Solution to avoid range anxiety - Carry a generator

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Here is a demo of someone doing this on his Tesla Model S. It certainly would be nice to have the flexibility to set the power level of the generator's output from the car's center console. On the other hand, the RAV4 is quite possible the ONLY EV currently available with enough room in the cargo area to easily haul one of these things around in the car itself.

https://www.youtube.com/watch?v=_psP-XrGO9U
 
Coming into this abit late.. but when we go out to the desert to test and fly our "stuff".. I've been taking the Rav more and more, so the solution was pretty clear. I was already carrying a 2000i for charging my flight LiPo's... and it's about 85miles 1 way to the dry lake.. and we stay the whole weekend..

So I just put on the new hitch (thanks Tony, Philip, etc for the thread and pics) and I already had a cargo mount.. The 3000i works great with a OpenEVSE. Customized the FW to have tons of selectable ampacity on L1 from 6 to 24a (for a MS)..

Works great.. and I made a gen-box so it's dead quiet.. lift it off, move it 20ft away, and it you don't hear NOTHING. It'll charge the Rav, and anything else I need for the weekend..

195fa6e8a71f4dab9962d6aeeafcb17a.jpg


Added an ext runtime tank as well... built it into the box..
 
Does your Honda generator only permit charging at Level 1 amperages? What is its continuous output rating? Most of the gens up to 3000W ratings only have 120V outlets built-in, so you can only do L1 charging. Of course, I guess that's fine if you have all weekend to recharge. But, if your going to drive the RAV4 around during the day, I would want it to be fully recharged while sleeping each night. The minimum gen capacity I would consider would be 3500W continuous and most have 240V outlets (L14-30R).

At this power level, you can charge using a L2 EVSE at 240V, or at a battery energy replenishment rate of about 3kWh allowing for charger eff. In 10 hours, an RAV4 EV would be almost back to a full "normal" charge with a range of about 90 miles (assuming a driving efficiency of at least 3 miles per kWh). Of course, the generator's gas tank (assuming a capacity of 4 gals) would need to be refilled about once every 4 hours, so carrying a 5 gal gas container with you and filling up just before you reach your destination might be necessary if gas station are few and far between.

The only tradeoffs with a generator capable of supporting L2 EVSE charging are the added noise and weight, but using to recharge each night, if necessary, should keep out of town trip range anxiety to a minimum.
 
No, none of the inverter style gens will have 240v output unless you really start getting into the 5-6kw output or higher. Yamaha or Honda.. cheap knockoffs that are junk squarewave or modified output that just use a generator head can do 240 on a 3000w unit but those things are..

1.Junk
2. Loud
3.burn through TONS of gas
4. cannot run anything electronic really on them.. Try any apple product and see :lol:

My 3000i in eco mode will charge the Rav in 14-18 hrs no problem with how I have it dialed in.. depending on state of charge, and ampacity I set the EVSE at. It'll put out 2600w continuous or 3000 for 30min...

But I'm a firm believer in running things for the long haul at less load, then FULL BOAR and burn it out.. Remember, ANY INVERTER gen set has a both coil packs and a transistor pack (module) and you see people ALL THE TIME on the RV forums burning them out because they run them at or near full load 100% of the time..

Doesn't matter if it's a Honda, Yamaha(great units!), Onan, etc,etc..

But this unit purrrs putting out 1600-2000w all day.. all night.

EDIT.. and to answer.. yes. It's a L5-30 plug.. L1 charging and it takes me 4-7gal of fuel to power my ENTIRE weekend of fun.. charge the Rav, my flight packs, etc.. not to shabby..
 
I share your concern about a generator's output sine wave distortion, but I think the EVSEs, by and large, will not be that sensitive to those "other kind" of generators. Most EVSEs have their own internal power supply for the "electronics" control circuits, so unless the AC input is really bad (>10% THD), I don't think there will be any issues. For charging a cell phone or laptop, or watching a portable TV, I would use the DC cigarette outlet(s), or the USB port in the RAV4, with a DC to AC inverter module if necessary, so no problems there.

There can be no debate about the added weight and noise as being the real issues with these "other types" of generators. They weigh at least 130 pounds even without any gas in the tank. And the noise they make is generally over 72dB. In a "public" place that much noise can be a really disturbing annoyance. However, you have to stay within ear-shot of the generator to hear it running in case it suddenly shuts off (potential theft situation) or it runs out of gas. However, its use is only for "emergencies", so you might not even need it on a trip if there are public L2 EVSEs along the route or at your destination. It's nice to have along in the back of a RAV4 EV just in case your stuck somewhere out in the middle of nowhere. :mrgreen:
 
You're pretty much wrong on all accounts.. especially the sinewave/squarewave and modified wave outputs.. if you plug a TV into an standard gen.. good luck with that.. and you'll see noise...

