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

[Jim Lewis]

I'm glad you shared this, because it reinforces that my intended plan is probably a smart course of action (Yay me!).

I was planning on having SunRun install a SPAN panel at the same time as the rest. The span panel is the "smart breakers" solution you speak of, that will auto-shed loads via software controls, replacing the need for critical load sub-panels.

It's worth mentioning that part of my reasoning for the SPAN panel is because a full solar install is next on the agenda, so having the SPAN panel in place is prep for that.

I asked Sunrun about this possibility today. They said, "No-Can-Do, because a SPAN panel is incompatible with the Ford/Sunrun HIS system." The person I spoke to, who was just relaying feedback from the design folks, also said that a SPAN SMaRT panel is not compatible with their solar system installs, either. They would love it to be so, but, unfortunately, it's not. They've acknowledged my desire for a true "Whole Home Backup" and say they're looking into other possibilities for me.

So you have natural gas feeding something in your house, but that item won't blow up but a generator might? Quite scary that an MD thinks that.

Good thing money does matter.

My wife is unhappy with either the Ford/Sunrun HIS or gas generator backup. She's basically afraid the job work for either one will muck up our house and prefers a quiet battery backup to a noisy gas generator as the lesser of two evils (on the battery backup, she's told me, "Just don't have them cause the house to burn down with a wiring screwup."). A few years ago, we had our house reroofed after a hail storm with premium architectural shingles from what used to be San Antonio's premium roofing company. They screwed up sealing one particular upper roof valley, and our roof leaked down through the 2nd floor into our first-floor master bedroom during a torrential rainstorm. So, it's that sort of aversion, that when you go to "improve" the house, the contractor finds a way to degrade your property and expose you to risks you didn't have before. My sister in MA had a BIG gas generator put in and had to have a much larger gas delivery pipe installed to support it. The natural location for our generator would be not too far from our kitchen window and unlike gas used inside the house, you have the gas in a machine outside exposed to the elements, insects like fire ants, all the lizards and chameleons around the house, etc. So when a contractor can't put an electrical panel on the house far enough away from the gas meter to begin with and can't supply us with a panel in which the inside cover doesn't begin to rust away after 33 years on the job outside, is it unreasonable that someone might distrust the new install of a big, noisy gas-consuming device outside her kitchen window? (My wife is no dummy - she had a 4.0 GPA in the UC-Berkeley undergrad premed program, which is cutthroat-competitive, and got an interview at Harvard Med School, where the interviewer actually told her, "You realize you actually have next to no chance to be admitted because you're a foreign student?" To which she snapped back, "Then why are you wasting my time and yours interviewing me?!" She might have some similarly choice words for her critics here).

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[RickLightning]

Batteries in a house used for backup power aren't exactly zero risk either.

But I hear you on contractors. I watched the install team for our generator like a hawk, and they still screwed things up. Owner of company came and apologized.

 

[HaroldCal]

I asked Sunrun about this possibility today. They said, "No-Can-Do, because a SPAN panel is incompatible with the Ford/Sunrun HIS system."

Yep, I got the same line from them. What's crazy is that SunRun is listed as a 'partner' on the SPAN.io website. It's like "How are you a partner, if you claim that the SPAN panel isn't compatible with anything you sell?"

But based on the recent video from Transport Evolved, I can see why they are not supporting it with the HIS yet. It would appear that the HIS is barely working in production so far. They don't want to add another variable.

 

[Jim Lewis]

Batteries in a house used for backup power aren't exactly zero risk either.

That's the wife's view, too, as I noted at the start of my reply to you above. The Sunrun sales person, when he was explaining the need for a critical loads sub-panel, said, "We don't want anything to blow up." In retrospect, I interpret his remark to mean if one's system draws too much power from the truck, the battery will possibly dangerously overheat, catch fire, explode. So, I think it's that possibility, not just possible damage to the charge capacity of the truck battery, that makes Sunrun so conservative on the number of circuits allowed to be connected to the truck.

The e-mail reply from Sunrun on SPAN panels was the following, with the "update" business holding out the possibility of future compatibility:

Unfortunately, we are not able to install a SPAN panel with the equipment. The reason for this is that SPAN is not compatible with the Delta equipment. Span would need to push out updates in order for it to be compatible which has not happened.

