IMPACT OF SHADE ON HVAC ENERGY CONSUMPTION IN BUILDINGS: A RESIDENTIAL CASE STUDY

摘要

The impact of shade on the heating, ventilation, and air conditioning (HVAC) energy consumption in buildings is not automatically included in whole building energy simulations. Using transient system simulation (TRNSYS) software, models of the Union County Housing Authority's energy efficient duplex enable the calculation of a monetary value for shading from trees, adjacent buildings, or shade structures such as solar panels. The value for shade was determined by calculating the difference in shaded versus unshaded energy consumption of the building for the month of July in central Pennsylvania. During the month of July, it was found that a large tree located to the south of the building could save approximately 4.7% in cooling demand and 3.3% on the electricity bill for the duplex. This value for tree shade is conservative because the detailed radiation mode in TRNSYS does not discount irradiation from shade projected on exterior surfaces other than windows. Solar panels shade the building's roof, reducing the cooling demand by 0.57% and the electricity bill by 0.4% from the shade alone.consumption in small buildings has not been quantified. Shading during the summer months is beneficial because blocking the sun's radiation can reduce the cooling needs of the home. Low carbon footprint electricity generation from photovoltaic panels is a known benefit but the value of the shade the array projects on the roof and house are uncertain. Values for shade from a tree or solar panels can be calculated by simulating the reduction in energy consumption produced from shade. The specifications and data of the Union County Housing Authority's (UCHA) low-income energy efficient condominium (duplex) will provide a case study for researching the value of shade by creating whole building simulations in TRNSYS 17. Results provide insight into the under-explored and overlooked benefits of solar panels and passive solar design. The UCHA has partnered with The Pennsylvania State University to receive recommendations for future investments in their new building construction and retrofits.