Exeter Energy is insisting that publicly-owned greenfield land in Riverside Valley Park is the only viable site for a heat network plant it is proposing to build while failing to explain why it has rejected brownfield alternatives in nearby Marsh Barton industrial estate.
The Leeds-based company, which is controlled by 1Energy Group and Asper Investment Management, applied to the city council in December for outline planning permission to construct the energy plant in Grace Road Fields, a fifteen acre public open space in the valley park.
Despite previously presenting a River Exe-powered water source heat pump as essential to the project, the company’s planning application said the plant’s “primary source of heat generation” would be air source heat pumps and did not mention a River Exe water source connection.
The plant is intended to power an underground district heating network which is due to receive £42.5 million from the government Green Heat Network Fund. When the government announced the funding it said the network would use “the UK’s largest high-temperature water source heat pump”, a claim repeated by its investment scheme delivery partner and the city council.
However a Green Heat Network Fund spokesperson has now confirmed that the government grant “is not conditional on the inclusion of a River Exeter water source heat pump” and that the project was awarded funding for its initial phase alone, including only air source heat pump installation.
The spokesperson also confirmed that the prospective use of waste heat from Marsh Barton incinerator and an on-site data centre, also repeatedly promoted by Exeter Energy, are only “potential” connections that might take place in later project development phases.
The Department for Energy Security and Net Zero, which is behind the scheme, failed to respond to questions about the contradictions between its claims and the company’s published plans.
Exeter Energy Network delivery timetable. Source: Exeter City Council.
Three weeks ago 1Energy presented city councillors with a project update confirming that it intended to rely on air source heat pumps, alongside gas boilers, in the first phase of the project.
It also said it expected the city council to grant it planning consent to build in Grace Road Fields next spring, at the same time as selling it the Riverside Valley Park site, shortly before collecting the bulk of the government grant.
Its presentation was otherwise vague about the delivery the first phase of the project, which it said would be completed in “years 1-2”, and exactly what it might deliver in later phases.
We asked the company a series of questions about delivery timing and content. It confirmed that the project’s first phase, depending solely on air source heat pump technology and gas boilers, will be complete by the end of 2029. It’s this that the government grant is supporting.
It also confirmed that gas boilers are expected to provide a quarter of a total of 8MW of network heat supplied in each of these two first phase years.
Exeter Energy heat plant indicative elevations. Source: Exeter City Council.
The project’s second phase is intended to take place from 2030 to 2035, when the company’s presentation said that a “significant waste heat source” would be “available” from the adjacent Marsh Barton incinerator. The incinerator contract expires in 2044, after which it will become redundant because of its colossal carbon emissions.
We asked the company to explain the rationale for a connection in such circumstances. Its answer wasn’t very convincing. It said the “timing of the connection to the Viridor plant is dependent on a number of approvals and a contract being agreed with the operator.
“Construction work to connect to the Energy from Waste [incinerator] facility will also need to take place during the plant’s scheduled shut downs and we believe a connection is possible in 2030, subject to agreeing the contract and the construction timetable.”
Its presentation also mentioned the possibility of extracting waste heat from an on-site data centre sometime before 2035. We asked the company to provide examples of data centres elsewhere in the UK that are located in flood zone three, like Grace Road Fields. It said it could not, as it did not have “the necessary information” to do so.
Exeter Energy heat plant indicative elevation. Source: Exeter City Council.
The company presented the third phase of the project as beginning in 2036, when it said “significant amounts of latent heat” would be “available” from the River Exe – or Exeter Ship Canal, previously not mentioned as a potential heat source in project promotional materials.
Electric and hydrogen boilers, and geothermal and solar thermal technology, were all also presented as potential future heat plant energy sources, providing five third phase options altogether.
We asked whether the inclusion of of a River Exe water source heat pump as part of the Exeter Energy Network heat source mix is a certainty, or whether is it now being treated as an option. Instead of answering the question, the company said such a pump would have the “potential” to act as a stable low carbon heat source, but would require “a number of licences and approvals”.
We asked again. Second time around all it would say was, were the heat network to grow, what was certain was that it would need additional sources of heat. It added that a water source heat pump would be its “preferred technology” in such circumstances – subject to “completing the consenting and licensing process with the relevant bodies”. So that’s definitely a maybe.
Grace Road Fields last weekend
The company’s 37-page project update presentation hardly mentioned Grace Road Fields. It did claim that it wants to buy and build there because, among other things, the incinerator and the river are nearby. It also cites proximity to the council solar array in Water Lane.