 

[Maquis]

That's the wife's view, too, as I noted at the start of my reply to you above. The Sunrun sales person, when he was explaining the need for a critical loads sub-panel, said, "We don't want anything to blow up." In retrospect, I interpret his remark to mean if one's system draws too much power from the truck, the battery will possibly dangerously overheat, catch fire, explode. So, I think it's that possibility, not just possible damage to the charge capacity of the truck battery, that makes Sunrun so conservative on the number of circuits allowed to be connected to the truck.

The e-mail reply from Sunrun on SPAN panels was the following, with the "update" business holding out the possibility of future compatibility:

Your interpretation isn’t correct. The inverter is the limiting factor on power drawn from the truck. It’s something like 11 KW. When driving the truck, the battery is capable of supplying over 400 KW.

I think “We don’t want anything to blow up” Is just hyperbole.

 

[Jim Lewis]

The inverter is the limiting factor on power drawn from the truck.

I wonder if the inverter or the MID/WHB is also limiting when the system is running on power from the grid? I haven't been able to deciper the wiring diagram that I posted above for the FCSP/HIS setup, but isn't power having to pass through one or more of those HIS devices when the grid is powering the critical loads sub-panel?, i.e., when there is no power outage. Perhaps if they only designed the circuitry to support up to a 40-amp draw when powered through the truck battery, there is the same limit when the critical loads sub-panel is being supplied by ac current from the grid? Then, Sunrun's worry would be that the user would not be thinking very much about the limited power consumption allowed by the critical loads subpanel wiring under normal operational conditions when there's no outage.

One problem with dealing with Sunrun is that I never get to speak to people really technically in the know about their system. There's always a middle-person relay ("manager"), who's about as clueless as I am about electrical circuits and equipment... I guess that way, they don't have a highly paid person wasting time on the phone with customers ....

 

[Maquis]

I wonder if the inverter or the MID/WHB is also limiting when the system is running on power from the grid? I haven't been able to deciper the wiring diagram that I posted above for the FCSP/HIS setup, but isn't power having to pass through one or more of those HIS devices when the grid is powering the critical loads sub-panel?, i.e., when there is no power outage. Perhaps if they only designed the circuitry to support up to a 40-amp draw when powered through the truck battery, there is the same limit when the critical loads sub-panel is being supplied by ac current from the grid? Then, Sunrun's worry would be that the user would not be thinking very much about the limited power consumption allowed by the critical loads subpanel wiring under normal operational conditions when there's no outage.

One problem with dealing with Sunrun is that I never get to speak to people really technically in the know about their system. There's always a middle-person relay ("manager"), who's about as clueless as I am about electrical circuits and equipment... I guess that way, they don't have a highly paid person wasting time on the phone with customers ....

Grid power passes through the MID to get to the subpanel, but I’d think that’s simply a transfer switch with a rating plenty high enough for the subpanel loads.

The point of my first post was that backup power will in no way overtax the truck battery.

 

[Jim Lewis]

Grid power passes through the MID to get to the subpanel,

But if the wiring from the MID to the critical loads sub-panel (or whatever sub-panel you want to hook up the MID load to) only supports ~40 amps, that could be a limiting factor. I remember there is a 50-amp fuse somewhere in there (not sure if it's the inverter or the MID), but that could be the limiting factor (and does one have to disassemble the device it's in to replace it?).

The San Antonio electrical inspector I talked to on Monday (2/13) said that 50-amp fuse is in there by NEC code to protect the wiring, not necessarily the truck, but if that fuse is at least on the FCSP to load sub-panel branch route, my view is they should let me risk blowing that fuse as often as I want if they're not going to put in a more conservative 40-amp breaker somewhere along the same path to the existing sub-panel I'd like to support (presumably between the truck and the inverter). So if the truck battery can continuously supply 400 kW on the road, as you say, the risk that Sunrun must be worrying about is damaging the limited power capacity of the HIS system as designed to support a limited critical loads sub-panel.

A further thought on the 400 kW power - that's in circuits to the motors. Stepping back a bit further, maybe Ford did not design the circuitry in the FCSP or the 240-volt outlet in the bed to support more than 9.6 kW (40 amps), so maybe that's a big part of the problem?

Edit_Update: The MID/WHB device supports up to 200 amps input or output. The backup-power thread says it's a basic code violation (and foolish) to have a source that can't supply anywhere near as much power as a panel it feeds might draw.

