Choose DIY to Save Big on Solar Panels for Your Home!

Consider installing your own solar electric system. Doing the work yourself can add up to serious savings.
By Gary Reysa
June/July 2011
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Gary Reysa’s solar electric system includes 10 photovoltaic panels. Altogether, this system produces about 3,300 kilowatt-hours of electricity per year.
PHOTO: GARY REYSA
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Have you been thinking about installing solar panels for your home, but been discouraged because the cost is too high? Here in Montana, my family and I saved 40 percent on the cost of a solar electric system by buying a kit and doing the installation ourselves.

One notable feature of our solar power system is that it uses the relatively new micro-inverter technology. With this system, each photovoltaic (PV) panel has its own grid-tied inverter that is mounted right by the panel. This kind of system is easier for do-it-yourselfers to install, and has other advantages, such as less sensitivity to partial shading, power output optimization for each PV panel, and the flexibility to start small and grow the system as time and budget allow.

We decided to go with a grid-tied system, which is much more cost effective than an off-grid system. One advantage is that you don’t have to buy batteries, which are expensive and have to be replaced from time to time. You can also choose to install a smaller, less expensive system that generates just a portion of your electricity. On the downside, grid-tied systems provide no electricity when the power grid is down.

Planning the Solar Electric System

The first step to planning your system is to evaluate rebate options and obtain permits. Your local power utility has rules you must follow when you hook the finished system to the grid, and building codes may also apply. In addition to federal incentives, states (and even some cities) offer rebates to help with the cost of the system. Understanding the local rules before you start will save you frustration later.

Most utilities will have an information package and a person who specializes in the utility requirements. We found our local utility and code inspectors helpful and friendly. We didn’t pick up a hint of resistance from them regarding the idea of a homeowner-installed PV system. Permit costs and turnaround times were small. Check the Database of State Incentives for Renewables and Efficiency (DSIRE) for information on rebates in your state.

Deciding the size of your system is the next step. With a grid-tied system, size is less critical, because the grid supplies power when your PV system falls short. Systems as small as a couple hundred watts are practical, but you can also install panels that will produce enough electricity for all your needs. Review how much electricity you use now, and then estimate what you will be able to save by applying conservation and efficiency measures throughout your home. This will give you an idea of how big a system you’ll want to build. You certainly can build a system smaller than this, but it may not pay to install a larger one. Look up your state on DSIRE to learn about net metering rules where you live, including how much you can get paid for generating excess power.

Figuring out ways to use less energy in your home is almost always more cost effective than putting up a larger PV array. We started with a monthly usage of 1,000 kilowatt-hours (kwh), which is about average for a U.S. household. We got this down to about 500 kwh by spending a bit more than $1,000 on efficient lights, power strips with switches, a new fridge and a few other strategies (see 8 Easy Projects for Instant Energy Savings). Compare that with the PV system, which saves us 250 kwh per month but costs $6,000 — it’s clear where the best return is. Take the efficiency measures first, then buy the PV system.

We planned for a PV system that would cut our current usage by about half (i.e., a system that would generate about 250 kwh per month, or 3,000 kwh per year). We used the National Renewable Energy Laboratory’s PVWatts calculator to estimate the size of a system that would produce 3,000 kwh per year in our area. PVWatts came up with a system size that was a little more than 2 kilowatts. The system we ended up installing has an estimated production of 2.15 kilowatts.

Our system uses Enphase micro-inverters, but other brands may also be available. We have 10 PV panels rated at 215 watts each, and each has a 190-watt inverter that converts the direct current produced by the panels to alternating current, which is the standard system for electricity in homes in the United States. We ordered the system as a kit that included the PV panels, micro-inverters, mounting rails and a number of other parts. The kit was a good choice, but don’t expect an “insert-tab-A-into-slot-B” sort of kit. Basically, you get a box full of parts. You’ll soon become familiar with the websites of the companies that manufacture the parts — especially the “download manuals” area.

