As EVs multiply, it’s critical for electric utilities to manage their energy needs. For that they need data on EV owners’ charging habits, and Opower has it. Opower claims to be the world’s largest energy data storehouse, covering 75 utility partners and 50 million households.

The Outlier blog crunches that data into digestible articles about how people are using energy. A recent installment looked at the usage behavior of EV owners who charge their cars at night, based on data from about 2,000 households in the western US.

Some of the findings are unsurprising: plug-in peoples’ electric use spikes at midnight, because that’s when they charge their EVs. All the EV owners considered in Outlier’s analysis have signed up with their local utilities to get highly discounted electricity between midnight and 7 am. After midnight, EV owners’ electricity use can rise to four times the average level.

More surprising is the fact that EV rate plan subscribers tend to use more juice than other consumers – and it’s not because of their EVs. Between 7am and midnight, they use an average of 21% more electricity than the typical single-family household. The reason: EV owners tend to have bigger homes and more power-hungry goodies, such as swimming pools.

Outlier also found that people who go electric also tend to go solar. A recent survey of utility customers found that 32% of EV owners had installed rooftop solar, which drastically reduces their grid power usage during the middle of the day. When you add it all up, EV/solar households use a little less juice from the grid than the typical utility customer.

Source: Opower
Image: Jurvetson/Flickr