Tracing down your Energy Woes with Energy FootPrint (Project 1: Rapid Prototyping)

If you ever wondered exactly why on earth your utility bills are so high, and where to even start saving electricity from, Energy FootPrint is just the right app for you.

Energy FootPrint is an affordable alternative solution to the energy monitor that requires physical installations in the home. It tracks the energy usage of individual home appliances to educate the user on how they are utilising electricity in the home, and start reducing electricity usage by being reminded of their energy saving goals input into the app.

User Research

This project started off with a topic being assigned to us by our partners. My topic was ‘Smart Homes’ which was a rather broad topic. We had to interview our partner and other people in order to identify a problem that needs solving.

Topic Map to narrow down the scope

As the topic of smart homes could be very broad, I decided to approach the subject by starting with a topic map, narrowing it down to a few broad categories, namely home organisation, security, saving energy and time management. I formulated my initial interview questions using these topics as a guide, but tried to leave them vague enough in case any of the interviewees have interesting feedback.

I interviewed a total of 5 people, to find out what they knew about smart homes and what kind of problems they faced with maintaining their home. In my first round of interviews, I found myself reaching a few dead-ends and found out that this was because I was steering my questions in a certain direction. With this in mind, I revised my questions a few times to make sure they were fairly open-ended and not skewed to a bias.

Interviewing in progress

My final main questions are as follows:
1. What are some of the household appliances you use often?
2. Describe what you like or dislike about these household appliances.
3. If it was possible, what kind of improvement would you like to see in your home?
4. Describe a typical day at home for you.
5. What do you think of monthly utility bills?
6. Would being able to keep track of your energy usage be useful?
7. Do you have a problem with cleaning and organising in your home?

Based on how they answered the above questions, I tried probing further to get more input about their feelings and experience regarding certain topics that they were feeling stronger about.

Grouped by User
Grouped by Key Statements


There was a variety of household concerns that people thought could be addressed, such as cleaning, organisation, having their household appliances more time-sensitive/effective. Because all interviewees had slightly different needs, it took me quite a while to find a common thread. I wrote out all the key points of each interview on post-its, using a different colour for each user and did affinity mapping. Eventually, I was able to group them by different key statements, each one saying something about a certain lifestyle trait.

There were 5 key statements that I had narrowed down my observations into:

  • Users wanted to know how much energy their electrical appliances were costing them
  • Users had certain frequently used appliances that they thought were responsible for their high utility bill
  • Users found the cost of their utility bills too high
  • Users can sometimes be forgetful about wasting electricity, even though they make an effort to reduce wastage
  • 4 out of 5 users lived within a family unit

I noticed that a few of the key statements were pointing towards a similar problem: That all the interviewees had concerns over energy usage, and these were mostly stemmed from worrying over the cost of utility bills, especially in regards to electricity. 3 out of 5 users found that their bills were too high, while 1 user wanted to be aware of why her utility bills would surge or dip comparing to the previous month’s.

Using these findings, I narrowed down to a single problem statement
“I would like to be more aware of how I am using my electric appliances, because I want to reduce my utility bills”

The Solution

With the problem statement in mind, I understood that there were a few things my app needed to solve:

  1. It needed to track individual home appliance’s usage of energy
  2. It needed to let the user know how much their energy usage was costing them in terms of cash value
  3. It should encourage the user to actively reduce energy usage aka reduce their monthly utility bill

I felt that I needed a tangible user to cater the app for, so I put together the key statements in my affinity mapping to come up with a user persona:

“Esther, a 30-year old working mother, who is making efforts to reduce her electricity bill, but has no idea what is causing the jumps in her utility bills from month to month.”

As the topic of smart homes is something bordering on technology that exists and technology that hasn’t become reality yet, I did some research on existing smart home technology that monitors energy usage. I also found out that Singapore Power has an energy audit calculator on their website. I based my solution on this and the research on smart electric meters in the UK. This solution is based on the assumption that Singapore Power is able to make estimations of what the average consumption of several household appliances are.

User Flow

I came up with a user flow based on my user persona and the key needs of the user. With the assumption that it is very possible for Singapore Power to track down energy usage of individual appliances, I figured that an affordable way to keep track of a household’s energy consumption would be to link the respective electric meter to the user and tap into Singapore Power’s database on energy consumption.

