Home Solar

CougTek

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#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.
 
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#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.
 
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#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

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#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

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#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

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#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

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#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

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#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

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#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.
 
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#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

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#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

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#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

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#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.
 

Handruin

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#62
I'm having an estimate done tomorrow for installing solar. My roof is almost south facing with minimal to no tree coverage. I'm aiming for 7kWh to 9kWh of solar generation for the house which I hope will cover 100% of my usage.

Have any of you considered single string/central inverters versus micro-inverters when designing your systems? I've read the basic pro/con and was curious what helped make the decision for you.

Also, what are your thoughts on an arbitrage loan for buying into solar? I have a certain amount available to pay for the system which I expect should cover the entire cost. Rather than pay for the entire install out of pocket I was considering taking a solar loan assuming I can get a reasonable rate, and rather invest the same money into an S&P500 index fund which historically has a ~7% avg return (including inflation) over a long term (7-10 years) until I've reached my ROI on the panel install. The payments I normally make toward my energy costs would just move to paying the loan during this time.
 

jtr1962

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#63
I'm having an estimate done tomorrow for installing solar. My roof is almost south facing with minimal to no tree coverage. I'm aiming for 7kWh to 9kWh of solar generation for the house which I hope will cover 100% of my usage.
A 6 or 7 kW system should probably cover that in your part of the country. Covering your needs is ideal but anyone know about the situation where you generate more power than you use? Does the power company buy that power from you at the going rate they charge you, or can the best you do with solar is to zero out your bill? I've just been wondering because at the $0.25/kW-hr total delivery and supply charges if I can sell excess power at that rate I can make a little side income.

Have any of you considered single string/central inverters versus micro-inverters when designing your systems? I've read the basic pro/con and was curious what helped make the decision for you.
I think the key here is whether or not the additional cost of the microinverters is recouped over the life of the panels in terms of more usable power generation. Also, with microinverters you can install a smaller system for any given amount of generation capacity. Then there's redundancy. If one panel or inverter goes bad you still have the remaining panels. If a central inverter goes bad you're SOL. If a panel goes bad you'll lose any panels in series with it until that panel is replaced.

Also, what are your thoughts on an arbitrage loan for buying into solar? I have a certain amount available to pay for the system which I expect should cover the entire cost. Rather than pay for the entire install out of pocket I was considering taking a solar loan assuming I can get a reasonable rate, and rather invest the same money into an S&P500 index fund which historically has a ~7% avg return (including inflation) over a long term (7-10 years) until I've reached my ROI on the panel install. The payments I normally make toward my energy costs would just move to paying the loan during this time.
The amount you'll make doing this is minimal. Say you get a loan for 3% and make 7%. A system of the size you're looking at might be $15K installed but remember the average amount subject to interest over the life of the loan will only be half the borrowed amount. So over 10 years you'll pay 10 * 0.03 * $7,500 = $2,250 in interest. If the $15K you invested really makes 7% then you'll be ahead by $10,500 - $2,250 = $8,250 but that's a big if. My returns in the market have been mostly flat for the last few years. You could even lose big if the market crashes. Just putting the money into the solar system gives you a guaranteed return in the long run. I wouldn't do it with a loan if you have the cash handy.

Question if anyone knows the answer:

This is the last year of the 30% federal solar tax credit. Next year it's going down to 25%. NYS has a credit of 25%. There's also a megawatt block incentive which would be about $1,000 and change for a system of the size I'm anticipating. The problem is the federal and NYS tax credits aren't refundable. They can only be used to offset tax liability. My mother, who would be getting the credits, has no NYS tax liability and very little federal tax liability (i.e. not enough to get the credit over the three years you're allowed). I have no tax liability at all, so buying the system under my name makes even less sense. Can these solar companies use the credits themselves, and just reduce the amount they charge you by whatever the credit is? That's the only way doing this is going to make any sense for me since the only credit of value to me otherwise is the megawatt block incentive.
 

Handruin

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#64
A 6 or 7 kW system should probably cover that in your part of the country. Covering your needs is ideal but anyone know about the situation where you generate more power than you use? Does the power company buy that power from you at the going rate they charge you, or can the best you do with solar is to zero out your bill? I've just been wondering because at the $0.25/kW-hr total delivery and supply charges if I can sell excess power at that rate I can make a little side income.
If I install a PV system (or any system for that matter) that is "Class I customers: 60 kW or less" and I drive the electric meter backwards in a surplus, my local utility company (Eversource in Massachusetts) pays me the same rate back at 100% of retail rate.
Class I customers receive 100% of the value of their excess kilowatt-hours, including Eversource charges for basic service, distribution, transmission, and transition.
The small downside to a power surplus is that Eversource will not pay me directly for the generation, I earn credits toward future power purchase. There are ways in which I can transfer my credits to others in the same region who are Eversource customers and find a way for them to pay me for the power.

