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Will’s video & the holy grail of EV/hybrid vehicles as simple backup generators

PriusFan

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It’s amazing to me that Will posted this video nearly two years ago and the portable power industry seems not to have responded.

As far as I know every EV/hybrid vehicle with a traditional 12v battery, in addition to a traction battery, can attach an inverter and pull at least 1000 watts continuously (as least 1000 watts is the accepted wisdom for the Prius - I own a Prius). As Will illustrates when the vehicle is left turned “on” the traction battery will provide the necessary charge to maintain the charge under load of the 12v battery. Problems only develop if you run out of traction charge on a EV or gas on a hybrid.

Will explains that if you are off grid and have a series of miserable solar days you can use your EV/hybrid to recharge your battery bank.

The portable power station manufacturers have successfully made solar charging central. That’s as it should be. They often also ship cigarette lighter chargers which charge at the 150ish watt limits of that port. It seems no one is selling a portable power station charging cable that connects directly to the 12v car battery like Will does here. As Will illustrates using the 12v battery directly will charge a power station much more quickly than the cigarette lighter.

These portable power stations already often have significant solar DC input rates. And at least one portable power station permits solar charging of a maximum of 800 watts and has a 12.5 volt minimum input requirement at the bottom of it’s solar input range. The MPPT is built in. (It charges from the wall at 1200 watts.)

I may be missing something very important but given the 12.5+ volts we generally see Will report in the video could a portable power station like this simply be connected to the EV/hybrid 12v directly? Eliminating the losses of the DC to AC inverter or the DC to DC converter Will references in the video? If your goal is immediate AC power one uses an inverter as Will does here. But if your goal is to charge a 12v DC system it would be ideal to do it directly without these DC to AC to DC or DC to DC series of conversions. (I’ll note here that very few portable power stations are 12v systems - most are 24v or 48v and their voltage input ranges fall above 12 volts. To accomplish what I am describing here would require a voltage booster to be built into the cables to these systems such as Will references. And manufacturer liability may be a big reason this option seems not to be offered.)

However I would think that when manufacturers create portable power stations that can easily be connected directly through one cable to EV/hybrid 12v batteries for high speed charging of DC systems they will have a hot product on their hands. Particularly if it can simultaneously discharge nearly the DC input wattage as AC through the built in inverter (instead of, as Will does, effectively having an AC inverter charging another AC inverter in the portable power station).

Ideally we avoid fossil fuels altogether but if an EV/hybrid backup makes people more secure about investing in solar, or more likely to buy an EV/hybrid then that seems to be a win for the environment.

But time for your advice. After watching Will’s video can a very heavy duty direct cable be created as easily as I suggest? **If the portable power station input voltage is in range of the vehicle output can one create a heavy duty cable that skips the intervening inverter/converter technology and connect the 12v battery directly tp the DC solar input on the battery bank or portable power station with the MPPT managing the charging?**

Thanks in advance for any thoughts.

Update 1: It is true that upcoming EV/hybrid vehicles will likely have AC inverters and outlets built into the vehicle. Sometimes accessing the traction battery for tremendous power. Toyota is installing 1,500 inverters at high trim levels.

But there are a ton of EV/hybrid vehicles already on the road. I’m particularly interested in the technical side and avoiding the inverters and converters with a direct cable for charging. Rather than repeat my key question I’ve added “**” around it above. I’ve also made some additional edits.

Again the goal is straight DC wiring and much faster charge than a cigarette lighter. I’m realizing this will require very robust cables to carry charge at a sufficient amperage.
 
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In other countries its been a long norm for EV's to back up the grid..

You'd have to ask our political class why they prefer kickbacks over effective legislation when companies/Government agencies Can't/won't make common sense things happen themselves...
 
This is why I'm excited for the cybertruck. ~200kwh of energy to add to my system during outages. That'll last me days. Once it gets close to empty I could just drive to a super charger and charge to full very fast.
 
Depending on the system outage, the supercharger might be off-line as well.
This actually happened to me this year during a big storm. The two closest superchargers were offline so I just went to the third closest. Actually it was the 4th closest but the 3rd closest was only a 72kW charger so it made sense to drive a bit farther to the 250kW charger.
 
Reminding myself that often Will has already pretty much answered your initial question:
 
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