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One of the most common questions we get from prospective customers is “can I just purchase solar panels and install them myself?” The answer to this question depends on a number of factors, chief among them being the amount of time, effort, and energy that a person is willing to devote to the project. A lot of people who are considering doing the installation themselves think the process is as simple as installing some rails on their roof, mounting the panels, and running a few wires into their breaker panel. However designing and installing any photovoltaic (PV) system is vastly more complicated than that. So let’s examine everything that actually goes into properly designing and installing a solar array!
The first step is to select the type of modules, invert(s), and racking to be used for the system. Additionally there are dozens of other components that will need to be purchased and properly configured with one another, from panel clamps, to grounding lugs, to a laundry list of electrical components. All of these products range greatly in terms of price, quality, size, warranty coverage, and compatibility with one another. However once these items have been selected, the installation is still a long way from beginning. Before any of the materials are ordered, three things are needed: an engineer’s stamped letter, a building permit from your local authority having jurisdiction (AHJ), and approval from your utility company (assuming the system will be grid tied). In order to obtain any of these three things a set of detailed design specs must be submitted. These designs must show: the proposed location, tilt and orientation of the array, string size, wire size, inverter size, breaker size, proper grounding, wire configuration, voltage drop calculations, and production calculations, just to name a few. When it comes to configuring a PV system an immense amount of knowledge is required not only to remain code compliant, but also to ensure the highest level of production from the system. If any one component is not properly sized or configured you could not only be losing power production, but could also be creating a potential fire hazard.
Once all the design work has been completed, the building permit issued, and approval from the utility company received, it is now time to begin the installation. If the system is being installed on a roof the person performing the installation will need to be confident that they are able to make anywhere from 50 to over 300 roof attachment points (depending on the size of the system) without creating any leaks. Hopefully the chosen racking system utilizes flashings and rubber gaskets to ensure water tightness. If quality solar panels have been selected, they should be warrantied for 25 years. Therefore it is very important that whatever style of roof attachment is being used will be capable of remaining water tight for a minimum of 25 years. If the system is installed on the ground, heavy machinery will be required to secure the racking firmly and properly in place. Remember all work being done must be completed in accordance with designs approved by a licensed engineer, and will be inspected by the building department.
Once the racking is taken care of, the solar panels must be mounted. This is a fairly simple process, although wire management is vitally important. If wires running form the solar panels to the inverter(s) are not properly protected and secured the system may not pass inspection, and could potentially create a fire or electric shock hazard. If the system is installed on the roof there are very specific provisions in the National Electric Code (NEC) pertaining to wires carrying direct current (DC). Again if any of these provisions are not met, the system will not pass inspection and may need to be entirely redesigned.
The next step is to install the inverter(s). Assuming a string inverter has been selected, all the DC wires from the solar panels need to be properly terminated in the inverter. Whoever is performing this work will be dealing with live wires producing up to 600V in direct current. If these wires are not properly tested and terminated, they could potentially ruin an inverter worth several thousand dollars. If microinverters have been selected, the procedures for setting panels and performing wire management are completely different than they are for installing a system utilizing a string inverter. Once again proper: grounding, circuit size, wire size, conduit size, wire splicing and etc. are all paramount. The importance of attention to these details cannot be overemphasized. Not only is the overall production of the system at stake, but safety and code compliance are major concerns as well.
Next the inverter will need to be wired on the AC side. According to the NEC this phase of the installation can only be performed by a licensed master electrician. For anyone considering installing solar themselves, it is imperative that they factor in the cost of hiring an electrician to perform this work. It is also imperative that prior to reaching this phase of the installation, careful consideration has been given to where and how the PV system will be connected to the grid. Again there are dozens of potentially limiting factors that should have been addressed in the design phase of the installation. Complex upgrades to the service panel are not uncommon in terms of making the panel ready to accept solar backfeed. If this is the case, this work will also need to be performed by a licensed master electrician.
Now that the racking and modules have all been set, the wires run, the inverter installed, and the system connected to the grid, the system must be inspected. Depending on the stipulations set forth by the local AHJ, multiple inspections may be required both during and after the installation is complete. Additionally many inverters (string inverters and microinverters) come equipped with monitoring software. If this is the case, the monitoring system will need to be installed and configured with the home’s Wi-Fi network. Once this is complete and the utility company has installed a meter capable of reading the system’s power production (usually called a “Net Meter”) the installation is complete!
