The role of heat probes in the energy transition: Authorisation procedures and potential

Briefing

The energy transition poses major challenges for the real estate sector particularly surrounding heat supply. Fossil fuels such as oil and gas are increasingly being replaced by sustainable alternatives to achieve climate targets and reduce costs in the long term. One particularly promising technology is the utilisation of geothermal energy using heat probes. This enables an environmentally friendly, efficient and virtually CO₂-free heat supply for buildings. However, before a heat probe can be utilised, an approval process is required, which can vary in complexity depending on the location and depth of the borehole.

This article is intended to provide an initial overview of the authorisation procedures that may be required:

1. Location analysis

The first step is to analyse the site involving a technical and legal check on whether the planned site is suitable for a heat probe. Important factors are

Geological conditions: The subsoil must be stable enough to allow drilling.
Water protection areas: In sensitive areas such as drinking water protection zones, strict conditions and even bans apply.
Distances to neighbouring properties: Minimum distances must be maintained to avoid conflicts.

In this phase, a technical expert should first be consulted to assess the geological and hydrological conditions. If the project is located in a water protection area, a legal assessment of the site would also be required.

2. Making the application

If the site analysis is positive overall, the application is submitted to the competent authority which is normally the local nature conservation authority. in some federal states, a mining permit is also required for drilling below a certain depth (e.g. 100 metres), meaning that the mining authority may be responsible for the application. The application must contain detailed information:

Technical data on the borehole (depth, diameter).
Details of the planned heat pump system.
Proof of environmental compatibility (e.g. in particular for the protection of groundwater).

3. Official inspection

The authority examines the application for technical and ecological feasibility. The following aspects are considered:

Groundwater protection: It must be ensured that no contamination of the groundwater occurs.
Safety aspects: The stability of the subsoil must not be jeopardised by the drilling.
Compliance with the requirements of the Federal Water Act (WHG) as well as regulations applicable in the federal state.

Depending on the complexity of the project, this step can take several weeks to months.

4. (Drilling) authorisation and implementation

After a successful inspection, the authority issues a licence, which may be subject to conditions (e.g. regular leak tests). The borehole can then be drilled by a certified specialist company. During the work, regular monitoring is carried out by the authorities to ensure that all requirements are met.

5. commissioning and documentation

Once the drilling work has been completed, the heat probe is installed and connected to the heating system. Commissioning must be documented and reported to the authorities. In addition, the authorities generally oblige project developers to carry out regular maintenance to ensure safe operation in the long term.

Why does this process make sense?

Although the approval process can involve a certain amount of effort, it is worth it: those who hold such sustainable real estate in their portfolio benefit from low operating costs in the long term, an increase in property value and an important contribution to the energy transition. The energy efficiency of properties plays a central role in the environmental aspect (E) of the ESG criteria. A high ESG score can, for example, improve creditworthiness and make it much easier to finance projects. Non-sustainable buildings, on the other hand, lose value (so-called “brown discounts”) and are also more difficult to market.