I am going solar

I cannot imagine any savings or investment strategy that reliably returns 12% apr with no risk. If possible, and your SREC is not affected, pay that loan down. A HELOC is probably the most straightforward loan to get at a much lower APR if you do not have the cash, and it is also tax deductible.

I'm not so sure that your understanding of the 'floor' price is correct.

I think of the money this way:
You generate 1.2 kWh a year from each watt installed.
That 1.2 kWh is worth 1.2 (18 cents + 27.5 cents) = 54.6 cents to you.
The first year, you paid in interest $3.6*0.12 = 43 cents

So you net about 11.6 cents a year from each watt installed. The loan APR is causing your repayment schedule to extend out a long time.

 

Why is EU so cheap...subsidy or actual lower cost?
I do not know if its like CNG cars...much more expensive here due to our standards

 

Interesting details -- thanks.

The question of income tax on the SREC proceeds is definitely one to sort out, and a variable I have not considered. Let's take the extreme case of tax on SREC if you sell it, and no tax if it is rolled into the utility loan. Say your marginal tax rate is 33% combined fed/state:

• Tax on the SREC is 27.5*0.33 = 10 cents a kWh
• Interest on the watt with a utility loan is (2.44/1.2)*0.12 = 24.4 cents a kWh
• Low interest HELOC loan after tax deduction is ~ 2%, so the alternate loan will cost (2.44/1.2)*.02 = 4 cents a kWh

So even in this case, keeping the utility loan costs you 10 cents a kWh generated. If you gave up the utility loan entirely, you would lose 6 cents a kWh of subsidy, but still come out 4 cents a kWh ahead. I'm suggesting that you pay off *most* of the utility loan with a cheaper loan or savings, and keep the higher SREC subsidy.

Lower 'soft' costs, meaning mostly labor, but also things like permitting.

I read that German PV installers put up a residential array in half the time it takes in the US. The installers also work on slimmer margins and make it up with volume.

 

That's not quite correct. A properly designed string will allow one panel to be shaded with only a partial loss of production because bypass diodes in the shaded panel take it out of the circuit. (Partial shading of one or more panels that doesn't cause the bypass diodes to carry the current will indeed reduce the entire string's output.) Yes, microinverters ameliorate the issue of this.

However, microinverters are not as reliable as a string inverter, and do not have a track history. A single microinverter failure (while causing only a proportional reduction in output) requires a roof visit, panel removal to get access to the microinverter. If you have 24 panels and 24 microinverters, that's a lot of failure points and a lot of roof walking over 30 years.

Tomorrow I'm having a 2-string (one facing almost due south, the other facing southeast) 6.6kW system installed. I am concerned that the southeast panels might have a shading problem, but the engineer doesn't think so. I also have some of those panels going on a very high roof, which should be tons of fun to keep clean. :-(

I definitely considered microinverters for the reasons you outlined, but became dismayed at the myriad reports of failures. That makes sense, considering they would be baking at 120F+ here in SoCal during summer. It will be interesting to see how my decision pans out.

I'll report once the electric utility deems the system operational.

 

I thought you said $3.6 per watt before tax credit, thus 3.6*0.65 = $2.34 per watt.

The final loan amount is not important to my point, which is that carrying a 12% apr loan if you do not have to stinks.
In your shoes I would find out if I can take the utility loan, pay off most of it, and keep the higher SREC subsidy. That would be sweet.

I have no wish to argue with you; I would like to see you get a great deal
Your calc that the PV array will be paid off in 4 years does not, IMO, take the loan costs into account; and it assumes you will receive ~ 27 cents a kWh SREC subsidy throughout the loan period.

 

'bout time my brathaw !!! Welcome to the 21st century !! Hurry up and show me some roof shots ~ like so .... 7.1kw's



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[/QUOTE]
... A properly designed string will allow one panel to be shaded with only a partial loss of production because bypass diodes in the shaded panel take it out of the circuit. (Partial shading of one or more panels that doesn't cause the bypass diodes to carry the current will indeed reduce the entire string's output.) Yes, microinverters ameliorate the issue of this.

However, microinverters are not as reliable as a string inverter, and do not have a track history. A single microinverter failure (while causing only a proportional reduction in output) requires a roof visit, panel removal to get access to the microinverter. If you have 24 panels and 24 microinverters, that's a lot of failure points and a lot of roof walking over 30 years.