Situating the PV Array

Ideally, the solar panels for your home would face south, and be tilted at an angle about equal to your local latitude. They would also be in full sunlight with no shading from about three hours before solar noon (the time when the sun is directly in the middle of its path across the sky on a given day) to three hours after solar noon. Performance will not suffer much if you can’t get the panels aimed straight south or tilted just right, but even a small amount of shading can have a serious negative effect.

A solar site survey will show you any potential shading problems for any time of year. You can do the site survey in a couple of ways. One way is a procedure in which you use a “sun chart” for your area and a simple sighting of objects that may cause shadows — this could be a fun family event to teach everyone about the path of the sun throughout the year. Another simple method is to model your PV array and potential shading objects in the free Google SketchUp drawing program. SketchUp has a feature that will show you shading patterns for any time of day and year.

Micro-inverters offer an advantage in partial-shading situations because, in this system, each PV panel has an inverter that provides maximum power point tracking to get the most possible power out of that panel, whether it’s partially shaded or in full sun. For conventional string inverter systems, partial shade can cause the voltage of a string of panels to drop to the point where the inverter shuts down and power output drops to zero — a big effect, indeed. If you have serious shade problems that you can’t amend, PV is probably not a good choice for your situation.

We opted for the ground mount rather than a roof mount because it made the installation easier (and less scary), and we won’t need to remove the panels if the roof ever needs to be replaced.

Solar Panel Installation

It’s time for the fun part — installing the system! You could build or buy many types of PV panel mounting systems, but the PV panels will probably last 30 years, so choose a mounting system that can endure wind and weather for a long time. We made our own mounting rack from 4-by-4 treated wood posts and concrete footings, then installed the panels on aluminum rails designed specifically to support the panels over the wood frames.

With some help from the neighbors and a borrowed concrete mixer, we installed the mounts fairly quickly. It’s important to make sure the mounts are aligned well. We used temporary 2-by-6 frames behind the vertical posts to align all the support frames.

Be sure the joints in the wooden frame are reinforced with metal plates and that the footings are adequately sized. Apply an extra coat of wood preservative to all grain ends of the treated wood and the areas where the wood comes in contact with the concrete. In our climate, treated wood lasts a long time, but if you live in a wet climate, you may want to consider metal supports.

After the mount frames were in the ground, we installed the aluminum support rails. This was easy to do using the supplied L brackets. We then installed the micro-inverters on the rails, which required only two stainless steel bolts for each inverter.

Next, we installed the PV panels, starting at one end and working across the rails. Be careful! One slip may cost you a $600 PV panel. The panels are awkward to handle, so having assistance with this part is important. We temporarily clamped a 2-by-6 below each panel to support it while making the final adjustments. The mounting clamps simply slide into slots in the support rails. After the PV panel is in place, the clamps can be tightened to secure the panel.

Check the alignment frequently as you mount the panels. Small errors in alignment add up and tend to be noticeable. We tightened the panel clamps just enough to hold them in place, and later used a torque wrench for the final tightening.

PV System Wiring

The wiring for the Enphase system is relatively simple, but be sure to read all the instructions and understand the safety issues. You are dealing with high voltages, and the PV panels make the system “hot” even if it’s not hooked up to the grid. If you think this may be more than you want to tackle, you can team up with a local electrician to do the wiring. The actual labor involved in wiring is not much, so this shouldn’t add significantly to the cost of the system.

The output wires from each PV panel plug into the mating wires on the micro-inverters. The output cables from the micro-inverters are just daisy-chained together. The output from the final inverter goes first to a junction box at the PV array and then to a PV array disconnect switch located near the house meter. From the disconnect switch, the power goes to an unused circuit breaker in the circuit breaker box.

The PV array disconnect switch allows utility workers to disconnect the PV array from the grid. The switch must be lockable, it must be near your main house meter, and it must be clearly labeled. The circuit breaker that feeds PV power into the circuit breaker box must also be labeled.

