My Oceanside, California, NextDoor neighborhood website has a constant thread of questions and answers about electric cars and installing solar power. These posts are a fascinating read on how people are increasingly investing in electric vehicles (EVs) and rooftop solar power to save money.
One common thread involves experienced EV drivers sharing money-saving best practices with new buyers. They point EV newbies to San Diego Gas and Electric and their special EV recharging rate called EV-TOU. Under this rate structure a customer pays a monthly $16 fee. For this fixed monthly payment that customer can recharge their EV during a Super-Off-Peak time period between midnight and 6 am on weekdays and midnight to 2 pm on weekends when the price of electricity is only 9 cents per kWh. This price is a third or more less expensive than charging at a recharging station where prices can be 28 cents per kWh or more.
Often a newbie EV buyer will respond with a question on how to recharge an EV when they are sleeping. You can almost sense the Tesla owners grinning over their answers. Recharging a Tesla is as easy as setting an alarm clock on a smart phone. Using the Tesla phone app or the vehicle’s touch screen, an EV owner can set recharging time periods. After setting the recharging time it is just a matter of plug and play—the Tesla owner plugs the EV into the electrical system and the car automatically recharges during the EV-TOU time period. To get faster recharging times, Tesla sells a home recharging station that costs $500 plus about $150 for an electrician to hook it up to a home’s electrical panel. This investment insures the EV will reach its 80% of optimum battery charge level within the EV-TOU time period.
At 9 cents per kWh an EV can cost a fourth as much to fuel as a gasoline powered car. For example, assume you drive 1,000 miles per month in urban traffic. For EVs the rule of thumb is that they get 4 miles for every kWh of electricity consumed. So in this example the EV would require 250 kWh during a month of driving. If recharged using the Super-Off-Peak rate of 9 cents per kWh then the monthly electricity cost is $22.50 plus the $16 monthly charge or a total of $38.50. For a gasoline powered car that achieves 20 miles per gallon at an average of $3 per gallon gasoline price in California the car’s fuel costs would be $150. In this example, not atypical for California, the EV saves its owner $111.50 per month in fuel costs.
EV cost advantage really becomes insurmountable compared to gasoline fueled cars when the vehicles are fueled from a home’s solar power system. Most home solar systems are sized to satisfy air conditioning demand. That means there is a lot of solar electricity available for other applications when the AC is not running. My city’s NextDoor posts are filled with solar home owners explaining how they fuel their EVs for free. From their perspective they bought their solar system to lower their electricity bill while still enjoying 72-degree air conditioning at zero emissions. The added electricity consumption off their solar system to recharge their EV is at zero incremental cost.
Increasingly, many solar home owners are posting about converting their natural gas water heaters and stoves to electric to capture the same zero incremental energy cost savings they enjoy from using an EV. California has adopted net zero emissions building codes for new residential homes that result in new homes having rooftop solar running a totally electric house. The growing consumer awareness of how much money can be saved by going solar in a totally electric home is fueling a growing remodeling trend for existing homes.
Businesses are beginning to join homeowners in reengineering their buildings and fleets to save money by becoming zero emission entities. Amazon is an example. They have committed to using 100% renewable energy by 2030. They are buying 100,000 electric delivery vehicles, with the first 10,000 scheduled to be on the road by 2022. Connecting the dots, Amazon always embraced a least cost business strategy. Their investments in renewable energy and EVs represent their newest technology path for continuing this strategy.
For me, I saw the future as I waited for the light to change while riding my mountain bike along the Coastal Highway. At the light were the new mid-engine Corvette and a Tesla 3. Both represented the pinnacle of their automotive technologies. Guess which one smoked the other off the line? Can’t beat acceleration at the speed of electrons! And increasingly, you can’t beat electrons on least cost.