Elderly Couple Disgruntled with Sunrun's "Whole Home Backup" Home Integration System

[Jim Lewis]

I've gotten a bid from Sunrun to install the Ford Charge Station Pro and the Home Integration System and have signed the contract with the option to cancel up to the installation day. Yet nowhere in the contract do they state exactly what they're going to back up. I've told them if they don't give me a suitable answer, I will cancel. I thought other forum members might find the specifics amusing and also be able to offer me some good advice.

To provide context and back up a bit, my wife and I are an elderly couple in our 70s. We have a ~3400 sq ft house. Our kids are middle-aged adults and long gone. They live far away, and we visit them. They don't visit us. We live frugally, don't throw large parties, have many house guests, etc. We live as if we owned a 1,000 sq ft house. All the heavy-duty electrical stuff, the oven, and stovetop, and the two AC compressors are on the main panel. Everything else, except for the electric dryer, on the sub-panel, are electrical outlets and lights. The blowers on the two gas furnaces are powered on the subpanel as well as the refrigerator/freezer, and from time to time in the winter, usually one, sometimes two 1.5 kW space heaters.

Our sub-panel has twenty-six 20-amp 120-volt breakers and a combined 30-amp 240-volt breaker for the dryer for a theoretical max consumption of 69.6 kW, whereas the main panel is only breakered for 30 kW for the sub-panel.

Perhaps here's where electrical ignorance and foolishness on my part kick in. In fall, winter, and spring months, when AC use is not a factor, our average daily electrical use is always less than 15 kWh PER DAY. And that includes the use of the electric stove top, oven, and dryer. I figured with that low consumption of power, the truck could literally back up the whole sub-panel with the dryer removed without much risk of trying to draw too much power from the extended-range battery that will come with the truck.

However, Sunrun has told me that their SOP is to break out just the circuits my wife and I deem as critical to a sub-sub-panel that is referred to in their documentation as the "backup panel" (BUP). When you look at their website setup literature, the requisite checklist sheet for backup loads testing allows for a panel that holds at most 12 household circuits:

https://sites.google.com/sunrun.com/sop/work-instructions/backup-loads-testing?authuser=0 (sign in with a Google account, see slide 12 by clicking on the slide number at the lower left)

Also, the required photo checklist for installation commissioning shows a panel with at most 12 breaker slots: https://sites.google.com/sunrun.com/sop/photo-checklists/ev-charger-system-checklists?authuser=0 (sign in with a Google account; see slide 20 in 2nd set of slides for EV Charger and HIS by clicking on slide number in the lower left of 1st slide)

I suggested to Sunrun that the truck with 9.2 to 9.6 kW output could easily back up our very low electrical usage if the dryer circuit were just removed from the sub-panel. If Sunrun were concerned about the ill-considered use of electricity drawing too much power from the truck, why not just put a 40-amp breaker in the HIS circuitry to the sub-panel? No response whatsoever from Sunrun so far on this suggestion.

I decided the ultimate bottom line would be the City of San Antonio electrical code inspectors. So, I spoke to a very helpful inspector on the phone today.

He suggested that putting load-dumping circuitry between the HIS and the sub-panel would be one way to have a "whole house backup" while protecting the truck from drawing too much current. He agreed that putting a 40-amp breaker in any acceptable place between the truck charger and the sub-panel would also do. But he said one of the most important elements of code inspection in San Antonio is whether or not the wiring scheme used meets the recommended wiring diagram of an OEM. He did suggest that if Sunrun wasn't willing to customize my installation, I should find another installer, but it seems that meeting the wiring setup recommended by the OEM is going to be a tough nut to crack. The inspector did say that all the Sunrun installations that he's inspected (presumably mostly solar panels) were well done.

I've forwarded the electrical inspector's comments to Sunrun, but they haven't responded yet. It does seem like with Sunrun that you're paying a lot but getting a little, at least in customizing an installation to fit a customer's electrical usage. Another complication that I didn't discuss with the inspector and perhaps the reason Sunrun doesn't employ the two overprotection ideas I'm considering is that both load dumping circuitry and big breakers can generate large transient voltage spikes, according to Internet articles. There might be a need to provide downstream surge suppression that might wear out eventually. So, if anyone has any good advice on any of the above for an electrical ignoramus, I'd much appreciate it.

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[Henry Ford]

I'm not sure I can address all your issues but I have some big picture thoughts.

I'm a little surprised they want to break off certain circuits to a sub-panel but it makes sense. If the CSP is on a 100 amp breaker, the wiring is setup for a 100 amp panel. There's probably more to it than that but that's my initial thought.

Do you have natural gas? To me a whole home natural gas generator makes a whole lot more sense than using your transportation as a generator. For the cost of the Sunrun backup system or less you have a system that works as long as NG is flowing and you can still change your truck (maybe: you might have to turn down the amperage). If you'd rather have a battery backup system there are stand alone systems that don't require losing your transportation.

Anyway, another way to do it is a manual transfer switch panel. This would allow you to use the Pro Power Onboard feature of your truck to power a select number of circuits of your house and still allows you or a future owner the option to use a generator. I'm guessing this is less comprehensive than you want but thought it worth mentioning. This is my plan after exploring the value proposition of different options.