I plugged in the PV panels and the new circuit breaker last, so nearly all the wiring was done on a “dead” system.

Grounding the System

Check all of your wiring, and be certain that you have everything grounded as required. All of these components (PV panel frames, PV panel support rails, micro-inverter cases, PV array junction boxes and the disconnect switch) must be grounded by an approved grounding method.

For example, even though the PV panels are bolted to the grounded rails, this is not an approved grounding connection. We used the Weeb grounding system for most of these, and it worked well.

In addition to safety issues, inspectors will look for proper grounding. If I were to do it over, I would use the Weeb system everywhere because it’s so easy.

More detailed construction information is available at Build It Solar.

Start Up the Inverter

For Enphase systems, a unit called the EMU communicates with all of the inverters by sending signals via the power line. The EMU provides information on how the system is functioning, checks the status and health of the inverters, and sends the data to the Enphase server through your home Internet connection.

After the inspector approves your system and the utility provider has installed the net meter, you can turn the system on and plug the EMU into a regular power outlet. The EMU will find your inverters and start reporting. At this point, the system is generating power, and the EMU will give you the basic stats. Sit back, have a beer, and watch the power roll in.

PV Performance and Savings

Our system has been operating since November 2009, and its performance has been good. We’ve experienced no failures, and the system hasn’t required maintenance. So far, the energy production is running about 10 percent ahead of the PVWatts calculator estimate. Check out the real time performance of our system anytime.

The cost of our system was $9,960, or $4.63 per watt — prices may be a little lower now. The 30 percent federal rebate plus a $500 state rebate brought the cost down to $6,470, or $3.01 per watt. Rebates in some states are much larger than those in Montana.

Professionally installed systems of this size are often quoted at $7.50 per watt, which would mean we saved about $6,000. If cost is your main motivation for assembling a system yourself, I recommend getting bids on installed systems and comparing them with the cost of all the parts you’d need for a similar system.

The savings on our electric bill the first year was $332 (based on about 10 cents per kwh), plus we reduced our CO2 emissions by 4,700 pounds. The simple payback period on the $6,000 we invested would be 18 years, but I expect it will be much shorter if the price of electricity continues to increase. For example, if rates go up 10 percent per year, the total payback time will be only 11 years.


Solar Power Sources

Construction Details 

PVWatts Calculator 

Real Time Performance 

Solar Site Survey 

Database of State Incentives for Renewables and Efficiency 

Weeb Grounding System 

Wholesale Solar (kit source) 


Gary Reysa has developed all sorts of DIY projects to harness power from the sun to heat his home, shop and domestic hot water — and to produce electricity. His website, Build It Solar, is an outstanding resource if you’re planning a project of your own. 


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Post a comment below.

 

Realsteals
7/15/2014 1:04:09 PM
I've come across many tips and strategies to help save on electric, and they all only saved me just a few dollars. So i went and did some research and found this cost efficient DIY Guide to living off the grid. Here's the link: http://tinyurl.com/l7ynhpc

setrs
7/15/2014 6:40:47 AM
Solar PVs are big time investments that yield FIT payments of course from a self-owned and installed system. Lately people are going in for energy maximizing devices such as solarimmersion to speed up the ROI of the panels.

Elizabeth
6/22/2014 10:11:37 AM
It's a good article. Nowadays, the fear of the costs of implementing the solar pv system prevents people from actually becoming more environment-friendly. The truth is, the price of it is gradually falling and more tools are available, like the apps so helpful with designing the pv system, with this one http://easysolar.co it gets much easier

kristahiles
2/11/2014 3:58:30 AM
http://www.sterling-energy.com/services/management-and-technical-consulting-services/ are in great demand and the cost has also reduce as compared to earlier. They help a lot in energy saving and easy to pocket as well and also helps in saving money from electricity bills

BobbyOre
11/29/2013 1:46:38 PM
If your really looking to save a bundle, check out this DIY guide to building your own solar panels! You can effectively make your whole home self sufficient and never pay the power companies again! and the best part is your can do it on ANY budget! Check it out! http://572fcylqlay9y3o3kfvbjs0u7x.hop.clickbank.net/

SacramentoSolar
11/25/2013 8:01:52 PM
Sure, you can buy solar panels, but you are foregoing many warranties that a professional installation company can offer you:

- Roof Warranty
- Production Warranty
- Transferability (if you move)
- etc.

