‘Are heat networks the way to decarbonise Edinburgh’s heating and make it affordable?’

This was the question posed to a public audience at Saturday’s (28th Jan 2023) event in Edinburgh’s Old Town organised by the community group Transition Edinburgh. The event brought together key experts in the low-carbon heat industry with local politicians, representatives from the council, community group leaders and members of the public that live and work in the capital.

In the U.K., at least 80% of our homes and businesses rely on a central network of pipes to transmit natural gas to boilers. They account for 13% of our greenhouse emissions – together with transport, these are the two major culprits behind climate change. The U.K.’s gas network is a system that has been developed over many decades to become one of the world’s most advanced, centralised heating solutions, matched only by the Netherlands. 39% of Edinburgh’s carbon footprint relates to the use of natural gas use in our homes and buildings (2030 Climate Strategy Delivering a Net Zero, Climate Ready Edinburgh, December 2021, City of Edinburgh Council) and is the single largest reduction that will enable the city to achieve net zero.

The recent draft energy strategy published by the Scottish Government reiterates the need to transform our energy system to address current uncertainties with global market volatility and high energy prices. One way to do this is through “accelerated decarbonisation of domestic industry, transport and heat.”

One option would be to incentivise every building owner to swap out their gas boiler at the end of its life for a greener alternative like a heat pump. Heat pumps are a proven technology that have been in use for many years in far colder places than Scotland. Heat pumps come in different shapes and sizes and can be retrofitted to many different types of buildings. However, solutions that rely on building owners acting independently are inherently inefficient, especially in areas where building densities are high, as this would imply a massive and costly reinforcement of the already overloaded power grid.

Heat networks are an alternative. As a shared resource, they can deliver more heat to more buildings with less power.

Heat networks are a solution that has been widely adopted across many European cities like Copenhagen and Amsterdam over recent decades. Even in Scotland, they already support a large number of homes in Aberdeen and Lerwick. They share similarities with gas networks in their reliance on an underground system of pipes, although, rather than transporting pressured gas, they transport heat in the form of pressurised hot water from multiple points of generation to potentially thousands of homes and businesses.

If you know where to look, you can already find many examples of smaller-scale heat networks across cities like Edinburgh and Glasgow, often developed by ‘early adopters’ like universities. With the emergence of large-scale heat pump solutions like that recently installed at Queens Quay in West Dunbartonshire, we can now extract heat from the ground, rivers and the sea or the air and distribute this widely across a neighbourhood or even a whole city. This type of solution is currently being developed to support new development in the Granton area.

The event was designed to raise awareness of the potential for clusters of heat networks to emerge within ‘hotspot’ locations across the city where heat demand is expected to be greatest. Over time the ambition is for these networks to join up creating a seamless web of underground hot water distribution to the buildings across the city. The audience raised many questions that experts working in this field attempted to answer. Where are these initial zones that will act as breeding grounds for these networks? How much disruption will be caused by their installation? Who will own and run this network? Will my annual heating bills be lower? How will prices be controlled, so monopoly owners are regulated effectively? What will the city look like in 2050 if heat networks are widely adopted?

The audience spoke with one voice that we need to keep decarbonisation as the top priority and accelerate towards solutions that deliver it in Edinburgh.

The concept of district heating was warmly accepted. The participants wanted to hear more about the propositions and to engage more widely with communities and citizens in a dialogue. Communication and consultation was a top priority. The audience also expects that to be facilitated by the City of Edinburgh Council and welcomed private sector involvement in the investment, delivery and operation of district heating systems.

It is still early days to develop heat networks across Scotland’s cities. Despite all the warm words from Holyrood and Westminster, the scale and pace of action remain inadequate to achieve mandated national adoption targets. There is hope within the Scottish Government that Local Authorities will take the lead by creating arms-length energy supply companies that could either develop assets themselves or enter into joint ventures with private sector partners to co-develop this infrastructure. One thing is clear – the Scottish Government has no appetite to fund this transition alone, so private investment is likely to be the only way to fill the huge funding gaps. One model has emerged on the Midlothian edge of Edinburgh’s boundary, where a joint venture between Midlothian Council and Swedish-state owned Vattenfall is progressing a heat network to support much of the new development surrounding the Millerhill incinerator. In the north of the city, the council is soon to consider its options in Granton, where a heat network is destined to provide low-carbon heat to much of the waterfront’s new development.

The City of Edinburgh Council is committed to publishing its new ‘heat network zones’ this year to delineate those areas across the city with the greatest potential for this technology. Suppliers may then be able to bid for the rights to develop each zone and supply customers that fall inside it. The Scottish Government has recently passed a Heat Networks (Scotland) Act 2021 to support the regulation behind their wider adoption. There is considerable momentum building around the potential of heat networks to support affordable, low-carbon heat in Scotland’s larger urban areas enabling consumers to break their direct exposure to the volatility of global energy markets.

Johanna Carrie, coordinator of the Clean Heat Edinburgh group comments: “Attendees at the event acknowledged the need to break away from our universal reliance on unsustainable natural gas for heating. Heat networks are clearly a key technology solution for cities like Edinburgh that can help us do this. To really make progress, it is clear we need to establish a champion for low carbon heat across the city that can communicate a clear vision to communities, businesses and residents. This champion could be at a national or local level. Without such a leader, we are unlikely to produce a heat transition plan that can get the buy-in of the whole city.”

So what’s next? The Clean Heat Transition is already planning the next event, which remains focussed on fostering the open and positive discussion with everybody that wishes to attend, across the industry, the public sector and all members of the local community. If you would like to take part in our next event, please drop a note to our email:


You can view and download the participants’ presentations here