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▲ amluto a day ago

A manual switch doesn’t solve the problem: there still needs to be a way to inform the inverter that the switch is open.

▲DenisM a day ago | parent [-]

It solves my problem just fine - power critical loads for a few days by spending $100 upfront fir the cable and 5 minutes to manually switch the load. It’s a difference between moving to a hotel for indefinite time and staying put.

Sure you can set a loftier goal and spend tens of thousands of dollars and countless hours solving it. Most people won’t though.

▲amluto a day ago | parent [-]

Sorry, what device are you using to supply power once you've flipped the switch? Sure, you can get a (legal, even) manual transfer switch and plug in a little portable generator, but if we're talking about using your car as a power source, this is not going to work.

▲DenisM a day ago | parent [-]

I previously used a portable propane generator for a 30amp inlet to transfer switch. In my test runs it didn’t go that high.

Today I could plug in a car that gives off 20amp into the same inlet, it would limit how much load it can carry, but I could stay below 2.4 kw if needed. Why wouldn’t that work?

▲amluto a day ago | parent [-]

A lot of houses won’t run off 120V/20A. You’ll also need to kludge around the fact that your house wants 120V/240V.

In any case, serious V2H should support much more than 2kW. An EV with a charger with less than 6kW capacity is almost unheard of. Two EVs should be able to supply twice the current. All that’s technically needed is an charger that is physically capable of operating as an inverter (which I believe adds little cost), some way to derive a neutral (the usual solution is a relay and an autotransformer, again not particularly expensive), and the control logic to convince all of the above to actually operate in this mode.

▲leetnewb 14 hours ago | parent [-]

What about using a step up transformer to send 240V to your panel from the 120V output from some EVs?

▲amluto 8 hours ago | parent [-]

This whole approach has an excellent chance of working extremely poorly. A device intended to power a whole house will have the ability to supply someone’s idea of the inrush current needed by a house, the reactive and harmonic current needed by a house, and the quality of waveform needed by a house. An EV’s 120V socket may be designed to operate one appliance for a while, but a single appliance may be a very different sort of load than hundreds of watts of crappy LED.

Also, this whole idea of connecting an EV via a manual transfer switch involves running an entirely separate cable connected to an entirely separate point near your main panel. The cost-effective (but currently mostly impractical solution) is to use the same physical wires for charging and for islanded V2H.

▲leetnewb 8 hours ago | parent [-]

I don't disagree, but assuming V2H is vaporware...10kWh home battery with ATS and capacity to saturate the house surge and noise, solar panels to run house / recharge battery, EV 120V to steadily feed the house battery to supplement solar.