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CougTek

Serial computer killer
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Jan 21, 2002
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Québec, Québec
#46
So, one and a half year later, does the system performs up to your expectations? I'm considering solar panels for our main building (even if we are up North) and I'd like some feedback from you.
 
Joined
Feb 4, 2002
Messages
19,277
Location
Monterey, CA
#49
There isn't time of use, but there are usage tiers. The bottom level is <0.10 cents/kwh (even in the winter I never leave this tier anymore). The top level is >0.50 cents/kwh (previously 80%+ of my consumption was here).

Yes, I use a lot of electricity.
 
Joined
Feb 4, 2002
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Monterey, CA
#51
I ended up getting 35% back though national/state/local subsidies and tax breaks. Even without them the payback is within the life of the panels.
 

jtr1962

Storage? I am Storage!
Joined
Jan 25, 2002
Messages
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Flushing, New York
#52
With the 30% federal tax credit dropping after 2019 I'm seriously looking into doing this next year. I already decided to do it myself. I'm going to put the panels on the detached garage, not the house, because I have no ability or desire to install panels on the house roof. Also, in the medium term I may need a new roof, or I may decide to add a second story. Either scenario would basically mean doing the entire installation all over.

Each half of my garage roof is about 82" x 251". That means 8 of these Panasonic 330 watt panels will fit nicely mounted horizontally in a 2x4 configuration. One side of the roof faces south and is ideal. The other side obviously faces north. Does my decision to use 16 panels, even if half of them will be in a less than optimal direction, make sense? I can tilt them more towards horizontal when I install them to minimize the effects of the north-facing slope. Figures I've seen show I might get 50% or 60% as much power from these panels as the ones facing south. Here is the complete system I'm thinking of buying: http://www.freecleansolar.com/5-2-kW-Solar-Kit-Panasonic-330-SMA-Sunny-Boy-p/p330-5kw-sma.htm

The estimates of an optimized system in my location are about 1.5 kW-hrs per installed watt annually before losses. If the north facing half generates 60% as much as the south facing half my average will be 1.2 kW-hrs per installed watt, or about 6240 kW-hrs annually, before losses, perhaps 5000 kW-hrs annually after losses. Current rates are about $0.30 per kw-hr, so the system will save me about $1500 per year. In the relatively short term, I may save more as I'm hearing rates here may top $0.75/kW-hr within ten years. Our current annual consumption is about 10,000 kW-hrs but with the new fridge and going easy on AC/heat we should be able to drop that by at least 2000 kW-hrs. Our base power use is probably well under 400 kW-hr/month (that's refrigerator, lighting, TVs, PCs, etc.). Heating/cooling are the big ticket items.

Incentives include the following:

30% federal tax credit
25% NYC/NYS tax credit (worthless to us as my mother, who owns the house, has no NYC/NYS tax liability)
5% per year real estate tax abatement for 4 years, for a total of 20%
Not sure about this, but there is a megawatt block incentive which offers $0.40 per installed watt, falling to $0.30 pretty soon.

If I assume the shipping is $500, then my total system cost will be $9000. I know I can get at least half that back in tax credits. If I can get the mgawatt block incentive that's another $2080. So the net cost of my system would be no more than $4500, possibly as low as $2480. Had we had enough NYC/NYS tax liability to get the 25% tax credit, the net system cost could be as low as $170. In any case the most it will cost is $4500. That makes the payback period 3 years or less, depending upon how the system performs.

Some questions:

1) I'm planning to mount the inverter in the garage to minimize wiring losses. I figure you'll have fewer losses running 5 kW at 240VAC versus the same power at ~60VDC. Code says the wire will need to be in a conduit. No problem, I've done conduits before. Would a garage-mounted inverter be a problem? The garage isn't climate controlled, but in this part of the country that will generally mean it's cooler than the house for 7 or 8 months of the year.

2) Anyone know about permitting? This might be the biggest problem with a DIY installation, namely navigating the complex maze of regulations. The nice thing is it looks like you get some assistance in that area from these people. They include a custom solar design for free with the purchase of 5kW or greater systems. The only open question is how much will the permits cost? Are we looking at a few hundred dollars, or tens of thousands? The latter wouldn't surprise me for NYC, and it could end up being a showstopper for this. As an example, if a person wants to open up a restaurant here, I've heard there are about 1,000 different permits and forms you need.

3) How do I connect to my electrical system? To me it looks like I would run the conduit with the 240VAC from the garage inverter into the room with the breaker box. After that I just need to connect the two hots and neutral.

4) Will I need a new meter? Do those old magnetic mechanical meters run backwards if you're generating more power than you're using?

5) If the grid goes out can I still have power? I'm assuming I would need to turn off the main breaker so any downed power lines outside aren't live. Or is there something which can do this automatically for me.

6) Am I insane for even considering doing it myself?

No plans for battery backup at this time. The batteries will cost more than the rest of the system.
 
