Retrofitting the Past: The Emergence of Ground Source Heat Pumps in Historic Country Homes
Ed Levien, Commercial Director at isoenergy
Ed Levien, Commercial Director at isoenergy joined our “Strategic Energy Decision Making in Historic Country Houses” seminar to help the attendees understand and explore whether heat pumps are an alternative to fossil fuels. Ed went on to explain “If you’re sitting in a house with an oil or LPG or gas board at the moment, or you’re about to build a new house, what can you do and what assets do you have on your land that you might be able to use to get there?”
In our era of mounting environmental concern, renewable energy sources are rapidly gaining ground as a potent solution to reducing carbon emissions. Historic country houses, often seen as bastions of the past, are embracing modernity with green energy strategies, particularly the use of ground source heat pumps (GSHPs). However, this transition comes with its own set of challenges and considerations.
Ed shared a snapshot of properties that are heated purely by ground source by a ground heat pump to help dispel the myth that heat pumps aren’t suitable for old houses.
He went on to comment that a well-designed ground source heat pump connected to a good distribution system can be made to work. It’s all about good design. Followed by good product specification and then good installation. So heat pumps can work in old houses, but not say in all houses as they are at the moment. The benefits of this strategy are tangible, with the potential to significantly reduce running costs and carbon footprint, but it also requires careful forward planning.
As Levien notes, “If you’re thinking about a project, think ahead so you can future-proof the building.” Future-proofing is the process of planning and designing in ways that will prevent future obsolescence and allow the building to adapt and evolve with changing energy needs and technologies.
Renewable energy adoption is not without its hurdles. The high costs associated with the initial installation may deter some. Moreover, electricity – the backbone of renewable systems like heat pumps – is expensive. Levine explains, “Electricity is the most expensive fuel you can buy to heat anything on direct electric, so it might be cheap to put in, but it’s currently more expensive to run.”
Ed continued “The government has signalled electrification of heat is where the UK is heading. So how do we get on that pathway? How do we help you? There is an industry here that needs to grow to meet the future demand, so the future is electric and you need to be thinking ahead.
What am I doing now and what should I be doing now and how can I protect myself now so I can do something in the future? So if you can’t afford to do things now, how can you futureproof the building to be able to do it in phase two or wherever that might come?”
The graph below shows that with the ground source of air source depending on the input costs you can protect yourselves against ongoing running costs.
Ed went on to explore the benefits of a heat pump outside of the cost implications. He explained “Much like underfloor heating, low and slow gets the whole building up to temperature. Use the thermal mass of the building and keep the building at whatever temperature you like to live in. We find that a lot of people moving from timed heating to continuous heating will often end up turning the thermostat down as you achieve a constant temperature, which is an instant energy saving. turning the thermostat down by three degrees because the constant level they get rather than hot spot cold spot, hot spot, cold spot is two or three degrees lower when the thermostat might be set.”
He continued “The other big benefit is the carbon reductions. Against oil, that carbon saving is about 84% directly. So from day one, you change over from oil to a heat pump you will be saving 84% in your carbon output against mains gas. As the grid gets greener the gap is only going to increase, making it a suitable solution for commercial buildings and those wanting a quick way to reduce their carbon footprint.”
The next big issue Ed discussed was around futureproofing a building and planning now so you know what you are doing when your current boiler needs replacing. He also shared some considerations when looking at renewable energy and shared the importance of sufficient insulation to prevent heat loss.
The advent of renewable technologies necessitates a rethinking of infrastructure, underlined by Levine’s emphasis on ‘joined-up thinking’. It’s not merely about implementing renewable technology, but considering how these technologies integrate with existing building layouts. This begins with insulation, the first step to reducing energy consumption. As Levine succinctly puts it, “The best thing you should do first is insulate your building. This will reduce the amount of heat you have to put in and will cut your running costs straight away. Remember that the cheapest unit of heat is the one you hold onto through building fabric insulation.”.
A joined-up approach between the plant room and distribution throughout the building is imperative. He reiterated the importance of ensuring the provision of radiators was designed for maximum efficiency and heat output throughout the building as well as the importance of preventing heat loss with insulation and double or triple glazing.
There are three types of heat pump available:
- Air source
- Ground source
- Water source
Heat pumps work by taking energy from the natural environment, mostly from solar energy either in the air or stored in the ground. This energy is then used to provide heat and hot water in your house. They run on electricity and operate with exceptional efficiency, producing 3 to 4 units of heat for every kilowatt of electricity consumed.
Ed concluded with the following summary:
- All buildings can benefit from renewable energy – but careful design is essential.
- Think carefully about distribution and plant requirements.
- The higher the energy requirements – pool, electric car charging, outbuildings, large house – the greater the long-term benefits.
- Energy bills in buildings are often a significant long-term expense – expect a renewable energy system to reduce these by 15-75%.
- Installing a heat pump in a new build/renovation project is going to cost far less than having to do so retrospectively in a few years.
- Futureproof, save money and reduce the building’s carbon emissions by 60%+.
In conclusion, while the initial costs and retrofitting challenges may seem daunting, the adoption of renewable energy, particularly through GSHPs in historic country homes, is a strategic decision that promises significant long-term benefits. Reduced running costs, lower carbon footprints, and an alignment with future trends make this transition a viable, sustainable choice. The successful integration of these systems hinges on careful planning and design, as well as building insulation. The road to sustainable country houses may be complex, but it is certainly achievable.
Mouldings have developed relationships with specialist consultants and contractors alike to ensure that our projects benefit from a well-considered strategy and installation. The use of an alternative energy sources is becoming prevalent in many of our projects with the common aim of reducing the demand and cost of fossil fuels. Heat pumps, ground loops, bore holes, solar and PV cells are becoming familiar additions to the service installations of a new or refurbished property. So too are the use of grey water recycling and green roof coverings.