District heating networks and decarbonisation: Video Visit + Discussion

On 8 September Future of London ran its second Video Visit + Discussion, this time on the theme of decarbonising energy. Via video, we ‘visited’ Bunhill 2 Energy Centre in LB Islington. We then discussed the project, and how the borough’s energy strategy is evolving, with Rodrigo Matabuena, LB Islington, Carol Costello, Cullinan Studio and Catarina Marques, London South Bank University.

Above: This was one of several videos about Bunhill 2 Energy Centre that attendees watched before the discussion with our speakers. We recommend you watch it before reading the write-up. Video courtesy of LB Islington. 

Decarbonising LB Islington: the evolution of the Bunhill heat network

In June 2019, the council declared a climate emergency and the borough is aiming to be zero net carbon by 2030. Heat networks are a key element of the borough’s transition away from fossil fuels. “The reach, cost-effectiveness and flexibility of heat networks is huge compared to other decarbonisation options, which makes them one of best ways of decarbonising heat,” said Rodrigo Matabuena, Energy Capital Projects Manager, LB Islington.

The borough first started looking into heat networks in 2005/6 and in 2012 Bunhill Heat and Power began supplying heat and hot water to 800 homes and two leisure centres. In 2015, the borough began to expand the network with Bunhill 2 Energy Centre, which started operating in March 2020. The energy centre and its new pipework added a further 550 homes and a primary school to the existing network.

Above: please explore the interactive map which shows key points on the Bunhill Heat and Power Network. 

Bunhill 2 is the first network in the world to take low-grade heat from the waste heat generated in the Underground and upgrade it to the high temperatures needed to heat local buildings, in a densely populated area. The key benefits of the energy centre, particularly from the council’s point of view, are that it’s tackling fuel poverty (residents connected to the network have cheaper energy bills) whilst reducing carbon emissions.

“But it’s not just about the units of heat we’re delivering and the lower tariffs,” added Rodrigo. “This infrastructure adds value to the borough and puts Islington council at the forefront of the climate change fight.”

Four speakers talking
Clockwise from top left: Sophie Nellis, Future of London; Catarina Marques, London South Bank University; Rodrigo Matabuena, LB Islington; Carol Costello, Cullinan Studio. Source: FoL.

Designing Bunhill 2: infrastructure to be celebrated  

This sentiment was echoed by Carol Costello, Practice Leader, Cullinan Studio: “The Victorians were very good at celebrating engineering and the craft of new railway lines, bridges and pumping stations – they employed craftspeople to celebrate new infrastructure once it was built. This building evokes a sense of pride, not only for Islington but for the UK as a whole.”

Cullinan Studio designed Bunhill 2 Energy Centre, which stands on the site of the former City Road Underground station. The disused station has been transformed to house a huge underground fan which extracts warm air from the Northern line tunnels below. Designing an enclosure around such a complex engineering project was challenging, and the architects worked closely with the engineers from Ramboll and TfL to coordinate all the different components.

Energy centre in London
Bunhill 2 Energy Centre. Source: LB Islington.

The result is a highly striking, three-storey structure. Around the bottom, at street level, is a frieze by Scottish artist Toby Paterson that tells the history of the planning of local estates. And the pattern on the building’s aluminium panels changes towards the top – because of the air flow needed by the mechanical equipment.

Consulting local communities: “Heat is an abstract idea”

City Road is a busy road and major route through London. There are lots of people moving through this area, and lots of new towers being built. But there are also communities who have been there for generations, for whom change to the built environment can be unsettling.

“It was our job to explain what the structure was and what it would look like,” said Carol. “But both heat and how it moves around pipes is kind of an abstract idea. So we held public meetings with the community, using cardboard models and drawings to explain and visualise the project.” These consultation sessions helped build trust and consensus around the project, enriching the design process.

Electric car charging on a street
GreenSCIES will help to facilitate the transition to more electric vehicles. Source: Frank Hebbert on Flikr. (License CC BY 2.0.)

Building on Bunhill 2: Green Smart Community Integrated Energy Systems (GreenSCIES)

Launched in March 2020, GreenSCIES is LB Islington’s latest heat network. An Innovate UK funded project, it aims to deliver low-carbon, affordable energy through a smart local energy network that combines not only heat but also power and transport. It will recover heat from the Underground, like Bunhill 2, but also waste heat from two local data centres.

