SMA Grid - Tie inverter with Secure Power ??

[Murby]

I have a question about the secure power outlet on SMA inverters. They say its a 2000 watt power supply if the panels can deliver the energy.

My question is what kind of power is this? Does the inverter produce a pure sine wave or is this a modified sine?

Thanks!

[inetdog]

I would hope that SMA would not output a Modified Square Wave (my preference over Modified Sine Wave as a description) without disclosing that prominently in the documentation. But it may be composed of multiple steps rather than being a smooth sine.
Has anyone looked at it on a scope.

[jflorey2]

My question is what kind of power is this? Does the inverter produce a pure sine wave or is this a modified sine?

Pretty much has to be pure sine. Grid tie inverters have strict limits on the amount of harmonic energy allowed in the power they export, which means they must export current in a pure sine wave. No reason to have a second system to generate a square wave when off-grid.

[solarix]

Its good quality sinewave, but there is no surge capability. 2000w and that is it. Drops out the instant you go over 2000w - but comes back when the load decreases. Pretty wonderful feature - built in emergency mode that doesn't need batteries. The only way to get some some off-grid capability without spending thousands.

[SunEagle]

Its good quality sinewave, but there is no surge capability. 2000w and that is it. Drops out the instant you go over 2000w - but comes back when the load decreases. Pretty wonderful feature - built in emergency mode that doesn't need batteries. The only way to get some some off-grid capability without spending thousands.

So my question is how often does the grid go down in your location when you have a very sunny day to produce power?

For my location, power outages are usually during bad weather or at night. That is why the SMA secure power option would not be something I could really use although other people and locations may get more out of it.

[adoublee]

So my question is how often does the grid go down in your location when you have a very sunny day to produce power?

For my location, power outages are usually during bad weather or at night. That is why the SMA secure power option would not be something I could really use although other people and locations may get more out of it.

I think the better question is what would access to that daytime power be worth to a person if the grid was down for a more extended period of time than associated with bad weather outages.

[ButchDeal]

I think the better question is what would access to that daytime power be worth to a person if the grid was down for a more extended period of time than associated with bad weather outages.

pretty little considering its limitations, and the ease of getting a small 12V inverter on a car.

[SunEagle]

I think the better question is what would access to that daytime power be worth to a person if the grid was down for a more extended period of time than associated with bad weather outages.

Ok. I think I understand the mind set of someone that has had long power outages and still wants to get something out of their pv system.

But I still agree with Butch that there are other cheaper ways to generate 2000 watts for short periods of time with or without sunlight.

[solarix]

Here in the sunny southwest, the grid is most likely to go out during a hot summer day when the region gets overloaded with A/C.

[SunEagle]

Here in the sunny southwest, the grid is most likely to go out during a hot summer day when the region gets overloaded with A/C.

Sounds like a distribution problem to me. But I can understand everyone has different issues with their grid depending on where they live and who provides their power.

[adoublee]

But I still agree with Butch that there are other cheaper ways to generate 2000 watts for short periods of time with or without sunlight.

That whole idea of an ICE vehicle being a generator for a long term outage is pretty weak for preparedness IMO. One would have to store extra gasoline, open the garage door to exhaust fumes (possibly freezing contents of garage and further cooling the home in a deep winter outage) or keep the running vehicle outside, run extension cables through the garage/house door, etc. Doesn't count as a solution to me.

Buying a generator is cheaper than buying a PV system, buy not cheaper than selecting a PV system with SPS outlet if it was going to be bought anyway. Additionally, fuel issues still apply and everyone will know you are running a genset even if it is paired with a battery for reduced run times. If some battery is needed overnight it could still be charged from the SPS outlet during the day. Food could be kept cold and a furnace fan could be powered (not all at once).

You don't have to agree with the mentality that it could happen, but SPS if already installing a PV system is a much better solution for extended outages than being given credit for.

[jflorey2]

I think the better question is what would access to that daytime power be worth to a person if the grid was down for a more extended period of time than associated with bad weather outages.

I can think of a few friends who would have been able to save the contents of their basements and freezers with such a feature in the weeks after Sandy.

[ButchDeal]

That whole idea of an ICE vehicle being a generator for a long term outage is pretty weak for preparedness IMO. One would have to store extra gasoline, open the garage door to exhaust fumes (possibly freezing contents of garage and further cooling the home in a deep winter outage) or keep the running vehicle outside, run extension cables through the garage/house door, etc. Doesn't count as a solution to me.

The whole idea of a SPS doing anything for a long term outage is pretty weak for preparedness.
One would have to clean off the solar array and hope for sun shine in a deep winter outage, store power for night time use.
You would have to run extension cables throughout the house door open from the SPS
Doesn't count as a solution for much of anything.

You don't have to agree with the mentality that it could happen, but SPS if already installing a PV system is a much better solution for extended outages than being given credit for.

It is a toy and a costly one at that. other systems are cheaper.

[ButchDeal]

I can think of a few friends who would have been able to save the contents of their basements and freezers with such a feature in the weeks after Sandy.

If the SPS would have saved their basement then a $100 inverter connected to the car battery would have saved them too.

[littleharbor]

The latest generation of SMA GTI's are surprisingly inexpensive. I don't see where this would be a "costly" choice even if you never use it. Plus you get SMA quality as well.