SCARY MATH for FRUGAL PEOPLE: PRICING YOUR POWER
How Much Do You Pay Per kWh?
For example, our bill was $223.
Our total amount of kWh consumed was 2,854.
$223 divided by 2,854 = 0.0781, or 7.8 cents per kWh
Now for the fun stuff...
Most of our light bulbs are 60 watt. To find out how much each light bulb costs per hour, let's do the very scary math:
Instead of running my numbers per hour, I'm going to go by 24 hours - otherwise, these numbers would just be tiny and annoying :)
First, we'll multiply 60 watts by 24 hours to get the total amount of watts used.
60 watts x 24 hours = 1440 watts
Then, let's turn this into kilowatts by dividing by 1000.
1440 divided by 1000 = 1.44 kilowatts
Last, we can multiply our kilowatts by our cost per kWh.
1.44 x 7.82 = 11.26 cents per 24 hours
Each 60 watt light bulb we have costs 11.26 cents per 24 hours to operate. That means the cost per hour is less than half a cent. Hmm...that really doesn't sound so bad, does it?
Here's how the numbers break down for us:
- IF we leave our 3 outside lights on 24 hours per day (which happens frequently), that's 34 cents per day or $10.20 per month.
- IF we leave 4 light bulbs burning in our kitchen (the equivalent of one ceiling fan and the light above our sink) for 12 hours per day, that's 22.52 cents per day or $6.76 per month.
- IF we leave both our ceiling fans on in the living room (just the lights) for 8 hours, that 30.02 cents per day or $9.01 per month.
- IF we leave the master bath lights on for 4 hours, we're spending 15.01 cents per day or $4.50 per month.
- Plus, if we leave our guest bathroom lights on for 6 hours, that's 11.26 cents per day and $3.38 per month.
- If we leave our bedroom lights on and Emma's bedroom light on for 6 hours per day, that adds up to $4.21 per month.
The final number...
While the numbers above might not seem like much, that adds up to $38 per month JUST FOR LIGHT BULBS!
That seems a bit excessive. What do you think? If you've done the math, how do your numbers add up?