As for weight, the Honda 3000i weighs 71lbs..and is 59-65db's.. with my box.. you cannot hear it.. There's a reason why companies started to make these "inverter" generators..

And yes, there have been reports of sensitive things burning out on standard gen sets.. they are good for refrigerators, etc.. I would not plug one into my EV.

And also, Chris's OPENevse uses a very nice switching PS.. on the v2 units.. I would not run crap power on that either.. :roll:

IMG_7674_1024x1024.jpg


Notice the 50/60 hz :lol: try getting that on a square/modified wave unit... good luck
 
@dsinned, The EVSE may not care, but if you read the Tesla Motors Club forum, you will find that Tesla on-board chargers do care about the power quality and will error out when they don't see "grid quality" power. The RAV and the Model S may be slightly more tolerant than the Roadster, but the universal conclusion is that if you NEED to use a generator, you need inverter output.
 
miimura said:
@dsinned, The EVSE may not care, but if you read the Tesla Motors Club forum, you will find that Tesla on-board chargers do care about the power quality and will error out when they don't see "grid quality" power. The RAV and the Model S may be slightly more tolerant than the Roadster, but the universal conclusion is that if you NEED to use a generator, you need inverter output.
Miimura, I concur. Precision voltage regulation on less expensive generators (i.e. those made in China) is typically lacking. Hence, unless the EV's onboard charger is VERY tolerant to voltage droop at turn-on (almost equivalent to a low voltage brown-out-like transient), they may not work very well with one of these non-inverter generators. The higher the HP rating of a genset's (gas or diesel) engine, the less likely this may be a problem. But then, you have to contend with a premium price, more weigh and noise at higher load.

I believe Honda makes a series of generators with more responsive voltage regulation control. This feature in Honda's literature is known as "DAVR" (Digital Automatic Voltage Regulation). Unfortunately, those gensets start around $1500 at only 3500W rated output power. Honda's inverter gensets are quite expensive, tend to be lower power rated, and most do not even support a 240V load application.

I'm going to try an experiment over the FOJW (4th of July Weekend) with a Chinese made, 3500W (continuous load) generator. The model is a DuroStar DS4400CA (CARB legal). I'll use my VOLT as the guinea pig in this experiment, with my Leviton "L2" EVSE plugged into the generator, and see what happens. I know it will work using the Voltec (OEM) 120V charging cord as the load current will not exceed 12amps (1440W); not even half the generator's output rating. Also, I already tested my RAV4's Sumitomo (OEM) 120V charging cord plugged into the same generator and that worked fine as well, although it was less tolerant of the AC output fluctuations, and required Earth grounding the generator to even work at all.

Stay tuned . . .

***UPDATE***
I got really curious, so I took off a little early from work today, stopped at RS for a 25' length of Earth grounding copper cladded steel bare wire, got home a few hours before sunset and just completed the above "experiment". Surprise, SURPRISE, it actually WORKED!!! I was able to sustain a full load (~3300W, 232Vac at 13A, measured at my Leviton L2 EVSE's output) on this "El Cheapo" generator for about 15 minutes before it ran out of gas. I only had a couple tenths of a gallon, because I forgot to stop at the gas station and fill up a portable 5 gallon container with unleaded, 87 octane Chevron gas. I'm still breaking in the generator's, 4 stroke, single cylinder, 210cc engine, so it was just as well.

The only thing I can think of that seems important is to properly Earth ground the generator, or there would be a good chance the EV (in this case, my 2012 Chevy VOLT) will not accept the charge.via ANY L1 or L2 EVSE.

Next on my "to do" list is get the JuiceBox and try the same thing on my 2012 RAV4 EV! Unfortunately, that could be a few weeks from now because my JB is on back order while waiting for a 25' (32A) J1772 cable to go with it. By the way, the JB has a "universal" AC to DC power supply, that operates over the range of 100 to 240Vac. I would think, such a wide operating input range, should almost GUARANTEE compatibility with my DuroStar portable generator.
 
It's really the car's charger that you need to worry about, not the EVSE. So it's a great sign that it works on the Volt, but since the Volt and Rav have completely different chargers you really need to try the Rav too.

As far as the grounding thing, hasn't it already been explained to you how you can "trick" the EVSE into thinking it's grounded by inserting a 120v plug with resistors into the generator? Of course it's preferable to have a real ground, as you did, but if you plan to be charging from a generator in unknown places you definitely should have one of these "resistor plugs" ready.

Lastly, the Leviton is a non-adjustable 32a EVSE, right? It may not be the best idea to have the car's charger trying to pull 32a (or 16a in the case of the Volt) from a generator that can only supply 13a. You may have gotten lucky that it ran out of gas before you blew a fuse... Maybe you should wait for that Juicebox after all and set its pilot to 12a or less before trying again. Or perhaps that's what you were already thinking, as maybe the generator is rated to handle the full 16a the Volt can take (why was it pulling 13a then, I wonder?)
 