 

[GolfJRM]

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.

Has there been anyone not disgruntled with Sunrun?

 

[Maquis]

But if the wiring from the MID to the critical loads sub-panel (or whatever sub-panel you want to hook up the MID load to) only supports ~40 amps, that could be a limiting factor. I remember there is a 50-amp fuse somewhere in there (not sure if it's the inverter or the MID), but that could be the limiting factor (and does one have to disassemble the device it's in to replace it?).

The San Antonio electrical inspector I talked to on Monday (2/13) said that 50-amp fuse is in there by NEC code to protect the wiring, not necessarily the truck, but if that fuse is at least on the FCSP to load sub-panel branch route, my view is they should let me risk blowing that fuse as often as I want if they're not going to put in a more conservative 40-amp breaker somewhere along the same path to the existing sub-panel I'd like to support (presumably between the truck and the inverter). So if the truck battery can continuously supply 400 kW on the road, as you say, the risk that Sunrun must be worrying about is damaging the limited power capacity of the HIS system as designed to support a limited critical loads sub-panel.

A further thought on the 400 kW power - that's in circuits to the motors. Stepping back a bit further, maybe Ford did not design the circuitry in the FCSP or the 240-volt outlet in the bed to support more than 9.6 kW (40 amps), so maybe that's a big part of the problem?

If the installation meets the NEC, everything between the main panel and the subpanel must be sized so it’s protected by the breaker in the main panel that’s supplying the subpanel.

When running home backup, the truck battery is simply connected to the HIS inverter via the CCS port. We know we can charge up to 175 KW via CCS, so nothing in the truck is getting overtaxed.
The onboard 9.6 KW inverter isn’t used for home backup.

 

[Jim Lewis]

The onboard 9.6 KW inverter isn’t used for home backup.

I was referring to schemes where folks want to run a cord from the 240-volt outlet in the truck bed to a plug connected or inline with a transfer switch - I'm a dummy and don't fully follow that approach. Am just illustrating that the 400 kW the battery can supply to the motors isn't available in any of the power-to-the-environment supply routes - and something is going to give there if one tries to draw too much power from the truck through one of those routes.

 

[Jim Lewis]

My latestet hare-brained suggestion to Sunrun to allow "whole-house backup" to my existing sub-panel of outlets and lights (with less than 15 kWh usage per day):

Don't wire/activate the HIS grid to sub-panel circuit. Instead, use the existing 125-amp breakered main panel to sub-panel circuit when there's power from the grid. But put a switch in that circuit that can be opened by the HIS, if that's possible, or by additional CT detectors that can detect an outage and open the added grid power switch in the existing mains to sub-panel circuit. Have the HIS circuitry only work to supply power from the truck to the sub-panel when there's an outage, and just to be sure I don't over-tax the truck/FCSP/HIS circuits by having the sub-panel want too much power, put a 40-amp breaker, presumably between the FCSP and the HIS inverter.

If such a scheme were workable, a future owner of my home would still be able to draw as much grid power as the existing sub-panel circuitry currently supports. The HIS would only be involved if there were an outage (grid power no longer goes through the HIS system), and a future owner would only have to worry about any electric vehicle they wanted to charge and how to upgrade/revise/replace my existing Rube Goldberg system.

"Great" ideas are cheap (especially when you're as ignorant as I am). Making them happen is another matter entirely!

Edit_Update: Actually, the Delta Microgrid Interconnect Device/Whole Home Backup (MID/WHB) can handle 200 amps input or output (see graphic in post https://www.f150lightningforum.com/forum/threads/backup-power.11256/post-233552). So, in my hare-brained scheme, the MID/WHB device in the HIS system should be able to provide the grid power disconnect for my existing mains to sub-panel circuit even if it were drawing the maximum 125 amps allowed by the mains to sub-panel breaker. The backup-power thread has some good educating discussion in it ( Backup Power | F-150 Lightning Forum For Owners, News, Discussions (f150lightningforum.com). One point raised in that thread is whether it's against code, or even a sane idea, to provide a source (the truck) that can't provide all the power a panel might draw - but a city inspector claimed I'd be OK if I just had a breaker the size of my source in the off-grid AC circuit from truck through the inverter to the panel. So, if I can get by with that, I'd presumably just need to have a big enough wire from the MID/WHB device to my existing sub-panel to handle up to the maximum 125 amps the sub-panel is allowed to draw when running on grid AC power.

