TITLE:
Groundwater Utilisation for Energy Production in the Nordic Environment: An Energy Simulation and Hydrogeological Modelling Approach
AUTHORS:
Teppo Arola, Jarkko Okkonen, Juha Jokisalo
KEYWORDS:
Groundwater Energy, Building Energy Simulation, Numerical Modelling, Cold Region, Finland
JOURNAL NAME:
Journal of Water Resource and Protection,
Vol.8 No.6,
May
27,
2016
ABSTRACT: Groundwater
provides one option to utilise renewable energy sources. The long-term
groundwater energy potential for three building complexes, situated at latitude
of 64°, was investigated by combining an energy demand simulation for the
buildings with hydrogeological modelling. First, a reference year for the
building energy demand was created. Secondly, groundwater flow requirements
were calculated. The results of the previous stages were utilised in
groundwater heat transport modelling in an environment where the natural
temperature of groundwater was 4.9°C. Finally, the long-term (50 years)
groundwater energy potential was calculated. The groundwater maintained its
heating potential during 50 years of operation. When both heating and cooling
power were demanded, the long-term pumping rate of groundwater decreased by 60,000
m3/a. Energy utilisation created a cold groundwater plume
downstream, in which the temperature decreased by 1 to 2.5°C within a distance
of 300 m from the site. Groundwater can provide a long-term energy source for
large building complexes in the Nordic climate. Results indicate that
groundwater could effectively be utilised until the temperature reaches
approximately 4°C. Accurate information on the building energy demand and
hydrogeology is essential for successful operation.