About These Calculators
Tools for homeowners planning to reduce or eliminate their dependence on the grid. Size generators, calculate solar ROI, optimize time-of-use rates, and plan battery storage.
Energy Independence Calculators
14 toolsHome Battery Backup Sizing Calculator
Find out how many batteries you need for backup power and how much it costs after tax credits
EV Charging Cost vs Gas Savings Calculator
Compare the true cost of driving electric versus gas over 5+ years
Solar Payback Period Calculator
Calculate how long solar panels take to pay for themselves and your 25-year return on investment
Time of Use Electricity Rate Optimizer
Optimize your electricity usage to save money on time-of-use rate plans
Whole Home Generator Sizing Calculator
Size and cost a whole home backup generator based on your appliances and electrical needs
Net Metering Savings Calculator
Calculate solar net metering savings based on your production, usage, and utility rates
Energy Audit Savings Estimator
Estimate home energy savings from common efficiency upgrades identified in an energy audit
Wind Turbine Calculator
Calculate wind turbine energy output and payback period based on wind speed and turbine size
Geothermal Savings Calculator
Calculate savings from installing a geothermal heat pump vs traditional HVAC
Off-Grid Battery Calculator
Size your off-grid battery bank for reliable energy storage and backup power
Wind Turbine Output Calculator
Estimate annual energy output and savings from a small residential wind turbine
Battery Backup Duration Calculator
Calculate how long a battery backup system will power your essential loads
Solar Battery Sizing Calculator
Size your solar battery bank for off-grid or backup power
EV Charging Station ROI Calculator
Calculate return on investment for installing EV chargers
Frequently Asked Questions
Are these energy independence calculators free?
Yes, all 14 calculators are completely free with no signup required. They run entirely in your browser — no data is sent to any server.
How accurate are these calculators?
Our calculators use industry-standard formulas and are regularly updated. However, they provide estimates — always verify critical calculations with a professional in the relevant field.
Can I use these calculators on my phone?
Yes, all calculators are mobile-responsive and work on any device with a web browser. No app download needed.
Do you save my calculations?
No. All calculations happen in your browser. We don't store any of your inputs or results. Your data stays on your device.
Can I embed these calculators on my website?
Select calculators offer embed codes that you can copy and paste into your website or blog. Look for the "Embed This Calculator" section on individual tool pages.