Updated: Aug 25, 2022
Assuming you’re familiar with the constant despondent news forecast for rising energy prices within the home, along with climate change, the focus on shifting to alternative green energy solutions has never been so prevalent. Recently within our work, I have come across a growing number schemes which aim to incorporate renewable energy solutions within historic and listed buildings. As this trend in construction is forecast to continue to grow, we hope that this brief and simple introduction can help shed some light on the matter.
The most common form of introducing solar power to the home is through large solar panels mounted atop the roofs of historic buildings. However, within listed and historic non-designated structures, introducing large solar panels are so obtrusive that they often detract from the character and therefore, result in a level of harm to the significance of the historic building, which could have the potential to be an issue when seeking listed building consent and/or planning permission. Therefore, ensuring that a scheme employs an appropriate number of solar panels that are thoughtfully and sensitively positioned atop the building is essential.
Alternatively, PV Slates/Tiles are becoming increasingly prevalent within schemes that wish to introduce Solar Power within historic buildings. PV slates (photovoltaic roof tiles) are a more seamless approach of integrating solar technology within a building, an aesthetic that is achieved by replacing the roof tiles. PV Tiles can also be integrated into glazing and can be used on the glass roof of conservatories where there is a good incline to the sun. Although a visually more appeasing option, the removal of roof tiles has the potential to interrupt and denude potential historic fabric, so the installation, location and massing of these tiles should be appropriate to the heritage asset in order to comply with the associated policy and guidance.
Wind power, in many domestic properties, is utilised within small wind-turbines that can be roof-mounted or stand-alone, all of which convert kinetic energy into electrical energy. Incorporating wind-turbines to a listed building or within the grounds of one will inevitably incur heritage issues due to their conspicuous presence. Should the proposed wind-turbine have the potential to detract from the physical fabric of a listed building, its setting, or even the local historic environment, you are likely to face issues within the planning and/or listed building consent applications. As such, it is recommended that these structures should be placed in a location where they will not impede upon views to or from relevant heritage assets, and therefore will be less likely to impact upon the significance of the property.
Heat pumps are devices that heat a building by transferring external thermal energy using the refrigeration cycle. Many heat pumps can also operate in the reverse direction, cooling the building by removing heat from the enclosed space and rejecting it outside. Options for these include: ground source, air source, and water source. The first option for installing a heat pump into a property is a ground source heat pump which works by transferring heat from the ground outside of your home to heat your radiators, stored water and underfloor heating. Incorporating ground source heat pumps within a historic building will inevitably incur heritage issues due to the nature of the work involved within their installation process and the modification required within the building.
The excavation of those areas surrounding historic buildings, required to install the heat pump, also has the potential to disturb potential subsurface archaeology, which often is initially identified through historic mapping and/LiDAR imagery. Further, the installation of the pump device onto the side of the building has the potential to remove historic fabric and detract from the character of the property if not located within a suitable position. Therefore, it is vital that the location of the heat pump within the grounds of the house and the trench created for the buried pipes is carefully considered and researched in order to minimise any potential heritage complications.
The second option for installing a heat pump into a property is an air source heat pump which works by taking heat from the air outside and converting it into energy to heat the home. As with the ground source heat pump, incorporating an air source heat pump to a historic building has the potential to impact targeted areas of historic fabric and the overall character of the building depending on where it is attached. Consequently, it is fundamental that great consideration goes into the location of the heat pump on the building.
Water source heat pumps are also an option but as not every property has access to a suitable water source, we have focused on ground and air.
Policy & Guidance
Currently, Historic England’s guidance emphasises ‘balancing the benefits and costs’, stating that they would support a scheme which:
‘Acknowledges the need for society to invest in a wide range of renewable energy generation technologies;
Recognises the potential environmental impacts of different technologies, including their implications for the historic environment;
Keeps the balance of environmental benefits and disadvantages of each technology under continual review; and
Continually seeks to limit and mitigate adverse impacts’
Further, Historic England also requires that the assessment of the balance between harm and benefit should be done on a case-by-case basis and should be informed by: evidence, formal assessment, relevant policy and guidance.
In relation to the development to heritage assets the National Planning Policy Framework (MHCLG 2021) outlines:
‘When considering the impact of a proposed development on the significance of a designated heritage asset, great weight should be given to the asset’s conservation’ (199) As such ‘Any harm to, or loss of, the significance of a designated heritage asset, should require clear and convincing justification.’ (200).'
Therefore, it is vital that any newly introduced renewable energy sources do not cause harm to the heritage asset, and often (in my experience) the perceived benefits of introducing green energy solutions will not be enough to solely outweigh the potential harm if they not approached and applied correctly.
Local Planning Authority (LPA) Policy
Depending upon the area in which you are situated, your local council will have a ‘Local Plan’, most of which have their own specific policies and guidance relating to the development of listed buildings and heritage assets. For that reason, any proposed development or newly introduced renewable energy solutions will need to gain Listed Building Consent often alongside planning permission.
In order to protect our historic environment, it is vital that we can source and employ renewable energy solutions to reduce fuel consumption and increase energy efficiency. However, it must be recognised that the introduction of such new technology within heritage assets has the potential to cause damage to our finite heritage resource. As such, it is essential that the new incorporation of such technologies is considerate of the surrounding historic environment.
At Blue Willow Heritage, we provide expert advice and management strategies to ensure that we can allow for the implementation of renewable energy within historic buildings without compromising their assessed significances. If you need help managing your heritage assets, Blue Willow Heritage can help. If you would like to discuss your project or simply need some impartial, no-obligation advice, then please do not hesitate to get in touch.