Effects of clouds on your array? I'm considering SMA's Secure Power Supply inverters.

[home4]

This is not true. I just had my 5.889 kW system installed with an SMA Sunny Boy 6000TL-US-22 with Secure Power. While I await my new meter, I have played with the secure power. I took a sick day last week on an overcast cloudy day. For kicks I decided to plug in a jig saw. I ran it flawlessly for a few minutes. I then decided to run an extension cord from the secure power outlet to my entertainment center. Since both items were the only draw on the system, the Sunny Boy display lists the draw coming from the secure power. Running the jig saw for a minute was a 500 watt draw. The tv/cable box/sound bar was a 450 wall drawing which was maintained for about three hours until night was starting to fall upon the panels. The constant cloudiness kept the power at a constant rate and did not result in any shutdown/restarts until it got late. If you overload the secure power it will restart itself on it's own. No going back to the switch.

So in summation; I think the secure power supply is a great add-on. With occasional hurricanes and blizzards, I just need enough power to charge phones, laptops and perhaps run a tv or bring the internet up for a little while.

Thank you very much for your report of actual usage of the Secure Power feature. Yours is one of the only actual reports I've seen, and if you make any other experiments I would be very interested in hearing about them. While you were running these things, did the inverter say how much power was actually available from the panels? Or does it only say how much you are drawing?

[NKetch22]

Thank you very much for your report of actual usage of the Secure Power feature. Yours is one of the only actual reports I've seen, and if you make any other experiments I would be very interested in hearing about them. While you were running these things, did the inverter say how much power was actually available from the panels? Or does it only say how much you are drawing?

Today, which was a mostly sunny day, I managed to run a small beverage refrigerator from the SPS. Last time the inverter refused to provide sufficient power when the compressor kicked on. Granted, the normal power consumption of the fridge is only 0.85 amps @ 115v...Othewise, I have only maxed out the SPS at about 500 watts.

Once the grid interconnection is approved and net meter added I will try and formulate a correlation of the full PV system output into the grid vs. the SPC output.

The inverter does not indicate how much is available, only instantaneous consumption/power generated. The invert display shows the MPPT channels voltage and amp draw from each of the strings, which adds up to the instantaneous consumption.

[inetdog]

The inverter does not indicate how much is available, only instantaneous consumption/power generated. The invert display shows the MPPT channels voltage and amp draw from each of the strings, which adds up to the instantaneous consumption.

By looking at the actual panel voltage versus the theoretical Vmp for the panel temperature you can get some idea of the amount of "reserve" power in the panels. When the SPS is delivering the maximum possible output for the conditions, the Vmp x Imp product multiplied by the SPS efficiency will be the power you are drawing.
Since in the absence of partial shading the array Vmp is relatively independent of the amount of light on the panels, you will know it as that SPS draw on the panels approaches the maximum available.
The maximum current, Imp, on the other hand is almost directly proportional to the amount of light over a wide range. Most of the time the GTI function will be drawing Imp while the SPS function will be drawing less, as needed to supply the output demand, moving the operating point to a higher voltage.

[nomadh]

Thread resurrection time. I was searching for more information about the sunnyboy sps system when I ran across a very good question by some sharp guy about sps usage. I was finishing reading the post when I realized it was me this was a year and a half ago and was just hearing about this intriguing new product. I was reading because I was just experimenting with my new sunnyboy 7000tl. I'm amazed at how little info there still is on this amazing product . I have 5760 watts of LG panels on my roof now.
I've done few tests now. One was an end of day test at about 8pm. And I was generating only 100 watts. I plugged in a 60 watt light and it powered up no problem. I checked on it until it was 75 and it still powered the 60. Later I saw the light was off and the panels were down to 50 and the inverter was periodically trying a restart. Don't know exactly how much headroom it needed to power 60 watts but I'd call it good. Today I ran our older less efficient fridge. It has a start surge of about 500 watts and run about 300. It kicked on and ran just fine. I still say this is genius. Also the original reports were that this system had 0 surge capability but now I'm hearing there is some reasonable amount.
I just tried to stress test it by running the fridge near end of day. My panels were showing about 350 w when I started but I couldn't get it to fire up. My guess is it couldn't get past the 500 surge startup so I waited to long. I'm estimating that as long as the panels were still kicking out 1kw I could get it to work. If I wanted to maximize it I'd set the fridge controls on max and let it run at it nominal compressor setting of about 200w until the panels ran down to where there wasn't enough headroom. Be pretty good to have ac and fridge during a few summer brownouts. If something longterm happened that 1500 watts a day or 15 kwh a day would be nice.

[solarix]

The new SunnyBoy models (only the 5000w and 6000w have been released as of May 2016), have up'd the SPS spec to 2000w, so I think SMA has responded to the naysayers that claim it won't power very much. I agree with you that this feature gives this product a big advantage over the competition and I'm surprised no one else has copied it.....

[SunEagle]

The new SunnyBoy models (only the 5000w and 6000w have been released as of May 2016), have up'd the SPS spec to 2000w, so I think SMA has responded to the naysayers that claim it won't power very much. I agree with you that this feature gives this product a big advantage over the competition and I'm surprised no one else has copied it.....

The biggest issue with the SMA product is that most places when the grid goes down it is due to bad weather and clouds. Therefore no sun.

Now if you live in an area where there are brown outs or rolling black outs a system like the SMA will certainly help you with some power to run critical loads. I just wouldn't bank on that power being there all the time when the grid goes down.

