A friend of mine commented over bad sushi the other day that there isn’t enough electricity generated in North America for everyone to be driving an electric car.
A powerful statement! We’re going to examine the electric grid of Canada and the United States and discover exactly how many electric cars we could service. In order to do this, we’re going to need to really break down the numbers, make crazy assumptions, and examine a few things:
- Average miles driven per car
- Amount of electricity to charge a car to drive those miles
- Amount of electricity generated in North America
We’ll also probably take into account that people who subscribe to Time of Use pricing on electricity in suburban areas will probably charge their cars overnight, and not evenly throughout the day.
How Far Do Cars Travel in North America?
According to the latest Natural Resources Canada report, cars in Canada travel about 15,200 km’s per year. 19,876,948 vehicles up to 4.5 tonnes.
According to the US Federal Highway Administration, it’s 12,485 miles (20,000km’s). 135,399,945 million cars registered.
2707998900000 USA Car KM’s + 302129609600 Canada Car KM’s / (135,399,945 USA cars + 19,876,948 Canada Cars)
= (2707998900000 + 302129609600) / (135,399,945 + 19,876,948 )
Amount of Electricity Required to Travel ?
I think the best thing to use here is Watts per km. We’re going to do a stretch here and state that all cars use a certain amount of electricity per kilometer.
We’re going to ignore some pretty important deviations and build the best average we can using this guide:
- The cars all have the same drag profile, weight and loading, tires, etc.
- The charging method and losses will be accounted for
- The lifespan of batteries won’t be accounted for
- The speed of kilometers driven will be considered to be averaged at 100kph, without losses for start/stop , highway/city
So how much electricity is used to travel in one kilometer in a Honda Civic shaped type of car. We’re going to go about finding the answer in two ways. The first way would be to calculate Force Required to push a car like that at 100km/h for a kilometer, and then we will convert the amount of horsepower from mechanical Watts to electrical Watts, allowing for ineffeciencies, losses, and other variabilities. Nope.
Manufacturer Car Specs
The second and more simple way to determine number of Watts per km of travel will be to examine published data on the Nissan Leaf or the Mitsubishi i-Miev to see what they say about consumption for full charge and the projected mileage. I’m partial to Mitsubishi, so here goes:
According to Mitsubishi:
240V 30A outlet will charge a vehicle from empty to charged in 7 hours. = 7200Watts * 7 hours / 1000 = 50.4kWh
120V 8A power supply included will charge a vehicle from empty to charged in 22hours. = 21.12 kWh
The projected range of the vehicle varies, but averages around 160km under ideal conditions, and 48 km’s under traffic hell. Let’s call it 100kms.
Now i understand that it doesn’t always use the same amount of electricity and the full amperage during the charging cycle, but let’s say that it does.
50.4kWh/100kms = 0.504 kWh/km
Electricity Required for All Kilometres Driven
In order to replace North American km’s driven (3010128509600 km) with electricity, we will need
3010128509600 * 0.504 kWh
=1517104.7688384 GWh Giga Watt hours
=1517.1047688384 TWh Tera Watt hours
=1.517 PWh Peta Watt hours
Electricity Production in USA and Canada
Canada produced about 580.6 billion kWh in 2010. (580 TWh)
USA produced about 4,120,000,000,000 kWh in 2010. (4.12 PWh)
Combined, North America produces 4.6 PWh.
1.517 PWh Consumption / 4.6 PWh Production
Wow, we’d need a full 33% of the power grid to charge every replacement electric car.
We have enough, or do we?
Annual consumption levels leave little room for new cars.
USA 4.12 PWh produced – 3.889 PWh consumed = 0.231 PWh = 231 TWh
Canada 580 TWh produced – 504.8 TWh consumed = 75 TWh
Total Remainder for new load = 301TWh
Therefore, we only have enough juice to power the following:
Number of KMs per year
301,000,000 kWh / 0.504 Kwh/km
= 597222222 km’s
Number of Cars Driving the Average
597222222 km’s available / 19385 kms/car
That’s It! We can only handle 30,000 cars!
In North America!