As an EV owner, thinking consciously about my consumption is important to me both in terms of cost and in order to support the transition to cleaner vehicles. And I was recently inspired to think more about my own energy use at home.

My provider, Octopus Energy, offer a number of things that we make use of:

  • 100% renewable energy across all tariffs, which is a good starting point!
  • Innovative tariffs like Octopus Go, which is designed for EVs and provides four hours of lower cost energy between 00:30 and 04:30 every day (for me, that’s 9.50p/kWh vs 31.21p/kWh). This incentivises usage away from peak times, balancing load on the grid and reducing the need for fossil fuels to support heavy demand.
  • Excellent access to data, both through APIs (which I use with an iOS shortcut to get the next day’s gas rate) and the Home Mini, which feeds minute-by-minute usage into my app.

Day-to-day, we try to maximise usage of off-peak hours by scheduling the car to charge during that period, and by using the timers on the dishwasher and washing machine so they run overnight too.

But what impact is this actually having?

I downloaded all 19,250 rows of my usage data from 4th June 2022 to 10th July 2023. Here are five quick things I learned:

  • On average, 47% of our entire energy usage occurs within the four off-peak hours. Even better, that contributes just 22% of the cost of our total bill.
  • Across the year, off-peak use ranges from 40% to 57% of total. A higher off-peak proportion seems to be driven by lower peak hours use, highlighting the importance of lowering total consumption as well as time-shifting.
  • Our highest total usage is on Mondays and Tuesdays, and lowest on a Thursday. I don’t think it’s a coincidence that Thursday is when I most often travel to the office.
  • During the day, outside of the off-peak spike, I can identify patterns in our daily routine like getting up, making lunch and dinner, and going to bed again. It’s easy to imagine the wider grid impact of the evening peak across all households.
  • While this hourly pattern is similar across the year during peak hours, there’s more variation during off-peak. This is likely influenced by weather and driving habits: EV batteries last longer during warmer weather and we may not have needed to charge as often.

Having access to this data has been interesting, but it’s also given me confidence that the things we’re doing to manage our energy usage are having some impact. But I’m sure there’s lots more we could do!

Industry has a critical role to play to innovate with customer propositions and further open up access to API data. But as consumers, we also have a responsibility to use what’s available. Together, the potential is huge.