MASTER THREAD: Powering house or other things with Model 3

[lemketron]

Sure, emergency use is totally different. I'd pay a lot per kwhr to keep my house running during a power outage.

Same here. I just want to keep my fridge going and maybe internet and some lights as well.

But for routine V2G, I think basing the cost on 1000 cycles makes some sense. You won't want to keep the battery in your car after it degrades to <80% of the original. Maybe you could sell it for a second use, and so it has some value, so those earlier cycles aren't as expensive as we think. Also, if replacement cost in X years is a lot less than $25k, then today's cycles aren't that expensive either.

But, in any case, given that uncertainty, I'm not giving power back to the grid unless they pay me a lot per kwhr.

The grid operators are paying a buck a kWh or more during peak times. Currently demand response reductions don’t enjoy the same compensation but hopefully we will get there. Imagine getting ten bucks an hour for an hour or two only when these emergencies happen as they did recently. 100K vehicles (and/or powerwalls) configured to do this would be like finding a new gigawatt power plant (or ESS). Current grid-scale ESS supplied closer to 3GW during the recent emergencies.

This is an interesting article describing the situation and pushing for better compensation on the demand reduction side. As an OhmConnect member, I can personally vouch for how frustrating it is to participate in a DR event and then get told I consumed more than my “baseline”.

Californians saved the grid again. They should be paid more for it

Smart thermostats, solar-charged batteries, EVs and other household devices can shore up the stressed grid. Why isn't the state going all in on incentives?

www.canarymedia.com

 

[Richard234!]

The Tesla battery is expensive and not designed for such usages. Neither is the included 12v battery. You are not only ruining your battery but you will be stealing from Tesla if you later submit a warranty claim for battery degradation. They offer a long 8 year warranty.

"Vehicle to grid" is not economical right now because they are not designed for such heavy cycles (maybe because of being packed so tightly) and are not cheap enough to ruin.

Be that as it may, --- for tesla but lets open our eyes to whats going on with the Ionic, the Leaf, Rivian and others who have already been offering same power to house as backup power source option for some time...Have they figured out something Tesla has not ? Sticking by the ole tesla warranty and fear of misuse of the battery schtick much less chiding those who feel they would like the feature, wears abit thin in light of what others are already doing, or so it would seem ...

 

[fiveangle]

I […] understand attaching a large inverter under the seat causes the safety to trip due to large current inrush.

My friend [SIC] connected their 1100W sine wave inverter with an Amass XT90 "anti-spark" connector which is designed for high-powered remote control vehicles with large brushless speed controllers with correspondingly large smoothing capacitors, so it includes a resistor tip that is designed to pre-charge capacitors a bit during connection in order to limit the inrush current and it seems to do the business for this purpose:

Amazon.com

 

[n2mb_racing]

My friend [SIC] connected their 1100W sine wave inverter with an Amass XT90 "anti-spark" connector which is designed for high-powered remote control vehicles with large brushless speed controllers with correspondingly large smoothing capacitors, so it includes a resistor tip that is designed to pre-charge capacitors a bit during connection in order to limit the inrush current and it seems to do the business for this purpose:

Amazon.com

That would work. Though, if the car goes to sleep with the inverter plugged in and then powers back on after the caps have discharged, it might trigger the fault.

 

[IvanFL]

Has anyone installed an inverter, above 500W?
I don't mean an inverter just capable of 500W, I mean an inverter correctly wired to provide at least 500W. I need it to power amateur radio equipment.

 

[cali8484]

Has anyone installed an inverter, above 500W?
I don't mean an inverter just capable of 500W, I mean an inverter correctly wired to provide at least 500W. I need it to power amateur radio equipment.

I've run a 2kW inverter off the DC-DC converter.

 

[kellogg76]

I've run a 2kW inverter off the DC-DC converter.

Can you recommend an inverter that's plug and play? Ideally I don't want to have to add on relays and resistors to slow the inverter from pulling too much power at the start.

 

[cali8484]

Can you recommend an inverter that's plug and play? Ideally I don't want to have to add on relays and resistors to slow the inverter from pulling too much power at the start.

I'm not aware of any inverter that has built-in pre-charge resistor/relay. It's simple enough manually pre-charge with a resistor right before connecting the inverter.