I definitely considered microinverters for the reasons you outlined, but became dismayed at the myriad reports of failures. That makes sense, considering they would be baking at 120F+ here in SoCal during summer. It will be interesting to see how my decision pans out.

I'll report once the electric utility deems the system operational.[/QUOTE]
This is a screen shot of my home PV system on Feb 13, 2015
as you can see, I'm able to monitor PV production at any given moment.
In the picture, the lower very dark an low number panels, are caked with ice/snow since a few days and providing minimal energy. The others are not suffering major shading and still making great amount of PV energy. You will not have the same result with string systems.
I do not know where your information comes from but Enphase energy had manufactured OVER 5 Millions microinverters until 4 quarter of 2014.
I think it is a proven product.
You paid more overall for the installation, but you surely get a better equipment performance and monitoring.
Now, in you geographical location, heat is an issue with many electronics; it is possible that may be more claims for microinverters out of tolerance due to outdoor temperature than in the NE of the USA.

 

My information comes from discussing microinverters vs. string inverters with my design engineer, and reading reliability reports on various fora. Again, you probably hit it on the head: there's a continent of difference between SoCal and Long Island, with our ambient temps hitting 110F once or twice a year, and daytime temps > 90F for days on end. Of course, microinverters that use thin film capacitors in theory should be more reliable.
But large commercial applications seldom, if ever, use microinverters due to the maintenance nightmare of accessing and removing panels to get to them. Microconverters are targeted at residential users for a reason.

Like the early days of the Prius, there are lots of bogeymen proffered about inverter reliability (in 2003, it was "Prius batteries will need to be replaced in five years and they cost a zillion bucks!"). I guess time will tell. I trust my designer. They would have been happy to sell a microinverter system had they felt it offered any advantages over the dual MPPT, dual string approach. And I would have happily gone that route had a compelling reason been presented.

Can't wait to hit the breaker when I get utility permission to launch!

 

I chose microinverters specifically because of significant tree impairments, with shadows sweeping across the array. Summer day production is bracketed by an early morning tree wall and a mid-afternoon tree wall. Winter production has several individual trees in between, spread over most of the day. Large commercial applications would seldom be placed in such a location.

Permission? What is that?

I had a spare traditional style kWh meter on hand (normally used to sub-meter the water heater). So, as a DIY installer, I just plugged it in, flipped the breaker, and started producing immediately. Called for the electrical inspection before their office opened the next morning (well within the required time window), but holiday and vacation schedules delayed actual inspection about ten days. Then the utility bureaucracy took about ten more days to actually get out and swap in their official production meter. So by not waiting, I was producing about three weeks early, at the peak of the local solar season.

 

....."Can't wait to hit the breaker when I get utility permission to launch! ".....
You meant "Commissioning", I didn't wait for the utility company to officially switch me ON also.
Since the Solar contractor job completion day until "LIPA" showed up, it passed almost 45 days, 45 days that I did produce energy and we did use it under the umbrella of "TESTING".
and the no application and use of microinverters in large and commercial applications it is not because of reliability, it is because total cost.
I'm not trying to establish a war of better or worst technology, only presenting the unknown facts as an established user.
PV solar with microinverters is a breeze to maintain and troubleshoot than conventional MPPT enhancer/bypass devices, microinverters offer a myriad of operation parameters including monitoring and can also be tweaked if necessary from a web browser.
Also and the more important, there is a factor of Installer's preference and there profit margins.

 

GREAT !!!
Depending on the high and pitch of the roof planes, you better plan in advance and get armed with a "snow roof rake".
Removal of accumulated snow over the panels will render a faster and better PV energy back to your house.

 

I basically designed the PV layout and spec's, the solar contractor "Empower Solar" took care of the final Engineering, structural plans, permits, etc; in other words, everything.
LIPA at that moment, has some restrictions, for a residential system to be up to 10KWH plus 10%, commercial up to 50KW.
My PV layout takes advantage of East, South and West exposure to the max; I do not have any more room left for extra PV that will be aesthetically pleasant to the eyes.

 

If I was house hunting, and arrived for a viewing to discover a roof laden with solar panels, not sure what my reaction would be. Mixed, at best. But then, I KNOW I'm a bit of a Luddite.