Enphase M250 Specs for off-grid, tips and tricks and results

[J.P.M.]

That's a great idea. Everybody north of Dallas should move below that line. Perhaps we can swap all that land in the US with Mexico.

I once suggested the U.S. buy Baja from Mexico, cover it with PV and use the power to desalinate sea H2O. Results: Drought problems in the SW U.S. become a thing of the past, the desert blooms, and anyplace in the remaining U.S. with lousy winters empties out beaucoup pronto.

[ButchDeal]

Bad press? I wouldn't put too much stock in that article, I spent years in that area, it is so bright you gotta wear shades! South of that line I have been to most USA places, and they are full of sunlight, every day. It may be time to just get serious and move your solar to somewhere it will work. The sun is so hot and so every-day bright the grass is all dead by the end of spring.

mmmm stackable magnasines that would be nice, maybe a $10K PACE loan? 16KW cap sounds about right and with 4 parallel inverters with batteries for the nighttime I think it will last a while too. My favorite battery is: Telcomm batteries! I bet you thought I was gonna say Walmart! http://www.northstarbattery.com/batt...opzv/index.php ooo they are expensive but with a 20 year lifespan and up to 3000Ah wow.

WTFAYTA? What article? I included a live link to an ACTUAL SOLAR INSTALL, with live data you can look at.

All you seem to talk about is fairy tales and magic dust that "might some day exist". Build your off grid battery-less micro PV system, hook it up to pvoutput. We would love to see the results (when you have some).

[lkruper]

Bad press? I wouldn't put too much stock in that article, I spent years in that area, it is so bright you gotta wear shades! South of that line I have been to most USA places, and they are full of sunlight, every day. It may be time to just get serious and move your solar to somewhere it will work. The sun is so hot and so every-day bright the grass is all dead by the end of spring.

mmmm stackable magnasines that would be nice, maybe a $10K PACE loan? 16KW cap sounds about right and with 4 parallel inverters with batteries for the nighttime I think it will last a while too. My favorite battery is: Telcomm batteries! I bet you thought I was gonna say Walmart! http://www.northstarbattery.com/batt...opzv/index.php ooo they are expensive but with a 20 year lifespan and up to 3000Ah wow.

That's a great idea. Everybody north of Dallas should move below that line. Perhaps we can swap all that land in the US with Mexico.

[solarddy]

So you only have a grid tie micro system with no battery and are comparing it to an off grid system with battery and generator...
yes grid tie micros are pretty easy though not as simple as legos, BUT have absolutely no backup capability.

What everyone here (including you) is talking about is a system that you can use RIGHT NOW off grid called AC coupling. It uses a second inverter (like you keep mentioning Magnasine) and batteries to allow ANY (yes including micros) GRID Tie system to work off grid. This is a pretty complex install and the batteries and dual inverter system has a lot of configuration and sizing to get right.

Further you suggestion that everyone move to the desert so they can have more sun and not have to worry about cloudy days in temperate climates in the US seems at best ridiculous. A suggestion of Dallas TX seems just as ludicrous , a quick search of pvoutput shows this site just north of Dallas showing clear weather issues on 10/22- 10/25 http://pvoutput.org/list.jsp?p=0&id=...=29366&v=3&s=1 .

Bad press? I wouldn't put too much stock in that article, I spent years in that area, it is so bright you gotta wear shades! South of that line I have been to most USA places, and they are full of sunlight, every day. It may be time to just get serious and move your solar to somewhere it will work. The sun is so hot and so every-day bright the grass is all dead by the end of spring.

mmmm stackable magnasines that would be nice, maybe a $10K PACE loan? 16KW cap sounds about right and with 4 parallel inverters with batteries for the nighttime I think it will last a while too. My favorite battery is: Telcomm batteries! I bet you thought I was gonna say Walmart! http://www.northstarbattery.com/batt...opzv/index.php ooo they are expensive but with a 20 year lifespan and up to 3000Ah wow.

[ButchDeal]

Gas backup... hmmm I just sold my gas generator 6.5KW that I've owned for over 5 years and never turned on for emergency power once. I'd say it loses to micro-inverter phase lock grid tied solar which keeps my Air Conditioner, refrigerator, computer and all other electrical things running all day, every day. (without batteries) Phase 4 will bring a battery bank as my system grows to include emergency off-grid.