 

[Jim Lewis]

<<<sarcasm intended>>>: Sunrun's Field Website instructions on how to set up a "Whole Home Backup."

Slide 8 at https://sites.google.com/sunrun.com/sop/work-instructions/backupmicrogrid-circuits Click on slide # in the lower left to access a list of slides.

Diagram showing relocation of only a limited number of loads from Main Panel to Critical Loads Sub-Panel (slide 10 at same link as previous slide):

You're going to be in the dark in your bedroom and bathroom... What a joke!

And even better, from slide 16 in the same set!

 

[Jim Lewis]

Hooray! I got an e-mail today implying Sunrun would let me hook up the HIS system directly to my existing sub-panel rated to draw up to 125 amps when powered by the grid (twenty-six 20-amp 120-volt circuits and a 30-amp 240-volt dryer circuit) on the provision that I will use the system in manual mode. When there is an outage, I promised to first go to the garage and flip all breakers to the OFF position. Then I said I would turn on no more than six to eight breakers at a time. If I wanted to use another circuit, I'd first turn one of the ON circuits to OFF before turning on another breaker. That way, I get my choice according to the time of day and time of year as to what circuits I want to use anywhere in the house. I don't have to put a furnace blower on a dedicated critical loads sub-panel and then have a committed circuit that's useless when it's 110 degrees outside in August in Texas, or, vice-versa, have a window air conditioner circuit in a dedicated sub-panel that's useless in the dead of winter.

Sunrun told me without giving me the details that I didn't need to worry about my sub-panel drawing too much power from the truck as the truck has means of protecting itself (I presume the same is true for the inverter and its associated circuits.

I asked Sunrun to make a legal commitment by adding the above usage plan as an approved setup and methodology to my existing contract. I recognized that, ultimately, this scheme has to meet with approval by the City of San Antonio. Hopefully, Sunrun will bring it to the City's attention in applying for a permit.

Edit_Update: Just to be clear, here is the e-mail I received from Sunrun in reply to a previous e-mail I had sent them entitled: Subject: MID/WHB Device Actually Has Power Capacity to Handle All Circuits in Existing Sub-Panel in Grid Power Mode, with the suggestion that a 40-amp breaker in off-grid mode circuit from the truck, to inverter, to the existing sub-panel would protect the truck and the inverter but allow me to use the existing sub-panel within the limits of my low, < 15 kWhr per day usage sans whole house air conditioning, stovetop/oven, and dryer.

Hey Jim,

I spoke with my team and have some answers for you!

You do have the option of selecting a manual switch to truck backup during an outage. You do this one your end, through the app once everything is installed. Additionally, you are able to manage your loads that are being backed up at one time by simply not using what the breaker is sourcing i.e. turning lights off when not in use, keeping oven turned off, etc. Your truck also has a built in feature to shut the truck off if the house does attempt to pull too much power from the truck.

All three things protect your truck and would also be up to code with the city, as that is how the plan is currently designed. Your contractor, [deleted], has already pulled the permit and expects the approval today. If there are any concerns the city has with the setup, they will address it with your contractor to make corrections.

Additionally, [contractor deleted] plans to reach out to you to schedule the installation of the charger only once they do have the approved permit. They would reach out again once they have the utility approval to install the Home Integration System to schedule that.

Let me know if you have any additional questions or concerns.

Thank you

My reply requested a contract addendum that the HIS system will be directly be hooked up to the existing sub-panel of outlets and lights and stated I will manage the system manually by turning off all loads on that sub-panel and turning on no more than 6 to 8 20-amp breakers at a time. I believe in the Ford Pass app, I get to see how much current I am drawing depending on what breakers are closed, so that should help manage usage and stay within truck limits.

 

[HaroldCal]

Hooray! I got an e-mail today implying Sunrun would let me hook up the HIS system directly to my existing sub-panel .....on the provision that I will use the system in manual mode.

That is solid good news. I have the same issue with how they are trying to force a critical loads panel. At least this tends to indicate that there is an option.

I really wanted to integrate the SPAN panel into the equation, so I could have an "automatic virtual critical loads panel". I've been following the journey of Nikki at Transport Evolved ( @Aminorjourney ) to see the outcome. But after their most recent status update video, now I am wondering if the SPAN is really ready for primetime.

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