Horizontal ground heat exchangers modelling

•New model for horizontal ground heat exchanger.•Analytical model which is very fast and accurate with respect to numerical simulation.•A comparison with the classical trench model is performed.•Particularity of horizontal systems are discussed possible applications of the model are discussed. Geothermal heat exchangers applied to building air conditioning and heating systems are often categorized as vertical and horizontal configurations. In this article, an analytical model is presented to simulate on an hourly basis, ground heat exchangers having a horizontal configuration. The model is based on a new formalism of the finite line source approach that allows faster simulation. The model presents a novel approach to take into the effect of seasonal temperature variations especially when the inlet temperatures in the ground heat exchanger are imposed. It also takes into account the effect of the air-soil boundary condition and the thermal interference between the different portions of pipes in the buried field. The temperature as well as the heat flux distribution along the ground heat exchanger is part of the solution and not a priori assumed as in the case of previous models. The model does not consider the possible phase change due to ice formation or the moisture content variation associated with some horizontal configurations. It is based on recent studies related to vertical boreholes and adapted to horizontal systems. It is intended to be a valuable tool to simulate on an hourly basis, the time response of the ground heat exchanger coupled with a building equipped with heat pumps.