Simplified method for underground heat transfer calculation

A simplified heat transfer calculation method for underground buildings is developed. The method is based on the results from the ITPE method and is suitable for seasonal heat loss calculation. The simplified method consists of a set of equations for estimating the monthly total heat flow between an underground building and ground as a function of a wide range of variables such as building dimensions, insulation configurations, and soil thermal properties. The equations are designed to accept continuously variable input values. The simplified method predictions are tested against the ITPE results. The agreement between the correlations and the ITPE method is found to be within 10 percent for annual means, amplitude, and phase angle of total building heat loss.