Today more than ever we are facing two big challenges: the rising cost of living and climate change. In this article Andy Wilkinson, CEO of WilSon Energy shows how district and community heat networks can help both reduce carbon emissions and cut costs.
Home heating and hot water account for about 20% of UK greenhouse gas emissions. To reduce this, we will have to switch to heating our homes with electricity from non-fossil fuel sources such as wind, solar and nuclear. But electricity is much more expensive than gas, so just swapping to electric is not an option for hard-pressed householders.
Increasing energy efficiency
Heat pumps reduce the cost of heating water with electricity. Heat pumps use latent heat from the environment to significantly reduce the amount of electricity required to generate a given amount of hot water. Government has recognised this and is incentivising the use of air-source heat pumps by grants to individual householders.
Air source heat pumps, while helpful, are much less efficient than water source or ground source heat pumps, which typically offer twice the electricity savings of air source heat pumps.
Installing ground- or water-source heat pumps though is more costly and also requires access to land or water resources such as rivers or reservoirs, so it does not usually work well for an individual urban home. But where multiple homes can be linked to the same infrastructure, unit costs fall rapidly, and access to a shared green space or nearby water source can often be made easy.
In addition, sharing heat production among multiple homes is more efficient, because not everyone uses the heating at the same time – a “diversity factor” that can reduce power consumption by 30% or more.
A 2016 study by Government showed that properly designed community heat networks can reduce carbon emissions by 80% or more when compared with gas.
Weighing up the costs
Cost wise though the story is more complex. In the 2016 study it was found that even efficient deployments resulted in a 35% higher cost of heating from community heat pumps vs gas, after the cost of the heat pump infrastructure is included.
But in the last year the equation has changed dramatically, with gas prices increasing significantly faster than electricity costs, so that efficient heat pumps now cost a lot less than gas to run day-to-day. If the situation continues, community heat networks based on ground or water-source heat pumps will soon be cheaper overall, as well as greener than the gas alternative.
Also, as the market becomes more competitive, we are seeing the cost of heat pump technology fall, and this will tilt the balance further towards a big growth in heat networks based on ground or water source heat pumps.
Practical implementation
Heat pumps operate at lower temperatures than traditional heating systems. So, for heat pumps the lower the temperature the higher the efficiency. Certain Heating Interface Units (HIUs) can operate poorly when working with a heat pump as they are not designed to operate at lower temperatures, which results in higher flow rates and smaller temperature differentials. This brings down the overall efficiency of a scheme, generates higher carbon emissions and could cost consumers more money. Whilst losses may be relatively small on an individual HIU basis, across an entire residential scheme these issues can cost potentially thousands of pounds in inefficiencies each year.”
Some of our HIU’s have been developed with the next generation of district heat networks in mind and specifically to operate with heat pump technologies.
Drawing on external expertise
Community or “District” heat networks have long been standard in the colder parts of Europe, and at WilSon energy have we worked for over 10 years in implementing and managing heat distribution within communities here in the UK. We install and maintain an HIU in each home, to draw heat from the network to provide domestic hot water and heat the radiators, and we monitor heat usage by residents, billing them per unit used.
Residents can monitor their usage in real time via an ENE3 compliant In-Home Energy Display or over the internet, and we offer a prepay system where this is more appropriate. While the market remains relatively small in the UK, it is growing rapidly. Government is increasing regulation of heat networks, which we very much welcome. So, we think Britain is ready for the large -scale introduction of shared heating.
Government intervention needed
We at WilSon energy believe the Government has a key role to play in encouraging the development of community heating systems based on shared heat pumps. I recently wrote to Kwasi Kwarteng, Minister for Secretary of State at the Department of Business, Energy and Industrial Strategy and suggested that:
Positive progress
In addition to this we are delighted to see that the Government’s Energy Security Bill, which will include powers to regulate heat networks, was introduced in Parliament on 6th July 2022. This is the first step to providing proper consumer protection for all heat network consumers.
I believe that if these suggestions are taken up, we will be well on our way to a cheaper, greener future!”
For more information on WilSon Energy’s integrated heating and billing solutions for Heat Network and District Heating schemes, visit: https://wilsonenergy.co.uk.
