Compare Electricity Bills

It's difficult to compare your electric bill to someone else's bill. So many things could be different - the hours you're home, your appliances, your air conditioning preferences, the size of your home, how many people are in your home, and whether or not you have a pool or hot tub.

Instead, compare your own electricity bills one month to the next or one month to the same month the previous year. This will give you some baseline information about your current expenses and provide you information on the results you might be seeing from your own efforts to reduce electricity usage.

Above is a snapshot of my own electric bill. I did edit the invoice to show the same information from July 2008 below the information for July 2009 and to block my personal information, but other than that it is untouched. The point is not for you to compare your bill to mine, but to show you how I walk through comparing my own activity from one month to another.

On-Peak Usage - On-Peak Kilowatt Hours divided by Total Kilowatt Hours
Determines how well you did at minimizing on-peak usage. I try to keep this less than 10%.

Total Kilowatt Hours Used - No calculation for now but note whether or not your total usage has gone up or down.

Average Kilowatt Hours Per Day - Total Kilowatt Hours divided by Number of Days in Billing Period. You really want to know your daily usage in order to make accurate comparisons of bills that had different days. Otherwise, you could be misled into thinking you were doing well at lowering your bill when, in fact, there were just fewer days in the month.

Cost Per Kilowatt Hour - Divide Total Charges by Total Kilowatt Hours. This will give you the cost per kilowatt hour in order to understand the impact of any changes you've made. Maybe you used fewer kilowatts but had too great a share in the peak times. This calculation will tell you how well you did at reducing the actual cost of each kilowatt.

Calculation

On-Peak Usage

Total Kilowatt Hours Used

Average Kilowatt Hours Per Day

Cost Per Kilowatt Hour

July 2009

8.9%

4618

149

$0.085July 2008

9.8%

5702

197

$0.081

Notes:

Yay! We used less peak time energy and we used fewer kilowatt hours in total and on a per day basis. Good!

WHAT??July '09 was $0.085 per kwh vs. July '08 of $0.081. Now, isn't this interesting? I used less electricity this year than last and had more of it on the cheaper off-peak hours, but I paid more per kilowatt hour this year than last. Why would that be? Because the electric company raised rates between July '08 and July '09. Good thing I reduced my usage. At last year's total usage of 5702 and this year's more expensive rate, my bill this July would have been about $484 instead of the $392.89 I was charged!

Note: The cost per kwh is not an exact calculation using the method above because my total charges include things like taxes and fees that have nothing to do with the kilowatt hours used. For a more exact comparison, remove those charges from the Total Charges before completing that calculation.