The Solar Calculator is a beginner-friendly Excel tool developed by the University of Maryland Environmental Finance Center to help drinking water and wastewater utilities explore the feasibility of on-site solar energy. Using facility location, available space, electricity rates, and monthly energy use, the tool provides early estimates of solar system size, solar energy production, and cost savings that can support planning, decision-making, and grant applications.
Built on the NREL’s PVWatts model, the calculator generates easy-to-understand results and charts. This tool is intended for early scoping only. Final system design should be completed with a qualified solar developer.
*This tool requires excel-macros, which is embedded code to enhance the functionality of the tool. Please refer to the educational video for how to enable macros.
**Additionally, the individual document can be unblocked manually by right-clicking and selecting properties on the Solar Savings Calculator document in the file folder. Refer to the Microsoft support page for micros for further details.