I haven't done it but you may also consider using XT150 or AS150 battery connectors that has a pre-charge resistor built-in.

 

[stopcrazypp]

I'm not aware of any inverter that has built-in pre-charge resistor/relay. It's simple enough manually pre-charge with a resistor right before connecting the inverter.

I haven't done it but you may also consider using XT150 or AS150 battery connectors that has a pre-charge resistor built-in.

Yeah, when I looked around for my 1000W pure sine inverter, I didn't find any that listed that as a feature. I built a disconnect switch with a precharge circuit using the plans here:
Inverter Disconnect Switch with Precharge

 

[PianoAl]

This vid makes the point that buying a F150 Lightning may make more sense than a power wall.

Too bad we can't do that.

Do you think that any future modification, software or hardware, could allow anything similar with our existing Teslas?

 

[n2mb_racing]

This vid makes the point that buying a F150 Lightning may make more sense than a power wall.

Too bad we can't do that.

Do you think that any future modification, software or hardware, could allow anything similar with our existing Teslas?

Yes, it should be possible to pull power from the battery using the DC fast charging connector and an external inverter. But, Tesla software would have to allow it. Something like this:

Electric vehicle charger Quasar 2 bi-directional Wallbox

wallbox.com

 

[otherslackjaw]

Do you think that any future modification, software or hardware, could allow anything similar with our existing Teslas

I'm reasonably confident that at some point Tesla will offer V2X on new cars. I hope they change their stance on it before too long as it's going be so important to the future grid.

 

[David L]

Can you recommend an inverter that's plug and play? Ideally I don't want to have to add on relays and resistors to slow the inverter from pulling too much power at the start.

Smaller inverters don't pull enough current to trip the overcurrent detection mechanism. I put together a pre-charge circuit, then realized that I was able to directly connect a BESTEK 500W pure sine inverter to my '18 Model 3 using the included clamps, without doing anything special. Obviously, YMMV, because I don't know if the current limiter is configured the same in all models.

 

[stopcrazypp]

Smaller inverters don't pull enough current to trip the overcurrent detection mechanism. I put together a pre-charge circuit, then realized that I was able to directly connect a BESTEK 500W pure sine inverter to my '18 Model 3 using the included clamps, without doing anything special. Obviously, YMMV, because I don't know if the current limiter is configured the same in all models.

Whether it trips depends on how large the precharge capacitor is on the inverter and also the resistance on the wire. By buying a lower power inverter, usually it means the capacitor is smaller and resistance on the wire is higher (given typically wires included are thinner), which reduces the current pulled during start.

 

[PianoAl]

My solution avoids any risk to the car (three power outages so far in December. Power is currently out and my internet is powered by this system:

 

[rootusrootus]

That is a more typical solution that does not involve the EV, sure. But in 2022 I wouldn't waste that kind of money on an expensive lead acid battery.

 

[miimura]

That is a more typical solution that does not involve the EV, sure. But in 2022 I wouldn't waste that kind of money on an expensive lead acid battery.

The main benefit to that kind of setup is that you can power the surge load from the external battery and recharge it slowly and continuously from your EV. Whether the external battery is lead-acid and separate like that, or lithium, or part of an integrated battery / inverter / mobile device charging system doesn't matter.
If you have a setup like that but only charge it from utility power, you've basically built a UPS. The main benefit in that case is that you can choose any size battery you like.

 

[PianoAl]

The main benefit to that kind of setup is that you can power the surge load from the external battery and recharge it slowly and continuously from your EV.

Excellent idea. I didn't think of that. What would you use to connect it?

 

[cali8484]

My solution avoids any risk to the car (three power outages so far in December. Power is currently out and my internet is powered by this system:

Not sure what risk you are concerned about but the DC-DC converter is designed to provide power safely without damage to the car. Tesla mobile service uses it for their power tools. I have used it with proper settings for provide 1000W+ for hours with any issue.

 

[PianoAl]

Not sure what risk you are concerned about but the DC-DC converter is designed to provide power safely without damage to the car. Tesla mobile service uses it for their power tools. I have used it with proper settings for provide 1000W+ for hours with any issue.

Just scared by the text in the manual: "Caution: Do not use the Battery as a stationary power source."

Perhaps I'll rethink that some day.