Solar Power - Self Install or Not?

[networkcameracritic]

With all the electronic gadgets I have besides computers & cameras, I run up a hefty electric bill. I'm thinking of going solar but the bids I'm getting for a 5-6KW setup is sort of high, about $30K for 23 panels (before any federal tax credit). I look at the same equipment they are using and it comes out to $10K for the hardware, about a buck a watt for solar panels, made in USA, and a 7KW inverter runs about $2,500. There's other stuff needed, like hardware to attach the panels to my roof, wiring and a quick disconnect but that's trivial, say a grand for the assorted sundries. Based on what I read, the Federal tax credit of 30% applies to owner installed systems as well as long as they are permitted and the State of California allows owner build, so no contractor license required.

So am I missing something here, like if I hired a roofer to securely mount the brackets and panels to my roof and hired an electrician to do the wiring and attach to the meter, I can't image there's $20K in labor. The panels come with the electronics on the back that plug into each other. Or maybe there's solar installers that I can hire directly that can install a system like this for say $5K which may be reasonable for a crew of 4 for a week.

Any of you have solar and what's been your experience with the installation process?

 

[nayr]

If you have every intention of living out your days in that house you might look into a lease to own type install; one of my co-workers got one installed; cost her pretty much nothing out of pocket, lowered her electric more than her payments for the solar.. The biggest down side is apparently if you go to try to sell the house it is scaring buyers away whom see a lien on the title and freak out; even though for like $20 you can transfer the lease to new owners and IMHO it adds value if your house generates more electricity than it consumes.... iirc she got ~$50k system on her roof on a 15yr lease.

Having said that; I am going to be setting up solar here soon in a DIY fashion.. However my plans are different than most people's, I will not be tying it into the grid.. I intend on setting up a separate standalone power system with a battery bank and size it so I can run all the household nessicities off my own grid.... ie, network/ipcams/security system/lighting/refrigeration and heater blower.. basically the idea being I want a truly uninterruptible power supply for critical infrastructure so I dont need a generator/fuel to make it through a bad natural disaster...

My wife and I are looking at acquiring some northwest vacation property and building a Tiny off the grid cabin on it where we can spend the summers.. I am intending that our only monthly bills on the place be satellite internet for cam viewing when away and working form the cabin when were there... That entire place is going to be ran off DC power; no inverters.. I can convert electronics and appliances from AC/DC easy enough.. just replace the AC power supply with a voltage regulator or replace the AC motor with a DC equivalent and you eliminate the DC <-> AC <-> DC conversion losses since most everything runs off DC internally already.

 

[icerabbit]

I think many of us have a bit of the same issue with toys, power use and electric bills.

Unfortunately I don't have solar experience yet. Would love to do it, but site issues pretty much prevent it (and practically we need a backup generator more), so I've only read about solar from time to time. Supposedly DIY solar could save 1/3 to 1/2 of the cost. Of course need the utility to be in on it, probably a permit & inspection and an electrician for the tie-in.

I think your idea of hiring a roofer and electrician is worth exploring. Supposedly some of this stuff is largely plug and play, when you follow instructions. Maybe you can find a roofer with solar experience? I wouldn't just trust the average roofing team. What if it turns out there's an issue up on the roof? ...

I always thought, if we did solar at any point in time, I'd never have it on a high roof, and instead on a rack on the ground or car port or even a custom fence, so I can install & troubleshoot things myself.

Anyway, looking forward to hearing more about your project & progress.

 

[networkcameracritic]

I've been researching it more and what's new in the his business is micro-inverters that fit under each panel. I think this makes it easier to install as it makes the system AC instead of DC, so less dangerous and no central connection point, single point of failure. So instead of having saying 20 panels attached in series to a single large inverter, you can add panels one at a time, and with the micro-converter, you don't have to size an inverter then replace it years later if you want to add more panels. So far, most of the rough bids I've been getting are in the $5.25 per watt range. DYI I figure would be closer to half that. So looking for something in between.

 

[nayr]

yeah micro inverters are awesome; AC is not less dangerous than DC however.. but it will be cheaper to install because you can run much lower gauge wire and for longer distances; lots of heavy gauge copper wire is a big expense of a DC solar systems.. If going this route i'd make sure the micro-inverters were modular and could be upgraded/maintained without replacing the entire panel.

Its not horribly efficient for storing power in DC battery banks tho because you have to convert the AC back to DC again so there is additional loss; then you need an inverter for the batteries.. if your not using batteries and want your meeter to just slow down or go backwards then this is not an issue.

