Last year, some 50,000 electric vehicles were sold, most of them in California. This is good news for the California air, but not so good news for the California power grid.
Now, there is enough capacity to handle the additional load of charging electric vehicles, but not in individual neighborhoods. For example, a typical neighborhood grid in California, might have up to ten houses on it. Even at peak usage during the hot afternoon sun, when air conditioning demand is highest, one house might only draw 2kW. A Tesla Model S 85kWh owner, who installs the optional fast-charger on a dedicated line in his garage, can draw up to 20kW. On a neighborhood grid with ten houses, designed to peak at 30kW, this would overload the grid.
It’s just like in your home, while you may have an overall draw of 2kW on the main line running into the house, it’s not all on a single socket. Various circuits spread throughout the house, sot he load is spread out. Start the microwave, toaster, coffee maker, and electric grill at the same time on the same circuit, and you’ll blow a circuit breaker. No one wants to burn the house down for sake of breakfast. In the case of adding electric vehicle fast-chargers to the neighborhood grid, some upgrades will be necessary in order to prevent overloading.
Fortunately, according to some studies, many electric vehicle owners charge on regular 120V sockets, which isn’t as much of a load, and they also schedule them to charge at different times instead of just as soon as they come home from work. This kind of charging doesn’t impact the power grid as much. On the other hand, as more powerful electric vehicles chargers, such as the LII dual charger that a Tesla Model S owner might install on a dedicated line in his garage, become more popular, overloading, brownouts and blackouts also become a bigger threat.
The solution? If you don’t need to charge as soon as you get home, see if you can set your electric vehicle to be charged by the time you wake up. If you can charge on the 120V line sufficiently for the next day’s driving, maybe you don’t need to overload the grid with an LII charger. The best solution is to notify your utility provider that you’ve purchased an electric vehicle, as well as if you’re installing a fast-charger, not so they can charge you more, but so that your neighborhood power grid can be slated for the required upgrades.
Image © Tesla Motors