Hi, I'm simulating a ground source heat pump coupled with vertical borehole heat exchangers, for heating and cooling an office building. During cooling season it rejects to the ground more heat than what it absorbs during heating season, so I'd need to analyse the increase of ground temperature. Is there a way to simulate the effect of thermal imbalance of the ground with OpenStudio, EnergyPlus or other software? Thanks.
EnergyPlus can simulate the vertical borehole heat exchangers with the GroundHeatExchanger:Vertical object which it documented here.
One of the outputs is the Ground Heat Exchanger Average Borehole Temperature so you should be able to see the temperature of the ground. There are many example files that use that object but you might want to start with looking at the GSHP-GLHE.idf file as a starting point.
Average borehole temperature is not a good indication of long-term increase of ground temperature. The undisturbed ground temperature is an input in E+, but E+ does not give ground temperature as an output. The model assumes that the undisturbed ground temperature stays constant, which makes its capabilities of simulating GSHPs over a long time period somewhat limited.
Comments
You may want to look at Kiva if you are getting unexpected results from EnergyPlus.