- DALC Staff

# How CLEA-N Calculated Energy Savings for the LED Exchange

Here is the EPA link and the formula used to calculate the annual reduction in carbon emissions:

https://www.epa.gov/energy/greenhouse-gases-equivalencies-calculator-calculations-and-references

37.2 kWh/bulb/year x 1,558.8 pounds CO2/MWh delivered electricity x 1 MWh/1,000 kWh x 1 metric ton/2,204.6 lbs = **2.63 x 10-2 metric tons CO2/bulb replaced**

With the new updated numbers, the calculation is as follows: .0263 x 7500=** 197.25 metric tons**.

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*Bottom Line...Since November, CLEA-N has delivered 7,500 LED bulbs to 1,100 households, which over the life of the bulbs, will reduce utility costs by over $550,000. *

Here's how we calculate the cost savings on utility bills.

- Each LED bulb uses just 11 watts of energy but is 75 watt equivalent.

- Each LED bulb is expected to last 15,000 hours, or 13.6 years at 3 hours per day.

- Our Alliant Energy bill shows our local rate is $.1166/kWh.

- We used an online energy cost calculator, with 3 hours per day per bulb.

- 75 watts of energy (with incandescent) would cost $9.58 to operate a bulb for a year.

- 18 watts (75 watt equivalent CFL) would cost $2.30 to operate a bulb for a year.

- 11 watts (75 watt equivalent LED) would cost $1.41 to operate a bulb for a year.

- Since CLEA-N launched, we have impacted just over 1,100 households, with just over 7,500 bulbs given out.

When we did the swap/exchange portion of the project, we saw 64% incandescent and 36% CFL exchanged. Assuming that ratio holds true across all the households...

- 64 Watts (reduction/savings on incandescent to LED) is saving $8.18 per year.

- 7 Watts (reduction/savings on CFL to LED) is saving $0.89 per year.

- Energy cost savings for incandescent replacements is calculated at $534,000.

- Energy cost savings for CFL replacements is calculated at $32,000.

**Therefore, we estimate the total cost savings, over the life of the LED bulbs, for the folks who received LED bulbs from CLEA-N, is over $550,000!! **