Below is a post I published on calculating a home energy use by region using a tool my utility (Georgia Power) provided (made by Apogee). It's a nice tool to show homeowners if their utility provides something similar. It could help you validate how improvements to the home can help save energy.
Usually when I receive emails from my electric utility, Georgia Power, promising to offer energy saving tips I ignore them because they are just too basic. The other day I got an email that said the following:
High temperatures can impact your monthly electric bill because your air conditioning system must work harder to keep your home comfortable. To help manage this potential impact, I invite you to use our free online tool to find personalized ways to save. You’ll also find out where you use the most electricity in your home and why your bill changes from month to month.
So I decided to play along.
The problem I've had with most energy tip websites that show breakdowns of how homes use energy is that they aren't specific to each region and climate zones. When we covered Household Energy Usewe showed a breakdown of how a typical single family home uses energy, but not every home is going to be typical. You can see that breakdown below:
My concern with the above chart is that I was convinced I spent more money cooling my home in the summer than I did heating it in the winter.
Which is where the energy checkup tool provided by Georgia Power comes in. The tool is a home energy calculator produced by Apogee, who provides software solutions to utilities. I started by telling the tool which region in Georgia I lived in, and then spent about 5 minutes filling out questionnaire which asked things like the the type of home I lived in (middle town-home), how many square feet, how many people were there and away during the day, what my thermostat is set to during the summer and winter (more on this below), what type of windows, how many lights have I changed to fluorescent (percentage based), how I cool (electric air conditioner) and heat (natural gas furnace), etc. I've filled out many of these questionnaires and this one was relatively painless. It was much easier than the original questionnaire that the now defunct Microsoft Hohmtried to get me to fill out but I gave up after 20 minutes.
The summary of the information I entered can be seen below (it's not 100% accurate, but very close)
You can see that cooling definitely makes up the most of my energy spend. What I like most about the report that was generated is that it relies heavily on charts and graphs, which really help users visualize where their money is going.
My biggest complaint with the questionnaire is that it doesn't spend enough time on thermostat setting. It asks you to pick one temperature for the heating setting and one for the cooling setting, and at the bottom of the page explains :
Please select a temperature that is the effective average temperature in your home during a 24-hour period. For example, if you keep your thermostat at 70 degrees during the day and at 64 degrees for 8 hours each night, your effective average temperature would be 68 degrees. (Note: Programmable thermostats create an effective average temperature by making temperature setting changes automatically at the times that you designate.)
But for people with programmable thermostats, most know what they set the thermostat at for different times during the day (home, away, sleep) so why not allow users to fill in the times and settings if they know them? I think that would provide a more accurate approach to understanding the largest energy consumer in the home. Then the suggestions the tool produces could be more precise (i.e. "try turning up the temperature of your downstairs in sleep mode in the summer to 80º instead of 78º").
At this point you're probably wondering, "So how does this tool compare to reality?". Well, let's look at my actual bill amounts for electricity and natural gas below:
While I'm missing August in the real world comparison, if you compare the image above to the one at the top of the post (which was taken from the report), you can see that they are very close to each other! Once I update the graph with the August bills, I expect them to be much lower than July because August was not nearly as hot.
If you live in a hot climate where your air conditioning system makes up the bulk of your home's energy load, you may want to dig a little deeper and check out our post on Air Conditioner Power Consumption.
What other tools have you found that help you calculate where and how you use energy?