how much power is my charger consuming

[recumbent]

My 48 volt battery pack has a 3-amp charger and i'm trying to figure out how much to pay my strata council for electricity usage in the parking garage.

My electric bill said that i used 380-KWH of power total for one month at a cost of $28.00.

I was hopeing to give the strata no more than $60 per year, is this fair?

We only charge the batteries 7 months per year, once a day, for 4 hrs.

 

[fechter]

The charger is not 100% efficient, but if it is a half decent switching mode charger, it should be around 90%.

3amps x 48v / .9 gives around 160w.

The best way would be to actually measure it with a Wattsup meter or similar.

4 hours/day x 7 months x 160w works out to around 136.2 kWh
At your rate that works out to around $10/yr.

 

[PaulM]

A kill-a-watt meter is an inexpensive way to know exactly how much you are using. I have a similar power meter sold at Home Hardware stores that allows you to input your electricity price as well and gives you a dollar amount on how much you have used. If you are thinking $60/year, but it's only $10 as Fetcher suggested, you will pay for the meter in less than a year.

 

[dogman dan]

60 a year sounded high to me, especially for 4 hours a day. 10 bucks has to be more like it. I guesstimated my 2 amp charger at 5 cents a day, so the boss didn't care about charging my bike. Comes out to $12.50 if I rode every workday.