Micro-inverter arrays are snap together, like super simple, anyone who can snap together legos could do it, quit lying saying they are more complex.. if 2 more snap together connections x # of micros is too difficult...

Sam Keninson once said: "I know the cure for hunger in Africa, move the people out of the Desert where there is no food, to where the food is." I agree. So if you are having trouble making your solar system work, I suggest moving to where the sun shines to an amount that makes your solar system actually worth owning, because every day the sun comes out, somewhere. I did. you can too.

So you only have a grid tie micro system with no battery and are comparing it to an off grid system with battery and generator...
yes grid tie micros are pretty easy though not as simple as legos, BUT have absolutely no backup capability.

What everyone here (including you) is talking about is a system that you can use RIGHT NOW off grid called AC coupling. It uses a second inverter (like you keep mentioning Magnasine) and batteries to allow ANY (yes including micros) GRID Tie system to work off grid. This is a pretty complex install and the batteries and dual inverter system has a lot of configuration and sizing to get right.

Further you suggestion that everyone move to the desert so they can have more sun and not have to worry about cloudy days in temperate climates in the US seems at best ridiculous. A suggestion of Dallas TX seems just as ludicrous , a quick search of pvoutput shows this site just north of Dallas showing clear weather issues on 10/22- 10/25 http://pvoutput.org/list.jsp?p=0&id=...=29366&v=3&s=1 .

[lkruper]

Expensive to go off-grid with Micro's, true. String better for residential grid tie, False. The sun not coming out for weeks? Maybe in northern latitudes. However if below/south of Dallas Tx., @ 25' x 40' squared there is enough power ...

Sam Keninson once said: "I know the cure for hunger in Africa, move the people out of the Desert where there is no food, to where the food is." I agree. So if you are having trouble making your solar system work, I suggest moving to where the sun shines to an amount that makes your solar system actually worth owning, because every day the sun comes out, somewhere. I did. you can too.

So then, you are of the opinion that in most of the United States and all of Canada there is a problem with weather interrupting solar gain for extended periods?

Perhaps you should move to a country where the sun never stops shining and address your comments to them

[solarddy]

testing testing can you hear me in the back?

Expensive to go off-grid with Micro's, true. String better for residential grid tie, False. The sun not coming out for weeks? Maybe in northern latitudes. However if below/south of Dallas Tx., @ 25' x 40' squared there is enough power to run over 7KW of micro-inverters, which can have all additional non-used A.C. power dumped to a 240VAC or direct from panel PWM or MPPT battery charge controller. True (SolarEagle), Cloudy conditions cut power by a large margin, True. MPPT charge controllers help this a bit (by 30% online sources), so do large capacitors on the D.C. output side of a solar panel, (40VDC caps "surge 50VDC", coupled "parallel" to the panel output for micros on standard 300 watt solar panel + to positive, - to negative like paralleling batteries) the caps turn on the micros under very limited trickle lighting adding about 300+Kwh/mo more under test conditions from only 5. Micro-inverters help with that by adding many separate points of small scale D.C. to A.C. inversion. A single point of capacitors on a 500-1000VDC bus would be cost prohibitive to say the least.

Maybe you should look into micros boosted with trickle-charged caps, they get full of this thing called voltage, then the micros turn on, then the caps discharge based upon load demand, a lot slower than I thought they would have. I think most of you are ok people, just misinformed on what is best, (electro-spun carbon nano-tube mats vs. Batteries of any type) I'm here to help you understand more complex solar systems that are less limited than you might be used to.

Gas backup... hmmm I just sold my gas generator 6.5KW that I've owned for over 5 years and never turned on for emergency power once. I'd say it loses to micro-inverter phase lock grid tied solar which keeps my Air Conditioner, refrigerator, computer and all other electrical things running all day, every day. (without batteries) Phase 4 will bring a battery bank as my system grows to include emergency off-grid.