You might save upfront, but will it be worth it if you panels start underperforming, your roof ends up leaking, or the panels completely bomb?

Think about that before you decide for the DIY option.

Mark
http://www.youtube.com/watch?v=y-ZWkLUYo0c

DJ
10/30/2013 8:09:32 AM
Hello.I want to turn my power in to solar and let the power co pay me..lol right..anyways I went to a few site and to a test to see what size system I needed for my plan... it showed me this...You will need a system producing 22.92 DC kW to cover 200% of your monthly power usage...Now I have no idea what system I need.I used 200% to make sure I have no bill.If you have a good idea which system would be best please help..Thank you

Michael8310
5/27/2013 10:24:45 PM

I see that this article was written quite a while ago, but I've been looking around for home solar arrays and they've gotten a lot cheaper since then.  Today I figure that this system would cost about 3790 (minus the wood, cabling, and grounding method.)  Edisonsolarsales.com has the cheapest prices I've found when I've been looking around.  Here's what it would cost to build this with them now:

9 250W panels at 229.32 ea: 2063.88

9 Enphase M215 Microinverters at 156 ea: 1404

4 16' mounting rails (2 on top, 2 on bottom) at 43 ea: 172

2 splice bars to connect the rails together at 6 ea: 12

16 L-feet to mount the rails at 8.50 ea: 136

If anyone is looking to put a system in soon, I've heard that panels are about as cheap as they're going to get with the anti-dumping laws raising import taxes on Chinese-made panels and with subsidy funds starting to run out. 


fshefman
5/24/2013 2:47:17 PM

Interesting article and you can always do it yourself, but I would be concerned the most about  the electrical.  You are dealing with high voltage which can be deadly for you and your family through electrocution or fire.  In my location Ontario, Canada, you would need an certified electrician to do at least that part of the install and you must pass electrical safety authority inspection at various stages.  I have a system on my roof operating for the past year, but had it installed professionally and I'm glad I did.  There is a significant cost and benefit to hiring a pro. As for micro-inverters (DC-AC) or Optimizers (DC-DC), I put in Solaredge Optimizers and don't regret it. Primary advantage from my side  was the fire safety aspect which is not discussed very often. However if I had a truly south facing unshaded location I would consider an inverter with strings coming into it. I think now with the new NEMA requirements inverters can deal with DC arc fault. I have a blog describing my challenges putting together my system and its subsequent operation at http://solarinstall.blogspot.ca/.  It might be helpful if considering a solar system for a house/roof.


JOHN & VIRGINIA LEDOUX
2/8/2012 10:49:39 PM
Abbey, your are right, just follow the money.

ABBEY BEND
2/8/2012 4:03:23 PM
One word, Solyndra. Fine and common example of the solar industry and government political kickbacks. I am always happy when people can be hired, especially in Bozeman, been through there many times, beautiful and remote. Yet the waste of taxpayer money is too great. Also, there are no 97% serious climate scientist out there, just liberal hogwash, not supported by facts, just lots of spin. The IPCC really, what do the hair dressers on the panel really know about climate theory?

Gary Reysa
8/25/2011 12:08:08 PM
Hi again Abbey-- On the climate change issue, I'm going to go with the 97% of serious climate scientist and the IPCC findings that say the earth is warming in an unprecedented way, that elevated CO2 levels are the main cause, and that human activity is the main cause for the elevated CO2 levels. On the issue of incentives, I understand your arguments and I think they have merit, but I think think that the positive arguments for incentive programs (stated below) outweigh them. I know several people right here in our small town of Bozeman who are growing their renewable energy businesses and hiring people, and who would not be in business without the incentives to get them started. Wiring the system is something people do want to be careful about, but there is no need to work on a hot system at all if you follow the sequence I describe.