But wait! One thing often overlooked by do-it-yourselfers (and even some solar installers) is that utility companies often offer rebates and incentives to customers who install solar on their grid. Many utilities have different requirements for qualification, but in most cases a simple application is all that is required. If any rebates or incentives are overlooked, the system owner might be throwing away thousands of dollars in free money over the life of their system. Additionally there are important tax documents that need to be filed with the IRS for the system owner to receive their 30% federal tax credit.
So to answer the question of “can you install solar yourself?” the answer is yes – if you are willing to devote a large amount of time and effort to the project. The average person will need to do a tremendous amount of research before they are ready to begin the installation. Additionally they will need to be comfortable working on the roof (in the case of roof mount) or with heavy machinery (in the case of ground mount). They will need a basic to mid-range knowledge of construction, wiring, and electricity (as they pertain to solar). They will need to be willing to invest money in special tools, equipment rental, and hiring an electrician. Furthermore they will need at least one person who is willing to help them, as most phases of the project will require a minimum of two competent workers. So ultimately what the decision boils down to is a question of how much your time is worth to you. And are you willing to spend that time researching, planning, and installing all the components that go into a PV system? The final consideration is how confident you are in your ability to perform the installation at the same level of safety and quality that a professional solar contractor should be able to achieve. Ultimately, whatever you decide, you are making a great decision both financially and for the environment! So feel good… because you are doing the right thing!
Please check out our website at www.altewindandsolar.com and our Facebook page at www.facebook.com/Alt-E-Wind-Solar-Ltd-196202797091314/ or give us a call at 970-482-SOLAR(7652)
“Going Solar” is such an exciting decision! You already know you’re making a great financial investment decision as well as being a friend to the environment. So now you find yourself at the point where you contact different solar installers to get bids. A good installer should be able to give you a solid ball park price estimate over the phone if you provide them with your annual kilowatt usage and your address so they can look at a satellite image of you property on Google Earth. But to get an exact price quote, they will definitely have to make a site visit. So suppose you’ve received several quotes yet one is substantially lower than the others….how can this be?
This is where you have to be careful. It is tempting to go with the lowest bid, assuming that it will save you money. The old adage “If it sounds too good to be true, it probably is” definitely rings true here. It’s also true in this industry that you get what you pay for! Unfortunately there are companies out there who will provide you with erroneous or misleading information just to get your business; or will use shoddy product and cut corners on the installation… those companies likely won’t be around in the future should something go wrong with your system and you need help.
One of the most common ploys to be aware of is “Our solar panels are more efficient than others so they will produce more power.” This is very misleading. The efficiency of a solar panel has little to do with its power output. For example, a 300 watt solar panel is a 300 watt solar panel… it is only going to output 300 watts of power. Therefore 2 solar panels of the same size (wattage) exposed to sunlight for the same amount of time are generally going to produce the same amount of power (kilowatt hours). The efficiency has much more to do with the physical size of the solar panel itself… NOT how much power it will produce. If one 300 watt solar panel is more efficient than another 300 watt solar panel, that simply means it is smaller in physical size than the less efficient one. There are however some very small differences in solar panels that may contribute to one solar panel generating more or less power than another solar panel of the same wattage (i.e. – temperature coefficient) but these are small differences and will not greatly impact the power production, contrary to what many solar installers imply. The most important thing to remember here is that wattage is the most important consideration… a 10kW array is a 10kW array and one will not produce more than the other, regardless of solar panel efficiency. It is also important to ensure, that the installer is using Premium Grade solar panels from a Tier 1 manufacturer that offers a 25 year linear power production warranty. Also, ensure the solar panels have “re-insurance” to back up the warranty in case the manufacturer is not around if a warranty claim arises.
