Solar electric 6.5kw expanded to 12.3kw

[begreen]

Right now the curve looks more like the snake that swallowed the elephant.

 

[jebatty]

Agreed yesterday to add 5.4kw to my PV system. Expect it to be installed and producing by early April. The added kwh should make a big dent in kwh usage in my shop and farm property.

 

[jebatty]

1 MW in 30 days! The Feb 14 - Mar 15 period showed 1,013 kwh of production! Makes the mind twist a bit to realize how cold weather and clear skies, sun still low, can outproduce almost every other month of the year.

 

[begreen]

That's fantastic. Helps a lot to have good southern exposure.

 

[jebatty]

March magic in play. March 15, 2014, was my highest single day of production in 2014, 48 kwh. Yesterday, March 17, 2015, reached 47 kwh for the day. Would not surprise me to see that being the highest single day in 2015. The first 17 days of March have averaged 35 kwh/day.

 

[JP11]

I think I need a couple more warm days. I show one inverter only producing.. and it's making 4kw +

They are only rated at 5. So I SHOULD be making good power when the last of that 4 foot drift is gone off my array.

JP

 

[jebatty]

March 2015 did not disappoint. Feb-Mar 2015 nearly matched the same period in 2014. The footings have been poured and the array mounting posts set for the 5.4kw addition to my system. Within a week I'm looking for the panels to be mounted and the system tested while awaiting utility approval to go on-line.

 

[JP11]

You're off to a better start than I am. Last three months:

Jan 33%
Feb 5%
Mar 37% of PVwatts estimate.

But we had an AWESOME year snowmobiling. I sold the snowcat I restored, and bought another one.

Last few days have been pumping out 75kwh per day.

So you'll be at 12kw? I just looked over incentives for my copilot this week. He's in SC. 30% federal, 25% state credit. Then something like retail plus 4c is what it looked like to me. he's planning on 20kw!

I got impatient. I could have waited a couple more days. I don't think I'll do it again.

 

[jebatty]

Do you have much hydro in Maine? The snow melt should be good for that. California is under major water restrictions due to lack of snow. We had practically no snow this winter either, plus very erratic weather and extremely cloudy Nov-Jan. I'm sure you will look forward to snow-clear panels.

I'm waiting with you for your report of over 100 kwh in a day, which would be a major milestone. My 5.4 addition should allow me to get close to that, but since about a 48 kwh day is the max for the 6.5 I now have, I'll look for about 85 kwh to be the future max.

 

[JP11]

I haven't really done the math.. but I'm just guessing. I'm maxing out the inverters now. 10.1 it's two 5k inverters. They run on max for around 4 hours. I'm guessing that with 3 more hours of sunlight on the way by longest day.... I Think I'll make it.

Google says 22 percent of our power from hydro in Maine. Not sure they'll be able to USE all of this snowpack. I think there will be a lot of floodgates open.

I'm just looking around online now. See there's a pellet boiler with a stirling engine. 5kw output, plus 50k BTU of heat. That would be really cool for the winter days to heat my barn. It never ends.

here's a few days ago. I think there's a tree there to cut on the SW side. You can see the hitch in the late afternoon.

 

[jebatty]

Nice curve! I've notice only once that my micro-inverters were clipping. Although rated at 250w each, they regularly will output into the low 260w range.

A graphic for all of March 2015.

 

[JP11]

is the blue bar average, or PVWatts average?

 

[jebatty]

Blue is PVWatts estimate for month daily average.

 

[JP11]

I'm still monkeying with my data collection. With not a whole year in, the data kind of stinks.

JP

 

[jebatty]

On April 9, 2015, installation of 20 additional 270w panels (5.4kw total) was finished and turned "on." My installer says that I have understated the rating of my prior system at 6.5kw and it should be 6.89kw (26 x 265w panels). I had rated the system at the micro-inverter rating (250w/panel). The 270w panels also are using 250w micro-inverters. Total system now is 12.29kw at the panel rating and 11.5kw at the micro-inverter rating.


And the first full day of production, after a cloudy start with rapid clearing.

 

[JP11]

Nice curve. You're going to have to combine the data on your own? No.. must be same micro inverter company.. because I see 11kwh output there.

Congrats. What happens in MN with your overage? I can't remember.

 

[woodgeek]

since the fraction of time clipped by the inverters is small, the 'harvest' is more likely to correspond to the panel rating times annual resource.

 

[JP11]

Just realized we both have 48 panel systems. Mine are rated at 255. The inverters max out about 5060 each though. Got covered in snow.. AGAIN a few days ago. It's putting out 1kw.. but supposed to be real warm today. I'm traveling this week.. but can check in on the array online.

JP

 

[jebatty]

What happens in MN with your overage? I can't remember.

Currently the overage is a bill credit applied against future bills, with the overage $ paid out on request. A bill has been introduced in the MN legislator which will only allow credit in kwh against future bills, unused credits cancelled at the end of the year, and no compensation paid. Thus, the utility gets the power for free which it resells -- I call that stealing. I will be actively opposing the legislation, and I would be surprised if it passes.

since the fraction of time clipped by the inverters is small, the 'harvest' is more likely to correspond to the panel rating times annual resource.

Exactly what the installer said, and I fully agree.

 

[jebatty]

Just realized we both have 48 panel systems.

Close - I have 46!

 

[JP11]

Do you expect true overages? I'm not sure if I will. I reduced consumption with circulators, and will reduce more over time with changeover to LEDs. I will be adding another central air unit. Worst case.. I put my parents bill into my name, and I can send KWH over to that bill.

 

[jebatty]

The original system produced 9MW the first 12 month period. I expect the addition to produce about 7.75MW. Typical annual usage is 12MW. My system is on the house meter, and I have two other meters. Those meters would more than use up the overagel I don't know yet whether the utility or the law will permit combining meters of a single customer. If, so no issue for me, but I still will oppose the bill.

 

[JP11]

Worth a phone call. I had never seen the 'send the power to another account you have' in writing, but a guy from the power company told me I could do it. I haven't tried yet. I'm about 1 year from potentially having any credits 'expire' and probably it wouldn't even be an issue then. (they always use oldest credits first) I'll wait and see if I have as poor a production next winter as this one. PVWatts said I'd make 800 in the winter months.. and I made NONE.

I would for sure oppose the bill If I were you. There's a proposed very large plant in coastal maine. 9 million dollar investment. They are pushing for long term supply contract and some sort of green credits. Not sure if that will benefit me as an individual producer. I should look into it.

JP

 

[CaptSpiff]

It is amazing how the "laws" differ in each state, and more importantly how they can change with the wind. I really think even "Net Metering" is not a certainty in this crazy rapidly changing solar PV landscape. The fight will definitely be won in the state capitals.

 

[jebatty]

I think I had a bit o' the Irish luck with the sun yesterday. Near perfect day, although the sky seemed hazy and the temps were in the 60's -- 80.94 kwh.