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dspray

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Thanks for sharing! I’m planning a manual setup - transfer switch to an input, which could either be via Rivian, small battery, and/or generator (all of which we own today). I like the automated transfer switch setup you installed - very nice.
Thanks for your kind words and I am glad that you found it useful!
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dspray

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I did essentially the same instead of going with sunrun, except I used hybrid solar inverters (with auto xfer) to be able to pump out 20kW peak, charge it via solar, and have it hooked up to a UL listed 30kW backup battery bank. (All 30% eligible)

I then have a separate input that directly charges the battery bank which I can use my R1T or the Lightning to recharge. During the day it recharges from Solar and I’ve got excess to top off the trucks. During the night it runs off the bank and if it draws to 50% it calls for a “generator” which is a relay to enable the input from the truck.

For anyone looking to draw bigger loads or go longer that would be the way to go. Even if Rivian launches an integration system you can wire it up to just take care of the buffer bank.
That is awesome, well done!
 
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dspray

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Does this 2-battery setup start/run your home Air Conditioner also? If so, do you know what kind of amp draw (LRA) your unit pulls at startup?? I assume you have a soft start of some kind on the A/C if your backup can run it…

Really savvy to bridge/stagger the load between 2 batteries so you don’t black out every time the generator would need a refill.

How long would it take to recharge one battery (empty to full) from a Rivian 115ac outlet?
This 2-battery setup does not run my home AC because of the LRA. I don't recall what the LRA is, but all 3 of the compressors have 40-amp dual-pole breaker and that was too much for this setup. I am kind of thinking of this as a 2-part plan. This "basic setup" will ensure critical loads. Once Tesla gets the Virtual Power Plant (VPP) fully operational, I plan to do solar and a big (100KWh) PowerWall set up. Also, I am waiting for LFP chemistry in the powerwalls. So, I am probably a year away from the solar and power wall.

Also, a really cool thing about the Ecoflow is they have like a $1200 generator that recharges the battery and then the batteries power the various loads. It appears to take about 2.5 - 3 hours (i.e. 3.6 KWh battery divided by about 1200 watts from the Rivian. For some reason, the battery does not accept 1500 watts from the Rivian and am still playing with the maximum wattage it will accept.
 
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dspray

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Dave, this is a very clever set up! Thanks for sharing. I think most people imagine plugging in the BEV and it "just works" powering the entire house, but as you said that's not entirely true. This set up requires some manual work, but I think this would cover a majority of people's critical loads (and budgets!)

The portable/mini power station market seems to be heating up, I see them everywhere now. Is EcoFlow the only one you are aware of with a smart panel?

Appreciate sharing the links. In the Houston area too! I'll be sure check out Electrical Panel Experts if I need to do panel work.
Ecoflow is the only one I know of with the smart panel. Electrical Panel Xperts (without the "E") are great! Glad to meet another Houstonian!
 
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dspray

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I would love to find the clown that wired my house. Actually 2 clowns: the first when the house was built and the second when the basement was finished. Does that make it a circus?
Yes, I think 2 clowns makes for a circus!
 

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This 2-battery setup does not run my home AC because of the LRA. I don't recall what the LRA is, but all 3 of the compressors have 40-amp dual-pole breaker and that was too much for this setup. I am kind of thinking of this as a 2-part plan. This "basic setup" will ensure critical loads. Once Tesla gets the Virtual Power Plant (VPP) fully operational, I plan to do solar and a big (100KWh) PowerWall set up. Also, I am waiting for LFP chemistry in the powerwalls. So, I am probably a year away from the solar and power wall.

Also, a really cool thing about the Ecoflow is they have like a $1200 generator that recharges the battery and then the batteries power the various loads. It appears to take about 2.5 - 3 hours (i.e. 3.6 KWh battery divided by about 1200 watts from the Rivian. For some reason, the battery does not accept 1500 watts from the Rivian and am still playing with the maximum wattage it will accept.
Fwiw, the great Texas Snowpacalypse of 2/2021 was the final straw for me re ERCOT reliability. Didn’t have the courage to go 5-figures with a dedicated standby gen, for something that could never happen again. Priced out all the options and ended up going with a high-watt portable gen with low THD (<5%), plus an Interlock Kit with an external 50A feed to my main breaker...