 

[networkcameracritic]

The micro-inverters convert at the panel level, so if there's a shadow blocking one panel, it does not affect other panels output like it does with a traditional string inverter for the entire system, but mine are in complete sun all the time, so don't need it for that. The downside to micro-inverters is they are new, so long term reliability being outdoors under a panel is unknown. Also, it's a bigger effort to replace as you have to remove the panel to get to each. Will have to see what the cost differential is if it's worth it. Also, warranty is an issue as the micro-inverters that are common do not include labor in the warranty, the big inverters do. Checking around, it's possible to get systems for $3.25/watt, so I'm hunting for a worst case of $4/watt with high efficiency panels and micro-inverters.

As for dangerous, it would be so if you got shocked by DC vs. AC.

 

[nayr]

As for dangerous, it would be so if you got shocked by DC vs. AC.

both carry the same relative current and thats what is dangerous; pulses of high voltages or a steady low voltage are equally as bad to our biology given the same current.. DC tends to make you hold on and burn since its constant; AC shuts down your heart and nervous functions from the alternating pulses a 60KHz.. Edison used to promote DC as being safer than AC and the electric chairs are AC; but truth is neither has an advantage in safety... electricity is dangerous; period.

As they say; its not the voltage that kills yeh.. its the amps.

DC only has 1 hot wire, AC has two.. so your running two much smaller wires vs 1 bigger wire; AC would be easier and cheaper to install.. but both will deliver the same amount of energy from the panels to your devices; just using different encoding methods.

Long term durability of an outdoor micro-inverter will never reach that of a well made indoor "mega-inverter"; if your need low maintenance then the choice is obvious.. if your a DIY installer and can maintain them then whom cares as long as its cheaper in the long run... if it costs $300 just to have someone look at it then you may wait til this matures or find an installer who's warranty covers labor.

 

[Andy]

I've design PV systems for a living, First let me say that 23 is an odd number of panels and would be impossible to string on a single MPPT inverter. Depending on if they are 60, 72 or 96 cell panels microinverters may not be an option. Only Power One now ABB has a High Voltage Micro capable of working with 72 and 96 cell panels.

The wiring for the DC from the end of the string to the DC Combiner which is usually located at the inverter will be in the range of 6 to 10 Amps and several hundred volts so #12 CU is fine.

Be careful thinking that only one DC conductor is live since most modern inverters are TL (transformerless) and both legs of the array float. Only the module frames are grounded.

Micros are actually more expensive than string inverters. I would consider a 6K SunnyBoy6000TL-US-22 for a system your size. It is the only family of inverters that can provide 1500W of 120v AC if the grid is down. If i was using Micros I would use either Enphase M215 or M250 depending on the panel

Andy

 

[solidstate]

I have been interested in solar power for many years and I have tried to keep up to date.

The hardest part will be the actual, physical installation of the panels. They have to be mounted very well! Imagine a sheet of plywood on top of your car driving down the highway! I was just talking with an installer and I was told the panels are strong enough to walk on (not that you WANT to do that). The trick is to make sure the panels are securely mounted to a frame and the frame is securely mounted to something else. I was told that if everything is done right, the panels can withstand 110 MPH (180 KPH) winds.

The decision YOU have to make is if you want to do the research to find all the proper mounting hardware (stainless, correct threads, correct strength, etc.) and do all the physical work to install the panels, and making sure you seal any fasteners penetrating the roof.

If you have some reliable help and the time, I would say go for it. I would not recommend doing it by yourself. The panels are big and awkward to handle. Working on roofs can be "exciting." Renting some equipment will make the work MUCH easier!
http://www.genielift.com/en/products/scissor-lifts/slab-scissor-lifts/index.htm

AFAIAC, the electrical part is not a big deal. If you are working on IP cameras and building networks, the wiring should not be a problem for you. You just have to make sure you do the wiring to code and there are plenty of guides for this. In fact, since many municipalities incorporate the National Electric Code into their ordinances, you can (should) be able to get a copy of the code for free. Here is my favorite:
https://archive.org/details/USGovernmentDocuments
Here is another (annoying) way:
http://www.oneprojectcloser.com/free-copy-of-the-2008-national-electrical-code-nfpa-70/

Here is another useful site:
http://www.iccsafe.org/content/pages/freeresources.aspx

You MUST make sure you do everything according to code. Not because it is better, safer, stronger, etc., but because there is an army of fascist minions (building inspectors, Realtors, Loan officers, Insurance agents, etc., etc., etc.) whose sole reason for existence is to extort fines from you if you do not build to code.

I do not know much about micro-inverters.
For standard inverters the best brands are SMA (formerly Sunny Boy, German owned company and $$$$, built like a Tiger Tank!) and Zantrex. You can get just about any size or configuration from these companies. They both have been around a long time and have excellent reputations.

I would suggest at least a small battery bank. Then you will always have power. Grid-tied inverters will not operate if the grid is down. There are some new battery technologies on the horizon that look very promising. Here is one:
http://www.aquionenergy.com/energy-storage-technology

If you know anyone else interested in solar you can buy a pallet of good Chinese panels for a good price. Do a web search and you will find many dealers. The Chinese make some excellent panels for great prices (like their IP cameras?).

