Here’s What You Need To Charge Your Electric Car At Home

DEC 20 2018 BY JIM GORZELANY 46

HERE’S WHAT YOU’LL NEED TO KEEP YOUR ELECTRIC VEHICLE FULLY CHARGED AND READY TO ROLL.

With the nation’s network of public electric vehicle charging facilities still relatively thin, most EV owners charge their rides at home. This can be as easy to accomplish as plugging the car into a wall outlet or as complex as having solar panels installed to replenish an EV’s battery.

All EVs come with a means to be connected to the power grid. Technically speaking, the charging station that converts AC house current into DC electricity is built into the vehicle. Most models include a basic 110-volt charging unit that plugs into a standard electric outlet via a conventional three-prong plug.

This is called Level 1 charging, and assuming you already have basic electric service in your garage, it’s the cheapest way to go. Unfortunately, it’s also the slowest. Depending on the vehicle and its battery capacity, it can take anywhere from eight to nearly 24 hours to bring its power cells up to a full charge.

A better choice is to spend a few hundred dollars to have an electrician install a dedicated 240-volt circuit – like those used for an electric clothes dryer – to take advantage of what’s called Level 2 charging. This can replenish a depleted battery in around four hours. You’ll also need to purchase an external Level 2 charging unit, which is also called the electric vehicle service equipment (EVSE).

Level 2 charging systems come in two basic varieties, plug-in portable and wall-mounted units that are hard-wired directly to a home’s electric service. If you don’t have a closed garage and you’ll be charging the vehicle outside, local codes may require a fixed-mount unit. Otherwise a portable charger requires no professional installation, assuming you’ve added the 240-volt service line. This type can come in handy if you own two homes or will be staying with friends or family in another town and want to take the unit along for charging at your destination.

A good quality EVSE can cost between $300 and around $1,200. If you’re choosing a wall-mounted unit, expect to pay another several hundred dollars for installation, depending on local labor rates and permit costs.

If you’re buying an EV, make sure the power outlet or wall-mounted charging station will be located within close proximity to your vehicle’s connecting port. Charger cables usually run from around 15 to 25 feet in length, but that may not be sufficient or desirable if the car’s port is located on the opposite end of the garage from the available power source. You may have to have an electrician extend the service closer to your car’s charging port if that’s the case.

SHOULD YOU GO SOLAR?

It’s possible to use solar power to charge an EV, usually via panels mounted to the garage roof, but this can cost upwards of $7,000 per installation. And that doesn’t include having a storage battery installed to capture power during daylight hours for overnight charging, which could double the cost.

Solar charging becomes more cost effective, however, if you’re tapping into a full-house power system. Sources suggest a properly sized whole-house solar system can pay for itself in around seven years, depending on the size of the installation, local labor rates, component costs, and other variables. The national average for a 6-kW home solar power system is reportedly close to $19,000. Fortunately there’s a 30 percent federal tax credit with no limit available to help offset the costs. Unfortunately, the solar-power credit is scheduled to drop to 26 percent in 2020, 22 percent in 2021, and will be discontinued altogether in 2022.

CHOOSING A CHARGING STATION

Popular brands of EVSEs include ClipperCreek (one of the first companies to get into the home changing business), Siemens, JuiceBox, AeroVironment, and ChargePoint, among others. An online search can help you find a unit that comes with the features and power output that meets both your needs and budget. To make matters easier, you can purchase either of three popular ClipperCreek charging units directly from MyEV.com. Coming in both portable and hard-wired configurations, they’re priced between $379 and $565. Each of our EV for sale listings features them under a “shop for chargers” tab, or can check them out via this link.

Experts suggest buying an EVSE that can produce at least 30 amps of power. Generally speaking this type of unit would be able to add around 30 miles of operating range to a given battery pack per hour. Some EVs can get along with fewer amps, but buying more capability than you may need today makes the installation “future proof” should you eventually trade in the vehicle for a model that can handle the added capacity. However, if you’re planning on using a 30-amp unit you may need to upgrade the line’s circuit breaker to one that’s rated for at least 40 amps.

As with many other types of electronic devices these days, you can buy a “smart” EV charging unit that includes Wi-Fi connectivity. While this adds cost and complexity to what’s otherwise a plug-and-play device, choosing a smart charger adds a layer of convenience. These units allow an owner to use his or her smartphone to monitor charging, and how much energy the vehicle is using to help gauge running costs. Some smart chargers can communicate with your power company to only charge at off-peak times for discounted rates, and even receive commands via Amazon’s Alexa virtual assistant.