[huge]

Can you plug the SPS into a wall outlet to get electricity in the entire house? Not to power everything, but just vital essentials like refrigerator and AC. Some people can't move the refrigerator to the SPS to plug it in and it would be much more convenient to just plug the thing in one outlet and get power to other parts of the house

[SunEagle]

Can you plug the SPS into a wall outlet to get electricity in the entire house? Not to power everything, but just vital essentials like refrigerator and AC. Some people can't move the refrigerator to the SPS to plug it in and it would be much more convenient to just plug the thing in one outlet and get power to other parts of the house

Short answer. NO

That SPS has a dedicated plug and you should only use a cord plugged into it to power something. Any type of "backfeed" to the house using a receptacle would be dangerous.

[huge]

Are there any better options to provide me with back up power in case of a power outage? How about something like this:

http://www.amazon.com/PowerPro-56101-Starting-Portable-Generator/dp/B00J261PGQ/ref=zg_bs_5006643011_1

Even though the SMA with the SPS looks like a good option, and it is actually $1000 cheaper than solaredge according to the quotes I got, I have some shading issues and not sure if the lower price will make up for the lost production. How can I find out how much the production difference will be for my set up with SMA vs solaredge?

[SunEagle]

Are there any better options to provide me with back up power in case of a power outage? How about something like this:
http://www.amazon.com/PowerPro-56101...s_5006643011_1

Even though the SMA with the SPS looks like a good option, and it is actually $1000 cheaper than solaredge according to the quotes I got, I have some shading issues and not sure if the lower price will make up for the lost production. How can I find out how much the production difference will be for my set up with SMA vs solaredge?

Just about any small portable generators will be less costly to use as an emergency power source then going with batteries and solar.

To increase your odds you might want to look at both a gasoline and a bottle gas type generator. I have both and at least I know I can find one or the other fuel to run a generator.

[SunEagle]

The only safe way to provide power to your home if the grid goes down would be to install a whole house generator with a transfer switch. The switch will ensure you can't back feed the grid and hurt someone.

A whole house generator can run on bottled or natural gas. And surprisingly the cost is about $3000 to $5000 for a 15kw generator and storage fuel tank

As much as I wish solar was the answer it is not when you consider the need of an emergency power source.

[huge]

How about a transfer switch that connects the generator as well as the solar panels, so that the solar gives you direct electricity and off from the grid during blackouts. That probably would be ideal

[NYHeel]

My understanding is that a 15 kW whole home generator will cost about $10,000 installed. Between the plumbing costs needed for the gas line and the electrical costs for the transfer switch, you usually end up in the 8000-10000 range. Well at least here in the NYC metro area where everything is expensive.

[Engineer]

The new SunnyBoy models (only the 5000w and 6000w have been released as of May 2016), have up'd the SPS spec to 2000w, so I think SMA has responded to the naysayers that claim it won't power very much. I agree with you that this feature gives this product a big advantage over the competition and I'm surprised no one else has copied it.....

I guess ... spinning on what SunEagle says, it's likely useless when you want it (storm/etc). And say your in a situation where you can use it, what for? Don't need lights if you've got solar, can't generated much power for electric heat if you need it some low production winter day. Well there's refrigerators, but do you really want to pull it and run an extension cord? OK I guess you have the option at least, if there's enough power. If it was me I'd get a generator.

[jflorey2]

And say your in a situation where you can use it, what for?

Refrigeration, sump pumps, recharging cellphones, recharging power tools, fans for drying out a house. After Sandy I knew several people who had solar who lost the contents of their basement and/or could not do basic repair around their homes due to lack of power.

OK I guess you have the option at least, if there's enough power. If it was me I'd get a generator.

Generators are great. But you have to maintain them even if they're not used often; a generator that has been sitting with the same oil and fuel for ten years is useless when a long blackout arrives. (And you'll discover as soon as the storm hits that replacement parts, and even replacement generators, are suddenly very hard to come by.)

The benefit of the Secure Power supply is not that it's a reliable 24/7 source of power, or that it's just like a generator. It is that it is effectively free and will be available when few other sources of power are - and no maintenance is required to ensure it remains available.

[adoublee]

Ice storms are the most significant reason for extended outages in my area. Heat, which most people consider heat one of the most basic necessities for survival, is usually needed during these periods. Natural gas service is common and typically unaffected by an ice storm. So on top of the items jflorey2 listed, being able to run the blower fan of a furnace could be huge.

[SunEagle]

Ice storms are the most significant reason for extended outages in my area. Heat, which most people consider heat one of the most basic necessities for survival, is usually needed during these periods. Natural gas service is common and typically unaffected by an ice storm. So on top of the items jflorey2 listed, being able to run the blower fan of a furnace could be huge.

Good point. Although I would want to be able to run that fan any time of the day or night.

I will say it again. While having the ability to generate power from a solar pv system when the grid is down using the SMA feature is a nice option but not practical due to when the grid does go down is usually associated with the lack of sunlight.

[SunEagle]

Refrigeration, sump pumps, recharging cellphones, recharging power tools, fans for drying out a house. After Sandy I knew several people who had solar who lost the contents of their basement and/or could not do basic repair around their homes due to lack of power.


Generators are great. But you have to maintain them even if they're not used often; a generator that has been sitting with the same oil and fuel for ten years is useless when a long blackout arrives. (And you'll discover as soon as the storm hits that replacement parts, and even replacement generators, are suddenly very hard to come by.)

The benefit of the Secure Power supply is not that it's a reliable 24/7 source of power, or that it's just like a generator. It is that it is effectively free and will be available when few other sources of power are - and no maintenance is required to ensure it remains available.

Maybe there is no maintenance but you still have to turn that SPS feature on and off manually when the grid goes down and then comes back. It is not automatic like a whole house generator can be.