News  |  Success Factors and Lessons Learned: Seven Years of Developing the Delft Heat Network and Geothermie Delft at EBN's Heat Transition Day

Success Factors and Lessons Learned: Seven Years of Developing the Delft Heat Network and Geothermie Delft at EBN's Heat Transition Day


11 December 2025

On 4 December 2025, during the 'Heat Transition Day' (Dag van de Warmtetransitie) organised by Energie Beheer Nederland (EBN), Rass Butt and Eric Haardt, the directors of Geothermie Delft B.V., discussed the success factors and lessons learned from the Geothermie Delft project. As we approach the completion of construction and the start of heat delivery, we share our most vital insights.

The realisation of Geothermie Delft and the Delft Heat Network — a new thermal grid serving 6,000 housing association homes — offers crucial insights for municipalities, energy companies, and project partners working on the energy transition. Seven years of development have highlighted clear success factors and learning points that provide a roadmap for future projects.

Success Factors

  1. A strong and vital coalition The project brought numerous parties together, each with their own interests but united by a shared ambition. A well-functioning partnership, built on trust and transparency, proved essential.
  2. Transparency and an integrated business case Clear financial principles and interim decision-making allowed partners to manage risks and investments effectively. The integrated business case provided shared insight and collective responsibility.
  3. Independent process management Heat network directors with technical expertise steered the project’s quality, progress, and decision-making. This was crucial for navigating the process from 'broad concept to fine detail' and making complex choices at the right moments.
  4. Starting with heat demand The requirements of the housing associations were central. This allowed for a clear focus on affordability for tenants — a vital prerequisite for public and social support.

Lessons Learned

  1. Mismatches in subsidies and permitting processes In practice, subsidies, loans, and permits are not always available at the exact moment investment decisions must be made. This can lead to project delays, despite the high sense of urgency.
  2. Avoiding 'chicken-and-egg' scenarios The source and the network are highly interdependent. Without certainty regarding the network, it is difficult to develop the source, and vice versa. A clear administrative and leadership role for the municipality can help break this cycle.
  3. The role of the local authority The Municipality of Delft facilitated the process and safeguarded the public interest without being a direct part of the heat supply chain. A conscious and clear division of roles is crucial here.
  4. Building an expandable backbone A future-proof heat network provides the necessary capacity for growth and the connection of additional homes and heat sources.

Working together on sustainable heat

The lessons from Geothermie Delft and the Delft Heat Network help us better prepare for the next steps in the energy transition. Together with our regional partners, we continue to work towards providing reliable, sustainable, and affordable heat for residents.

 

Tags
insights
2026 © Knijnenburg Producties