DIY solar array 12.5 kw

[gasstingy]

982 kWh in May. 6.81kW Array. Arab, AL

[pinballlooking]

Originally Posted by gasstingy

982 kWh in May. 6.81kW Array. Arab, AL

Nice so you were over your estimated power output also.
Was that one of your best months?

[gasstingy]

I have only ever done an estimate based on the yearly average. My yearly average estimate is 10,508 and I haven't hit it yet. I haven't adjusted it either.

Year one, we made 9,176 kWh. I'd had a faulty connector on the big array that took out 1/2 of the array from 4/30 until 5/15. {Solar guru fixed it at no charge, but I was still out the production amount.} I was pretty sure the array was under expectations during that time period but had yet to figure out how to check it, except to see what it's maximum output was on a sun shiny day.

Year two, last year, we made 10,441 kWh for the year. We had no real defects to point to, so.... maybe I have too high an expectation, I don't know.

FWIW, I also have a spreadsheet to let me know where I stand on getting my investment back. It helps when somebody asks what the payback time is on it. As of today, I am 46.505% paid back. 30% of that was Federal Tax Credit {expires EOY 2016} and the other was basically production credit. TVA has an annual rate increase, usually 1.5% that will alter it a bit, but I'm on course to be repaid for my initial investment in 10.5 years, excluding any rate increases since last years increase.

So, May 2013 was 750 kWh, last May and this May were both the exact same 942 kWh. Strange but true, I read the meter everyday. Something about generating my own electricity makes me feel good at the very core of my being.

[pinballlooking]

What you are describing is exactly why I bought a product with per module monitoring. It is too hard to detect when you are having issues without it.


As you may already know. PV watts will give you a pretty good month to month est.

Just plug your numbers in.


I don’t think checking every day is bad I have TED monitoring and I leave it up on my computer all day every day.
http://www.powermeterstore.com/P7774/ted_5000.php

I can bring it up on my surface and android tablets and our phones. I even monitor it while I am away from home.

[gasstingy]

Thanks for the link to PV Watts. I just left it on Huntsville since I'm so close and it says May should be good for 810 kWh. COOL, I'm 16% over expectations for May, 7% over for YTD. Back to that warm fuzzy feeling!

I don't have internet at home and don't have any need to get it, yet. What I can say is that I have 1 Enphase inverter that is offline AGAIN. I am far more pleased with my Sunny Boy, especially after I figured out how to read the data log part that gives me module level performance.

I'll get to the Enphase micro inverter soon enough. Since they went to a Chinese manufactured inverter, I've not been as impressed with them as I am with the original American made inverters. They say they can do over the internet fixes for some events on both the first and second generation inverters, but it doesn't make up the expense of paying for internet to wifi it to.

[pinballlooking]

Our system have been running 26 months and we just hit the 40 MWh mark.
Since our power cost about .10 Kwh that is $4,000 Solar power made.
We are very pleased with the system performance. We are now able to cover all our power usage and this also covered driving our Chevy Volt 38,484 EV miles.

Hot water is the only thing we have on natural gas. Everything else runs on solar. Our water bill is higher than our power bill and natural gas bill combined. Power bill and natural gas bill combined is under $30 a month.
Last month gas and power bill together was $26.25 my water only bill $40.25.
We have septic tank so this is for water only.


The bottom array was added later that is why those numbers are lower.

[pinballlooking]

We were so close to having back to back 2MW months.
We had a storm today that made us miss the 2MW mark. We ended up with 1,994KWh.
In the last two months we made over $400 worth of power that is still pretty good.

We are carrying over 2/3 the power we will need this winter to heat with and drive our Volt.
We have 2009KWh carryover now and we need about 3MW carry over for the winter.



Others with solar tell us your number when you have them.

[Robaroni]

PB,
We've had a really rainy month but I just checked and we still did OK. Here's the intertie stats for the last few years, with the off grid/intertie system added to this we did a little over a Meg in June but our house is running during the day on the second system and selling the excess back so it's pretty good overall.

Rob

[stevehull]

PV guys - got a couple questions. I am just itching to get my self install 15 kW system up, but am doing my homework, carefully.

Will go with Enphase - for a lot of reasons not relevant here. That said, I can put in poly panels (250 watt) with M215s for a 15 kW system for a LOT less than a mono system. The poly system (lower wattage panels) requires more panels for 15 kW, so additional racking, wiring and inverter costs are in there. Even with fewer panels/racking/wiring, the mono system (M250 and 300 watt mono panels) is ~ 15% more for an equivalent size kW system. All else is the same (wiring to box, etc). The prices were checked on a variety of sites (Renvu, Wholesalesolar, etc). I have plenty of roof room for the additional poly panels, so space is not the issue.

I know about the Enphase C250 that has 72 cell compatibility, but that is three phase.

1'st question. Just go with cheapest 15 kW system, in this case poly?

Second issue. 300+ watt 72 cell panels are becoming the norm (vs 60 cell). I have heard that Enphase has a higher wattage, higher cell microinverter in the works ("M300"?). The M250 simply can't take the higher voltages that the 72 cell 300+ watt panels put out.

Question 2 Even though I can't stand it, is it worth it to wait until this newer inverter model is released? This will push down prices for M250 and certainly M215s.

I know that the system MUST be in service and utility accepted by Dec 31, 2016 to get Federal tax credit.

Waiting sucks . . . but better to plan carefully (measure twice, cut once) . . . .

Thanks in advance,


Steve

[pinballlooking]

You are very much like me when I was deciding I have the space or can make more space if needed.

With using good equipment and you are. You should go with cheapest cost per watt installed. Solar is great in all but fast payback trumps everything!
There is no way I would wait for 72 cell panels. Enphase had a product for them in the past and had many issues with that product.

The M215 has proven itself in the field as dependable any new microverter will not have time to prove itself before you will install.

If you find a great deal jump on it keep in mind shipping is very expensive for the big items and combine them as much as you can.

I found that the smaller items is where the make up their margins. I bought most on the smaller items off eBay. They smaller items just push shipping even know it should not.

I got Enphase wire clips off ebay grounding clamps… it all helps faster payback time. I went to the guys I was ordering the big stuff from and said I can get the Envoy off ebay can you match and they did.

Now that you decided to get solar every day you wait is costing you money.
Don’t forget to look at the cost of waiting in your calculations.

Really now you know how much you will save each month so there is a cost to waiting and that cost is more than the small amount you will save by waiting.

I made over $400 worth of power in the last two months you will make more than that. Just missing this summer will be expensive for you.