Gary Reysa
8/25/2011 11:42:50 AM
Hi Abbey -- Just to address the most straight forward point first: It is actually very difficult to build a PV panel from wafers, and its even more difficult to seal and frame it well enough to get a descent life. I've talked with several people who have tried it, and they all said that it was a fun and educational project to build a panel, but completely impractical to build a full array. In case you want to test this yourself, here are some plans: http://www.builditsolar.com/Projects/PV/pv.htm#MakePV have fun :)

Abbey Bend
8/24/2011 7:29:20 PM
Water vapor is number one and Methane is number two, CO2 is far down the list and there is little to no evidence of it causing global warming, and we are in an interglacial period, so it is expected we will show warming, still lower overall temperatures than during the time of the Vikings growing grapes in Greenland, now the sun is a different story. So that is a very poor reason for a solar panel, that when one looks at the total expenditure of CO2 to produce, site and install them, as well as maintain them, it is questionable at best they reduce any CO2 emissions to total. Also if one wants to have a solar array, the least expensive method is to simply build the entire array yourself, buy passing the assembler in China or Germany. They are very easy to build, and I agree, not that hard to install, but nerve wracking for someone that does not understand how to handle a hot system. There can be no mistakes with a hot system! So reasonble article as far as it goes, but even in limited space, I think several other points could be hit upon.

Abbey Bend
8/24/2011 7:20:57 PM
Gary, Good basic information about solar PV panels in some ways, not very good in some ways. I have to side with Kurt on his comments, also T. Brandt. The tax credits are one more example of entitlements, which are a parasitic load on our economy. More over the "green" jobs so highly spoken of are for the most part being shipped to China. Panels are mostly made in China, as are most PV cells, yes a few are made other places but not many. So all that really happens is the tax credits end up benifiting China, not the United States. As you mention, limited space here, but those are the numbers, being both a Chemical Engineer and a contractor, I also know how to run a column of numbers. I will not say your numbers are incorrect, but they are what I see as somewhat skewed, so possibly misleading. I can see both sides of this equation. The side I mostly see is this is not particularly cost effective when all of the numbers are put into play. If one looks at the actual cost of production, the overall drag on our economy, caused by the overspending by the government, the over stated electrical costs over then next several years, it is hard to make the case. Also when a person looks at our historically low atmospheric CO2, levels http://www.geocraft.com/WVFossils/Carboniferous_climate.html and NASA's latest information, http://news.yahoo.com/nasa-data-blow-gaping-hold-global-warming-alarmism-192334971.html Couple this with the fact that CO2 is one of the least of "greenhouse" gases.

Gary Reysa
6/13/2011 9:41:59 AM
Hi Kurt, OK, I see how you got the 2940 KWH number, but that is not an accurate way of determining the yearly output. Here in MT, the summer month output is typically nearly double the winter month output, and time period you used includes two winters and only one summer -- the only fair way to evaluate a system like this is over full year periods. For the first year, I kept a spreadsheet to keep track of the energy output, and I assure you again that the output for the first full year was 3320 KWH. I've been an engineer for going on 40 years, and I do honestly know how to sum up a column of numbers. We will see in Nov what the output for the 2nd year is -- I do expect it to be down a bit from the first year as we have had a literally record setting stormy winter and spring. On the inverter choice, when you look at whole system grid tie prices at WholesaleSolar, the price for the SMA equiped 2300 watt Kyocera panel equiped system is $3.40 a watt and the price of the Enphase equipped 2115 watt Kyocera panel equiped system is $3.22 a watt. Adding the EMU to the Enphase system would bring it up to $3.38 a watt -- so, apparently, not much difference when you buy a whole system. Again, I think both the inverter technologies are fine, and people should look at their situation and pick the best one. If a string inverter works well in a given situation and saves some money, that's great -- it makes the whole system pay better. As far as "playing down the complexity of the installation", I just do not see that I did that. In the article I included as much detail as I possibly could to give people a realistic idea of what exactly in involved, and on the website there are 60+ pages that go into great detail about each stage of designing, permiting, and building the system. Its the most complete and detailed description of a PV installation that I know of. If you read over that 60 pages on the my website and have suggestions on what additional infor