In addition to offset or surplus, there is also a payment system called a SMART metering that Eversource will have to pay me a fixed rate irrespective of the amount I consume; it's based on pure generation of power. I'm still trying to figure out the details but it appears to be capped and I have to apply for it as an incentive. The contractor said it's 80% of current rates so somewhere in the $0.145/kWh that I will get paid directly.
http://masmartsolar.com/
https://www.solarreviews.com/blog/h...am-in-massachusetts-change-solar-payback-time

There is also the federal credit of 30% of the cost of the installed system is given as a tax rebate that you already mentioned.

I think the key here is whether or not the additional cost of the microinverters is recouped over the life of the panels in terms of more usable power generation. Also, with microinverters you can install a smaller system for any given amount of generation capacity. Then there's redundancy. If one panel or inverter goes bad you still have the remaining panels. If a central inverter goes bad you're SOL. If a panel goes bad you'll lose any panels in series with it until that panel is replaced.
After having a nice conversation with the contractor, they only use panels with micro-inverters in my area. He said this was part of an initiative from the local fire departments because it was safer for them to deal with AC power being sent from the roof of the house versus DC to a string inverter. This contractor uses Enphase solar panels for their clients and projects and they have a software suite called Enphase Enlighten for managing the data from each panel and inverter.

The amount you'll make doing this is minimal. Say you get a loan for 3% and make 7%. A system of the size you're looking at might be $15K installed but remember the average amount subject to interest over the life of the loan will only be half the borrowed amount. So over 10 years you'll pay 10 * 0.03 * $7,500 = $2,250 in interest. If the $15K you invested really makes 7% then you'll be ahead by $10,500 - $2,250 = $8,250 but that's a big if. My returns in the market have been mostly flat for the last few years. You could even lose big if the market crashes. Just putting the money into the solar system gives you a guaranteed return in the long run. I wouldn't do it with a loan if you have the cash handy.
Why would only half the loan be subject to interest over the life of the loan? I would have expected something like:
$15K loan over 10 years at 3%
Total interest paid: $2,380.93

If I used the S&P500 to estimate from past returns of 2009->2019 (which I realize is no guarantee) and did the same $15K over ten years that would be worth ~$53K or $48K after 15% tax rate.

Question if anyone knows the answer:

This is the last year of the 30% federal solar tax credit. Next year it's going down to 25%. NYS has a credit of 25%. There's also a megawatt block incentive which would be about $1,000 and change for a system of the size I'm anticipating. The problem is the federal and NYS tax credits aren't refundable. They can only be used to offset tax liability. My mother, who would be getting the credits, has no NYS tax liability and very little federal tax liability (i.e. not enough to get the credit over the three years you're allowed). I have no tax liability at all, so buying the system under my name makes even less sense. Can these solar companies use the credits themselves, and just reduce the amount they charge you by whatever the credit is? That's the only way doing this is going to make any sense for me since the only credit of value to me otherwise is the megawatt block incentive.
 

jtr1962

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#65
If I install a PV system (or any system for that matter) that is "Class I customers: 60 kW or less" and I drive the electric meter backwards in a surplus, my local utility company (Eversource in Massachusetts) pays me the same rate back at 100% of retail rate.

The small downside to a power surplus is that Eversource will not pay me directly for the generation, I earn credits toward future power purchase. There are ways in which I can transfer my credits to others in the same region who are Eversource customers and find a way for them to pay me for the power.

In addition to offset or surplus, there is also a payment system called a SMART metering that Eversource will have to pay me a fixed rate irrespective of the amount I consume; it's based on pure generation of power. I'm still trying to figure out the details but it appears to be capped and I have to apply for it as an incentive. The contractor said it's 80% of current rates so somewhere in the $0.145/kWh that I will get paid directly.
http://masmartsolar.com/
https://www.solarreviews.com/blog/h...am-in-massachusetts-change-solar-payback-time

There is also the federal credit of 30% of the cost of the installed system is given as a tax rebate that you already mentioned.
I'll need to check if ConEd does something similar, although the way I'm sizing my system it probably wouldn't generate a net surplus beyond my annual average usage.