Finally, only consider charging units that have been tested and certified for safety by an independent source like Underwriters Laboratory (UL). And if you’re having a charger installed outdoors, make sure it’s rated for that purpose.

Source: MYEV.com

Categories: Charging

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46 Comments on "Here’s What You Need To Charge Your Electric Car At Home"

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I think implying people need L2 charging at home to own a BEV is doing a disservice to BEV adoption. While the chargers themselves aren’t expensive getting the electrical work done can be very expensive especially if one’s current electrical panel is maxed out and/or far away from where the charger will be connected. This might be a deterrent at least at the lower end of the market. Assuming one has access to 20 amp L1 (allowing 12 amp charging) most BEVs will charge at about 5 MPH which allows about 50 miles of range to be added per day assuming conservatively the car is home 10 hours per day. This is more than sufficient for many people to use a BEV with just L1 charging at least as an in-town car. And somewhat counterintuitively living with L1 charging only is _easier_ if one has a really big battery. For example, for my model 3 if I need to drive 30 miles per day for 5 days and then 120 miles one day on the weekend this is easy on L1 charging. Basically I have 200 miles of range after 5 days assuming I started “full”. Certainly L2 is more… Read more »
Strongly agree. I’ve been drivin’ on electrons since early 2013 and have never plugged in to anything except the L1 outlet in my garage and an L2 public charger exactly once for about 30 minutes, just to try it out. When I got my first EV, my wife and I looked into the cost to add L2 capability to our house, found out it would cost enough to fuel our car for almost two years of driving (not an exaggeration), and decided to try to live with L1. It worked for us, saving us a non-trivial hassle and expense. We’re now on our second EV (2018 Leaf), and we routinely drive between our house and a location about 65 miles away where I can charge at L1. Again, this works for us, and it took nothing more than the Nissan-provided EVSE and a wall socket at each location. I would also add that articles like this often talk about “future proofing” by putting in a 30 AMP outlet and EVSE. If that’s your plan, then PLEASE consult with an electrician before you dash off to some online retailer and start EVSE shopping. Adding a 30 AMP draw to many houses… Read more »

If your electrical panel can’t handle a Level 2 EVSE then chances are it needs replacement anyway. Putting in my ClipperCreek was the push I needed to finally do what I should have done 20 years ago which was to replace my 1960s panel with a modern one. The new panel is much safer than the old one and having a permanent LVSE is increadably convenient. You have a $50-$60K car, it makes no sense not to spend $1K on an EVSE, you paid more than that for the paint on your Model 3. I spent $40K for my Volt, before Fed and State rebates, so another 1K to buy and install a CC was nothing and likewise the $2800 I spent on the new 200A panel isn’t a lot when compared to the price of a Chevy let alone the price of a Tesla.

We did go for an L2 charger in our case because we have 2 BEVs and charging them on 1 20 amp L1 circuit wouldn’t cut it. Generally my wife uses the L2 charger for her Leaf while I L1 charge the model 3 and only borrow her L2 connection if I have been too lazy to plug into L1 for a few days. But, if we just had the model 3 L1 alone would be fine. As for the “plugging an L1 charger into a corroded outlet safety risk” some other repliers mention. Well duh. If I plug an L2 charger into a corroded 14-30 or 14:50 outlet there is even more risk. If the 120V outlet is in poor shape $5 in parts at Home Depot can fix that. Any sustained draw electrical equipment can be a hazard if plugged into insufficient infrastructure.

That is true – all things being equal L1 is safer since the current is lower.

I disagree, I think L1 EVSE represent a real safety concern. People use corroded outdoor outlets, poorly wired outlets, extension cords (without proper checking for damage or heat build up), etc.

As an example, I went to my mom’s place in the mountains, plugged in my Clarity PHEV using a 100 foot 12 gauge extension cord to an outdoor outlet that looked corroded. After an hour I checked the plug and it was hot of course, so I stopped charging, cleaned the outlet thoroughly, plugged it back in and it was cool (or just slightly warm) to the touch along the entire cord and outlet through the charging process. Using the extension cord is dangerous as there is no thermal sensor in the extension cord at the outlet or could be damaged internally. The corroded outlet was dangerous (and could have very likely melted out had I not checked it). The cord can get easily damage.

