Analysis of financial and carbon savings of grid-tied home energy systems in conjunction with photo-voltaic solar generation and electric vehicle use

Abstract

The general downward trend of the costs of both battery and solar technologies has helped lead to their increased adoption on both utility and residential levels. These decreasing costs combined with the relative ubiquity of solar power presents a significant opportunity for homeowners to not only reduce their overall electric bill but their carbon footprint by pairing solar generation with home energy systems (HES). By incorporating HES, consumers are able “peak shave” to take advantage of favorable Time-of-Use electricity rates as well as capture excess power generated by solar panels that would otherwise be sent back to the grid as part of a net metering agreement or sold back at the “avoided cost” rate, which is often times unfavorable. Depending on the scale of said system, the consumer can significantly reduce their carbon footprint, or in some cases offset it entirely, even more so if they use an electric vehicle (EV). These carbon savings, in the presence of incentives, can also provide greater financial benefit in addition to the electricity cost savings. The overall cost and CO2 savings associated with installing such a system is a function of a variety of factors such as the solar availability, house load, incentives, rates, and the grid mix (coal, wind, nuclear, etc). All of these factors are regional; thus analyses of these systems must be done on a regional basis. In this paper, we model these systems using data from several regions across the United States and quantity the financial viability of these systems as well as their environmental benefit as measured by CO2 emissions reductions. As will be shown, the benefits differ depending on region as well as the time-of-use rate schemes deployed by different utility companies. It is hoped that yielding favorable results in both of these metrics will accelerate adoption of these systems and assist in the mitigation of climate change.