Last edited:

sdbardwick

Storage is cool
Joined
Mar 12, 2004
Messages
553
Location
North San Diego County
#53
I'd get a reputable local company to give you an estimate. They should know the interconnection requirements as well as the details on the tax credits; such as the owner of the house may not be relevant, but rather the owner (purchaser) of the system may be able to claim credits regardless of ownership of the structure. Edit: There might need to be some engineering of the ownership of the system to maximize tax credits/abatements.

If it is a grid-tied system, there will be specific requirements for connection set by the utility, most likely including an auto-cutoff if the grid goes down; no you won't have power if the grid goes down without a LOT of extra work and permits. IIRC, my local utility won't allow connection to the grid without an automatic solar cutoff (at least for residential installs).

Don't know about meters; local utility replaced all spinning disc meters with 'smart' meters a few years ago (so they could fire all the meter readers).
 

jtr1962

Storage? I am Storage!
Joined
Jan 25, 2002
Messages
3,647
Location
Flushing, New York
#54
I'd get a reputable local company to give you an estimate. They should know the interconnection requirements as well as the details on the tax credits; such as the owner of the house may not be relevant, but rather the owner (purchaser) of the system may be able to claim credits regardless of ownership of the structure. Edit: There might need to be some engineering of the ownership of the system to maximize tax credits/abatements.
The credits would be even more worthless to me instead of my mother as my earnings this year are going to be close to zero. Also, there are two problems with having a local company give an estimate:

1) Most charge $1,000 or more for an estimate (non-refundable but they'll credit it towards the system if you decide to let them install it).
2) Very few installers here will install a homeowner owned-system. Most will install the system, and then charge you per kW-hr for the power you use. That mostly defeats the point of having solar in the first place as the rates they charge are only a few cents less than buying power off the grid.

If it is a grid-tied system, there will be specific requirements for connection set by the utility, most likely including an auto-cutoff if the grid goes down; no you won't have power if the grid goes down without a LOT of extra work and permits. IIRC, my local utility won't allow connection to the grid without an automatic solar cutoff (at least for residential installs).
That kind of defeats one reason for having solar, namely at least being able to have power for heat or A/C while the sun is shining even if the grid goes out.

Don't know about meters; local utility replaced all spinning disc meters with 'smart' meters a few years ago (so they could fire all the meter readers).
That's in the cards here, also, but I have no idea of the timeline.
 

sdbardwick

Storage is cool
Joined
Mar 12, 2004
Messages
553
Location
North San Diego County
#55
Wow! Tight market for solar out there.
Here estimates (detailed ones at that) are free, no money due unless you select that firm to do the install. Homeowner-owned systems are common here, but everyone advertises the power purchase agreement (PPA) type as well as $0 down and about half your existing electric bill per month. Or at least they used to...haven't been paying attention since system installed.
Does Costco offer installs in NYC? Their subcontractors out here are viable alternatives; not the best, not the worst (but Costco somewhat standing behind their customers is a not-insignificant lever).
 

jtr1962

Storage? I am Storage!
Joined
Jan 25, 2002
Messages
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Location
Flushing, New York
#56
Costco seems to have a very limited selection of equipment. I have no idea if they'll install equipment you purchase. I've already settled on the Panasonic panels because of the efficiency and lifetime guarantee. In truth, the physical installation isn't the hard part. It's all the legalities and permitting involved. My best alternative might be to find someone who already did their own installation, and see if they're willing to assist me with the paperwork for a relatively small fee. Or I could just slap it up and hope nobody bothers me (although that might make getting the tax credit difficult or impossible).

A few years ago when I was asking around I was getting ridiculous numbers, like $40K for a 8kW system. Even if the tax credits covered half, I figured the payback would have probably exceeded 10 years.
 

jtr1962

Storage? I am Storage!
Joined
Jan 25, 2002
Messages
3,647
Location
Flushing, New York
#57
Sent an email to freecleansolar with my questions:

I'm thinking of using the 5.2kW solar kit installed on my garage roof. The garage is detached. The roof is roughly a 40 degree slope. Each half of the roof is 251" x 82", which means I could fit 8 Panasonic panels on each half in a 2x4 configuration (landscape orientation). One half faces south, which is ideal. The other half faces north.

Some questions:

1) I realize the output will be less for the panels on north facing roof. Can I partially compensate for this by mounting the panels such that they're tilted close to horizontal?
2) Would it make sense to use microinverters instead of string inverter being that the outputs would differ on both halves of the roof? I know you also have a 5.2kW kit with the Panasonic panels and microinverters.
3) My proposed installation would cover virtually the entire garage roof with panels. I've read NYC requires a clear area of 3 feet from the ridge line but is that only for primary dwellings? If not, could I likely get a variance to do what I want?
4) If I did a self-install, would I still qualify for tax credits? Or do I need a professional install?
5) Would your company be able to assist me with all the permitting? This is actually the part I find the most daunting. Physically mounting and connecting the panels is well within my capability but I know nothing about permitting.
 
