As interest in distributed renewable generation and home energy system intensifies, it is useful to understand the underlying economics of such systems. Although there are many configurations for home energy systems, we have looked at a system including photovoltaic power generation, battery energy storage, electric vehicles and a control system with moderate load control. We are not including energy efficiency in the system evaluation, as many core energy efficiency measures are economically positive and should be implemented before installing home generation and power storage. This provides a better underlying demand that avoids installing excess generation and storage than if energy saving measures are implemented later. However, some load control and demand response is included that allows improved matching of the home power demand and supply.
The return on home energy systems varies significantly based on location, as local consumption patterns, driving culture and renewable resource have large impacts on the economics of the system. In this analysis, public incentives (including subsidies, rebates or tax benefits) are explicitly excluded to allow evaluation of the underlying economics and comparison across markets.