carbon footprint of the buildings’ energy consumption down to just 4.4 tonnes, compared to 119.4 tonnes in scenario 1. 

Modelling the individual heat and electricity networks at the park using IES' Intelligent Virtual Network tool, iVN, provided an accurate holistic view of when and how the park is using energy. This delivered insights into the most effective way to decarbonise these energy demands. The planned installations at the Burrell Collection and the Courtyard were modelled, as well as looking at potential future scenarios that could further reduce the park’s carbon footprint.

Different scenarios were modelled to determine what would be required to fully decarbonise the energy demands of the Burrell Collection. As the heating demands are so high, the electrification of heat through heat pumps was discounted as it would vastly increase the electrical demands that are already difficult to meet with onsite generation. Decarbonising the heat of the building may be more straightforward in the future, when a hydrogen resource may be available which could potentially be used in a hydrogen ready CHP system.

For decarbonising the buildings’ electrical requirements different scenarios were modelled looking at different sizes of PV panels and storage, as well as other technologies such as wind turbines. These were added to the network, shown in the diagram below, assuming that the 500kW of CHP and further 80kW of PV panels were also already installed.


It was found that adding more PV panels would be more effective than adding a wind turbine for decarbonising the Burrell Collection’s electricity. While the wind turbine did produce a consistent amount of electricity throughout the year, the building requires more additional generation during the summer months and doesn’t need any in the winter months, as can be seen in the table below. Generation from a wind turbine would therefore be wasted during the winter months when the battery is already likely to be fully charged most of the time. There may also be difficulties in obtaining planning permission for a wind turbine in the park.


To fully decarbonise the building’s electricity it was found that around 3000m2 of extra PV panels in addition to those already on the building would be required, as well as increasing the battery storage from 1.856MWh to 3.2MWh. If the energy loads of Knowehead Lodge were also included then the storage may have to be increase to 3.5MWh. This would require a significant monetary investment, but it should allow for all electricity use of the Burrell to be provided on site from the PV and CHP installation, requiring no grid imports. 3000m2 may seem like a very large area for a PV array, however it is less than a third of the total area of the building’s car park. The residual electricity demands on this microgrid at the Burrell Collection for the scenario including Knowehead Lodge is shown below.


For the Courtyard buildings, it was found that nearly all of the building energy demands can be met from on-site renewables and storage, therefore little additional generation is required for carbon neutrality. As the turbine output tends to drop in summer months, PV panels are perfectly suited to supplement the energy system here. An array of 50kW (around 400m2) would be enough to make the building’s energy use completely carbon free. 

An investigation was undertaken into how much additional generation would be required at the Courtyard network if Pollok House was connected into it. The electrical demands of Pollok House were incorporated into the network model while trying to keep the energy use carbon neutral. This network model can be seen in the diagram below. If just the current electrical demands of Pollok House were to be added in, then the battery storage capacity would have to be increased from 2MWh to 3MWh, and the PV installation would have to be increased from 50kW (around 400m2) to 80kW (around 600m2). 

The network was also modelled for the option of the heating demands of Pollok House being electrified, and supplied by a ground source heat pump. Due to the building’s high heating loads, this would greatly increase the amount of electricity required from the network. However, carbon neutrality could still potentially be achieved through increasing the PV array to 120kW (around 950m2), increasing the storage size to 4MWh, and adding another 60kW hydroelectric turbine upstream in the White Cart Water.

The results from all simulations have been uploaded to IES’ online data analysis platform (iSCAN), and connected to live dashboards. These allow the energy, carbon and cost results for each individual building, and site-wide, to be viewed at a glance, with some more detailed analysis too. Any future simulations will automatically feed new data to the dashboards to keep them updated.

Two versions of the dashboards were created: one with a more technical audience in mind, and a less-technical version that could potentially be displayed to the public. The technical dashboards contain more detailed tables and graphs, giving greater insight into how and when the park is using energy and producing carbon.

The less technical version contains more easily digestible high level information, with cards showing rough equivalents for the energy or carbon results. For example, the 127 tonnes of CO2 produced by Pollok House annually equates to the same amount of emissions as around 10 cars on the road in the UK each year.