A good place to start your research is Home Power:
http://www.homepower.com/
They have been around since 1987. Sometimes they are too "Granola" but they have very sound information.

 

[Andy]

I have been interested in solar power for many years and I have tried to keep up to date.

The hardest part will be the actual, physical installation of the panels. They have to be mounted very well! Imagine a sheet of plywood on top of your car driving down the highway! I was just talking with an installer and I was told the panels are strong enough to walk on (not that you WANT to do that). The trick is to make sure the panels are securely mounted to a frame and the frame is securely mounted to something else. I was told that if everything is done right, the panels can withstand 110 MPH (180 KPH) winds.

The decision YOU have to make is if you want to do the research to find all the proper mounting hardware (stainless, correct threads, correct strength, etc.) and do all the physical work to install the panels, and making sure you seal any fasteners penetrating the roof.

If you have some reliable help and the time, I would say go for it. I would not recommend doing it by yourself. The panels are big and awkward to handle. Working on roofs can be "exciting." Renting some equipment will make the work MUCH easier!
http://www.genielift.com/en/products/scissor-lifts/slab-scissor-lifts/index.htm

AFAIAC, the electrical part is not a big deal. If you are working on IP cameras and building networks, the wiring should not be a problem for you. You just have to make sure you do the wiring to code and there are plenty of guides for this. In fact, since many municipalities incorporate the National Electric Code into their ordinances, you can (should) be able to get a copy of the code for free. Here is my favorite:
https://archive.org/details/USGovernmentDocuments
Here is another (annoying) way:
http://www.oneprojectcloser.com/free-copy-of-the-2008-national-electrical-code-nfpa-70/

Here is another useful site:
http://www.iccsafe.org/content/pages/freeresources.aspx

You MUST make sure you do everything according to code. Not because it is better, safer, stronger, etc., but because there is an army of fascist minions (building inspectors, Realtors, Loan officers, Insurance agents, etc., etc., etc.) whose sole reason for existence is to extort fines from you if you do not build to code.

I do not know much about micro-inverters.
For standard inverters the best brands are SMA (formerly Sunny Boy, German owned company and $$$$, built like a Tiger Tank!) and Zantrex. You can get just about any size or configuration from these companies. They both have been around a long time and have excellent reputations.

I would suggest at least a small battery bank. Then you will always have power. Grid-tied inverters will not operate if the grid is down. There are some new battery technologies on the horizon that look very promising. Here is one:
http://www.aquionenergy.com/energy-storage-technology

If you know anyone else interested in solar you can buy a pallet of good Chinese panels for a good price. Do a web search and you will find many dealers. The Chinese make some excellent panels for great prices (like their IP cameras?).

A good place to start your research is Home Power:
http://www.homepower.com/
They have been around since 1987. Sometimes they are too "Granola" but they have very sound information.

Just a couple of comments.

Wiring a 600V DC System is very different that wiring low voltage Ethernet wiring.

SunnyBoy is a brand of SMA which is a very good inverter. The new SunnyBoy's are made in the US. The new SunnyBoy 3000,3800.4000,5000 & 6000TL_US-22 are dual MPPT, have very low start voltages and can produce power down to 125 V string voltage. They also have a feature allowing them to track the maximum power point when some of the panels are shaded. The -22 indicated that they have Arc-Fault protection and comply with the 2011 NEC code. One additional feature is the ability to put out 1500W of 120V AC when the grid is down without battery backoup,

To the best of my knowledge Xantrex now owned by Schneider does not make a grid tied inverter but focuses on off grid and battery backup systems.

Other major brands of grid tied inverters are ABB (Power One) and Fronius.

Unless you are running a DC Coupled system with a charge controller I would not suggest a battery bank They happen to be one of my specialties and are not simple. controlling the charge and not overcharging is fairly involved. SMA makes a SunnyIsland Battery Inverter which couples with a SunnyBoy and has built in communications between the SunnyBoy and SunnyIsland to regulate state of charge via frequency shift on the AC side.


Mounting the panels at least in Conn requires a PE stamp on the drawings. Typically we run 3 1/2" 5/16 stainless lag bolts with 1 1/2" minimum thread dept in wood. In the softest species of wood this provides over 300 pounds of pull out strength where as if you mount the panels 4 " off your roof with L Feet (anchors) every 48" the max uplift with 110 mph sustained wind is under 70 pounds per L foot.

 

[solidstate]

Just a couple of comments.

Wiring a 600V DC System is very different than wiring low voltage Ethernet wiring.
<snip>

This is absolutely true and safety should not be neglected.

BUT, if you have read networkcameracritic's blog you will know he is not stupid and I assume he will be able to avoid electrocuting himself or accidentally arc-welding his solar panels together.:laugh:

I also assume he is smart enough not to work on the system while it is energized. I will mention the tip of covering the panels with a tarp to "turn off" the panels.

