A low price Tesla is over $120,000. All modelling I have done shows that a 100% electric car just doesn't payback its cost compared to a standard petrol car in the life cycle considered (ie, 3 year replacement strategy). You'd need a life cycle way longer than that considered for a taxi to get break even, let alone payback.
Most other electric cars are just too small to use as a taxi (BMW i3, Nissan Leaf Zeo, etc).
Still too soon to consider electric cars on economic grounds. No doubt this will change fast, but not for a couple more years, imo.
CAB Price at posting:
$1.93 Sentiment: Hold Disclosure: Held