Effect of Different Landscapes on Heat Load to Buildings

Abstract

Strategies to conserve water have been implemented by many municipalities in the US Southwest to minimize quantities of water used for irrigating urban landscapes. Some of them encourage and even enforce homeowners to remove the turfgrass to reduce the irrigation water demands. This strategy not only ignores the numerous benefits derived from the turfgrasses but also fails to recognize the energy savings for the buildings surrounded by green landscapes. Quantitative analysis of the effect and importance of different types of landscapes on urban heat load and the subsequent energy consumption inside those buildings is of great practical need. Field experiments were conducted at New Mexico State University to assess the effect of different landscapes on heat transfer and ambient air and surface temperatures from June 2017 to October 2018. Two standard wood frame walls covered with stucco and surrounded by either Kentucky bluegrass or by hardscape were set up and equipped with sensors, measuring wall and air temperature, relative humidity, wind speed and the solar and far infrared radiation balance. Our results show that overall heat load from the xeric landscape is noticeably higher than the one from the grass landscape. Based on these data, we assessed the potential for energy savings by utilizing turfgrass landscaping.