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Energy Savings Calculators

Three quick, honest calculators — plain math on the numbers you enter, right in your browser (nothing is sent anywhere). They're estimates to guide a decision, not promises: your real results depend on your home, climate, usage, and utility rates.

1) Heat-Pump Payback

Roughly how long would a heat pump take to pay for itself from heating savings?

Your current heating cost per month, in winter ($) Months per year you actively heat Expected savings vs your current system: 30%
(typical real-world range is ~20–40% vs electric resistance or oil; less vs cheap gas) Installed cost after any incentives you already know you'll get ($)

Estimate only. Savings vary hugely with climate, insulation, electricity vs fuel prices, and the system you're replacing. Get real quotes and check your utility's rates before deciding.

2) Repair or Replace?

The classic 50% rule, honestly applied to an aging appliance.

Repair quote ($) Cost of a comparable new unit ($) Age of your appliance (years) Typical lifespan for this type (years)
(fridge ~12, washer ~11, dryer ~13, dishwasher ~10, water heater ~10–12)

Rule of thumb, not gospel: if a repair costs more than half a new unit AND the appliance is past half its typical life, replacement usually wins — especially if the new unit is meaningfully more efficient.

3) LED Swap Savings

What replacing old incandescent/halogen bulbs actually saves per year.

How many bulbs you'd swap Wattage of the old bulbs (W) Average hours on per day (per bulb) Your electricity rate ($/kWh — it's on your bill; U.S. average is ~$0.17)

Assumes an equivalent LED uses ~85% less energy (a 60W-equivalent LED draws ~9W). Bulb cost pays back fast, but exact savings depend on your usage and rate.

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