After going through our various protocols in the first part of our Supertest, dedicated in particular to consumption, the Renault Megane e-Tech now reveals its secrets in terms of charging. Promising on paper, it ultimately remains average.
In order to shed light on electric cars and their consumption, we decided to carry out real-scale tests, in which each model studied covered almost 2,000 km. An opportunity to measure the autonomy on long journeys on the highway, but also the mixed consumption and charging performances at the fast terminals. For this we have implemented a strict protocol for each car.
Super tests for electric cars
our complete test protocol
Charging curves for the electric Renault Megane: A “useful” full tank in 37 minutes
Modeled after the Volkswagen ID.3, its natural competitor, the Renault Megane e-Tech, at the top of the range, has a system capable of absorbing 130 kW of peak power. Which she almost did in our two different tests very fast with 128 kW power. Unfortunately, the celebrations don’t last as the power drops to 106kW before plateauing very slightly and then starting an almost linear fall until the end of the charge. Therefore, in order to be able to use the advertised maximum performance, the battery must be tickled at the bottom and connected at a rate below 15%.
It doesn’t get much better than the excellent navigation provided by Google Maps with the battery warm-up function. But it’s up to 25% where gains are felt before the curve reaches its previously observed level. Not enough to notice a real difference as it only results in a 10-80% gain in exercise in one minute.
At the fast terminals the Renault Megane e-Tech reached the 10-80% in 37 minutes. According to the various end devices tested, this is an average of almost 46 kWh recuperated, or 42 kWh depending on the announced net capacity of the battery. The end of the charge from 80% to 100% is also long as it takes another 38 minutes, even if reaching 90% takes only 10 minutes more. Needless to say, the operation is not profitable both financially and in terms of time. Especially since this 20% is consumed twice as fast on the motorway, in just over 20 minutes or 45 km.
|Load time (minutes)||37||38||75 (1h15)|
|Autonomy gained (km)||170||48||218|
Recovered autonomy: 275 km in one hour for the Megane e-Tech
By crossing this data with the consumption values noted previously, the electric Renault Megane can therefore regain almost 170 km of autonomy in 37 minutes. This is a far cry from the 250 km in 25 minutes stated in the prospectus, since it is based on the WLTP values. Except that when you connect to a fast terminal, it’s usually on the highway. And this is where the appetite comes in.
In terms of prediction, the system is always reassuring. Admittedly, by the way, the display takes into account the last 75 kilometers of rolling, which is rather average without being overly optimistic. But beware if relief sets in. On the contrary, at the end of the charge, the autonomy indicated is always pessimistic, giving the impression that the average that previously served as a base is increased by 4 kWh/100km. In short, this SoC/autonomy ratio means you’re never caught off guard.
How much does it cost to charge the electric Renault Megane?
At full rate on Ionity, charging from 10-80% could cost €29.23 (€0.79/min excluding operator fees). At Fastned, which prefers billing by consumed energy, the same operation would cost €26.86 (€0.59/kWh excluding operator fees). Rule of three that would represent the Mégane’s cost price on the motorway at legal speeds between two stations, as in our case, average €16.5/100 km.
On this trip we made three top-ups for a total of €56.06 excluding operator fees. That’s a final cost of €13.03/100 km at our last stop on the journey (430 km away). The overall budget reduction therefore depends on the charging solution chosen to return to the starting SoC, here 80%.
Onboard route planner, ABRP and ChargeMap: Draw
To travel with peace of mind by electric car, it is essential to prepare for the journey. This is what the on-board route planners and mobile applications for automation offer you, in order to show you the route and the journey time, but above all the different stations for charging and the expected charging time.
Based on Google’s excellent navigation, the Renault Megane offers its own planner. Surprisingly he chose an unexpected route to reach Porte d’Orléans in Paris, our finish line which took us through the National 7 before investigating on the A77. According to him, it’s a 20 km shortcut that continues past a secondary road where consumption is low. However, there is then no choice but to connect to a 50kW DC terminal, increasing the downtime to a total of 1h35. It can be smart in the north-south direction (where we encountered complications on the A6), but not in the other, where the fast terminals are not lacking.
On the A Better Route Planner side, the route is more common and logical. We didn’t change any parameters other than selecting the appropriate vehicle, the actual charge rate at the start, and an arbitrary 20% charge rate at the finish. In the end, this one asks us to stop only at Ionity terminals for a total of 41 minutes of charging and 4h34 of travel, so a total of 5h15. The chargemap planner even makes different decisions with a Fastned station, an Ionity station and a Total Energy station. Advantage here in terms of prediction as we are never asked to go beyond the 80% mark beyond which the operation is not profitable. According to him, this ride requires 5h08 of driving, including 47 minutes of recharging.
Given the network of terminals on this route, we decide to leave with 80% charge. Sufficient to reach the -beautiful- Fastned train station of Saint-Ambreuil, which is the farthest from our starting point. By reloading what is just necessary to arrive at the next station, we remain immobilized for 28 minutes. That’s a minute less than at the Ionity station in Maison-Dieu, almost 130 km away. Our final charge serves as a supplement to meet our goal of 13 more minutes to unplug at 45% charge.
In the end, our strategy translates into a driving time of 4h21 and 1h10 to recharge, for a total gross time of 5h31. By adding a flat rate of 4 minutes in stages (any time to enter and exit the area and to connect the car), our journey corresponds to 5h43 for 500 km.
Note here that A Better Route Planner is dead wrong on certain cooldowns: according to him, it takes 16 minutes to go from 52% to 91%, when in reality it takes more than twice that! A little closer to reality, if still a little optimistic, Chargemap is getting closer to the times we’ve been observing. But he fails in choosing terminals as he recommended us to aim for the 160kW SDEY terminal at exit 22 which has been declared out of service and is 4.5km further than Ionity Maison-Dieu!
At the end of this detailed chapter, let’s also specify that by forcing the navigation of the Renault Megane, it was planned to arrive at the Fastned station at a rate of 18%, and often realistic, with the predictions 10% certainly at the beginning were high but became more sophisticated as the miles went on.