I guess my attitude is, if you think you can do it, go for it! If you are smart you will do fine. If you are not smart...., well, the gene pool can always use some cleaning.

 

[networkcameracritic]

i decided to go with a solar company that was on the same page as me and run by geeks instead of marketing and sales. Going to run me $3.22/W with LG 280W panels and the SMA 6000TL inverter with the off-grid power panel so you can use it in the event of a grid power outage. Passed the first round of approvals, the HOA, now waiting for the designer to draw the plans for city approval. Should have it all working by the time my usage is at it's minimum, LOL.

 

[nayr]

awesome, give us some feedback when your done.. I think alot of us here are wanting to jump into solar but are waiting for things to kinda plateau; seems like were on that cusp where new tech is starting to slow down and production is high... I think its a good time to buy into it finally.

 

[Andy]

i decided to go with a solar company that was on the same page as me and run by geeks instead of marketing and sales. Going to run me $3.22/W with LG 280W panels and the SMA 6000TL inverter with the off-grid power panel so you can use it in the event of a grid power outage. Passed the first round of approvals, the HOA, now waiting for the designer to draw the plans for city approval. Should have it all working by the time my usage is at it's minimum, LOL.

You've made a good choice. That is a GREAT price. I'm installing a pair of SunnBoy 6000TL-US-22 's on my house next weekend. Their sitting in my garage now. I was going to use 40 SunPower X21-335 panels but decided at the last minute to change to 60 PhonoSolar PS250P-20/U panels due to cost. I'm running an east-west array.I managed to convince one of our roof crews and production manager to "help" me next Saturday.

The LG panels are very good and will work out well with the SunnyBoy. My wife didn't like the white backsheet on the LG Panels otherwise I would have used them.

One of the reasons I like that model SunnyBoy is that it starts at 150 V and stays running down to 125 V string voltage meaning that you get power both earlier and later in the day than with most inverters. You pick up a slight gain in production if you string that inverter with one long string approaching temp compensated Voc and one shorter string.

SMA is also coming out with a 7600 in the same series.

I'll post some pictures of my system once installed.

 

[fenderman]

@Andy what is the average lifespan of these solar systems?

 

[networkcameracritic]

We have a solar system at the community pool we put in 15 years ago, 100W panels and still producing power and more than paid for itself 2-3 times over. LG does make those panels with black backsheets but when they told me you lose 10W a panel and I'm not really ever going to see the panels, I opted for the 280W panels with the white backsheet. SunPower does make the most efficient panels but LG had good enough efficiency for a better price per watt. The plans were submitted to the city on Monday. I'll see if I can get a timeframe from them next week.

Just to show you the insanity of my Aug/Sep electric bill, 39 cents a KWHR on tier 4, almost 33 cents a KWHR average, hence the quick ROI;

 

[icerabbit]

1500 kWh adding up to a $500 electric bill is insane! No wonder you are looking at solar! I would too! I thought we had expensive electricity with a peak combined rate of ~19c (last time I looked), before some account and nuisance charges; which add up to: for 1500 kWh ~ $200 and 2500 kWh $400. In northern New England. Having a house that was designed during the electric boom (with the promise of flat fee electricity rates) with all electric heating; the service line, panel etc are obviously larger than avg and guess what, they charge sales tax on the account since the it is considered commercial. Never mind that it is still a private residence in a residential area.

 

[networkcameracritic]

Trust me, for me it's all about ROI. If my electric bill for 1,500KWHR was $200, there's no way I could justify Solar. To get my bill to even that low I had to install the most expensive A/C possible for it's efficiency, more efficient appliances, converted electric cooktop to gas and install all LED lighting, even landscape lighting. Before that we had $600/mo bills in the summer when rates were 26 cents for tier 4. I love it when you go buy an appliance and it has the yellow sticker that says it's going to cost $54/yr to operate until you read the fine print and it's based on an electric rate that's 1/4th what I pay.

 

[fenderman]

You are so right about those stickers being misleading...i think they base it on 11c a kwh....aside from that, the number is based on the "Standard" settings...so if you turn your fridge up higher or use your tv more that x amount of hours a day...the numbers are very different.

 

[Burbo]

Wow I had no idea how good we have it in my area of Tejas or how high it is other places. I just paid August bill, 2453 kwH for $244.00. At that rate solar will never an incentive here. Ours may go up soon since the boss man said that global warming is one of his top priorities. We have some coal and a lot of gas fired plants. Now i guess it all evens out since I heat with propane and that can really be a kicker sometimes. When we built in 2002 it was $.50 per galllon. Last year I pre-bought on contract and got a great deal at $2.35 per gallon. If I had it to do over, I would build small and super efficient.