Enhancing the energy conservation benefits of shade trees in dense residential developments using an alternative tree placement strategy

Abstract

Modern residential land development has trended toward densification, resulting in limited greenspace on individual parcels. As a result, land developers and homeowners are often constrained for space to plant shade trees. This can result in suboptimal placement of shade trees for the provision of energy conservation benefits. Using a simulation program called EnergyPlus, we examined the effects of existing trees on the energy consumption of recently constructed homes in three U.S. cities with distinctly different climates: Metro Minneapolis, MN, Charlotte, NC, and Metro Orlando, FL. Remote sensing was used to identify placement of existing trees around the homes, revealing that there were 1.5 to 2.9 trees within 15 m of the homes on average. These existing trees, when modeled as large-stature deciduous trees in the simulator, provided average annual energy conservation benefits per parcel of 14 kWh (MN), 25 kWh (NC), and 44 kWh (FL). We then developed an alternative tree placement strategy that spatially reconfigured the existing trees to both minimize space conflicts and maximize energy savings. This alternative strategy significantly improved annual energy savings per parcel to 57 kWh (MN), 47 kWh (NC), and 103 kWh (FL). Our alternative tree placement strategy was equally effective as the conventional strategy (always plant a shade tree on the west aspect) in MN and NC, but not in FL. However, the alternative strategy was more responsive to space constraints and therefore could be used to maximize energy savings while concurrently minimizing space conflicts between trees and site uses.

Virtual Geographic Simulation of Light Distribution within Three-Dimensional Plant Canopy Models

“…Light is a major ecological factor that influences plant growth and development [7]. The distribution of light within a plant canopy is a valuable research issue that is beneficial to our understanding of light propagation, light distribution, and even for urban green land micro-climates [8,9]. The light distribution within a canopy determines the energy availability for a large number of physiological processes (e.g., photosynthesis and transpiration).…”

Cooling Benefits of Urban Tree Canopy: A Systematic Review

“…Urban high temperatures caused by the UHI effect affect the thermal comfort of the human body and even cause a series of health problems, such as heat stroke, breathing difficulties, heat cramps, dehydration, and so on [4]. The UHI effect also raises night temperatures, increasing electricity demand and building energy consumption for cooling [5][6][7]. These problems have seriously affected human health and limited the sustainable future development of cities.…”

Assessing the Likelihood of Failure Due to Stem Decay Using Different Assessment Techniques

“…Urban forests and greenspaces are increasingly considered an important priority for improving the sustainability, resilience, and livability of the urban landscape [1]. Trees in the urban forest provide many benefits such as air pollution reduction [2], storm water runoff attenuation [3], carbon sequestration [4], and building energy conservation [5]. Benefits generally increase as the size of trees increase [6], but as trees mature they are more likely to develop decay that increases their likelihood of failure [7].…”