SMA Sunny Boy capabilities

[ArtDeco]

An interesting side effect of having a flexible inverter/battery setup:

I can run my enough of my home, including 240v well pump from a 3000 watt 120v inverter generator using an “assist” function of my inverters. Honestly I could likely run the house off the smallest Honda generator because my continuous loads are less than the rated output of these really small generators.

It’s a cost and convenience thing. I use the most fuel efficient generator that is physically small and quiet…relatively.

I have gone 11 days without grid power during an outage last year on a small genie.

Could you provide some details like brand and model of inverter and battery bank? I don`t know what an assist function is .

 

[Hedges]

An inverter like Sunny Island can be programmed to draw no more than 25A, 3000W, from generator on AC input.
The inverter will put out 11kW surge for 3 seconds (22kW if two inverters wired for 120/240V split-phase), adding their output to what comes from generator. They will continue to put out 5.75kW continuous (11.5kW for two) added to the 3kW from generator. When loads are less than generator output, inverter recharges batteries.

That would be "assist".

Probably several other brands including Outback and Trace/Schneider do the same.
None of this cr*p like, "Generator must be at least 15kW"

 

[ArtDeco]

Thanks again @Hedges . I am very slowly making sense of this stuff. The solar system market has changed a lot in the 10 years since I bought my 1st system, and I never really understood my system in the first place. I still hate the idea of buying two inverters ( 1 for battery and 1 for grid) and two batteries (minimum) as well as a generator, but that appears to be the way we will have to go, even without backing up any 220 volt loads.

 

[Hedges]

Or more inverters than that, or an auto-transformer (but then you quickly exceed 120% rule if backfeeding grid.)

For grid-backup I went with AGM battery. FLA would be cheaper, not UL recognized, requires maintenance, can last longer.
Various lithium have advantages and disadvantages, bunch of teething pains for this application. But price is becoming compelling, also cycle life of a decade or more for deep nightly cycling.

Depending on what you want and what you need, wide range of solutions to choose from. Some robust, some risky (cheap brands).
For things like security and communication, could be a 12V AGM battery, charged from grid and optional PV. For some computers, stand-alone UPS. Various larger grid-backup systems for part or all of house, and full off-grid.

My system automatically backs up most loads with PV & battery. I need a way to switch off a couple unnecessary ones so small battery is sufficient for the night. I can manually connect and manage other large loads. So much PV I can run AC, laundry, etc. during the day. Grid is reliable enough I haven't automatically shed loads that could be. Sometimes the lights go out, then I do that manually.

 

[Hedges]

"Current Solar Power System - 7 kw rooftop with 24 panels and 2 inverters
Background - Retired programer looking to replace my home system with battery backup. No DIY electric experience."

What brand and model inverters?
They may be able to AC couple, play nice with a battery inverter.

 

[ArtDeco]

2 SMC Sunny Boys (3500w ? each) both were destroyed, and only 18 of the 250w panels ( maybe worth $900) survived the fire. So pretty much starting from scratch again.

 

[Hedges]

You are probably allowed to replace old equipment with other only meeting codes from back then. You may be able to buy new old stock as I did, for instance Sunny Boys for as little as $0.10/W. Sunny Islands are $3000 and up these days, although you might get by with one plus transformer(s). I would prefer two.

There are probably lower price systems available of similar wattage. Whether they are lower cost over their lifetime matters more (especially if you have insurance money for replacement.) First thing to consider is performance and capacity you need, and future capabilities desired.

If insurance pays for replacement AND you then get 30% federal credit

 

[ArtDeco]

Quite the opposite. I`m afraid. The insurance company is trying to wiggle out of paying for any appliances that were installed in the home, b/c the re construction will use all the coverage, and they claim that things installed are not covered under contents. So I will probably end up paying for it myself or going to court. The 30% credit only applies to buying a new system AFAIK, not replacing one.

 

[Hedges]

A replacement system IS a new system. Credit should apply whether you add PV and inverters to an existing system, or to a property after the old one burned up. Word is new program will apply to batteries added to existing system.

Anything attached to a building is real property. Cabinets hanging on kitchen wall are real property, furniture placed on floor is personal property.

If you were under-insured regarding value of real property then you should be able to receive 100% of policy face value and allowed code upgrades.