L2 EVSE (preferably hardwired) is much safer, plus much better experience. Don’t have people say: “Why isn’t my car charged, it has been an hour?”

PS I understand L1 will work for many people (up to maybe 40 miles per day driving), I disagree that it should be encouraged due to safety concerns and most general people won’t properly care for the L1 charger.

Maybe what should be done is a special 240 outlet be developed and installed in all new construction (1 per garage). Something with safety features like thermal monitoring built into outlet. This would probably cost less than all those annoying ARC fault breakers I am required to have…

Yeah just what we need – another dopey ‘standard’. Putting stuff in right and using proper equipment is and has always been the solution.

The only people having trouble with L1 are those DOPES who haven’t read their owner’s manuals. There all EV manuals state that car charging is a heavy continuous load, and it requires high-quality receptacles that have been tested to make sure they are safe by someone competent.

Since GM was having troubles with said DOPES regarding the 2011 VOLT, they quickly redesigned the current and all future units to have an AWG #14 connector cord, while keeping the AWG #16 connector cord to the car – why? – so that the oversized connector cord would extract heat from any overheating defective receptacle.

From instances I have seen in forums of melting outlets, they aren’t dopes. The bottom line is 120 V is terrible for power delivery and it is really unfortunate that US adopted that level. Often times it is the outlet failing even when used in specs, either from poor install, cheap outlet, etc.Also, they get damaged, it might have been fine when someone started using it, but they miss the damage.

The issue with using NEMA 5-15 receptacles is that people will use them stupidly. They will attach extension cords without knowing to properly check them for heat build up at the outlet and along their length. It just encourages bad use, modern EVSEs with heat sensors in the plug won’t work appropriately with an extension cord.

GM quickly realized this and changed the default to 8 A charging to prevent fires, and many others limit at 10 or 11 A.

That’s nonsense. No automaker sells a product that would be in anyway be dangerous.

You like many others here can wallow in their own baseless opinions, meanwhile millions including myself very safely charge up using 120 volts almost every night. I usually use a higher voltage for the BOLT, but the ELR mostly just charges on 120 the same as most VOLTS.

The basic concept of your point is looney. Voltage doesn’t cause heat, The only thing heat dependent for a given installation is the current – of which 120 volt charging is usually less than 240.

8 or 12 is usually less than level 2 installations. As I mention they are cool running and very safe. I dare anyone to find a 2012 Tesla MC charging at 40 amperes to say it is ‘cool running’. If it was very hot at the authorized Tesla Service Center, that is all I need to know.

Wrong again – The VOLT from the very first had a choice of 8 or 12 – it just wasn’t from the touch screen in the car in the first 2 years, it was a button on their ‘charger cord’. And there was no ‘default’. Unlike later cars such as my ELR and BOLT that must be constantly changed to 12 amps on L1 (yes, I know about zip code based charging on the bolt), my 2011 VOLT would stay at the setting you left it at since it was stored in the EVSE, NOT the car.

How about trying to say something accurate for a change? Almost everything you say lately is provably WRONG.

THE WORST connector I’ve seen has been the original Mobile Connector that came with the 2012 S. When I first saw it in Toronto, I said “You guys have got to be Kidding!”. Then I saw it in action in a Service Center, where it was badly overheating – at the Tesla SC of all places! They made 2 or 3 band-aid fixes to it, then finally, nowadays, you can’t even get the interchangeable plug version that was causing all the trouble on the 40 ampere model. For $520 you get a MOLDED Nema 14-50 with no connection points and therefore no ability to charge at 110 volts. You can see this whole thing is on its way out – good thing since the ‘evse car’ can have its circuit traces lift, and the 30 ampere rated relay in it doesn’t last forever on 40 amperes continuous. Of course, nowadays, all Tesla ‘occasional use cords’ come with an interchangeable cord that is AWAY FROM THE HOME WIRING, and is much reduced loading wise to 32 amperes, – even on the most expensive “X”. Most everyone there is encouraged to purchase the very good value High Power Wall Connector anyway –… Read more »

I think we are past the early adopter phase. The general public will not want to use only 40 miles a day. We have charged our volt and ELR at 110, but I did add a 50 amp plug to our new house. I just purchased a JuiceBox EVSE. So I get faster charging now and I’m set for our next vehicle too.

