This past weekend I spent some time with the family at my sister and brother-in-law's place where we charged the car using 240 VAC for the first time. I made an adapter to plug into a standard 240 VAC Household Dryer socket since Eric and I judged that the available 120 VAC circuits were already quite loaded and we did not want to overload them and risk blowing fuses. Getting to the dryer socket was very easy as most dryers are very light and easy to move in order to get behind them to access the plug. The charging time at 240 VAC was approximately 3.5 hours compared to 4.5 hours using 120 VAC for a typical commute (42 KM).
To accurately measure the actual energy consumed when charging at 120 VAC, I also decided to use an energy meter that I had purchased a while back. I was a little surprised to discover that the charger was drawing more power than I initially thought. At the beginning of the charge cycle, the charger gradually but quickly comes up to it's maximum power consumption of 2300 watts which would exceed a standard 15 amp circuit of approximately 1800 watts.
Here are a few shots of the energy meter's display at various intervals during the four hour charge cycle:
4:20 into the charge cycle and consuming 2234 watts (pack <80%)
21:07 into the charge cycle and consuming 2298 watts (pack <80%)
37:28 into the charge cycle and consuming 2298 watts (pack <80%)
1:57:08 into the charge cycle and consuming 2220 watts (pack <80%)
2:55:43 into the charge cycle and consuming 2245 watts (pack <80%)
3:50:05 into the charge cycle and consuming 540 watts (pack >80%)
4:06:45 into the charge cycle and consuming 540 watts (pack >80%)
4:08:08 into the charge cycle and consuming 21 watts (pack 100%)
The maximum power consumption measured by the energy meter was 2318 watts and the total cost of the energy consumed was $0.688 ($0.08 per kilowatt hour x 8.6 KW).
To conclude, my initial estimate a few weeks ago was only off by about five cents on the total cost of energy consumed for a commute of 39 kilometers. Based on the energy meter measurements, the actual cost per kilometer driven is 1.76 cents.
$0.688 / 39 kilometers (24 miles) = $0.0176 per kilometer ($0.0286 per mile)
Energy Meter sold at Canadian Tire
In the news
9 years ago