Conclusion

The information on site engineering processes (such as grading and fire prevention) combined with the results of the subsequent land and water use analyses, indicate that technology type and facility footprint have a number of implications for the effect of a project on the surrounding ecosystem. This analysis has yielded a variety of interesting results that help us to better understand how and to what degree these two variables act on the local environment. The analyses have demonstrated that certain technology types, such as dish/engine systems, show the promise of having both high land and water use efficiencies, which could make this technology type one of the most productive forms of solar development while also suggesting that it may incur a relatively lower amount of ecological impact. Likewise, these analyses demonstrated that one of the most effective design changes a facility can make to reduce its environmental impact is to utilize a dry-cooled system rather than a wet-cooled system.

However, it is important to note that the land use analysis also has some limitations. First, it constructs the disturbance ratio based on the amount of area that will be covered completely by various forms of infrastructure, such as roads, buildings, and the solar field. It does not include other types of disturbance or environmental disruption that may arise from other forms of infrastructure, which may still result in ecological impacts on the surrounding area and wildlife. Second, this form of analysis utilizes the area of disturbance as the key variable in assessing the relative land use efficiency of a project proposal. Caution should be applied with this approach as these project proposals are still in the permitting process and are therefore subject to design change. Should certain design changes occur, the relative land use efficiency ratio of a project might change as well. Third, although this tool primarily focuses on the relationship between the facility footprint and the amount of electricity generated by the facility, users should keep in mind that the size of the facility footprint also contains its own set of ecological and efficiency trade-offs. For example, solar energy facilities that utilize a dry-cooling system will inherently operate at a lower efficiency, and therefore developers will frequently expand the footprint accordingly to generate the same amount of energy as a smaller wet-cooled facility. For some users of this tool, the consideration of the amount of water use may be of greater concern than area of land use, in which case, they may weigh the results of the water use efficiency analysis more heavily. And finally, users of this tool should refrain from extrapolating the total environmental impact of a project from these ratios. Although land use efficiencies are undoubtedly helpful for comparisons among different projects and even various technologies, they remain a snapshot of the proposed development and are certainly not comprehensive in their scope of environmental assessment.

Regardless of a technology type’s relative land-use and water-use efficiency, the geographic location of facilities, as well as the biological resources associated with sites, will directly determine the type, intensity, and extent of landscape-level impacts from development.