Doctoral research into sustainable use of thermal energy from the subsurface

Methods for better planning for Aquifer Thermal Energy Storage systems in cities

On 16 May 2018 at TU Delft, KWR researcher Martin Bloemendal defends his dissertation, ‘The hidden side of cities’, on Aquifer Thermal Energy Storage (ATES) systems. His thesis presents methods for governance, design and planning of ATES systems, which can contribute to better planning in densely built-up areas. The methods would enable the installation of more ATES systems than permitted in current practice, thereby generating greater energy savings. Bloemendal completed his doctoral research while also working on his research projects at KWR and fulfilling his board-membership function at the industry association, BodemenergieNL. Bloemendal’s thesis supervisor is Prof. T.N. Olsthoorn.

Greater sustainability with thermal energy

Aquifer Thermal Energy Storage (ATES) systems provide sustainable heating and cooling for buildings. Making energy supply more sustainable means, among others, that in the future many buildings in moderate climates will depend on thermal energy. Because subsurface space is limited, it is important that its full potential be exploited sustainably for thermal energy storage and recovery. Among other things, this requires a smart approach to the trade-off that exists between the performance of individual systems and the increased energy savings generated by a larger area in which more systems are, or can be, accommodated.

Governance, design and planning

In his dissertation, ‘The hidden side of cities’, Bloemendal presents methods for governance, design and planning of ATES systems. To determine where on the planet these methods could be applied, the dissertation includes a map of the world which identifies areas where, on the basis of subsurface and climate data, ATES systems could be installed. The results show that for urban areas in North America, Europe and East Asia a better planning and design of ATES systems can ensure the optimal use of the subsurface for thermal energy, and thereby the generation of greater energy savings.

Sources of heath and cold in a city, impression (by Anne de Groot, cover dissertation).


Global ATES suitability map. Green: climate and geohydrology are suitable, urban areas in those areas are hot-spots for ATES. Red color: geohydrology and/or climate are unsuitable. Yellow: medium suitability. In cities with suitable climate but medium geohydrology suitability, the pressure for ATES on subsurface space will be largest, those urban areas are indicated in the scarcity markers.


Dr.Martin Bloemendal (right) is handed the doctoral degree by his supervisor at TUD, Prof. Theo Olsthoorn. Left (without beret) is KWR colleague and one of the external examiners, Niels Hartog.