Kurt Johnsen_2
6/12/2011 2:10:21 PM
Gary, Full disclosure; I am a state certified solar contractor and a state certified building contractor in Florida. I have been in construction for 30 years and have run my own construction business for 22. However, because I took a critical look at your article doesn't mean I have a low opinion of people doing their own projects. What I am concerned about is the use of inaccurate numbers and the downplaying of the complexity of a solar installation in a trusted and widely read forum like Mother Earth. As to your suggestion that my numbers are off base; If I use your referenced supplier (Wholesalesolar) I can show that my 50% statement that you said ‘sounds way high’ is actually an understatement. An SMA 3,000 inverter which can handle 15 of your 215 watt panels costs $1,587. 15 Enphase inverters cost $3,000. That's an 89% premium to go the Enphase route (when there wasn’t an apparent need to). You say you don’t know where my 2,940 number comes from; It came your real time monitoring website. Take the “current reading” of 4,670 divide by the 19 months of service x 12 months = 2,940/ yr. Also, if you click on "12 months" it reads 2,950. I went to your website for the PV Watts est. of 3,073kwh/yr. Your own data shows 5% under-performance not the 10% outperformance your article states. I am all for promoting solar and DIY but I am afraid of people being led to underestimating the pitfalls, variables and dangers of solar installs by folks who don't know what they don't know.

Gary Reysa
6/10/2011 7:49:56 PM
Hi T. Brandt -- I guess we differ on the incentive programs. I think that incentive programs to give industries that we would like to see develop because they benefit the country are sound investments. If you look at the just amazing increase in capability of the equipment, production rates, and substantial price reductions the progress of the PV industry has been very impressive. I think that many would conclude that the incentive programs have had a big part in in the progress, and are building an industry that is very important to our energy future. These programs are basically programs that we the taxpayers bring into being because we believe the money is well spent. the programs have a very high acceptance rate among taxpayers. I think you better check your math on $10K at 5% for 30 yeares -- I get $43K -- not $218K. But, I did not spend $10K, I spent $6K and the simple payback period is 18 years not 30 years. $6K invested for 18 years at 5% is $14K. From my retired knothole, the ability to keep control of my energy costs over the years as well as reduce CO2 emissions by nearly 5000 lbs a year is well worth the investment. Besides the financial aspect, I found it to be a lot of fun and very rewarding to learn this technology and to build the system with my own hands. Clearly this is not for everyone, but I think a lot of people would enjoy such a project. Gary

Gary Reysa
6/10/2011 7:16:13 PM
Hi Kurt -- The 50% sounds way to high to me, the price I just checked at WholesaleSolar was $0.95 per watt for the micro inverter and $0.78 per watt fro the Fronius. That's about 20% more and you just have to wiegh your individual situation to see if the shading or ease of epansion or ease of wiring make that 20% worthwhile. My feeling is that both technologies are fine and work well -- just pick the one that suits. I don't know where you are getting the 2940 KWH -- it currently shows 4670 KWH -- not 2940. I assure you that the 3320 KWH for the first year is accurate. It IS about 10% above what PVWatts predicted and this inspite of record stormy weather for the year (you have proabably been reading about our floods from the recrod snowfalls). You understand that in a magazine article that there is a limit to how much space you have to go into construction detail -- the link to the more detailed description on my website gives 68 pages of very detailed information on building the system -- its basically a book :) You obviously don't have a high opinion of people doing their own projects -- I guess we just have to disagree on that point. Best -- Gary

