ENERGY USE OF NON-RESIDENTIAL EARTH-SHELTERED BUILDINGS IN FIVE DIFFERENT CLIMATES*

ABSTRACT Computer predicted HVAC energy consumption of earth-sheltered single story office buildings and dry-storage warehouses indicate that increased earth-sheltering may significantly reduce energy requirements and peak demand. Buildings in Boston, Massachusets; Washington, D.C.; Jacksonville, Florida, and San Diego, California in the United States and Manila in the Philippines were modeled. For the office building in Boston where the largest heating energy reductions were calculated, the heating energy for the bermed and covered building was reduced to 45% of that calculated for the slab-on-grade configuration. The corresponding peak load was reduced to 35% of the slab-on-grade value. Cooling energy reductions were also predicted for the office buildings. The Washington, D.C. bermed and covered office building had predicted cooling energy requirements that were 61% of those for the slab-on-grade building. Warehouse results are dominated by uncontrolled infiltration at the loading dock doors. Consequently, the impact of earth-sheltering is less on a percentage basis than for the office building. For Boston weather conditions, the bermed and covered warehouse has a heating energy requirement that is 70% of that for the slab-on-grade building. However, wall, roof and floor thermal performance improved dramatically with increased earth-sheltering because the low 55°F heating thermostat setting, which is suitable for the dry-storage warehouse, is close to the annual mean ground temperature. Computer analysis is used to associate energy loads with the wall, floor, roof and windows, to determine the energy load due to infiltration and ventillation, and to estimate the internal load. Systematic changes in the energy requirements associated with these components of the HVAC load that correspond to changes in the degree of earth-sheltering are analyzed to quantify the improvements in thermal performance due to the major features of earth-sheltering.