Many people do not own their own home and must deal with a landlord, who may feel that providing a high-quality 110 volt receptacle for the car to recharge is the end of their responsibility.

Since most VOLT owners charge at home using L1, It is premature to ignore it.

I don’t disagree with you, but I think someone renting and is considering an electric car will understand and accept charging limits before their purchase. In my opinion those are early adopters. My son wants a model 3. He test drove one and could probably afford it, but he’s waiting until he can charge it. I see plenty of apartments around me are installing EVSEs now. I would imagine market forces will get more landlords to install them in the future.

Teslas are a special exception since the S, X and Roadster all took a 30% hit to efficiency when charging at 110 and really needed 190-240 to charge efficiently. Other brands like GM or Ford or Toyota seem to charge relatively efficiently at 110.

I can’t speak for the Model 3 since I don’t know anyone who owns one yet, and Tesla has removed charging rates at 110 volts from their distance calculator.

Sorry.. gotta disagree here. I’m sure L1 charging can work for some people who don’t drive very much. But people who buy an EV thinking they are going to be able to do everything using the 120V EVSE are going to wind up ver dissatisfied with their EV owning experience. When you get buy a 240V unit from clipper creek for $300 these days, plus maybe a few hundred for electrical work, there is really no excuse not to get this done in most cases.

“FEW HUNDRED'(???? !!!!) – I remember when I bought my ELR, Cadillac would allow $3000 for purchase and installation of a $500-$999 EVSE along with installation. In those difficult installation cases, the owner would have to fork over the difference.

Electrical installations in Northern States are much more insulated from the weather than those of you in warm climates, so the typical installations for car charging are almost never $300.

My last NEMA 14-50 install with a 25 foot run was exactly $300.

Yes, unfortunately, in my house the car isn’t in the basement. I work cheaper than most electricians, but nowadays they hardly do anything for $300. My Neighbor across the street paid for a 1/3 hp 110 volt outlet for his pool mandated by the town to be installed by a licensed electrician in this town, and it cost him $1400 for a simple direct buried UF 14-2 cable and a faceless ground fault on a dedicated 15 ampere circuit. That was more than the pool and filter. It would have been $1500 but he saved $100 by digging the trench himself..

L2 is absolutely useful in cold climate, specially when you don’t have a heated garage.
Because a very minimalistic L1 level won’t be able to charge much while also having to keep the battery at a functional temperature, more less to preheat the car or the battery at optimal temperature.

Beside the Canadian electrical code require fully dedicated 20 amps circuit for 120 volts vehicule charging.
Common receptacle are week and cheap and are worn by abuse plugins and pulling all sorts of appliances in and out.

So you have to put new wire to have proper L1 anyway, you might as well put one that will serve properly 7times faster.

Great reasons to add L2 to your own garage, carport, parking spot: preconditioning vehicle will not reduce your SOC, lower fire risk than overloading an existing 120V circuit, more efficient charging, added resale value to your house, NEMA 14-50 outlet can be used for other things (welder, RV, heater, etc.), two EVs in the same garage, maximize off-peak charging, cool factor, etc.

When potential EV adopters ask me how long it takes to charge my i3 I don’t have to say “ugh… like 22 hours for a full charge…” Instead I get a much different reaction by saying: “after a normal day of use I plug in my cell phone and my car at the same time and usually the car gets to 100% first… but DC fast charging stations can go substantially faster”

With a smart charger the EV can be recharged at night and unless you are using electric strip heaters, even a 100 amp service panel can suffice. From 10 pm to 6 am there is no significant electrical demand (only the fridge or the furnace motor) to compete with the 32 amps for the EV. A drawback to L1 charging is having to leave the car plugged in for 3 times as long and having a power cord to trip over in the garage.

You really should drop the 110/240 volts statements and use 120/240 volts for residential installs. I don’t think 110 volts has been used since Thomas Edison.

110/220 is the load rating and 120/240 is what the circuit provides. The voltage could sag as low as 110 or 220 in use.

“I don’t think” – hehehe I’ll agree with that. My utility company provides 3rd world electricity in August. Most days the juice drops to 103 without anything on in the house. I’d love to have as much as 110. Fortunately, the L1 car charger works down to 100, and the L2 stuff works at 187 – the lowest I’ve measured. 5 big reasons why the juice is so bad, but then I’m not paying for the loss, so its not a biggie with me. Just worry a bit about the refrig and freezer.

