It's a question I still ask myself today: we know that there is an impact on driving habits, and therefore on the use of regenerative braking. But how can we plan for this impact, given that it varies from driver to driver, from journey to journey, and from day to day? When calculating energy consumption per 100 kilometers driven, should we include or exclude regenerated energy from the total energy consumed? Here's why these questions are important, and why it's crucial to understand the data that's increasingly being shared with you.
This week, I was working on a dashboard for a project. The aim of this project is to share test data under real-life conditions in Quebec. So I need to make sure that the data is reliable and rigorous. By examining and comparing my data, I noticed a huge difference: for one month's use, I had a difference of 20 kWh/100 km for the same vehicle.
On further investigation, I realized that my comparison excluded regenerated energy from the calculation. So, if I make a 100 km journey where 60 kWh were consumed and I regenerated 10 kWh during the journey, according to my calculation, I have a consumption of 60 kWh/100 km, but according to my reference, we have a consumption of 50 kWh/100 km.
At first glance, you might think I'm right. But let's take a step back.
Let's say we look at this from an economic perspective. If we're drawing up budgets and need to estimate energy costs for transport next year, we look at consumption per 100 km and apply it to the projected mileage based on next year's operations. How do you calculate the energy recovered by regenerative braking? Since it's variable, you have to apply it by route and use. In the example above, in reality, my operating cost is 50 kWh/100 km, because I didn't pay for the 10 kWh regenerated during the trip.
Now let's look at the operational perspective. I plan my routes. Now that I've electrified my fleet of vehicles, I have to take into account the distance travelled to avoid breakdowns. If I rely on calculations without including regenerated energy, I run the risk of running out of range. If my driver doesn't have good driving habits, if there's less traffic than usual, or if the regeneration is faulty on the vehicle, etc., I run the risk of running out of range. Service reliability is essential for a carrier. But on the other hand, electric vehicles cost more, and to make them profitable, I need to use them on the longest possible routes to generate maximum savings.
In my opinion, both methods are valid, but it's essential to fully understand the data before forming an opinion. This is just one example of how misinterpretation can lead to problems and dissatisfaction. It's often said that numbers can be made to say anything, and I tend to agree. In recent years, we've been increasingly confronted with “fake news”, and I believe it's the responsibility of all of us to understand the subject, to take the time to understand the logic applied to the figures we're given before making a decision. On that note, I think I'll share both types of data in my dashboard as they are both important.
