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What are some cool benefits of driving electric?

• Instant. Torque.
• No oil changes
• Silent idling
• No toxic exhaust: great for your health, your kids’ health, cyclists, city smog levels, and you don’t have to worry about suffocating in your sleep from carbon monoxide (Remember, there is no safe level of air-pollution exposure.)
• Stop and go traffic actually means higher efficiency
• A transmission that doesn’t need to shift
• Regenerative braking: good luck refilling your tank in a gas car just by slowing down
• Never having to stop for—or even handle—gasoline again
• So much footroom, even for the middle back seat
• Live in the future, today

How does the $7,500 federal tax rebate work?

Basically, if you buy a new electric car with more than 17 kWh of battery capacity, you’ll be able to reduce your federal income tax burden for the year by $7,500—except with Tesla, which is $3,750. That's because Tesla has already sold so many cars that the phaseout has begun for them. The phaseout is calendar based and begins after each manufacturer has sold a total of more than 200,000 EVs. Learn more at the IRS site.

What really affects my car’s energy consumption?

For the most part,

1. distance driven
2. average speed (slower uses less power than highway speeds)
3. elevation gained

Pretty much in that order. Other factors for EVs are: use of cabin heating, ambient temperature outside (warmer = better efficiency), suboptimal use of regenerative braking, winter tires, etc.

How far can I expect to go on a full charge?

The official EPA estimates in the US are actually pretty realistic for mixed driving. For highway driving, you may get a little worse range (as aerodynamic drag increases superlinearly with speed). For low speed stop and go driving, you may get dramatically better range ('idling' uses practically no power).

What’s all this L1, L2, L3 charging nomenclature? How long does it take to charge and why?

There are two basic sources for battery charging: AC power or DC power. TL;DR: standard wall outlets take longer to charge your car, and DC fast charging stations can charge your battery in minutes.

In the US, a “regular” wall outlet at home supplies 120V of AC; dryer outlets provide 240V of AC. In both cases, your car’s battery actually needs DC to charge, so the power must be converted by an inverter that’s built into your car. After voltage, the second part of the equation is current (measured as “amperage”), which is limited by how beefy the wires and circuit breaker connecting it are (you can tell by the outlet style). Voltage multiplied by amperage tells you how many watts of power (e.g. 240V*30A=7.2kW) you can get to your car’s inverter—and thus defines the speed of battery charging. The car’s inverter also has a maximum amperage, but most people don’t run into that limit currently.

As described above, this is the most common means of charging: L1/L2 at home using an “EVSE” (a fancy name for what is basically an extension cord specifically designed for electric cars). EVSEs connect to home power on one end and the car on the other with a "J1772" or a Tesla type connector. They also add safety and some provide features like metering and remote monitoring.

If you want to charge a battery much faster, for many electric cars it’s possible to skip the on-board AC-DC inverter and provide the car directly with DC power (i.e. by using a giant inverter outside of the car). This is referred to as “Fast DC charging” (L3), and it uses a special connector. There are a few varieties: the Tesla connector (Tesla Supercharger), “SAE Combo” (J1772 plus extra pins), and “CHAdeMO” (enormous round one). Fast DC charging is particularly well suited for road trips, enabling you to substantially charge your car in minutes. 50 kW is a common max power for generic Fast DC chargers; 120 kW is common for most Tesla Superchargers (though newer urban ones only reach 72 kW).

In all cases, actual rate of charging is limited by the most constrained part of the chain, and that might be as simple as your car’s “battery management system” deciding to slow charging as the battery’s state of charge approaches 100%. You typically will get full-rate charging at least up to 80%, but it varies and can depend on temperature.

Technically, regenerative braking provides AC as well (generated by converting inertia to slow the car), but that’s just a neat fact.

I love outlets. Tell me all about them.

For AC charging, NEMA 14-50 is the best option all-around. It provides up to 10 kW, is found at many campsites/RV parks, and has been widely adopted by the cars with the biggest inverters (Tesla). If you’re going to install something, don’t bother with other outlets.

But. There are other outlets. The most common one in American homes is of course the NEMA 5-15, which can provide a maximum of only 1.5kW. Sometimes you may also find a NEMA 5-20 outlet, which has the T-shaped opening for one side and can provide 2kW. Dryer outlets also vary tremendously, mostly by how long ago they were installed, but can be a decent way to get a high power circuit without installing a new outlet.

Also, random EVSE manufacturers like to use uncommon outlets for no good reason. ChargePoint likes 6-20 and 6-50. For most of these oddball plugs, there's not much value in choosing those over just having it hardwired with no outlet involved. To recap, the chain looks like: AC from your power provider -> outlet or hardwire -> “evse” -> inverter in car -> battery

Note: for plug in (not hardwired) EVSEs, always ensure it is fully inserted into an outlet that's in good condition.

Range recovery rules of thumb:

120V * 12A = 1.44 kW ~3.5 miles of range per hour (e.g. standard US plug)

240V * 30A = 7.2 kW ~22 miles of range per hour (e.g. many dryer outlets)

240V* 40A = 9.6 kW ~29 miles of range per hour (e.g. NEMA 14-50)

Tesla Supercharger ~170 miles of range in 30 minutes