Solar Water Heating Calculator

This calculator provides consumer information on the energy, cost and environmental savings potential of residential solar hot water systems in Florida. The calculations and assumptions were modeled on the solar system calculator tool (SHW-calculator_simple.xls) available for Microsoft Excel and developed by FSEC’s Deputy Director, Philip Fairey. To use this calculator, answer the two questions under the heading "Basics Solar System Information" using the pull-down menus provided. For the input "Florida Climate Zone," if your home is north of Volusia County, select "North" and if your home is south of St. Lucie County, select "South." Otherwise, select "Central." The calculator depends on a number of pre-selected assumptions. To view and change these assumptions, select the checkbox below and the additional input fields will appear. If you choose to not change these assumptions, simple uncheck the box below anytime.

Basic Solar System Information

# Of People Living In Home: Florida Climate Zone:

Assumptions Used By This Calculator

Solar System Energy Factor: Standard System Type:
Hot Water Use Intensity: Discount Rate: % per annum
Solar System Cost: General Inflation Rate: % per annum
IRS Credit (30% of Cost): Retail Electricity Price: $/kWh
FL State Rebate: Retail Natural Gas Price: $/therm
FL Utility Rebate Amount: Fuel Escalation Rate: % per annum

Solar Savings Results

Annual Energy Cost Savings: $/year Annual CO2 Savings: lb/year
Annual Solar Energy Savings: kWh/year Annual Solar Fraction: %

Economic Results

Internal Rate of Return: per annum Simple Payback Period: years
Cost of Solar Energy: cents/kWh Net Present Value: present $’s