We pointed out that this 1.2MW photovoltaic array is capable, in optimal conditions which are the inverse of the conditions in which the greatest demand for space heating occurs, of producing less than a quarter of the proposed heat plant’s electricity needs – and that it is already in use.
We asked in what ways the array is relevant to the Exeter Energy Network project. We were told that, although it “will not provide all the electricity required to meet the electricity demand of the energy centre”, it “can provide some of the electricity supply”.
The company didn’t say how much, although we might allow that it could connect to the council solar array to, say, power its emergency lighting, at least during summer months.
However, if we also allow that the extraction of waste heat from the incinerator could become financially viable for a few years before decommissioning, and even allow that a River Exe water source heat connection might one day be made, none of these possibilities explain why the company can only construct its heat plant in Grace Road Fields, as it claims.
We asked how many potential heat plant sites in nearby Marsh Barton industrial estate had been considered, on what specific grounds they had been rejected and, in particular, whether the vehicle storage pound in Grace Road Central had been considered, just a stone’s throw away. We also asked why it hadn’t been considered, if not, and on what specific grounds had it been rejected, if so.
The company again failed to answer our questions. It said: “Other sites were investigated adjacent to the river but were excluded for other reasons including size and proximity to residential properties”.
When we asked again, inviting the company to make its position clear, we got a different, no less inadequate, response: “Siting the energy centre in the Marsh Barton industrial estate would involve very significant engineering challenges, and associated costs”.
It did not explain what these engineering challenges would be, nor why they seem insurmountable to a company that plans to lay thirteen miles of heat distribution pipework across the River Exe valley floor then along its length, as well as through the city centre.
Nor did it explain why they would be so much more expensive to address than any other aspect of what is says is a £120 million project.
Illustrative Exeter Energy district heating network map. Image: Exeter Energy.
Perhaps the company thinks the public have no right to know why it wants to build in Riverside Valley Park even though it is the public whose Grace Road Fields access rights it wants to remove?
In any case, members of the public certainly don’t endorse the company’s plans, and their objections are being reinforced by challenges submitted by statutory consultees.
Devon Wildlife Trust, with which the company claims to have had “positive engagement”, has objected on the grounds that the proposals “do not provide sufficient evidence to satisfy the requirements relating to biodiversity” in the National Planning Policy Framework (NPPF) and have not addressed the requirements of the Environment Act 2021.
It also says that “a range of protected species have been identified as using the site” and that the scheme “should recognise and respond to the importance of the Riverside Valley Park landscape which represents a critical wildlife-rich resource”.
Adding that wildlife surveys accompanying the plans are “insufficient” and the provided biodiversity assessment is “unuseable”, the charity also points out that the company has not followed through on the commitment to biodiversity it claimed in private.
The Environment Agency, with which the company also claims to have had “positive engagement”, appears similarly unconvinced. Its objection also says that the plans do not comply with NPPF, posing “an unacceptable risk to the environment”, because “insufficient information has been submitted to demonstrate that the proposed development will be safe from flooding over its lifetime”.
It points out that “there is no safe access and egress route for the site”, which is at risk of 36 hour floods, and that “if any issues with the utilities were to occur, access for maintenance will be impossible during this period”, adding that “further consideration needs to be given to the impact of this on customers of the heat exchange system”.
It also points out that the plans must pass the NPPF flood risk sequential test, which seeks to ensure that development does not take place in flood risk areas if there are “reasonably available alternative sites, appropriate for the proposed development, in areas with a lower risk of flooding”.
The city council, as planning authority, is required to ensure that developers have considered all other “reasonably available” sites under this regime. But, as the Environment Agency points out, Exeter Energy has apparently not provided any details about the alternative sites it has considered, which must be comparatively assessed for flood, and other, risks before planning approval is granted.
The Environment Agency adds, drily: “We highlight that the submitted application is for an ‘air source’ heat exchange, while the sequential test document refers to a ‘water source’ heat exchange”.
Referring to NPPF flood risk vulnerability classification definitions, it questions whether an air source heat pump-powered plant constitutes “essential utility infrastructure which has to be located in a flood risk area for operational reasons”.
(As council planning committee chair Paul Knott never tires of reminding committee members, planning decisions can only be based on the information applications contain. So the council cannot approve Exeter Energy’s application on the basis of its vague future development plans.)
As if to put Exeter Energy on notice of this issue, the Environment Agency’s objection also says: “We note that the current proposal does not appear to include any abstraction or discharge to the main river. We wish to make the applicant aware that if this were to change, an abstraction licence and discharge permit may be required for the proposal.
“A permit is separate to and in addition to any planning permission granted. The applicant should not assume that a permit will automatically be forthcoming once planning permission has been granted.”
