An Experimental and Numerical Case Study of Passive Building Cooling with Foundation Pile Heat Exchangers in Denmark

Abstract

Technologies for energy-efficient cooling of buildings are in high demand due to the heavy CO2 footprint of traditional air conditioning methods. The ground source heat pump system (GSHP) installed at the Rosborg Gymnasium in Vejle (Denmark) uses foundation pile heat exchangers (energy piles). Although designed for passive cooling, the GSHP is used exclusively for heating. In a five-week test during the summer of 2018, excess building heat was rejected passively to the energy piles and the ground. Measured energy efficiency ratios are 24–36 and the thermal comfort in conditioned rooms is improved significantly relative to unconditioned reference rooms. A simple model relating the available cooling power to conditioned room and ground temperatures is developed and calibrated to measured test data. Building energy simulation based estimates of the total cooling demand of the building are then compared to corresponding model calculations of the available cooling capacity. The comparison shows that passive cooling is able to meet the cooling demand of Rosborg Gymnasium except for 7–17 h per year, given that room temperatures are constrained to < 26 °C. The case study clearly demonstrates the potential for increasing thermal comfort during summer with highly efficient passive cooling by rejecting excess building heat to the ground.

Application and Validation of a Dynamic Energy Simulation Tool: A Case Study with Water Flow Glazing Envelope

“…Ground Source Heat Pumps (GSHP) exploit the nearly constant ground temperature over the year to increase their performance coefficients. GSHP fit well in the low-CO2 energy supply system [13]. The soil mass is considered a great means of thermal energy storage, and the temperature oscillations are reduced at 10-20 m depth over the seasons.…”

“…(A v i 0 ) is the sum of the energy absorbed by the water chamber and the energy transferred by convection because of the glass panes absorption. A v comes from Equation (13).…”

Study on the operation strategies and carbon emission of heating systems in the context of building energy conservation

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Full-Scale Demonstration of Combined Ground Source Heating and Sustainable Urban Drainage in Roadbeds

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