Savings calculator
Your bulbs, your hours, your tariff. The same arithmetic our energy auditors use, running live in the page — nothing is sent anywhere.
Savings calculator
Your lighting
How many bulbs?
Hours on per day
Your rate, cents per kWh
Take the rate from your bill rather than guessing. It is the input that changes the answer most, and it varies by a factor of three across the country.
What it works out at
$0Saved per year
$0Over ten years
0kWh saved a year
0kg CO₂e avoided
Carbon figure uses 0.386 kg CO₂e per kWh, the current US average grid intensity. Your local grid may be cleaner or dirtier.
What this does and does not include
Read this before you quote the number
Included
- Direct electricity for the lamps, at your rate
- The wattage difference for a like-for-like lumen replacement
- Ten-year projection at today’s rate
- Carbon avoided at US average grid intensity
Not included
- Lamp purchase cost, which is typically recovered in under a year
- Avoided replacement lamps and the labour to fit them
- Reduced air-conditioning load, worth roughly another 30% in cooled buildings
- Demand charges, which can be a quarter of a commercial saving
- Utility rebates
Want the measured version?
Our energy audit service logs your circuits for a fortnight and models the saving against your actual tariff, demand charges included.