Seven years ago, we started Opower with one goal in mind: to motivate everyone on Earth to save energy.

The scale of that goal is huge. Where do you even start?

Back in 2006, we started kicking around ideas, doing some back-of-the-envelope thinking, and we ended up with ... this.

We were playing around with ways that we could make energy use seem real to people. We knew that “kWh” and “Dtherm” meant nothing, and we were looking for ways to appeal to emotion in addition to reason.

It wasn’t anything fancy or pretty. And we definitely didn’t color inside the lines. But, start-ups and their vision have to begin somewhere. And from small discussions, big solutions one day come.

In a few short years, we’ve made tremendous strides. Opower has helped utilities and their customers save over 1,900 gigawatt hours of energy in 2013 — enough to power a city the size of Miami for a year.

Dan Yates is chief executive and co-founder of Opower. Alex Laskey is president and co-founder of Opower. This commentary was excerpted from a blog post April 4.