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

[SunEagle]

Right, and that's pretty much my point. I doubt anyone here would have any problem maintaining a generator (or a battery bank, or a hybrid system.) But most homeowners are not capable of getting a generator to start by spraying starter fluid in while cranking it, and most are unwilling/incapable of doing the basic maintenance to keep it more reliable than that. Most homeowners are capable of flipping a switch to turn on a backup power supply. And the price is right.

Convincing someone they need to buy a generator (with the associated maintenance requirements) or a battery bank (with the larger costs and maintenance requirements) is going to be a hard sell, especially for someone who loses power once every 20 years after a big storm. Convincing someone they need to spend $20 to get an outlet and a switch is going to be a much easier sell - and that small investment might save them a lot of money in water damage, rebuilding and food costs.

And yet telling them that a simple solution to having power when the grid goes down is to purchase the SPS option, Which IMO is misleading because they will only get power when the sun is shining and maybe 15amps max for a short period of time even though the grid could be down for days.

It would be better to invest in a good grid tie solar pv system as well as an automatically starting whole house generator. Those will not require much in the way of maintenance or costs yet can provide a lot of power anytime the grid is up or goes down.

[jflorey2]

Well of course a generator needs a minimum level of maintenance, like anything else you rely on. I try to remember to check
out my 2 decade old gen set every year; only needed it 4 times. I DO recommend you get one with an electric starter, which
makes it a whole lot easier to start while you are spraying in starter fluid to compensate for the carb & old gas you haven't
serviced in a very long time. Keep a maintainer on the battery or you will be jumping it with your car.

Right, and that's pretty much my point. I doubt anyone here would have any problem maintaining a generator (or a battery bank, or a hybrid system.) But most homeowners are not capable of getting a generator to start by spraying starter fluid in while cranking it, and most are unwilling/incapable of doing the basic maintenance to keep it more reliable than that. Most homeowners are capable of flipping a switch to turn on a backup power supply. And the price is right.

Convincing someone they need to buy a generator (with the associated maintenance requirements) or a battery bank (with the larger costs and maintenance requirements) is going to be a hard sell, especially for someone who loses power once every 20 years after a big storm. Convincing someone they need to spend $20 to get an outlet and a switch is going to be a much easier sell - and that small investment might save them a lot of money in water damage, rebuilding and food costs.

[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.

[bcroe]

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.

Well of course a generator needs a minimum level of maintenance, like anything else you rely on. I try to remember to check
out my 2 decade old gen set every year; only needed it 4 times. I DO recommend you get one with an electric starter, which
makes it a whole lot easier to start while you are spraying in starter fluid to compensate for the carb & old gas you haven't
serviced in a very long time. Keep a maintainer on the battery or you will be jumping it with your car.

Not against Secure Power, but not relying on it either. Bruce Roe

[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.

[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.

[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.

[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

[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.

[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]

Thanks for your help. Are there any options that can plug into the home electric system? I guess I'm looking for something that can keep my AC on for those yearly outages in the middle of the summer

[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.

[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.

[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...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?

[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.