If we want to add a 240 outlet, could we? And is there a concern that line to the house could support it?
Easily. As noted, 200A service is quite sufficient for an awful lot, especially now that most lighting has moved to CF/LED - the load calculations (I'll touch on these more later but they're a particularly absurd brand of nonsense math) are based on things that have no basis in reality. You should be more than fine to add an EV charger without hitting any limits. The line to the house will be designed for 200A service, and you'll probably have around 25kVA of service (either your own transformer or shared capacity), which is around 100A continuous. Those transformers can run over-rated for a long while on thermal inertia before having any issues, and you shouldn't have any issues at all with adding a 50A circuit or two - though you don't really need it, you may as well run it.
You can service most practical EV/PHEV driving on a 20A/240V circuit. This will give you 16A continuous current (80% of the rating), 3.8kW of charging, and about 10 miles per hour of charging - an 8h overnight charge will net you most of 100 miles. If you have a long range BEV, if this doesn't recharge you and you drive like a normal person, you'll be "full enough for regular use," and if you have a PHEV, you'll both be entirely full and not care in the slightest about being a hair less than full.
However, if you're going to run a new circuit, which it sounds like you need to do, run a 50A circuit and put a 14-50 outlet in (standard oven/dryer plug). This will let you charge at 40A (which most cars won't do), but, IMO, it's
more useful than the 60A/48A hardwired charger, because if you find other things you want to do with the garage, or if you're selling the house to someone else at some point, a 50A outlet is useful for a wide variety of things. You can run a workshop off a 50A outlet, you can't run a workshop off a hardwired EVSE - and the number of cars that can charge at 48A vs 40A is so slim as to not matter, and the practical difference in terms of charging is meaningless unless you're running a taxi service or something. 40A will get you 9600W, or about around 35 miles per hour of charging (270 miles in 8 hours), 48A will get you 11.5kW charging, 40 miles per hour, 322 miles in 8 hours. And very, very few cars can charge up that fast anyway.
Dropping an outlet off a spare breaker wouldn't be hard either, and 30A (24A continuous) is plenty for most charging too - if it's a surface mounted box, I'd personally be inclined to just run a 30A twist lock outlet in a small box attached to the panel and not bother anyone with permits, but... up to you.
They make chargers with two plugs that wire into a single 40amp/240v circuit. When both cars are plugged in the charger sends 16amps to each (still plenty to add 100+ miles of range overnight). When one car’s battery is full (or when only one is plugged in) the charger sends the full 32a to that car, doubling* the charging speed
And, importantly, more recent NECs explicitly allow this sort of load sharing of EVSEs. If you have two EVs, unless your goal is waving around how much cash you have (at which point the cost of wiring doesn't matter, you've got His and Hers Tesla Model S Performance Editions, you know you got charged the Tesla Tax for upgrading your panel to charge them both at full speed, and you don't care), this sort of paired charging system makes a lot of sense. It covers the common case and most of the edge cases very well, though if you both are traveling salesmen doing 300 miles a day on your 320 mile range vehicles, you might need to pay for the upgrades. If you drive an average 30-40 miles a day, it just doesn't matter.
Do you actually need a charger? Most EVs add about 4 miles of range for every hour they're plugged into a plain old 120V outlet. So a typical 10hr overnight charge should add back about 40 miles every night. That's plenty for a PHEV, and might be enough for a regular BEV too.
240V charging is nice, but may be more of a "want" than a "need". Especially if you just end up with a PHEV.
Having run a PHEV on 120V charging for a year and a half before rewiring a few things, lopping off some extension cord ends, and charging on 240V, I agree that it's sort of doable, but the difference between 120V and 208V/240V charging is enough to justify the 240V, even if you're only going to run 20A. Numbers are from a Gen 1 Volt, adjust as needed.