The Volt's onboard charger has a "3300W" maximum charging capability at 240V, so that is why it only draws 13A; a perfect test of my 3500W generator, which has 13.5A circuit breakers (on the 240V outlet's) overload protection. The "trip rating" is actually 14.8A. The AC line voltage was actually ~230V (measured at the EVSE), so the generator was putting out ~3000W to charge my Volt. This, I think, is an adequate "derating" of a 3500W continuous output generator when the OAT is reasonably warm.

I'm still breaking in the generator, so I only ran it under load for about 10 minutes. I notice that the load current was slowly rising as the charging circuitry warmed up. I think the current would have creeped upward to about 14.5A if I had continued charging much longer. That would put a load of about 95% of the generator's rated output (3500W). With a JuiceBox charge, I will probably limit the current to 14A (at 240V), so the generator does not overheat, especial if the OAT is over 70F.

Fooljoe, you're right, I will NOT be using this generator with my Leviton L2 (240V/32A) EVSE to test on the RAV4! A 7700W, 240V/32A L2 EVSE (i.e. my Leviton unit) is way too much load on a 3500W generator!

Btw, I did try charging my RAV4 with the same generator using its OEM (Sumitomo) 120V charge cord that came with the car. With an Earth ground to the generator, that worked fine, but not when I added the Volt's OEM (Voltec) charge cord and tried charging my Volt at the same time.

Both charge cords are stock L1 EVSEs, and each current limits at ~12A, for a total combined load on the generator of ~2900W. Something odd was happening with the RAV4's onboard charger during this simultaneous charging operations. Every few minutes the generator bogged way down causing its output voltage to drop out of regulation low. Of course, this caused both car's to cease charging every time that happened. It was like the RAV4 was trying to step up the current from its EVSE for reasons unknown, thus putting too much load on the generator. This was like a "brownout" transient that interrupted both cars from continuing to charge normally and faulted the onboard chargers. I have no idea what was causing this to happen. Nevetheless, this was just a way to do a high load test on the generator at 120V; something I would not normally ever do again with TWO L1 EVSEs. Must have been some kind of weird feedback loop. Any other theories on what was happening?

While charging one car at time, at 120V, with each car's own L1 EVSE (up to 1440W), or my Volt with a Leviton L2 EVSE (up to 3300W), I had no problems with the generator! I suspect the JuiceBox hookup up the generator should work well as well on either car. With respect to the RAV4, I should be able to charge at 3300W; same as the Volt, because of the JB's fully adjustable current limiter. SWEET!!! :mrgreen:
 
Oh, I thought the Volt's 3.3kw charger was rated in terms of output power, just like the 1st generation Leaf. The Leaf's charger is also advertised as 3.3kw, but it definitely draws up to 16 amps.

That's interesting how the charging won't work with both at 120v, but very promising that the Rav can charge at 120v from the generator. It seems pretty unlikely that if power conditioning were the potential problem that 120v would work but not 240v, since I'd think the shape of the wave should be the same - just the amplitude would be different.
 
fooljoe said:
Oh, I thought the Volt's 3.3kw charger was rated in terms of output power, just like the 1st generation Leaf. The Leaf's charger is also advertised as 3.3kw, but it definitely draws up to 16 amps.

That's interesting how the charging won't work with both at 120v, but very promising that the Rav can charge at 120v from the generator. It seems pretty unlikely that if power conditioning were the potential problem that 120v would work but not 240v, since I'd think the shape of the wave should be the same - just the amplitude would be different.


A 2011-12 LEAF has a 3.3kw charger and a 3.8kw load. A 2013-14 model has a 6kw charger (not 6.6) and a 6.6kw load.
 
A DuroStar DS4400 is ideal to charge a VOLT at full power (3.3kW), however I only plan to use it for an "emergency" charge with my RAV4 EV. It fits perfectly in the sunken cargo hold and can be tied down with steel eyelets that are anchored to the car on either side of the rear door. It weighs right around 100lbs (dry), so I can manage to lift it in and out of the car by myself (albeit, with great effort). My primary charging method while on the road will be at in-route RV Parks using my portable Juicebox EVSE. With the availability of 50A outlets (NEMA 14-50R), commonly available at RV Parks, I will be able to recharge at 10kW, to gain about 30 miles in range per hour. Without any public charging stations or 240V outlets available, and I'm just about out of range, the DuroStar will ALWAYS be there in a pinch for an emergency charge. However, the fastest emergency recharge rate will be only add about 10 miles per hour, which is still minimally acceptable for an overnight stop. I'm still waiting for a JB to test with the generator, but I have nearly 100% confidence that it will work.

Therefore, I believe this about the lowest cost solution (~$1000 for genset + JB) in avoiding range anxiety where ever I might go (Yosemite?) in a RAV4 EV! :mrgreen:
 
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