Joined
Feb 4, 2002
Messages
19,277
Location
Monterey, CA
#58
I did all the research to install myself, picked all the parts, priced it out, etc. It wasn't until I looked into the permits required that I caved and hired an installer. Look into that part before you start buying. One of the permits comes from the local power company, and they were famous for requiring a letter on legal letterhead threatening suit before they would let one be approved.
 

jtr1962

Storage? I am Storage!
Joined
Jan 25, 2002
Messages
3,647
Location
Flushing, New York
#59
I did all the research to install myself, picked all the parts, priced it out, etc. It wasn't until I looked into the permits required that I caved and hired an installer. Look into that part before you start buying. One of the permits comes from the local power company, and they were famous for requiring a letter on legal letterhead threatening suit before they would let one be approved.
That's the part I'm finding the most daunting. ConEd in NYC is actually encouraging solar, so hopefully things here are less onerous. I'm even willing to have someone do the install if the price is reasonable. Freecleansolar would charge $6,500, but maybe I can get that down considering the install is on a low garage roof.

I already got a response to my email:

Thank you for filling out our inquiry form online. The 5 KW Kit Panasonic 330 SMA is 291 sq. ft. using the dimensions you gave me you only have about 284 sq. ft. Can you put some on the house or on a ground mount?

Here are the answer to some questions you had: 1) I realize the output will be less for the panels on north facing. Can I partially compensate for this by mounting the panels such that they're tilted close to horizontal? Not usually worth the effort or expense. 2) Would it make sense to use microinverters instead of string inverter being that the outputs would differ on both halves of the roof? It can produce more power. We can explore that during the design process if you like. I know you also have a 5.2kW kit with the Panasonic panels and microinverters. 3) My proposed installation would cover virtually the entire garage roof with panels. I've read NYC requires a clear area of 3 feet from the ridge line but is that only for primary dwellings? They usually want the 3 feet for safety and maintenance on all buildings. You may be able to get a variance because it is a single story garage. If not, could I likely get a variance to do what I want? 4) If I did a self-install, would I still qualify for tax credits? Or do I need a professional install? Yes you still get all tax credits doing it yourself. 5) Would your company be able to assist me with all the permitting? Yes our permit design service includes everything you need for permitting.

All our kits include our Solar Permit Design Service that supplies you with all the documentation you will need to get your building permit and net-metering application approved with the electric company. During the Solar Design Process we will offer you different options to choose from size of kit, panels, inverters, mounting, batteries, etc. as well as give you the cost per watt, return on investment. and the system payoff for each option. You can start your project with the Solar Permit Design Service which is $449. This credit is applied to the purchase of your kit. Please give me a call to place your order. You can reach me at 888-498-3331 x 7.

Here are some helpful links to get you started...
Read the Solar Buyers Guide for an easy introduction.
Use the Solar Energy Assessment to calculate how much solar you need.
You can always reply to this email or call me to discuss your project. I look forward to talking to you soon. Have a great day.

I wrote back asking if I could get partial or full refund on the $449 solar permit design fee if NYC doesn't grant me a variance to cover the entire garage with solar panels. Unless they do so, the project just isn't viable.
 

DrunkenBastard

Storage is cool
Joined
Jan 21, 2002
Messages
621
Location
on the floor
#60
I don't see how the north facing panels will deliver sufficient output to offset the penalty, if you have a significant roof pitch, which is common in snow regions.

What pitch is your garage roof? Are the exactly north/south facing?

Link below has some numbers depending on your latitude and roof pitch.

https://www.solarpowerworldonline.com/2016/06/much-less-efficient-north-facing-solar-modules/

For running from your panels during a grid outage I believe you need to use an 'islanding' capable inverter. This incorporates a relay/grid tie interconnect that allows it to disconnect the grid from your panel board when it senses a lack of grid power, before power is delivered to the house from the panels.
 

jtr1962

Storage? I am Storage!
Joined
Jan 25, 2002
Messages
3,647
Location
Flushing, New York
#61
I don't see how the north facing panels will deliver sufficient output to offset the penalty, if you have a significant roof pitch, which is common in snow regions.
I thought much the same thing until I read your link (I actually saw that a few weeks ago while researching). Back when solar panels were very expensive it made no sense to have them facing north. Now that they're around $1/watt or less, putting them in less than optimal orientations still results in acceptable payback periods.

What pitch is your garage roof? Are the exactly north/south facing?
Almost exactly N-S facing. The pitch is about 35°, which is nearly perfect for my latitude and higher than the pitch of the house roof.

For running from your panels during a grid outage I believe you need to use an 'islanding' capable inverter. This incorporates a relay/grid tie interconnect that allows it to disconnect the grid from your panel board when it senses a lack of grid power, before power is delivered to the house from the panels.
OK, so it's doable. In truth, we rarely lose power but it would be nice having power during a grid outage. When the price of batteries comes down, I might seriously also consider adding about 10 to 20 kW-hrs of storage.
 
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