My wife and I are expecting our 2nd EV within the next month or so. I've had a Jaguar I Pace for almost 3 years, and love it! The new arrival is a BMW i4. I'm looking for guidance on expanding the charging station at home. I currently have a 32 Amp hardwired ChargePoint, which has been working well the past 3 years. What is the best way to make sure both vehicles are charged? My I Pace rarely needs more than a 10-15% top off overnight. My wife will be driving the BMW more miles per day, so the BMW will require more charging more frequently. Not a lot more, but definitely more charging on a more consistent basis. I'd like to combine energy efficiency with lower cost to purchase and install. But I'm open to other options that are better for the long term and possible sale of our home within 5 years or so. I'm a home technology geek, with smart devices all over the house, all controlled by a central Home Assistant smart home setup. I've seen a few write ups on smart chargers where you can have 2 vehicles attached at the same unit at the same time, with the ability to set rules and automations around how the energy is distributed between the cars. Are they worth it? Would I be better off just getting a second charge station installed? That seems extreme to me, since both cars combined will almost never take a full overnight to charge on a single Level 2 charger. Since the first one is hardwired, should I replace it with a new hardwired dual charging station? Or should we look at replacing the fixture and make it a plug in unit? I've been Googling terms like "adding a second ev" or variations of such, with surprisingly little info on success stories. Any help, or resources to turn to, would be greatly appreciated! Edit: bonus points for any realistic options that give me an excuse to bring solar energy into the home. Dan
For a while, we had a BMW i3-REx (18 kWh) and Tesla Model 3 (55 kWh.) Whoever got home last would move the plug to their car. The Tesla had a non-locking adapter so unplugging always worked. Until 3G went out, I could monitor and unlock the BMW. Usually I was up 3-4 hours at home which was well beyond the charging time of the smaller BMW and I would switch to the Tesla before going to bed. OPTION 1: Manual swap J1772 ($0) Make sure all cell phones have the Apps for both cars to monitor and lock/unlock cars. Leave a pair of large galoshes and hooded rain jacket by door. Love each other by sharing the single J1772. OPTION 2: Dual, current limited, EVSE ($500) Replace or augment the single NEMA 14/50 with a dual NEMA 14/50. Add a second EVSE (assumed non-collaborative,) and set both EVSE to a maximum of 20 A. Both cars will get plenty of charge over night for the next day's drive. Extra credit, split the NEMA 14/50s and EVSEs to minimize walking around cars. OPTION n: HOLD MY BEER! Watch this!! These options should be discussed at a bar with pen and napkins. Bob Wilson
InsideEVs has an article about that (although published in 2019): How To Charge Two Electric Cars At Home
The first electrician just showed up saying I need a second 40amp circuit, and he had no knowledge of technology to manage/balance current on a single circuit. He also insisted that the charging station is unique for each vehicle. I asked if I could buy the new station through them, or if they recommend specific models. That's when he said, "Oh no. The charger is completely different depending on the model of the car." Ah, ok. You're not giving me warm fuzzies about working with you.
Perhaps the electrician heard that Teslas have their own unique charging stations. This ClipperCreek Share2 pair of 40-Amp EVSEs share the same 50-Amp line. The pair costs $1710, which isn't cheap, at $855/EVSE. If you already have a 40-Amp line and an EVSE, perhaps the 2nd 40-Amp line and a more reasonably priced EVSE would be less expensive than the Share2 system. One thing surprised me on ClipperCreek's Share2 page: Mounting 2 EVSEs right next to each other in a corner might make it tough to charge 2 EVs at once.
Thanks for the info. I'll check into the Clipper Creek. Is it at all feasible/advisable to run a dual charger off one 40A circuit? Should I continue with hardwired options, or get more flexibility by having 2 NEMA 14/50 receptacles installed? Yeah, I'm pretty sure the electrician wasn't really all that interested. He insisted that there was not a way to combine 2 chargers on a single circuit. It may well be more expensive than a second circuit (I'm skeptical), but he left the impression he didn't really understand the situation. I know just enough to be dangerous, which is why I want a pro. I'd like to feel secure that the installer has more knowledge about this stuff than me.
ClipperCreek also offers their $1,566 Share2 Enabled HCS-40 EVSE Bundle, that includes 2 x 32-Amp EVSEs that can share a 40A line. I've been charging with a used 48-Amp commercial-model ClipperCreek EVSE for years and it's been trouble-free.
I would just do a manual changeover. At least try it to see if it works for you. It sounds like you can just alternate which car gets plugged in every night
A number of EVSE manufacturers make dual-charging EVSEs in addition to Clipper Creek, such as the Grizzl-E Duo. They generally split the power between the charging cables so you don't have to worry about extra power draw, but you do get lower charging rate if you're charging two vehicles simultaneously. That's how it generally works at commercial sites as well.