When Enphase (or some Chinese company) adds the islanding switch- all bets are off, micro-inverters rule. A completely parallel micro-power grid is much better than a SPOF, and when the micro-inverter manufacturers do it, all others will become obsolete overnight. They would need to site reference to parallel capable grid-tie/offgrid inverters such as the Magnasine for IEEE approval in a US courtroom, using the required cut-off Disconnect switch that cuts off the grid in case of utility grid failure, but allows for remote islanding by user manual request by them pushing the islanding button. I've seen plenty of RV's that have an anti-grid-tie switch installed on Youtube when using Inverter power from batteries remotely and not wanting to back-feed the grid with MSW inverters that are not compatible with IEEE grid-tie standards.

Micro-inverter arrays are snap together, like super simple, anyone who can snap together legos could do it, quit lying saying they are more complex.. if 2 more snap together connections x # of micros is too difficult... I wonder about people that post such things.

Sam Keninson once said: "I know the cure for hunger in Africa, move the people out of the Desert where there is no food, to where the food is." I agree. So if you are having trouble making your solar system work, I suggest moving to where the sun shines to an amount that makes your solar system actually worth owning, because every day the sun comes out, somewhere. I did. you can too.

[SunEagle]

No, using microinverters makes the system more complicated, and more prone to failure. The grid can be faked for any grid-tie inverter equally well, and the rest of the islanded system will look the same. It is much easier to balance the generation with the demand when it is managed through a single point (MPPT controller) than when it is distributed and communication with each device needs to occur. Please see ButchDeal's comments in this thread. With some re-programming it might be possible to make microinverters support islanding at least as well as SolarEdge does, but as they exist right now, they are probably the worst choice for building a hybrid system.

Ok. My mistake and lack of knowledge of a hybrid inverter system.

I would never consider or support installing hardware to "fake" a grid tie so the micro inverters would work in "island mode". I just thought if you install a legal micro inverter "grid tie" system and then choose to expand you could then add a charging system.

My thoughts were that while a micro inverter system is more expensive and has a higher chance of point failure then a string inverter it would be easy to just add the DC charging hybrid hardware, as opposed with the need to first remove the existing string inverter with a new hybrid string inverter.

[inetdog]

... Most people with grid power do not need to go Off-grid capable immediately, it's better to get your feet wet and pay off phases 1-3.

Pay off phases 1-3 so that you can afford to pay more for off grid energy than for grid energy for the life of the system?
Most people (all but a very few) with grid power have no reason to go off grid at current power and battery prices.

[ButchDeal]

No, using microinverters makes the system more complicated, and more prone to failure. The grid can be faked for any grid-tie inverter equally well, and the rest of the islanded system will look the same. It is much easier to balance the generation with the demand when it is managed through a single point (MPPT controller) than when it is distributed and communication with each device needs to occur. Please see ButchDeal's comments in this thread. With some re-programming it might be possible to make microinverters support islanding at least as well as SolarEdge does, but as they exist right now, they are probably the worst choice for building a hybrid system.

Right now the best choice for starting on grid and going to off grid in the future is SolarEdge and specifically the SE7600 inverter which can be upgraded latter to support StorEdge. The second best choice would be a traditional Hybrid system like (mine) the Flexpower1 which can be expanded by adding more CC and more inverters as you grow and be programmed for on or off grid.

Going with a micro system and then adding a hybrid system latter like the Flexpower in order to make the micros work off grid will cost more, and the only control over the micros is on or off. The OutBack inverter will handle this on off but is obviously more stressful on it and the batteries as well as clearly more costly and with the more failure points as the flexpower with CC system.
As for using the micros with a SMALL battery and SMALL inverter, until there is a LOT more control capabilities of the micros than is currently possible that will not work. You will need a hybrid system with batteries sufficient to handle the charging of micro inverter array.

[sensij]

It is a plan that can work and is easier to do using micro inverters then if you started out with a string inverter that is not hybrid capable.

No, using microinverters makes the system more complicated, and more prone to failure. The grid can be faked for any grid-tie inverter equally well, and the rest of the islanded system will look the same. It is much easier to balance the generation with the demand when it is managed through a single point (MPPT controller) than when it is distributed and communication with each device needs to occur. Please see ButchDeal's comments in this thread. With some re-programming it might be possible to make microinverters support islanding at least as well as SolarEdge does, but as they exist right now, they are probably the worst choice for building a hybrid system.

