Correlation between temperatures of air, heat carrier liquid and seabed sediment in renewable low energy network

A. Mäkiranta*, J.B. Martinkauppi and E. Hiltunen

University of Vaasa, Faculty of Technology, Electrical Engineering and Energy Technology, P.O. Box 700, FI-65101 Vaasa, Finland
*Correspondence: anne.makiranta@uva.fi

Abstract:

The low energy network based on renewable seabed sediment heat has been monitored for several years in Vaasa, Finland. In this study the temperatures of air, heat carrier fluid and seabed sediment are compared to each other and correlations between them are investigated. In this study data from one year 2014, was used. Correlations between these subjects clearly exist. The sizing of installed network seems to be correct; no overuse was detected.

Key words:

Seasonal temperature variation in heat collection liquid used in renewable, carbon-free heat production from urban and rural water areas

E. Hiltunen, J.B. Martinkauppi*, A. Mäkiranta, J. Rinta-Luoma and T. Syrjälä

University of Vaasa, Faculty of Technology, Electrical Engineering and Energy Technology, Wolffintie 34, FI65200 Vaasa, Finland *Correspondence: Birgitta.Martinkauppi@uva.fi

Abstract:

A renewable energy source called sediment energy is based on heat collection with tubes similar to those used in ground energy and is installed inside a sediment layer under water body. In this paper, an investigation of temperature behaviour of heat carrier liquid is made during several years to evaluate utilization of sediment energy. This is done by evaluating temperature variations of heat carrier liquid and its correlation to air temperature. This increases advancement of knowledge how the temperature of the sediment recovers from the heat collection. The temperature variation of the liquid seems to correlate with the mean monthly air temperature. The selected methods clearly indicate that sediment energy seems to be yearly renewable because there is a clear correlation between air temperature and heat carrier liquid temperature.

Key words:

carbon-free, energy source, heat energy, renewable, sediment energy.