So, can you compete ?
As a big fan of the grand tours held in professional road cycling, I was watching a stage of the Tour de France today and wondered if I could keep up if I was allowed to participate on an electric bike. Let's start with the distance, a typical tour stage would be in the region of around 200 km or 125 miles. So the standard battery on most electric bikes will just not last the distance therefore your support car would need to have some spare batteries on board for the inevitable battery depletions you will encounter.
Now the speed, if you have watched a pro cycle race you will know that they fly past at incredible speeds, on the flat they are averaging around 26 to 28 mph and most normal cyclists wouldn't even consider it flat anyway . So a road legal electric bike would struggle and even with immense input from the riders legs you would still see the peleton disappearing up the road. However as this is a closed road race lets up the power on the motor as we strictly don't need to be road legal. A 1000 watt bike with a 48 volt system and battery will probably be able to keep up on the flat, though you are likely to need a bigger chain wheel and smaller rear cogs to really be convincing and give the motor some respite as the miles pile on.
What happens when we get to the serious mountains though?; pro-riders can still maintain an impressive 21 to 25 mph average so you might still be able to keep up but you are going to need to put a lot more power into the cranks to help the motor and your legs are going to get very tired. Your battery will also be depleting very quickly on the longer, tougher gradients.
Overall, I feel a powerful electric bike with 2 or 3 quick stops for battery changes has a chance but until someone tries it on an actual grueling tour stage as opposed to a quick blast round a track we will never know. It would be very interesting to watch though ....