Evil picture, don’t coil your cord tightly around the EVSE, it should hang loosely to dissipate heat 😉

If he ever turns his car on its side so that the car jack is pointed toward ceiling and plugged into the evse as shown, then I’d worry about it.

The thing about the picture that worries me is the receptacles seem to be mounted below 18 inches from the floor. That is a BIG NO-NO. IF there are any gasoline cans in the garage for an old lawn-mower, etc then he has just created an explosion hazard.

I have plenty of stuff in my garage, including plenty of filled gas cans, but I have nothing within 18″ of the floor. Even the hot-tub boiler is elevated, which is why you see gas water heaters in garages elevated by concrete blocks.

I’m not going to argue with your statement, it just seems funny to me that someone would tens of thousands on an Electric Car but still be using a Gas lawnmower!:)

I don’t. I’m on my second ELECTRIC lawnmower, which by the time I bought a decent one cost me around $1600 for the two. I gave the first TORO away since it only had 1/3 hp on a good day. The current Snapper I have puts out a bit more than 1 hp and it is the first batter electric I’ve tried that had adequate power. Unfortunately, I need $600 of batteries to cut my lawn, but the fast charger can keep up with my lawn cutting so I can do my HUGE lawn and also a neighbors.

My 2 stage 23 x 24″ CASE snowblower I home-made converted to a 3 hp extension cord electric (240 on the Tesla outlet – peaks at 35 amperes and 7 1/2 hp). I was worried that I had underpowered it but last March when all the gas blowers on the street were stalling on heavy water laden snow, mine just kept barreling down the sidewalk.

The Battery operated Snow Blowers you see advertised are just toys… Just figure out how big the battery is and the trivial amount of work it could do.

Need the gas for the generator, or the ELR during emergencies. Usually just use the bolt and elr for home juice during power failures. I answer the lawnmower comment after they approve the moderation.

Viking if your cord is getting hot, it’s being overloaded. Time to upgrade the circuit wiring and breaker. The cable doesn’t necessarily have to feel cold, but it shouldn’t feel noticeably warm to the touch either.

The owners manual for the Clipper Creek unit shown in the picture specifically says not to wrap the cord tightly like shown in the picture. If you do the cord WILL get hot internally even when properly wired during a long charge. It needs that open space to vent heat. The cord will stay cool if coiled properly. Whenever people not knowing otherwise coil the public chargers like that I will loosen them up.

Love and recommend the Clipper Creek HCS-40P for BoltEV owners. Solid. Easy install. Neat.

I guess writer JIM must be a “NEWBIE” or is otherwise mis-informed, but IEVs is continuing the FICTION that Underwriter’s Laboratories (UL) ‘CERTIFIES’ anything. He isn’t alone since every IEV writer says the same thing and its getting to be an echo chamber – but the end result is that IEVs is passing out bad information.

In their best days (unfortunately behind them), they have merely LISTED an appliance. (Listing is currently their TOUGHEST CRITERION).

In plain English, what that means is that the thing AIN’T CERTIFIED FOR ANYTHING. It just means the device has met MINIMAL safety concerns, when operated under typical conditions. It doesn’t say anything about out-of-the-ordinary conditions.

Level-2 isn’t required for charging at home, but it sure makes life a lot easier. I wouldn’t use or recommend using a standard outlet for Level-1 charging unless it’s a dedicated circuit with it’s own breaker. With the larger battery packs these days Level-2 charging is becoming more popular if not necessary. Consult your electrician, but I personally think pulling wiring that will handle less than 50 amps is a waste of time. You can use a smaller circuit breaker, but the wiring needs to be robust. Most modern homes built in the last 10 years or so should have a 200 amp panel anyway, so you aren’t going to notice an EV plugged in. Again, consult a qualified, licensed electrician. Also, before you let your ‘handy’ brother-in-law install your charging station, be aware if there is a fire from improper installation, your home owner’s insurance will most likely NOT pay for the event.

Not to be argumentative, but please show me a case in which a H/O policy denied coverage for a fire loss because the homeowner used a non-UL listed device. H/O policies are contracts, strictly regulated by each state’s insurance department. The vast majority of H/O policies are “All Risk” based, meaning that you are covered for everything unless there is a specific exclusion for it. I have read many times on this forum and others about H/O policies not covering such claims, please show me ONE that actually is true. There may be one out there, but I have never seen it.