Another issue to be extremely aware of, if you are getting a roof mount system, is the type of racking that will be used to attach the solar panels to your roof. Many installers cut corners here in order provide you with a cheaper bid and win your business, but it is to your detriment. Roof mounted solar systems generally require attachments that penetrate the roofing material and attach to the roof joists or trusses in your attic. A reputable installer will use “flashing” which is a thin metal plate covering the roof attachment point, tucked under the shingle and further secured with bead of roofing tar AND silicon rubber gaskets to ensure no leaks ever occur at the penetration point for the full life of the system. A less reputable installer will just use something called an “L Foot” without flashing which is an L shaped bracket set and drilled into the trusses from the top of the shingle, leaving an opportunity for the roof to leak at every penetration point. Most will at least use a dab of silicon on top of the lag bolt that penetrates the roof, BUT… your solar panels have a 25 year warranty and I certainly wouldn’t want to rely on a dab of silicon on top of a bolt to protect my roof from leaking for 25 years or longer… would you? An installers cost for an attachment bracket WITH FLASHING and hardware is around $12 each versus an L Foot bracket at $2 each. Therefore, if you take a 10kW roof mount system, for example, it would require approximately 100 roof attachment points and 200 lag bolt penetrations into the roof (each roof attachment requires 2 lag bolts, if the installer is not cutting corners or using a low quality product). That means the cost to the installer is $1200 for the flashed attachment or $200 for the L Feet. It also is much less labor intensive to install an L Foot than it is to properly install a flashed attachment bracket. That one little trick right there allows the less reputable installer to knock approximately $1500 off your bid (parts & labor) with you being none the wiser……until your roof leaks.
Another trick commonly used by shoddy installers is to under size the inverter. It is really important to use an inverter that is large enough for your system to run at maximum efficiency. The inverter should not be sized less than 90% of the total size of the array (in kilowatts). The inverter can be slightly smaller than your array size because there are some system losses that occur (i.e. – panel soiling, wire/connection losses, etc.) but an inverter that is too small will “clip power” on a sunny day when the sun is over head. For example, if 10kW’s of solar panels are outputting 9kW’s of power but the system only has an 8kW inverter, then your system will only output 8kW’s because 8kW’s is the maximum output of the inverter. In this situation, your solar panels are producing 1kW (1000 watts) more power than the inverter can handle so the inverter “clips” the excess power (to avoid damage to the inverter), thereby wasting 1000 watts of electricity at that time. Obviously, the smaller the inverter is the less expensive it is so the installer can quote you a lower price and still tell you that you have a 10kW solar array, because you do in fact have 10kW’s of solar panels… even though it will not produce as much power as it should if the inverter were properly sized.
One final thing to be aware of… ask your installer to justify their power production calculations and make sure that all the quotes you receive use the exact same “system loss” calculations. Many installers will misrepresent the system losses, which produces the illusion that their solar array will produce more power than the other more reputable installers. I’ve even seen several installers say “because our system produces more power than our competitors (for whatever bogus reason), we can build a smaller system for you, which in turn saves you money on the installation cost.” Again, total hogwash! Bottom line is… a 10kW array is generally going produce the same amount of power as another 10kW array, if it’s properly designed and installed! So make sure they not only provide you with the power production calculations but ALSO with their “system loss” calculations so you can verify that all installers are using the same accurate calculations and that someone is not misleading you here.
It is so important to have an excellent installer when it comes to your new solar system. The best way to find them is to ask questions. An installer worth his/her salt should take plenty of time to answer any question you have down to the very last detail…..as you can see, details are important. Also, ask for references! These customers can give you feedback on the installation process, the efficiency of their system and if any problems arose, how they were dealt with. They are the best way to make sure the installation company has stood the test of time. Many companies can slap together a cheap installation but the few really good ones will provide an excellent product, outstanding service and be there for you down the road when and if you need them. Going with a reputable installer may cost a little more up front but is surely worth your peace of mind.
Please check out our website at www.altewindandsolar.com and our Facebook page at http://www.facebook.com/pages/Alt-E-Wind-Solar-Ltd/196202797091314 or give us a call at 970.482.SOLAR (7652).
Well, it looks like the New Year is well under way because, believe it or not, February is almost over! Here at Alt E Wind & Solar the phones have been ringing off the hook since many incentives offered by utility companies have renewed. One of the things we love best about our jobs here is the opportunity to educate our prospective clients about everything involved in “going solar” so they are well equipped to make the decision that best suits their needs and, therefore, successfully fulfill their goals. In the process of fielding all these calls with so many great questions, we have come to see a general pattern in the things that people tend to ask, or want to discuss as they are getting started with the process. Below is a list of things to ask yourself, or consider if you are seriously thinking about taking the plunge. Once you have a handle on these preliminary questions and topics, then it will be easy to get the ball rolling!
- Are you looking to fully eliminate your electricity bill or just offset it?
- What is the last 12 months of kWh (kilowatt-hour) usage for your home? You have to get this information from the last 12 months of your electric bill or simply call your utility service provider.
- What is your budget? Financing can be an option.
- Does your roof have good southern exposure?
- Do you have any open land for a ground mount system if your roof is not optimal?
- Do you have a lot of mature trees that may obstruct the sun? Shade is the enemy of optimally functioning solar panels.
