Spark Logo

Share in our latest insight and ideas in energy, from data visualization to best practices from the field.

in other words: Understanding How to Interpret Your Energy Use

Posted by Lester Shen  |  Date June 5, 2012  |  Comments 6

in other words is a regular feature of i.e. Every couple of weeks, we take a closer look at current events and trends in energy, ground them in relevant data and context, and offer our insight about their potential impacts and implications. We look forward to your input and feedback.

“Providing consumers with easy access to data on their energy consumption can help give them the tools they need to make informed decisions about their energy use. Developing applications and services to help consumers understand and control their energy use is a field ripe for American innovation.” -  US Secretary of Energy Steven Chu


Our residential energy efficiency program has provided Energy Snapshots to homeowners since 2008. Prior to each home visit, our program participants sign utility bill release forms, giving us access to the previous year’s natural gas and electric bills. Among other things, the Energy Snapshot shows the homeowner graphs of their monthly energy use compared to a calculated Minnesota average of like sized houses. To our “surprise”, not everyone intuitively understands these graphs nor do they delight in the insights so readily apparent on them. We have also learned that we need to train our home energy counselors on how to interpret the graphs and communicate them to the homeowner. With the increasing trend of customer feedback reports supplied by utilities as well as the greater accessibility to energy use data via smart thermostats, the smart grid and Green Button, now may be a good time to think about visual communication, visual literacy, and education.

Your average person may not have the graphical fluency to read a line chart. Expecting them to relate the chart to their actual energy use requires an additional leap of faith. Here are a few examples. What lessons can you draw from them? Leave your findings in the comments section below: (We’ll provide explanations in the comments section later in the week.)

Example 1:

Example 2:

Example 3:

Example 4:


Experience has taught us that homeowners need guidance to understand theses graphs, so our home energy counselors must be able to interpret the graphs and then explain their findings to the clients. We train our counselors with TWI techniques. Here’s the illustration we use to help our counselors understand the gas and electric energy use graphs:

Since electric and gas data are a direct manifestation of their energy use behaviors, these graphs’ content can provide a clarion call to energy saving actions. However, to make informed decisions, you need to know how to understand the information. According to a recent survey, only 24% of Americans consider themselves knowledgeable about energy. But four out of five are interested in learning how to use less energy, and 57% understand that energy savings will require behavior change and new technologies. How much do we need to educate our customers so that they can best interpret and use the information? More importantly, are we clear about our learning objectives for this? And then, what are the best ways to display this information to turn it into actionable knowledge? Lots of food for thought.

Contributing authors: Heather Hanson and Anna Jursik

Related CEE programs:

Community Energy Services

Related posts:

Look Before You Leap: Being a Desk Jockey Can Help You Do an Energy Audit

The Nest Thermostat: Saving Energy Can Be Fun

in other words: Green Button



Your key question is on target: what are the best ways to display this information (in an era of information-overload) to turn it into actionable knowledge? While there may be "surprise" that people don't intuitively understand graphs, let's connect with all sorts of energy users to find the answer to the question above.
Example 1 is a typical older Minneapolis home. The low base load use for both gas and electric show that this is not a high energy using family, while high usage of both gas and electric in the winter months are indicative of heat loss and/or inefficient heating equipment. Though increases in electric use are also often seen in the winter months as a result of longer lighting hours and holiday lights, assuming the homeowner keeps the thermostat set in the normal range, a home exhibiting these graphs would most likely benefit from attic air sealing and attic and/or wall insulation, along with an upgrade to a high efficiency heating system.
Example 2 is a high base load user (nearly twice the base load use of the MN average) as a result of domestic hot water use, cooking, and possibly clothes drying. This could be a result of a very high hot water temperature, high occupancy in the house and/or a number of young children in the house. On first glance the user looks like an average user for space heating but taking into account the high base load use, the space heating use is actually quite good.
As can be seen by the graphs, Example 3 is a high energy using home. There are many factors that contribute to these types of graphs, but most significant is the high summer use which can be attributed to the presence of a heated outdoor swimming pool. The consistently high usage found throughout the year also suggests that this home could benefit from some energy upgrades such as air sealing, insulation, and/or high efficiency heating equipment, as well as discussions about behavioral change with its occupants, such as on electric use or thermostat settings.
Lower than average year round gas use coupled with higher than average year round electric use is often seen in homes that utilize air source heat pumps as their primary heating source, as is the case with Example 4. For this home, the higher gas usage in the winter is likely due to standard furnace use when the temperatures are too cold for the heat pump to adequately heat the home, and the increase in electric use in the summer is likely due to the use of air conditioning.
The Green Button technology should be a great addition to getting people easy access to their utility bills and based on the surveys it seems as though they want to learn more. A challenge to worrying about energy costs has been the mild past winter coupled with very low natural gas cost. However, many more citizens are becoming aware of the environmental impact of their energy use, especially electricity and carbon dioxide emissions. This can be a method for more scrutiny of the energy use. While it is very helpful to have utility billing information to determine energy efficiency opportunities, we often find that the automatic billing process takes any human evaluation out of the equation, even on a monthly basis. It gets paid with a direct deposit, then out of mind. Lastly, we get a lot of feedback from customers who receive a summary of their energy use compared to the neighbors. Although this does not necessarily give them any specific information about their utility costs, it compares them to others in the neighborhood. When they are using more it definitely gets their attention. When they are using less it has been my experience that they do not care as much about their energy bills.

Leave Your Comment