Positive Heat District Project on aquathermal energy

Project idea: De-risking investment in multi-source district heating for Positive Energy Districts

Challenge. Rolling out district heating at PED scale requires investments of tens to hundreds of millions of euros, made under significant uncertainty: which renewable source (or combination — aquathermal, geothermal, waste heat, ATES) offers the best value on a given site, and how does that choice cascade into network topology, pipe sizing, phasing and ultimately the business case? Today, these decisions are typically made sequentially, using rule-of-thumb sizing and conservative safety margins — leading to overdimensioned, more expensive networks and heat prices that are hard to defend to end-users, financiers and local authorities. This is a key bottleneck slowing down the replication of affordable, flexible, integrated energy systems across European cities.

Proposed approach. This project would develop and demonstrate an integrated methodology and toolset that jointly optimises source strategy and network design for multi-source district heating, instead of treating them as separate engineering steps. This combines two elements that are rarely brought together:

1. Dynamic renewable source characterisation, using 3D digital-twin simulation of surface water bodies to determine real (not rule-of-thumb) aquathermal potential — thermal impact zones, regeneration, seasonal variation — in combination with other local sources (geothermal, ATES, waste heat).

2. Joint techno-economic and thermo-hydraulic network optimisation, simultaneously solving for source mix, plant sizing and siting, pipe routing and diameters, thermal buffer placement, heat-exchanger vs. booster-heat-pump strategy, and phased rollout — optimised directly against NPV/LCOH over the network's lifetime, with hydraulic feasibility guaranteed rather than assumed.

The methodology would be validated and refined across multiple demonstration sites in different countries, testing its transferability across urban contexts, water-body types, climate zones, and regulatory/permitting regimes — a core rationale for a transnational consortium.

Expected outputs and impact.

• An open, transferable methodology (and supporting toolchain) for source-network co-optimisation, usable by cities, utilities and energy communities beyond the pilot sites.

• Demonstrated reduction in overdimensioning and investment risk versus conventional sequential design approaches, quantified across real case studies.

• Decision-support material (scenario comparisons, sensitivity analyses, permitting pathways) that strengthens the business case cities and utilities need to secure financing and public buy-in for PED heat infrastructure.

• Contribution to EU goals on affordable, flexible, integrated local energy systems (SET Plan, EU Mission on Climate-neutral and Smart Cities).

What we bring to a consortium. Proven track record delivering aquathermal feasibility studies and multi-source district heating business cases for hospitals, municipalities, provinces, energy cooperatives and heat utilities (Belgium, Netherlands), including a proprietary 3D digital-twin methodology for source potential and an optimisation tool for integrated network design. We are well positioned to lead the technical work package(s) on source characterisation and network optimisation, and to contribute real demonstration sites and reference cases to the consortium.

Looking for: municipalities/urban authorities with a candidate PED site and district-heating ambitions; research partners with complementary expertise (e.g. energy communities, flexibility/demand-side management, digital twins for other domains, socio-economic evaluation); and/or utilities or industry partners interested in piloting the methodology.