After having a nice conversation with the contractor, they only use panels with micro-inverters in my area. He said this was part of an initiative from the local fire departments because it was safer for them to deal with AC power being sent from the roof of the house versus DC to a string inverter. This contractor uses Enphase solar panels for their clients and projects and they have a software suite called Enphase Enlighten for managing the data from each panel and inverter.
That makes sense from the perspective you mentioned, plus micro-inverters already have all the other advantages I mentioned.

Why would only half the loan be subject to interest over the life of the loan? I would have expected something like:
$15K loan over 10 years at 3%
Total interest paid: $2,380.93
The average balance subject to interest over the life of the loan would be about half the principle. When you're first starting payments, the balance is $15K. When you're almost finished, the balance is close to zero. Your total interest paid figure agrees pretty closely with mine.

If I used the S&P500 to estimate from past returns of 2009->2019 (which I realize is no guarantee) and did the same $15K over ten years that would be worth ~$53K or $48K after 15% tax rate.
Using that period is an anomaly. Remember the market crashed in 2008. Usually market gains are in the area of 40% or 50% in the first year of recovery from a crash. The long term average is 7% to 8%. Compounded over 10 years that would mean a total return of close to 100% if we assume 7%. In other words, your $15K would be worth about 30K. However, lots of people I've talked to are telling me the markets have been in a bubble, and have been propped up by federal policy since 2008. It's likely we're going to see negative returns for a very long time once the first big correction happens. I'm getting out of the markets within the next few months, and putting everything in cash or cash equivalents.

On the flip side, if you can find something relatively safe to put that $15K into which offers greater returns than the loan interest go for it. I'm thinking bond funds which might pay 4% or 5%. Some solar installers offer near zero interest loans, so your idea could still work.

Another option if you know anyone with spare cash in the bank is to borrow from them. Right now banks are only giving something like 0.1% on savings accounts. A person might be happy to loan you money at, say, 2%, as it's better than what they're getting. If you do that, make sure it's official with signed promissory notes and so forth. If you can borrow at 2%, and invest in something safe at 5%, you can still come out ahead.
 

Handruin

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#66
I got my quote back for the solar system. They ended up proposing the use of LG Neon R 365watt panels with a power optimizer inverter from SolarEdge. The system is spec'ed to be 27 panels with a total generation size of 9.855 kW with estimated annual production of 9,213 kWh. This company claims to be 10% conservative in their estimates to help manage expectations.

Their installed quote is $31,500 before any rebates or incentives. There is a $1000 state tax credit and $9450 federal 30% tax credit. Estimated years to break even is 5.6 when I include the SMART metering payments over those years. The math suggests the completely installed system would be at $3.19/watt for solar generation before any incentives. As of June this year, the average in Massachusetts is around $3.67/watt for a system around 10kW.
 

jtr1962

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Flushing, New York
#67
The price sounds in line with what other places charge. One thing everyone should do before installing solar is see where usage can be reduced. We went from an average of around 1000 kW-hr/month to 670 and dropping (I'll know the exact figure as soon as the cooling season is over). How did we do it? We got a new fridge about 18 months ago. We needed it anyway, but it uses about half the energy of the 40 year old model it replaced. Then we started using heating pads on the beds instead of electric heaters. That produced big savings. Since the circulator pumps and oil boiler use power, turning down the central heat saves on oil as well as electricity. With my mom being 80 there are limits to that, but when she's gone I'll probably shut the central heat off altogether and just use a space heater in whatever room I'm in. Long term though we're probably going with zoned geothermal heating and hot water. Oil just costs too much, plus residential oil heating won't be allowed in NYC after either 2025 or 2030. So the boiler has to go regardless. Geothermal makes the most sense of all the options. Our electric bill in the winter will certainly go up, but that will be more than offset by the $4K we'll save on oil. And zoned heating will let us just heat the rooms we're in, not the entire house. Next thing we did was unplug any devices which we rarely used but which had parasitic power drain. Finally, we're a lot more careful with A/C use in the summer. That decreases the average summer use from ~1500 kW-hr/month to somewhere under 1000.

The bottom line is the lower your average power use, the smaller the solar system you need. Unfortunately, you're further north than us, so your system will generate less for any given size. Nothing you can do about that.
 