Be sure to stick it to them as best you can with personal property replacement coverage. What I've seen is you are paid in cash for value of what was lost, then for each individual item you document replacement of, they reimburse up to some allotment. But you can't pool two lost items and buy a higher end single item.

I think free-standing appliances are personal property, not real-property. Perhaps terms and conditions define otherwise.

 

[ArtDeco]

Yeah, it`s not just the policy terms and conditions, the state where you live matters as well, and Pennsylvania law is very favorable to insurance companies according to my lawyer. But it may all work out without going to court. Many things do. But I am trying to be prepared for a long wait (months to years) until all is settled. Their position seems to be that anything installed (other than plugging a fridge into a wall socket maybe) becomes real property.

As far as the tax credit, are you sure about that? I was told by an installer that no credit was available if adding to an existing system, but I haven`t researched that.

 

[ArtDeco]

I see the federal tax credit is available on additions to existing systems as well as a new install.

 

[Hedges]

I can't be certain about tax or legal matters.
I read "system placed in service". I could imagine that adding panels to an existing system, or replacing inverter of an existing system, might not qualify. But if you have or had a system, and you bought a new system and placed it in service, I read that as qualifying. If you later added to that system some panels you salvaged from the fire, so what?
I would consider each system that captures photons and delivers electricity to be a system. Electricity as 60 Hz AC wired to your electric panel seems like a good dividing line, and you could have more than one of those.

I would think a drop-in cooktop, clamped to the counter top, is real property. Same a built-in dishwasher and a water heater.
Slide-in range, refrigerator, laundry machines, those I could consider personal property. They may have been itemized as such when property was bought from previous owner.

If real property, unlike personal, you can probably shift around where the insurance money is spent. I shop a lot on eBay, Craiglist, and at ReStore (Habitat for Humanity's thrift store.) You could replace appliances for a fraction of new.

Much of the cost of building is the high markup each of the trades will charge you as a retail customer, compared to what they would get if contracted for a subdivision. But buying skill and quality is not easy or cheap.

 

[ArtDeco]

I can't be certain about tax or legal matters.
I read "system placed in service". I could imagine that adding panels to an existing system, or replacing inverter of an existing system, might not qualify. But if you have or had a system, and you bought a new system and placed it in service, I read that as qualifying. If you later added to that system some panels you salvaged from the fire, so what?
I would consider each system that captures photons and delivers electricity to be a system. Electricity as 60 Hz AC wired to your electric panel seems like a good dividing line, and you could have more than one of those.

I would think a drop-in cooktop, clamped to the counter top, is real property. Same a built-in dishwasher and a water heater.
Slide-in range, refrigerator, laundry machines, those I could consider personal property. They may have been itemized as such when property was bought from previous owner.

If real property, unlike personal, you can probably shift around where the insurance money is spent. I shop a lot on eBay, Craiglist, and at ReStore (Habitat for Humanity's thrift store.) You could replace appliances for a fraction of new.

Much of the cost of building is the high markup each of the trades will charge you as a retail customer, compared to what they would get if contracted for a subdivision. But buying skill and quality is not easy or cheap.

On the old saw about good, cheap, or quick; pick any two...I
am going for good and quick. Definitely not easy, but doable.

 

[Hedges]

There are many kinds of GOOD batteries today, and some very slick electronics to keep them charged up. This is an example from a company I'd never heard of ... EG4.

If you're going the route of Good and Pretty but not Cheap, people who have SolArk like it.
Complaints we read are from people who choose not to buy one, on account of similarity to overseas models under other names for a fraction the price (and questions of whether this made-in-China product is engineered in U.S. as claimed.)
SolArk may be picky about generators used with it.

I like SMA, and for similar price to high-frequency SolArk you get transformer type battery inverter, German engineering, German or US/Canada manufacturing. Support seems very slow from SMA, vs. people report great US based support for SolArk. Features and updates are a difference. I think grid related features like peak shaving are likely to be in new model SMA inverters, not software updates for existing model. I'm fine with no support if SMA never breaks and functionality as-delivered is what's needed.

 

[Hedges]

Thanks again @Hedges . I am very slowly making sense of this stuff. The solar system market has changed a lot in the 10 years since I bought my 1st system, and I never really understood my system in the first place.