This heat is then upgraded with heat pumps, to supply heat to the neighbourhood. Local power is going to be generated with solar panels, and low-carbon transport will come in form of electric vehicles. “GreenSCIES represents the evolution of Bunhill 2 because it’s not just a heat network, it’s also about generating local power and facilitating the transition to electric vehicles”, explained Catarina Marques, Research Fellow, London South Bank University and Project Manager of GreenSCIES.

The main benefits for local communities are having access to low-cost, clean energy which is partly generated locally, and seeing improvements to local infrastructure, such as access to more electric vehicle charging points. “But it’s become obvious that the community can also act as strong influencers to make smart, local energy networks a reality,” said Catarina. “We want the local community to co-design GreenSCIES – and early engagement is crucial for achieving that.”

Encouraging people to think about their streets – and their future

Exposed blue water pipes above ground in Dresden
Large blue water pipes running above ground in Dresden, Germany. Source: FoL.

Cullinan Studio has been carrying out the community consultation for GreenSCIES, which has all been online due to the pandemic. One of the barriers to district heat projects is that councils usually dig up the streets to bury the pipes, causing disruption for residents. So Cullinan Studio has been researching what it would be like if some pipes were above ground, in planters or living walls for example.

But this has its downsides: it might reduce parking on some streets, or take up space on what are already quite crowded streets, particularly in a dense borough like Islington. “This project is challenging us to think about what’s most important to us,” said Carol. “Can we think of doing things differently for the sake of the planet?”

As well as its impact on the consultation process, Covid-19 might also end up re-shaping the design and rollout of GreenSCIES. One of outcomes of the pandemic is the call for more people-friendly streets and low-traffic neighbourhoods, and Carol sees this as an opportunity to work with the council to integrate more walkable streets into the delivery of GreenSCIES.

Working across sectors

There’s a large consortium of 15 partners involved in GreenSCIES, including London South Bank University, LB Islington, Cullinan Studio and TfL. The partners bring different, but complimentary, expertise, on, for example: large infrastructure projects, renewable energy, artificial intelligence, transport and new business models. Catarina believes this combination of skills is key to delivering such an ambitious project.

New regulations around heat networks, due to be announced soon, may encourage more private-sector investment in heat and encourage more cross-sector partnerships on heat networks. But when it comes to achieving the net zero ambition, Carol was keen to stress that district heating is just one part of the equation: “We have a huge amount of building stock that is energy inefficient so if we want to reduce demand for heat, we need to improve it,” she said. “This means developers and local authorities working together more collaboratively to find creative ways to retrofit our existing buildings.”

Attendees ask questions during Q&A
Interactive Q&A with attendees. Source FoL.

Challenging but definitely worth the effort

Attendees made a number of interesting points in the Q&A. In response to a question from Nick Blackmore, Inner Circle Consulting, about the lessons other councils could learn from LB Islington, Rodrigo stressed how important it is to get buy-in from both the council and the politicians from the start.

The role of local businesses was also discussed. Camilla Ween, Goldstein Ween Architects, was interested in whether local businesses could not only use energy from the GreenSCIES network to heat their buildings, but also in their businesses’ processes. While this might be possible in the future, Rodrigo explained that, at the moment, converting energy isn’t the aim of GreenSCIES. “Upgrading heat so it can be used for industrial processes rather than domestic uses would be a bit of a challenge,” he added.

But engaging with commercial properties is part of the ongoing community consultation. And GreenSCIES is working with the council to connect not only the council’s estate buildings but also as many commercial buildings as possible.

The Q&A also raised some of the key challenges to developing heat networks, including the large capital investment required and the disruption caused by laying pipes in dense neighbourhoods. “But the decarbonisation of heat is key to achieving our net zero targets so even with all these challenges, heat networks are definitely worth the effort and investment,” stressed Catarina.

Watch all of the Video Visit + Discussion by clicking on the YouTube video above.

If you’d like to get involved with our Achieving Net Zero programme, get in touch with Anna Odedun, Head of Knowledge. And if you’d like to join us on 26–30 October for our first digital conference on Achieving Net Zero, register your interest here.