The major problem with 120V charging is winter. First, you're going to be using more energy per mile because you have heating loads. I can get 4 miles per kWh out of the Volt in the summer, and in the dead of winter (if it's not using the engine for heat), it's closer to 2 miles per kWh. We had a run recently with some exceedingly nasty headwinds and crosswinds that was also around 2 miles per kWh. So you need to charge more in the winter - but most EVs will also have a pack heater, because charging a cold battery pack can't be done safely. Throw a kW or so into a pack heater for a while, and that 1440W of charging gets an awful lot smaller, in a hurry. I'm not aware of any EV that will pull >12A on 120V without some odd heroics (better spent wiring up 240V), because of 15A circuits being a thing. It's possible, it's better than nothing, but it's not a great solution.
The second problem, and perhaps this is more of our issue because my wife doesn't work, is "recovering from multiple trips a day." When we were charging on 120V, if she made a town trip early in the day, we were only partly charged by evening if we had something else going on - which meant either using gas, or "charging while out." I carry some nice extension cords and have charged from many people's garages, but with 240V charging, it's not been an issue because it recovers so much faster. A long range BEV might not have the same issues, but we've had the occasional three trip, 100+ mile days, with a ~35 mile range on battery Volt, using zero gas at all. Those aren't possible on 120V - but with 240V, it's not an issue.
So, worst case, hack a 120V circuit into a 240V circuit and charge from that. You'll get 240V/16A instead of 120V/12A, and the difference between the two is very noticeable. Again, we did the 120V/12A charging for over a year before I changed things around, and I wish I'd done so earlier.
You're almost certainly fine, but and electrician should run a load calculation before installing. It partly depends on what you're installing.
No, you shouldn't. You'll "prove" your home needs to be upgraded to 300A service, for about $10k in electrical work, plus $5k-$10k to the power company, despite your house never having pulled more than 100A at any single point in time. It's a wonderful bit of nonsense math that no longer, in any way, reflects reality. IMNSHO.
The main problem NEC load calculations, as far as I'm concerned, is the "lighting and general loads" calculation. Our 2000 square foot home "needs" 6000W of lighting, because we have the standard screw type sockets. Never mind that we have LEDs everywhere and 6000W is a good fraction of our peak loads period (I've seen 12kW peak, so 50A at 240V... on 200A service... when load calculations claim we "need" 200A service...). But, because someone could swap incandescents in everywhere, that's what the numbers say, and so I end up with comically over-provisioned service. If I put a 50A EV charger into the math, I'm fairly certain it would show that we "need" 250A service, a service upgrade, etc. I'd drop $20k into the upgrade if it were even possible (we have a combined meter and outdoor load center that literally can't be bought for any money anymore - a friend needs one for a solar install and can't get it). But it's absolute nonsense math, and isn't a safety issue either, because the breakers protect the wiring. The logic behind the load calculations, far as I can tell, is that if someone gets a bunch of nuisance trips, they'll bypass something, but it's just not a real worry with modern breakers (they trip even if held over), and it doesn't reflect modern reality.
Just install the circuit, and if someone is hemming and hawing about a load calculation, go find another electrician or do the work yourself. Again, IMO.
If you have to run new cable anyway, I would run a 60 amp breaker so you can do a hard-wired 48 amp charger (e.g. https://www.chargepoint.com/drivers/home).
Ugh. Don't give ChargePoint money. They build very, very good hardware. They test it wonderfully, and it will withstand all sorts of crazy environmental conditions. I just can't
stand their business model, which is "You must recover costs for power delivered, which means you need revenue grade metering equipment, which we provide for obscene amounts of money, and, gosh, look at the monthly service fees you need to pay us to manage it!"
For a lot of places, they could literally give away power for charging and still come in less than ChargePoint's monthly costs, and that's without getting into the cost of the hardware. Again, wonderful hardware, 0.5% accuracy on their metering, just a business model I find actively toxic and opposed to EV penetration for anyone other than the "His and Hers Teslas, doesn't care about money" group. I've
never used a ChargePoint charger, because the rates people want to try to recover their costs on it (with that whole monthly fee and nobody using them problem, power rates tend very, very high), it's far cheaper for me to run some gas,
and buy carbon offsets, than to pay to charge at one of those stations. That they're often pay by the hour and I only have a 3.3kW onboard charger doesn't help things...