- What incentives or rebates does your utility company offer? If you forgot to ask them this question when you had them on the phone, don’t worry, Alt E has a great handle on most utility programs and can answer that question when you call.
- Did you know the Federal government will provide a 30% tax credit for the cost of you solar system? This is a dollar for dollar reduction to your Federal tax liability, which means that the IRS essentially pays for 30% of your solar system!
- Did you know 95% of today’s solar systems are tied to the electric grid? Alt E, however, can design either an off grid OR hybrid system with battery backup. Both of these are a more expensive option but new technology coming in the near future promises to bring these prices down.
- Important to know that your installation company should take care of all necessary design requirements, engineering and permitting requirements as well as all required electric utility paperwork.
- Did you know the state of Colorado prohibits homeowner’s associations from restricting the installation of solar panels? CLICK HERE if you would like to review the state statute.
- Did you know solar panels can withstand high winds and hail very well and also come with a 25 year warranty?
- Were you aware that solar panels require little to no maintenance?
- And….last but not least, a new solar system will generate a risk free, average annual return on investment of 10-20% over the lifetime of the system!
Again, these are just preliminary questions and topics but doing some research and finding more in-depth information will help a great deal in making your decision and then moving forward. We would, however, love to hear from you should you have any more questions or would like general pricing information over the phone. Should you have further interest, the next step would be for us to set up a sight analysis and then put together a proposal with all the specific information you would need in order to get the job done. We are always here to help so please, don’t hesitate to give us a call today and see what we can do for you!
Please check out our website at www.altewindandsolar.com and our Facebook page at http://www.facebook.com/pages/Alt-E-Wind-Solar-Ltd/196202797091314 or give us a call at 970.482.SOLAR (7652).
HOW MUCH WILL IT COST TO INSTALL SOLAR ELECTRIC (PV) IF MY GOAL IS TO ELIMINATE MY ELECTRIC BILL (“NET ZERO”)?
If your goal is to eliminate your electric bill then the next several questions to be answered are: what was your last 12 months of kWh (kilowatt-hours) usage? Was that a typical year or were there things that caused your electric usage to differ from your normal/current usage? Do you have enough shade free roof space with southern exposure? If your roof is not well suited then do you have shade free space on your property for a ground mount system?
When calculating your last 12 months of kWh’s used, you can either: 1) pull out your utilities bills for the last 12 months and look for the total kWh’s consumed per month and then add up the last 12 months; or 2) simply call your utility company, give them your account number and they will give you the month by month breakdown for the past year. It is important to note that for a grid-tied solar system, neither the peak monthly usage nor the average monthly usage are nearly as important as the total annual usage.
After you have determined the past 12 months kWh usage, the next question to be answered is was that a typical year of electric consumption or will there be any change in your electric usage in the future? Maybe you were out of town a lot more than usual, in which case you used less electricity than normal. Maybe you’re planning to build an addition on your home or build a workshop. Or maybe there will be more or less people living in your home going forward. If any of these things are the case then we can adjust the size of your solar array to ensure you achieve your “net zero” goal.
The next thing you’ll want to ask yourself is do you have good shade-free southern exposure on your roof? If not, do you have shade-free space on your property for a ground mounted solar array? Another thing to consider is the tilt and orientation of your roof, as these two things can dramatically impact how much power (electricity) your system will produce. With a ground mount array, we can build the solar array to be 100% optimal. Don’t worry too much initially about the location… we have shading analysis tools and can ultimately help determine the best location for your solar array. The main things to consider here are your location preferences and options; but remember – shade is the enemy!
Once the above questions are addressed then we can determine what size your solar system needs to be in order to eliminate your electric bill. As a very broad based rule of thumb, each kW of solar panels installed in Colorado will generate around 1,300 – 1,600 kWh’s annually, depending on the tilt and orientation of the solar panels (this is a topic which will be discussed in future blog posts).
There are many variables in determining the cost of installing solar on your home or business. But one of the most important things to understand is that solar pricing is not linear. Generally speaking, the larger the system is the lower the cost (per watt) will be. A 10kW (10,000 watts) solar system will cost a lot less per watt than a 4kW (4,000 watts) system. Of course, the total cost of a 10kW system will be higher than a 4kW system but the larger the system is the lower the cost per watt and the greater the return on investment.