Handruin

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#69
I ended up singing on with the contractor. The LG 365W panels just became end of life so now I'm getting the newer ones that are 370W. My system will be 28 x 370W panels for 10,360W with SolarEdge power optimizers and a SolarEdge inverter with a 25 year warranty on both. They're doing the paperwork and planning with my town for permits as well as establishing the connection with my energy provider. I should have the system installed mid August. I hope this works out as a basic investment; time will tell.
 

DrunkenBastard

Storage is cool
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#70
My only advice would be to make sure the specified inverter is capable of islanding (allowing you to run off the panels if your utility power goes down). This function will disconnect from the grid when its down so there's no risk to line workers from your solar generation. Otherwise you won't be able to use them when you potentially need them the most.
 

snowhiker

Storage Freak Apprentice
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1,503
#71
My only advice would be to make sure the specified inverter is capable of islanding (allowing you to run off the panels if your utility power goes down). This function will disconnect from the grid when its down so there's no risk to line workers from your solar generation. Otherwise you won't be able to use them when you potentially need them the most.
I'm guessing that 99% of the people with solar believe they'll be sitting pretty when the next blackout comes. Of course not realizing that during a grid-down situation their solar will shut off.
 

Handruin

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#72
My only advice would be to make sure the specified inverter is capable of islanding (allowing you to run off the panels if your utility power goes down). This function will disconnect from the grid when its down so there's no risk to line workers from your solar generation. Otherwise you won't be able to use them when you potentially need them the most.
Unless I haven't found the right info, my understanding is without a decent bank of batteries in an AC-coupled config, running a house purely off PV panels is not a good idea during a grid-outage. Having a battery setup to regulate the islanded PV power generation is the safest way so that my electronics are not damaged if they draw more power than the panel inverters can deliver when there is an immediate demand, say like when an AC compressor kicks on or something. I realize there are a few devices to give a limited amount of power (1500-3000W) during grid-outages but to do this right and have a hybrid grid-tied system that also works when the power is off works best when you have batteries to regulate the voltage via a grid-tied battery backup config. I'm not looking to spend money on a battery backup system. Maybe down the road I will consider something like this and I can make the necessary changes to implement that feature.

If you know of a power optimizer inverter that can run perfect without batteries when the grid is down please let me know and I'll read up on it. I'm just not aware of one except for the devices I mentioned earlier that will give limited amounts of power for emergency devices in the range of 1500W-3000W.

I'm guessing that 99% of the people with solar believe they'll be sitting pretty when the next blackout comes. Of course not realizing that during a grid-down situation their solar will shut off.
I must be in the 1% of people that does not expect my house to have power when the grid is down even though I'll have PV panels.
 

jtr1962

Storage? I am Storage!
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Jan 25, 2002
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Flushing, New York
#73
Honestly, when I was researching solar panels it was kind of a shock to me that by default you won't have power if the grid was down. One of the reasons, albeit a minor one, for getting solar panels is exactly so you have power during blackouts. The fix is relatively simple, namely to have a relay which disconnects the house power from the grid if the grid is down.

I'm aware batteries work best to buffer loads but even without them things should work fine unless you have loads which give very heavy surges when turning on, like central air. Batteries are great to have in a solar system, but when I priced them out they cost as much as the panels and installation combined if you want to have enough battery back up to ride through a few cloudy days.
 

Clocker

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#74
Howdy Doug- IIRC you live out East and get a fair amount of snow. I'm in Michigan and I have a couple large portions of my roof facing directly south. How much efficiency is lost to snow covering the panels? I am kind of interested in looking at solar but assumed it would not be cost effective since the roof has snow cover for a good portion of the year. Also, if your system is roof installed, I'm wondering how the cost of removing and reinstalling the system is handled when it's time to replace the roof and how that cost is factored into the overall savings?
 

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Stereodude

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#75
Howdy Doug- IIRC you live out East and get a fair amount of snow. I'm in Michigan and I have a couple large portions of my roof facing directly south. How much efficiency is lost to snow covering the panels? I am kind of interested in looking at solar but assumed it would not be cost effective since the roof has snow cover for a good portion of the year. Also, if your system is roof installed, I'm wondering how the cost of removing and reinstalling the system is handled when it's time to replace the roof and how that cost is factored into the overall savings?
If a panel is covered you don't get any power. If part of it is shaded you may not get any power depending on what part is shaded. If you have multiple panels in series, one of the panels in shade will cause problems getting much power as well.
 