First, I broke down the steps of what the user needed to do, by making a list of steps. When I was satisfied that all the steps were accounted for, I arranged them into a user flow diagram.

Final User-flow


System flow sketches

Now that I had my user flow, I made a quick wireframe to give an estimation about how many screens the app needed. I then worked on the actual screens. Between the user flow, wireframe and actual screens, I went back and forth with a few iterations, namely with the sign-up process.

A key feature of the app was associating the user with the registered electric meter no. I had to take into consideration that not everyone knew what that number was or how to find their electric meter, so I came up with a feature that would allow the user to enter their home address, and the respective electric meter would be found.

Prototype and User testing

As this was a rapid prototyping class, I decided to take the challenge of sketching my screens. I went through 3 iterations: First with a paper prototype, then another time after I compiled my screens with Marvel on mobile, before I made the final prototype in Invision. I decided to go with making a quick mobile prototype with Marvel after the first iteration in order to see the reaction towards some of the lengthier processes. I felt like there was more patience allowed when I was doing the testing with paper prototypes.

The feedback I got from the first paper prototype testing was that it was unrealistic that the app could detect what sort of heavy-usage appliances were in the house. It was more realistic if the user had to choose what appliances they wanted the app to track, and based on the wattage of the appliance, the app would be able to detect the appliance used based on the charge going through the electric meter. With that, I changed the user flow by adding that the user had to manually pick out the brand and model no, thus coming up with the wattage of the appliance based from the database. I also got feedback on the aesthetic of the screens, that the buttons on the home screen were not obvious enough, and the fact that if an appliance had gone over the target limit, that it should be ‘screaming out more’. I fixed this by adding a red colour to the exceeded statistics on the home screen, as well as red indicators in the individual appliance stats screen.

It was further brought up to me that it was impossible for Singapore Power to have access to wattage of every appliance out there in the world. So it would be better if instead of a dropdown menu, that the “Add Appliance” feature would consist of a search bar, and an option to add wattage manually. This is one of the things I’d improve and add for future developments.

On the second iteration, I tested the app on Marvel with 3 people. This time there were more minor changes, such as the “Add Target” screen not being clear as to how users would be notified if they were to get close or exceed their limit. I wrote a clearer message about the user being notified via push notifications to fix this. 2 more major issues were brought up:

That a “Profile” section seemed unnecessary, as this was an app for personal use and not social. I agreed with this, as I had no intention of implementing sharing features. I fixed this by changing “Profile” into “Settings” where the user could update the necessary information such as their address, electric meter no, and push notifications.

Sign-up iteration

Lastly, I got feedback that the sign-up process seemed tedious. It was brought up that it wasn’t pleasant to have the first screen being a long list of sign-up/ login options. I mulled over this for a while, as it was an important step that the user signs up for an account and provide their electric meter no, which to me, felt like something that should be kept secure. Because I couldn’t compromise on security, I decided to improve the sign-up process by breaking it down and making it shorter. On the first sign-up/log-in screen, I cut down the options to simply “New User” and “Login”, whereby a user who has already logged in wouldn’t see the first screen anyway unless they logged out deliberately. On the sign-up process, I consolidated 2 screens together by putting the electric meter no. as the first action, so that the new user would understand why they had to create an account.

The App

After making the iterations and improvement, I tested the mobile prototype with 2 more people to make sure that I had most of the major issues covered. I created a final prototype in Invision, as the Marvel mobile app has some restrictions when it came to linking.

You can check out the app on InVision and my presentation.

Future Developments

As this was just a 3-day rapid prototyping exercise, there are still areas that I have yet to explore for this app. For future developments, I’d like to explore on implementing the following:

  • Manual options and search bar for the “Add Appliance” feature
  • Being able to show the average usage of the appliances to give the user a better frame of mind on how much energy consumption is “normal” for a particular appliance
  • A smart “budget” feature to suggest to the user on how they can allocate their energy usage per month

Lessons Learnt

From this short 3 day exercise, I have learnt quite a lot, especially on the art of conducting interviews.

  • Never ask leading questions, or ask for opinions. Always ask questions to look for past experience and behaviour
  • Try to keep an open mind during interviews because you never know where that might take you
  • When doing affinity mapping, don’t go for the obvious, shallow observations. Find patterns not based on your questions, but based on the answers given.
  • Usability testing is very important, because you cannot see the flaws in your logic of thinking.

I look forward to being able to work on my next project with these pointers in mind.