[nomadh]

My understanding was the batteries were there to feed the "fake" grid signal to the micro inverters not to use for the household. Just enough power to run the sine wave generator to kick on the panels that would then recharge that feeder system plus the household. If it was at night or a cloudy day then you would have no power , just like any other grid tie system. Only diff is this one could run during sunny days. So many people seem to think if you cant make it work all the time every time 24/7 for years on end then they don't want it at all. Well on cloudy days I need less refrigeration and no AC. In the winter I'm more likely to worry about firewood that electricity. I am currently scrapping all my micro inverter and power optimizer plans just because of the silly little Sunnyboy offline power feature. Its only 1500 watts and only during sunny days but at least I have some power and get some use of my very expensive solar investment without doubling the cost and giving me tons of maintenance work and costs. If microinverters would do what the op suggests in a low price easy maintenance way I'd love it.

[SunEagle]

[ATTACH]7989[/ATTACH]

No batteries M190 diagram, sleep at night, use less batteries, for the "connected" internet family 300-350Ah battery bank is required for nighttime power needs, I call that phase 4 of a deployment of residential micro-inverters. After the system produces enough peak power as measured to allow for battery storage. Most people with grid power do not need to go Off-grid capable immediately, it's better to get your feet wet and pay off phases 1-3.

I agree with you and understand what you are refering to. There was some confussion concerning your original post but I feel you have cleared it up.

Start with a grid tie system and use the POCO as your "battery". If and when you expand the system to a point that now makes sense to capture the excess energy in a storage system instead of selling back (if that is even allowed) to the POCO. That is a true hybrid system.

It is a plan that can work and is easier to do using micro inverters then if you started out with a string inverter that is not hybrid capable.

[lkruper]

Too many posts about the sun not coming out again like it has for billions of years. Ok in a northern climate you may have to double or even triple your solar array estimate, unless you live in the waaaaay north where darkness lasts for longer... I would say that geothermal or wind would be the best bet in those places for renewable energy sources. Gas is a short term not all year long option that is "easy" compared to solar, now as for the single inverter approach, I can see lots of issues with that, mainly a single point of failure that turns the lights out even if the sun does comes out tomorrow.

Either way the sun'll come out tomorrow, I'd bet my bottom dollar on that.

So that when it does my batteries would charge like they always seem to when the sunlight hits my solar panels.

I have highlighted the part of your comment above which shows you don't understand the problem of lack of sun during long periods of bad weather.

The only way to overcome a lack of solar energy over a few weeks is to store it. Every heard the saying of storing up something for a "rainy day"? Extra panels don't help when the sun don't shine unless you have stored it. So to get past a long bout of clouds, without the stored sun in the form of gasoline **, one would need a larger battery bank. The concept is called "autonomy." ## Have you heard that term before in the context of solar?

However, NOONE has a month's worth of autonomy. Maybe if your only load was charging your iPhone, but for a household with people who need lights, heat, refrigeration, entertainment, hot water and so on, that size of a battery bank will break the bank.

If you don't believe me, then put some meat !! on the bone ### you tossed out when you said all it would take would be to increase solar panels by 2X or 3X.

1) What are the daily *** loads for this scenario?
2) What are the size of your panels?
3) How much battery capacity do you have so that you can last for three weeks of cloudy weather.


Footnotes
=======
** Gasoline could refer to anything that can fuel a generator such as natural gas or propane.
*** A literal 24 hour day, not general like in "my grandfather's day"
## Energy stored in a battery for a rainy day
### Bald assertion with no proof
!! Evidence to back up a claim.

[ButchDeal]

[ATTACH]7989[/ATTACH]

No batteries M190 diagram, sleep at night, use less batteries, for the "connected" internet family 300-350Ah battery bank is required for nighttime power needs, I call that phase 4 of a deployment of residential micro-inverters. After the system produces enough peak power as measured to allow for battery storage. Most people with grid power do not need to go Off-grid capable immediately, it's better to get your feet wet and pay off phases 1-3.

The claim was made that micros some how work OFF GRID without batteries. Further that they would be MORE reliable in such a situation even though that situation would require an AC coupled design making MORE points of failure with an over stressed and complicated design. If the hybrid inverter fails everything is down. Get a nice DC coupled system like say an outback Flexpower 2 and you have redundancy in inverter and CC.