We need to post a DIY article for adding a L2 charger. It’s so easy to do in an afternoon if you have the electrical panel in or close to the garage already (many/most do) and parts cost about $50 to do a basic install on a NEMA 14-50 outlet. In most places it is legal to do your own electrical work in an owner-occupied single family home. Permit + inspection by the AHJ is probably ~$100 or so which is worth it when it comes time to sell the house or if ever there is an insurance claim necessary. If you are going to do it, do it right. Don’t trust that somebody else (an electrician) will make all the right decisions for you. Minimum for today (my opinion) is a NEMA 14-50 outlet on a 50 amp breaker with 6 gauge 3 wire NM-B. This will give you a 40 amp continuous capacity for EVSE which is likely a model year or two at most in the future for standard onboard EV chargers. If you have to trench or go through any major headache to get to the panel, go to a real electrical supply house and get… Read more »
Nonsense. #8 copper wire if it is Romex can be used on a 40 ampere circuit so it is good for a 32 ampere car and EVSE. HPWC can be set up for anything from 24 to 80 amperes so it depends on what the owner wants, or, in a Commercial installation – say a ‘destination charger’ how much they want to push up their demand fine. Anything other than Romex (NM) or direct burial cable (UF), the #8 can be run at a 75 degree Centigrade rating (if copper), and thereby it is good for 50 amperes – so 40 amp charging of a Tesla is fine. Most of the home Tesla dual charger installations you read about – the electrician has run a 100 ampere ckt on #4 copper due to the residential exception, which passes inspection even though it probably should not. Put it this way: I haven’t seen a 24 ampere evse run on anything larger than #10 ever, or a 30 amp Chargepoint run on anything more than a #8 ever (other than my own home – where obviously going bigger isn’t a problem) – even when the resulting charging voltage at extreme distances is… Read more »

Haha the big experts get all positive votes, but yours truly with a Master Electrician’s License gets all negatives. Hey, Believe what you want.

My situation is a good example. I just purchased a new house and unfortunately it does not have a garage. Until I get the garage built in the Spring with a NEMA 14-50 outlet, I’m going to rough it with L1 at 120V/15A.

It’s been a week and I am almost constantly having to keep the car charging while at home just to keep up. On my previous L2, I charged every 2 to 3 days. My first problem was the outlet closest to the driveway shares the circuit with the family room. Oops, popping the breaker every time. The front of the house outlet wasn’t any better. Luckily there is a basement outlet I can drive to and get a charge with no issues.

You now have a Tesla 3 correct? What is the efficiency hit by using 120 volts? It used to be a 30% hit for the S,X, Roadster, and new Rav4Ev with the Tesla drivetrain, Meanwhile 12 amps at 115 for a VOLT is quite efficient.

I can’t speak for the ‘3’, but you can – since you can at least compare your cost of charging with the 240 – 250 volt cost in the Tesla Calculator.

The Model 3 is showing 118V @ 12A which is 1.4kW. The same screen shows 1kW/hour being added, but it is rounding down. I need to take a 8 or 10 hour session and total up the numbers.

I’m certainly pleased the US Air Force along with the wind turbine industry taught me just a few skill sets in getting that Level 2 service expeditiously installed.

Didn’t have to purchase any EVSE. My 2016 Volt came with one, that was L2 capable. You only needed to make a pigtail. It’s actually a Clipper Creek. So, for about $60, I installed a NEMA L6-20 outlet, with 20amp double-pole breaker, and 8 ft of 10-4 wire that I had left over. $20 got me a permit.

My Tesla Model 3 came a week ago, Thursday, and I traded in my Volt. So, I swapped out the NEMA L6-20, for an Eaton box with NEMA 14-50 receptacle, 8ft of 6-4 wire, and a 50 amp double-pole breaker. About $75 at Lowes. Yes, the Tesla came with a L2 EVSE that charges at 32 amps. You could buy the Tesla HPWC for $350, I think, but it’s totally not necessary for most.

I’ve paid 18’000.- CHF in Switzerland back in 2017 for a 9.3kW roof top installation and I’ve gotten 5’580.- CHF back from the Swiss government in cash. That’s like 13 cents per watt installed 😀
But I’ve had offers going as high as 32’000.- CHF for the same. So you need some luck and you have to behave like on a bazaar or else they rip you off! Go for it! We all (even my wife 😛 ) enjoy our solar power and I am saving for an EV!!