I'm now using my little moped to commute to work. It's about 5km each way so I have to recharge at work in order to get home. Luckily, there's a power outlet near the bike rack. Unfortunately with the little 1.5 amp charger I have, it takes about 6 hours to fully recharge so I'm stuck if I need to go back at lunch time.
I was curious how much juice it took to recharge my bike so I put my Kill-a-Watt on it while I charged it up overnight. The 36 volt SLA battery charger consumed 300 watt-hours (0.3 kWh) to bring me from pretty much zero to full charge.*
* The engine consumes 150 watt-hours for a full run but the batteries need 300 watt-hours to top up because of inefficiencies in charging / depleting.
At 12 cents a kilo-watt-hour in Connecticut, that's about 4 cents for a full charge, each way. Or about 8 cents a day.
Or $1.60 a month. Of which, I'm only paying 80 cents and mooching 80 cents off my workplace. Shhh.... don't tell anyone or they'll dock my salary!