Many solar installers will tell you that a ground mounted solar array will cost a lot more than a roof mounted array. This is not necessarily the case! With a roof mounted array we are limited by the tilt and orientation of your roof, which in most cases is less than optimal. Therefore, in order to produce the same amount of electricity, a roof mounted solar array must be larger than that of a ground mounted array, which can be built to be 100% optimally oriented. Let’s say the tilt and orientation of your roof are such that you’ll only achieve 90% of the optimal power production. If that were the case (very common) then a roof mounted solar array would need to be approximately 10% larger than a ground mount array in order to achieve the same power production. In this situation, a ground mounted solar array would be less expensive than a roof mounted array.
There are many other variables that impact the cost of installing solar, which we evaluate during our site analysis (ie – breaker panel and electric service, roof structure and material, rafter/truss system, meter location, point of grid interconnection, conduit runs, etc.). However, getting to the heart of the question, the total turn-key cost of having solar installed on your home or business will typically be between $3.50/watt, for larger solar PV systems, and upwards of $6.50/watt for smaller systems. In addition, everyone who installs solar on their home or business is eligible for a 30% federal tax credit (this is not a tax deduction; it is a tax credit… a dollar for dollar reduction in the taxes you pay to Uncle Sam), thereby reducing your installed cost by 30%. Also, many utilities offer rebates and/or REC (Renewable Energy Credit) payments based on the size of the solar system and the amount of power it produces. These utility rebates can also drastically reduce the cost of installing solar. Please call us at 970.482.SOLAR (7652) if you want to find out what rebates your specific utility offers.
Please stay tuned next Thursday for Part 2: “Putting it all Together”! Here we will use an example addressing everything we’ve discussed in this post. In the meantime, please check out our website at www.altewindandsolar.com and our Facebook page at http://www.facebook.com/pages/Alt-E-Wind-Solar-Ltd/196202797091314 or give us a call at 970.482.SOLAR (7652).
HOW MUCH WILL IT COST TO INSTALL SOLAR ELECTRIC (PV) ON MY HOME OR BUSINESS?
The answer to this question is not as simple as is seems. There are many variables starting with your goals and desires. The first question to ask yourself is what kind of solar photovoltaic (PV) system do you want? There are three primary types of solar PV systems (the kind that generate electricity).
The first type of solar PV is what we call a grid-tie or grid-connected system. This is by far the most common and least expensive. Your solar system is connected directly to the grid so your meter actually turns backward when your system is producing more power than you are consuming and turns forward when you are using more electricity than the system is producing. At the end of the month the utility company only bills you for the “net” amount of electricity used. If your system produced more electricity than you used during the month then you can elect to have the utility pay you for that excess power or have it collect in your “solar bank” to be used at a later date. This type of system is pretty much maintenance free (solar panels have a 25 year warranty) and there is no need for batteries since the grid provides power to your home or business when the sun isn’t shining.
The second type of solar PV is an off-grid system. This type of system is used primarily for homes where grid power is not available or in situations where you simply don’t want the utility to provide your power. These types of systems require a battery bank and can get pretty expensive depending on your electric loads (how much power you will need). Basically the batteries provide all your power and the solar panels keep your batteries charged. Therefore the more power you use the larger the battery bank (and solar array) will need to be. These systems can get pretty expensive over time because the batteries need to be replaced about every 6-8 years, if properly maintained.
The third type of solar PV is a hybrid system. This is usually a grid-tie system with a battery backup and is used by those who are concerned with power outages or grid failure. These are by far the most expensive since we are creating a “smart” system to determine where the power is coming from (solar, grid, batteries, generator, wind turbine, etc.) and where it is going to (your electric loads, to charge the batteries, or fed back into the grid). These types of systems have several additional components and unique requirements that are not necessary with the other types of solar PV systems. The primary advantage to these types of systems is that you are able to have power even if the grid goes down. However, the primary disadvantage is the upfront cost and maintenance expense.
Since 95% of all solar PV systems being installed today are grid-tied, we will begin by first answering the “what does it cost” question for this type of system. We typically take one of three different approaches to designing a grid-tie system depending on what your goals and objectives are:
- The first approach is to design a system to eliminate your electric bill;
- The second approach is to design a system to maximize your roof space;
- And the third approach is to design as large of a solar system as we can within your budget.
We will discuss each of these three approaches in our next three blog posts… so stay tuned!! In the meantime, please check out our website at www.altewindandsolar.com and our Facebook page at http://www.facebook.com/pages/Alt-E-Wind-Solar-Ltd/196202797091314 or give us a call at 970.482.SOLAR (7652).