 

[ChrisCon]

What was the price of the bid from Sunrun ?

 

[jimfigler]

I agree with @Henry Ford . if you are going to drop that kind of money and you have access to natural gas just get a whole home generator. the generator will be there for many years the Lightning may not.

 

[RickLightning]

I guess I don't know what "elderly couple" has to do with anything. I don't see anyone taken advantage of, I don't see any elderly-specific issues. Lots of people live by themselves in a house.

+1 on a whole house generator. Lightning solution is currently too expensive to implement, has to be charged, and in the garage. When you're visiting the family that won't visit you, driving your new Lightning, your house has no backup power.

 

[MM in SouthTX]

Would there be a problem with powering a whole house panel but leaving all breakers off except the lights and plugs? That way the truck could light up the house and keep the food from spoiling for the cost of a transfer switch and some wiring. Use the 240 in the bed.

 

[Grumpy2]

Would there be a problem with powering a whole house panel but leaving all breakers off except the lights and plugs? That way the truck could light up the house and keep the food from spoiling for the cost of a transfer switch and some wiring. Use the 240 in the bed.

Safety is the biggest problem. You need a positive method of isolation of your house from the grid.

 

[MM in SouthTX]

Safety is the biggest problem. You need a positive method of isolation of your house from the grid.

That’s why I mentioned the transfer switch.

 

[Grumpy2]

A quick review, a 200amp transfer switch is pushing $800 for materials alone.

 

[Monkey]

To add a bit more to this... SunRun should have clarified which circuits will be moved to the Back-Up Panel (BUP) when they did their inspection and put together the quote and would have discussed all this with you. Typically, you would move the critical stuff to the BUP, as the power available for backup is limited. Things like furnace, water heater, refrigerator, critical lights, etc.. They're probably intending to do that as work is being done, but SunRun has been notoriously sloppy and poorly managed throughout all of this HIS installation with Ford and are known to really miss the mark on their quotes.

The current home backup system involving the truck has the shortcomings already mentioned in that it requires the truck there and charged up to be a functional backup. The cost of this installation is currently not all that economical. Nice idea, but if I'm going to install a home backup for this price, I want something that will always be available so my pipes don't freeze if my truck isn't there. So in terms of cost and availability/ reliability, the backup generator makes a whole lot more sense right now. Even a backup battery isn't out of the question with the prices I've seen SunRun quoting.

Whether you use the truck or not, you will almost certainly be in a situation with a Back-Up Panel. The size/output capability of the backup generator will determine the size of your BUP or what capacity you have.

Home backup from the truck / Ford Charge Station Pro is a sustained 9.6kW capacity. It feeds back to the panel/BUP via a 50A circuit.

 

[MM in SouthTX]

Safety is the biggest problem. You need a positive method of isolation of your house from the grid.t

Looking for answers about whether there is a problem with doing this, as in functionality, not an economic analysis. Thank you though.

 

[Henry Ford]

Looking for answers about whether there is a problem with doing this, as in functionality, not an economic analysis. Thank you though.

My notoriously cheap Dad installed a 30 amp wire on a 50 amp breaker in his main panel. The "safety" procedures are written on the panel. It works but is extremely not safe. Now he's gone and my Mom or whoever is helping her has to complete all the steps in the right order to power her house.

My point is, yes this works but you or anyone else shouldn't do it. Code isn't written for you, it's written for the next homeowner.

 

[MM in SouthTX]

My notoriously cheap Dad installed a 30 amp wire on a 50 amp breaker in his main panel. The "safety" procedures are written on the panel. It works but is extremely not safe. Now he's gone and my Mom or whoever is helping her has to complete all the steps in the right order to power her house.

My point is, yes this works but you or anyone else shouldn't do it. Code isn't written for you, it's written for the next homeowner.

Okay. I will have to guess what the code violation is. Are you saying that it's a code violation to allow input from the truck to a panel that can draw more than what the truck supplies? And that is the reason that a "critical load panel" or a subpanel needs to be installed? That would make sense, if it is dangerous to try to pull more from the truck than it can supply.

 

[Tony Burgh]

Okay. I will have to guess what the code violation is. Are you saying that it's a code violation to allow input from the truck to a panel that can draw more than what the truck supplies? And that is the reason that a "critical load panel" or a subpanel needs to be installed? That would make sense, if it is dangerous to try to pull more from the truck than it can supply.

Wouldn’t the truck breaker trip?

 

[MM in SouthTX]

Wouldn’t the truck breaker trip?

That would be a good safety mechanism to keep me from trying to run the air conditioner. I just want the lights and plugs to work though. Keep my internet, lights and refrigerators working in temporary outages. I would leave the big breakers off.

Finally, after 3.5 months, I am getting a 240V 50 or 60 amp plug in my garage. I'm selling the FCSP. The portable charger at 5% charge per hour is good enough for me. In fact 120V and 0.8% per hour has held up for my driving except for a few times at a DC fast charger. I just plugged it in most nights and woke up with 10% more charge every day. Enough for the average 25-35 miles/day I drive.

I will discuss code and options with the electrician tomorrow.

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