Formula E drivers have remarked that the Spark-Renault is a blast when they’re allowed to push the entire 200kW through the back wheels. The car becomes as frisky and as playful as a puppy, scampering about from corner to corner with its tail waggling furiously.

However, to preserve battery life and prolong the length of the races, the power must be turned down when the action starts. Only 150kW is permitted during the race; trying to haul nearly 900kg around tight, twisty tracks with that meagre power output is about as much fun as trying to wrestle a drunk seal up three flights of stairs.

Back in March, we were shown proposals for a Formula E power hike set out in a document submitted to the World Motor Sport Council. The plan was to increase the power output available to drivers in race mode: up from 150kW in season one to 170kW for season two, with a further step up to 200kW in season three (with a corresponding increase in quali mode power output to 250kW).

It’s a move that, ostensibly, would please both fans and drivers and one that had looked like it would be automatically phased in under the Formula E technical roadmap. It seems there’s a bit of debate going on behind the scenes, however.

The heart of the matter lies at the heart of the car: the battery. The unit was designed by Williams to meet specific criteria: to supply 133kW of power in race mode, support Fanboost spurts of 2.5s and run in quali trim for three consecutive 57s laps.

By the time the first race got underway, however, the battery was already operating well outside its intended performance envelope: race mode was upped to 150kW, Fanboost delivered in 5s stints and every single fastest quali lap of the season exceeded the 57s lap target (see chart).

The battery isn’t changing for season two which has created a bit of a conundrum. An increase in power might well lead to greater acceleration but would drain the battery faster. With no additional energy capacity, drivers would be forced to slow down more dramatically elsewhere to try and conserve energy, which might spoil the racing. They could turn up regen levels to try and top up their batteries mid-race but that can overheat the powertrain, stress the transmission and upset the brake balance. (Read more about the difference between energy and power here.)

Reliability will be another key factor. The first season package has had its baptism of fire and is functioning pretty well. Teams know where the limitations are. Come season two, that won’t be the case, and reliability may become more important than speed.

While some constructors believe there is up to a second per lap to gain from the revised powertrains and increased power, other modelling indicates that any gains would be marginal. With all things considered, turning up to 170kW might yield no discernible difference in lap times compared with the 150kW race mode while introducing considerably more scope for system failures.

With all the new drivetrains tethered to the same battery, there might be a noticeable difference in performance levels at Donington Park, where the wide, flowing circuit will favour teams with an outright faster package. But that could all change once we get back to Beijing in October, with its short straights, multiple chicanes and energy-intensive layout.

Comments at the Formula E website by Aguri team boss Mark Preston indicate where current thinking is: “The FIA are looking at changing the peak power especially in the race. The laps and race distance will probably be the same but we might have a higher level of power available. But you probably will only be able to use the peak power at certain times in the lap or maybe in particular phases of the race.”

One potential solution is splitting the power allowed per car. For example, Car A is the endurance car and is limited to 150kW at all times. Car B is the sprint car with a 170kW limit. To some extent, teams are already using strategies that split the race into faster and slower segments, so this concept already has precedent.

Another solution is to allow the upper limit to be used only in specific locations, such as on a main straight. Different strategies could mean that rivals end up duelling down a piece of tarmac with one restricted to 150kW and the other with 170kW available.

That might negate the effects of Fanboost, however (particularly as Fanboost is set at 180kW currently, which would only offer 10kW above the revised race mode). In the above scenarios, you could see a solution in giving Fanboost-winning drivers just one boost per race in their endurance car, with everyone having the benefit of the upper 170kW limit in the sprint car.

Whatever the decision of the FIA, FEH and the technical working group, the restrictions on power and energy output from the battery means that constructors must focus on making their motors, transmissions and software work as efficiently as possible. That will make the step up in power in season three, when a new battery is introduced, all the more dramatic on track, while ensuring that the technology developed for race cars is even more useful in external applications.