A Consumer’s Perspective – Residential Solar with an Electric Vehicle

Recently, I wrote a blog on residential solar. In it, I mentioned that I needed at least a 6 kW system, but I installed a 7.25 kW system with 25 panels because I was considering adding an electric vehicle (EV) in the future. At the end of 2017, I leased a Honda Clarity EV.

My existing Honda Pilot will probably last forever, but it’s a gas guzzler and started to show its age, so I started looking at EVs in early 2017. I test drove quite a few makes and models and was not impressed. They were small, some were odd shaped and had little leg room (and I’m short). Most could not accommodate anyone comfortably in the back seat or be useful for a trip to Costco or Home Depot, but the lease deals were so enticing that I kept looking.

Near the end of 2017, Honda announced that it was adding the Clarity to its mix of vehicles with an impressive lease deal. The only problems were that there were no vehicles available and no one knew if and when they would get any. Who designed this program? The hybrid version was the only one available to test and I loved it. It was the complete opposite of the other cars that I had tested previously. It was spacious in the front, back seat and trunk, plus it looked and felt like a regular car. I added my name to the long wait list and crossed my fingers that I would get a call before the end of the year when the deal expired.

As a late Christmas surprise, the phone rang after dinner on Dec. 26. Three cars had just come in and I was lucky enough to snag one of them. I drove a pretty much untested, sight unseen car off the truck and back home and parked in the driveway by 9:30 p.m. Isn’t she beautiful?



The 2018 Honda Clarity EV has a lithium-ion battery with a capacity of 25.5 kWh and output of 120 kW. The range is estimated to be 90 miles on a full charge. It came with a level 1 charger that you can plug into any household outlet (120 volts), but a full charge takes about 19 hours. A level 2 charger (240 volts) takes as little as 3 to 4 hours.

Below is a graph of my energy consumption with the new edition. A Wednesday profile on Dec. 13 shown in blue and the Wednesday profile after adding the EV shown in red, plugging in around 5 p.m. Not much of a jump, but a steady bump up through the morning until I leave around 7 a.m. I have never looked closely at my daily profiles before, and the spikes between 5 p.m. and 7 p.m. turn out to be when I cook dinner with an electric cooktop and oven, and you can see how my son lives. The other little spikes between 1 a.m. and 2 a.m. on the Dec. 27 and 11:30 p.m. on Dec. 13 are when my son cooked himself a late night snack.



I have a short work commute, so even though the level 1 charger takes a long time, it worked for me. I could get away with charging once every two days. Having an EV takes a little more thought on where you are going and when you can go due to the limited 90 miles on a full charge.

For the first few months, I stayed in Tier 1 rates with my solar and electricity use, but the weather was still cool. There were two big palm trees in the front of my house that were shading some of the front panels, so in March 2018, before the top production months started, those were removed. I wouldn’t say there was a dramatic difference in production, but I suppose that it must have made some difference. Below is a graph of my kW solar production in 2017 vs. 2018.



While slow charging my EV was doable, adding a level 2 charger would relieve some unnecessary stress. A full charge could be done in 3 to 4 hours vs 19 hours. It had to be done. I still can’t jet off to Las Vegas with my driving range, but at least I can go downtown on the spur of the moment without having to worry whether I will make there and back. A level 2 charger brought a bigger jump in energy usage, but for a much shorter time. Below is a graph of a day doing a full EV charge vs a day of no charging. The increase from 10 p.m. to 5:30 a.m. is keeping my house at a frozen tundra temperature using the air conditioning.



July and August were particularly hot months in 2018. Since someone was at home the all day every day, it pushed my usage into Tier 2 for about a week. Maybe I should have taken vacations, added a few more panels or tried washing them down. The pictures below are from my weekly Energy Use reports from SDG&E at the end of July and August. On average, it costs about $6 for a full charge while on Tier 1 rates and about $12 on Tier 2.





Below are the July and August bill charges. Dipping into Tier 2 cost an extra $118.





Federal tax credits are available for purchasing an EV up to $7,500 depending on the car and in which state you reside. When you lease a car, the federal credit goes to the owner of the car, which in my case is Honda. The Clarity is a bit of an exception, as Honda is not currently allowing people to buy the EV version, and they are basically passing the savings through to the consumer with an extremely low down payment.

In California, a $2,500 Plug-In Electric Vehicle (PEV) tax credit is available through the Clean Vehicle Rebate Project (CVRP). SDG&E offered an Electric Vehicle Climate Credit (EVCC) of $500 as credit on your electric bill. I can apply for that credit every year through 2020. Plus, through the Clean Air Vehicle (CAV) program administered by the California Department of Motor Vehicles in partnership with the California Air Resources Board, an EV qualifies for a High Occupancy Vehicle (HOV) or carpool sticker for only $22.

For me, an EV makes perfect sense. I am well under the 10,000 miles allowed per year. My down payment was $1,425, including my first month payment. My monthly lease payment is $215 and insurance is an additional $90 per month. I used to spend in excess of $250 a month on gas. No oil changes are needed with an EV and there are no services due with my EV until 30,000 miles, which is when I return the car. I’m only on the hook for a few tire rotations. With the state rebate of $2,500 and the annual $500 EVCC credit on my electric bill, it’s like driving a free car. My tune up was $48 in 2017 and $258 in 2018. If I can stay out of Tier 2 during the summer months, saving the $118, that would be awesome. It’s been a great experience so far and with free charging stations popping up all over, maybe I’ll end up with a credit at the end of this year.