Handruin

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#76
Howdy Doug- IIRC you live out East and get a fair amount of snow. I'm in Michigan and I have a couple large portions of my roof facing directly south. How much efficiency is lost to snow covering the panels? I am kind of interested in looking at solar but assumed it would not be cost effective since the roof has snow cover for a good portion of the year. Also, if your system is roof installed, I'm wondering how the cost of removing and reinstalling the system is handled when it's time to replace the roof and how that cost is factored into the overall savings?
Hey Kevin, Yeah I'm out east in Massachusetts and we can get decent snow but it's not that bad. Depending on where you are in Michigan you're more North than I am. My understanding is that snow isn't really the issue when it comes to losing efficiency, it's the fact that the sun is so low on the horizon during winter months that the panels won't be generating nearly as much as during the peak times of year. I guess it depends on the number of months you get snowfall.

The info I've read and videos I've watched show that you really don't need to worry about pulling snow off the panels during the winter months but you can use a roof rake if you wanted to. It may be worth you having someone come out and do a solar study where they can forecast the amount of solar hours you get throughout the year in your area. Then they can draw up some numbers so that you can figure out the length of time to get a return on your investment. You can also get a rough estimate from Google's sunroof page to show the amount of sun your roof will get.
https://www.google.com/get/sunroof

I don't have a clear estimate on the cost to remove the panels for when it becomes time to replace the roof. I was told that the panels will help extend the life of that area they cover. Most companies will try to get you to estimate the age of your roof and encourage to replace it before putting panels on it if it's older than 15-20 years. I don't know the age of my roof so I estimated it to be about 10y/o which is isn't really worth replacing. I also know I've never lived in a single place for more than 8 years so I'm not really worrying about it right now.
 

Handruin

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#77
If a panel is covered you don't get any power. If part of it is shaded you may not get any power depending on what part is shaded. If you have multiple panels in series, one of the panels in shade will cause problems getting much power as well.
The last part only applies if you install the old style string inverter where they are all wired in series. Using power optimizers or micro inverters will alleviate the drawback of one or more panels affecting the entire array. All the contractors I spoke with in my area will not install a string inverter and longer.
 

DrunkenBastard

Storage is cool
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#78
Unless I haven't found the right info, my understanding is without a decent bank of batteries in an AC-coupled config, running a house purely off PV panels is not a good idea during a grid-outage. Having a battery setup to regulate the islanded PV power generation is the safest way so that my electronics are not damaged if they draw more power than the panel inverters can deliver when there is an immediate demand, say like when an AC compressor kicks on or something. I realize there are a few devices to give a limited amount of power (1500-3000W) during grid-outages but to do this right and have a hybrid grid-tied system that also works when the power is off works best when you have batteries to regulate the voltage via a grid-tied battery backup config. I'm not looking to spend money on a battery backup system. Maybe down the road I will consider something like this and I can make the necessary changes to implement that feature.

If you know of a power optimizer inverter that can run perfect without batteries when the grid is down please let me know and I'll read up on it. I'm just not aware of one except for the devices I mentioned earlier that will give limited amounts of power for emergency devices in the range of 1500W-3000W.



I must be in the 1% of people that does not expect my house to have power when the grid is down even though I'll have PV panels.
Given you may get batteries in the future what I'm suggesting is make sure the inverter you get now is capable of islanding, as opposed to having to replace it down the track unnecessarily. All my sensitive electronics are on smaller UPS units, but I wouldn't hesitate to run while grid is down without house batteries if I did have solar. With 10kw of panels you'll prob be good for about 8kw in full sun? Not sure how sophisticated the setup will be but seems like you could set the ac breaker to load shed first and leave the critical house loads up? Or leave the AC unit without backup power - as it seems a waste to use battery power to power a high demand load like that.
 

Handruin

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#79
When I say I may get a battery system the future, it may be more like 10-12 years. My budget for this project only has room to pay for the solar panel system install. The expected lifespan of my inverter is probably around 10-12 years, so when it comes time to replace I can revisit then if I still have an interest in batteries and off-grid support.

I agree that it would make sense to put the mission critical components into their own breaker that would run off-grid and not use the A/C. This would be another expense to have an electrician come in and put in a second panel to move all the breakers I need into it. I guess what it is coming down to is that off-grid support wasn't really in my plan or budget for this project. I really just wanted to offset my energy costs and get to a break-even ROI in about 5 years.
 

Handruin

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#80
Today is raining and very overcast. Barely able to push out anything.

Screen Shot 2019-09-12 at 10.17.05 AM.png

Yesterday's was much better for production even with partly cloudy conditions.
Screen Shot 2019-09-12 at 10.16.01 AM.png
 
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