Gary Reysa
6/10/2011 7:01:26 PM
Hi Tom, The micro inverters have same efficiency as the larger string inverters. One of the reasons I choose the Enphase inverters is that they are rated to the full temperature range that we get here in Montana whereast the larger string inverters are not, and would have to have been installed in a protected location where I am -- this would have been inconvenient and somewhat expensive for me. To my knowledge they can only be used on grid-tied systems. If you want an off-grid solution, I think you will have to look elsewhere. In our case the grid power is pretty reliable and we use a small generator on the rare occasions when the grid goes down. Gary

t brandt
6/10/2011 6:11:32 PM
Other shortcomings of the financial analysis: -the govt rebate amounts to parasitizing the taxpayers to your selfish advantage, and the capital spent up front means either taking out a loan to be paid back with interest or using cash that could have been invested and paying interest over the lifetime of the installation- which has to be replaced every 20 to 30 yrs. [$10,000 invested @ 5% turns into $218,000 after 30 years!]Subtract that loss from your balance sheet on PV.

Kurt Johnsen_2
6/10/2011 3:01:06 PM
Microinverters cost about 50% more are unnecessary in a field where there is no shading. You can lose more $ due to relative voltage drop over distance like a field.This system can expanded by 5 more panels. So could a central inverter. There is precious little structural detail. No mention of snow loads, wind loads, etc. Author states exceeding the 3,000 kwh/yr design by 10%. Their real time data shows 2,940. That is 2% below, not 10% above. The 2,150 watt system x pro cost of $7.50 = $10,788 after rebates. Subtract their cost of $6,472 = $4,316 savings (not $6,000). The article stated .10/kwh electric cost, that they saved $332 last year and that simple payback would be 18 years. Using the real time production rate for the last 19 months of 2,940 watts/ yr X .10 = $294/ yr. Total cost of $6,472 divided by $294/ yr = 22 years (not 18). The author doesn’t mention how many total man hours it took to plan, research and complete the project or how much of the savings were due to not paying for liability or workman’s comp insurance, or for engineering. If you risk losing your life savings while making minimum wage doing a project that may fail or return less over time because of your lack of expertise, that’s not a bargain. I think it is a disservice to use inaccurate numbers to exaggerate the benefits of solar and going it alone. I also think there should have been a statement about the author's lack of training and experience in the feild.

Tom Cox_2
6/10/2011 2:36:00 PM
The on-board inverters are an interesting, new angle. Are they efficient? Hardy in typical outdoor environments? Are they only applicable to grid-tied systems? I can see some advantages off-grid, if they can synchronize among themselves to tie several panels togwether, because of the reduced resistive losses of AC versus DC if the power is "piped" some distance to a battery shed or breaker box. Circuits that are isolated completely from the grid, or in an off-grid structure would be my application. I'm on-grid, but with an unreliable provider. A little AC in daylight, with the option to rectify and store power in batteries, is a lot better than nothing. Thanks for the thorough and interesting article. -- TC








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Lighten the Strain on the Earth and Your Budget

MOTHER EARTH NEWS is the guide to living — as one reader stated — “with little money and abundant happiness.” Every issue is an invaluable guide to leading a more sustainable life, covering ideas from fighting rising energy costs and protecting the environment to avoiding unnecessary spending on processed food. You’ll find tips for slashing heating bills; growing fresh, natural produce at home; and more. MOTHER EARTH NEWS helps you cut costs without sacrificing modern luxuries.

At MOTHER EARTH NEWS, we are dedicated to conserving our planet’s natural resources while helping you conserve your financial resources. That’s why we want you to save money and trees by subscribing through our earth-friendly automatic renewal savings plan. By paying with a credit card, you save an additional $5 and get 6 issues of MOTHER EARTH NEWS for only $12.00 (USA only).

You may also use the Bill Me option and pay $17.00 for 6 issues.