But the only way to get the AC to clear the LRA was a soft start, of course. Talked to a number of Electricians/Generac installers and most of them seem to like Hyper Engineering Sure Starts (https://www.electricgeneratorsdirect.com/Hyper-Engineering-SS1B16-32SN-V230/p99614.html) to knock down the LRA. After install, I went from around 70A LRA to less than 30A LRA (measured max on multiple starts), which means even a smaller 30A Gen (without a 50A plug) could still turn over the compressor! Also stopped the flicker in the house lights during high-amp draws. Pretty cool.

Sorry for the thread drift, but I’m wondering if a single EcoFlow could be wired in concert to “bridge” my Generator, providing full baseline (low amp) power for shorter brownout periods & preventing blackouts when I need to set up/refuel the gen in an extended outage.
 

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Daily vampire drain = 2-3% or approximately 2500-4000W/day. It stinks but you’ll draw that in about 2 hours using this setup anyway.
Closer to 4-5% when ambient < 25°F -- Literally the worst thing about the Rivian ownership experience.
 

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Hi All, I have created a "Bi-Directional Charging" work-around for a Rivian.

This video walks you through what I have done and how to replicate:

.

The cost was about the same ($9,000) as preparing my house for the Ford Lightning bi-directional charging setup. But to me this is a far better setup than the Ford for several reasons:

1. I did not really want a Lightning.

2. The Lightning solution works only when the Lightning is at home.

3. It works only with a Lightning.

4. It turns out that for many houses, the Lightning CANNOT provide "whole home" backup. Rather, it may only be able to do "critical loads".

5. I believe that the cost to install the Lightning hardware is NOT eligible for the 30% home battery tax credit whereas I believe this solution IS eligible. This is not tax advice, check with your tax professional.

This video replicates how the critical loads could be powered for more than a month, using the 2 Eco Flow batteries plus a Rivian.

If any of your find this interesting and want to learn more, I am happy to have a phone call or facetime call to answer any questions.
Interesting and nice work, however, the Rivian DC to AC converter (inverter) has been tested and reported to be highly inefficient- 30% loss from HV pack to 120v plug. Also, the feed to your two batteries is minuscule as compared to the load on the backup system. For these reasons, not really a viable solution.
 
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dspray

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Interesting and nice work, however, the Rivian DC to AC converter (inverter) has been tested and reported to be highly inefficient- 30% loss from HV pack to 120v plug. Also, the feed to your two batteries is minuscule as compared to the load on the backup system. For these reasons, not really a viable solution.
Thanks for the insight on the 30% loss on the Rivian conversion. But even with that loss, that drops the "usable" power from 125 kwh to about 85kwh. I would respectfully disagree on your comment that the feed to the batteries is miniscule compared to the load. A single 3.6Kwh battery will power our 10 critical loads for about 12 hours WITHOUT conservation and about 24 hours with conservation. It takes about 2 1/2 hours to charge one battery from empty to full (3.6 kwh) So the battery charging speed is about 4 to 8 times faster than the battery discharge speed.
 

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Nice video. I have Solar from Tesla (actually from SolarCity before they got bought by Tesla) and have wavered on the PowerWalls for a long time. The thing is I have a Honda 6500W generator and its wired in. I have to manually switch it over when I lose power but with the tank and 2 cans of gas I can run for a long time. Generator runs great and is ~20 years. They cost about $3K now, electrician to set it up wasnt bad. Nothing really wears out. While I like the whole battery thing, I'm not sure it makes the most financial sense for protection from power outages unless you need everything automated for medical needs etc.
 

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dspray

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Nice video. I have Solar from Tesla (actually from SolarCity before they got bought by Tesla) and have wavered on the PowerWalls for a long time. The thing is I have a Honda 6500W generator and its wired in. I have to manually switch it over when I lose power but with the tank and 2 cans of gas I can run for a long time. Generator runs great and is ~20 years. They cost about $3K now, electrician to set it up wasnt bad. Nothing really wears out. While I like the whole battery thing, I'm not sure it makes the most financial sense for protection from power outages unless you need everything automated for medical needs etc.
Thanks Rob. Those are all good points.
 

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This is pretty cool, but I can't ever see myself giving up my standby 22kw Generac. It powers my entire house non-stop and automatically about 30 seconds after the utility power goes out.

In September 2021, we had a rare tornado here in NJ and my power was out for almost five days. My Generac paid for itself during that one power outage alone.

But I do think running the house on a battery is a cool idea for those short outages.
 

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Interesting setup, but the additional conversions from DC to AC and back to DC irk me a bit. The Ecoflow system is pretty cool on its own though.
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