Or in the case of SMA, "Sunny Island" is virtually the same as 15 years ago. Now called 6048US instead of 5048US, slightly better cooling so it produces 5750W continuous at 25 degrees C instead of 5000W. I think all take the same firmware, so older model can be updated and will talk to supported lithium BMS.

The Sunny Boys today are newer models with latest grid-support requirement, and all transformerless. Earliest models were transformer-isolated, and transformerless has been around over 10 years.

I think the older model Sunny Boys may be better for use with a generator, because they can switch from on-grid UL-1741 limits to much wider voltage and frequency. A video by SMA America says to put Sunny Boys in "offgrid" a.k.a. "Island" mode when used for grid-backup behind Sunny Island. That contradicts written instructions, and suggests there is some issue they were trying to work around.

 

[teo]

Hello everyone, I'm new here... currently I have a Chinese hybrid system 3000w, I bought it for the needs of lights and some other devices with low consumption, I have 5 panels and a 24v 375ah battery. The plan is the following, I'm interested in a combination of SMA device SB and SI(EU 220v), the plan is to add another 10-15 panels. I am interested in the combination of SB/SI as a hybrid, I would prefer to use electricity from the battery at night, and from the PV system during the day. I have a small farm, which does not require a lot of electricity, the electricity from the network often disappears for a few hours. Not to forget, my biggest hits are a little over 6kw

 

[Hedges]

So you have grid power available. Do some math on the cost per kWh over life of PV, inverter, batteries. You can size a system for critical loads during power outages, or size to supply 100% of everything. PV is relatively cheap, so over-sizing it helps with poor weather and reduces size of battery needed for one night by keeping up with loads later in the day.

You can build an off-grid or grid-backup system with SMA or other brands. Biggest software differences I think will be selecting time to draw from grid vs. battery, may not be configurable for some.

Power budget, daytime vs. night time, will let you size it efficiently. Backup generator is a cheaper way to get through occasional multiple days without sun.

Systems can cost as little as $1000 or as much as $20k+, differences in size and quality. It appears you have an inexpensive small backup system already.

 

[teo]

Дакле, имате на располагању електричну енергију. Урадите мало математике о цени по кВх током животног века ПВ, инвертера, батерија. Можете димензионирати систем за критична оптерећења током нестанка струје, или величину за снабдевање 100% свега. ПВ је релативно јефтин, тако да превелика величина помаже у лошим временским приликама и смањује величину батерије која је потребна за једну ноћ држећи корак са оптерећењем касније током дана.

Можете да изградите систем ван мреже или резервну мрежу са СМА или другим брендовима. Највеће софтверске разлике мислим да ће бити одабир времена за извлачење из мреже у односу на батерију, за неке се можда неће моћи конфигурисати.

Буџет енергије, дневни у односу на ноћ, омогућиће вам да га ефикасно одредите. Резервни генератор је јефтинији начин да прођете кроз повремене више дана без сунца.

Системи могу коштати само $1000 или чак $20к+, разлике у величини и квалитету. Чини се да већ имате јефтин мали резервни систем.

Thanks for the quick reply, I have a utility network, which has not been very reliable in the last 8-9 months, I prefer an off grid or hybrid system, I have forklift batteries at my disposal.I would also like to transfer part of the house to that new system. (ligh, refrigerator, freezer...)

 

[teo]

the idea is SB6kw and SI8.0 48v 800+ ah
there are doubts about the SMA device, everything is explained very vaguely, there are no diagrams, everything is.....
money is not important for now, what is important is that the farm is working, which is a source of income....

 

[SilverbackMP]

the idea is SB6kw and SI8.0 48v 800+ ah
there are doubts about the SMA device, everything is explained very vaguely, there are no diagrams, everything is.....
money is not important for now, what is important is that the farm is working, which is a source of income....

That's my source of anxiety too...I understand the big picture of how SMA works and the benefits, but I haven't dug into their manuals and I'm somewhat electricity illiterate (too many years away from blue collar working for the .mil as a planner/operations officer). Whereas Victron is more covered on YouTube. But I'm basically committed at this point (four Sunny Islands still in their boxes and 62 solar panels in a toy hauler, REC BMS parts on order, still firming up choices for Sunny Boy and battery purchases).