Now: PHEVs.
Do not buy a PHEV. You negate all of the benefits of going fully EV. Two systems to maintain etc.
In the words of Wikipedia, [Citation Needed]. Preferably an X, I love that someone seems to have found some spare DC-9 engine nacelles and stuck them on a bizjet. My understanding is that it's been supersonic a number of times during testing, and it may very well be capable of supercruise, were you to let it run past the barber pole... and work out the trim issues.
PHEVs have been out for over a decade now. The various reviews, studies, consumer data collection, etc, all demonstrate that they are, in terms of maintenance costs, lifetime carbon emissions, etc, comfortably within the error bars of the pure EVs. The argument that they are "so complex, two systems, so many things to fail!" simply hasn't shown up in any actual data one can find. And, further, we have twenty years of data on hybrids (the Prius and various others), which are exactly the same thing - "two systems." What the data seems to find rather reliably is that the hybrids require less maintenance than an ICE, and that the "added complexity" people are worried about doesn't seem to lead to any problems with reliability. A PHEV is, functionally, just a "super hybrid" with a charger added on, and the operational numbers show that.
So, if you're going to trot out that ancient bit of anti-PHEV "wisdom," at least find some sources that back your argument. They're not a new nor novel technology at this point, and the data is in. They work just fine.
I can back my claim with Consumer Reports data from 2020:
https://advocacy.consumerreports.org/wp-content/uploads/2020/09/Maintenance-Cost-White-Paper-9.24.20-1.pdf, in which BEVs and PHEVs have virtually identical maintenance costs, both being about half the cost of ICEs. And various BEVs don't manage to score so well in reliability scores - before you get into the assorted "LG builds skateboards for companies, and apparently can't build big batteries..." problem that has impacted a variety of manufacturers. The PHEV battery banks are fairly low stress and low density compared to BEVs, so don't seem to have any real issues with stressing the chemistry and bursting into flames. I'm optimistic that set of problems will get solved, but the reality right now is that the PHEVs are boring vehicles that cost about the same to run and maintain as a BEV. I've provided one such report, and can find a variety of others. If they're really that unreliable and complex, you ought to have no trouble finding studies that demonstrate that they actually cost more to keep running, but I don't think you will.
As someone else pointed out, and I've pointed out in a variety of places over the years, they also have the nice perk of using 1/4 to 1/6th the cells of a long range BEV, meaning that on the currently battery limited production lines, you can replace an awful lot more gas miles with PHEVs than pure BEVs, because they're not carrying around a huge pack for the edge case. They use the well proven and reliably produced ICE technology for that.
I'm planning on moving to Maine this summer and also trading out our car for an electric. I was thinking of getting a BEV, but you may have convinced me that a PHEV may be more reasonable.
Get a Gen 1 Volt if your typical daily driving is under 25 miles, get a Gen 2 Volt if you have longer range needs, or if you want to buy new, get a Rav 4 PHEV. Done.
A question though is what are the lifetime maintenance cost differences between the two? BEV's are much simpler engine wise, don't require oil changes, etc. But on long trips, you end up having to leave them at home and rent. (unless you have a long-distance 50k Tesla).
See above. The maintenance costs, if you ignore the Jaguar-reliability Teslas (that's not a complement), are about the same. And, in the deal, you can drive cross country with them without having to do anything else.
If I'm allowed to link some long form writing I've done on my personal site on the topic (if I get banned for doing so, whatever... less internet is better, I suppose), I've written a number of blog posts on this topic:
https://www.sevarg.net/2019/07/07/i-bought-used-chevy-volt-and-you-should-too/https://www.sevarg.net/2020/04/27/slow-dumb-charging-quit-charging-for-ev/https://www.sevarg.net/2021/12/04/family-trips-2600-miles-in-a-volt/
