When you think of solar power, what kind of technology do you imagine? Would you be surprised to learn that there are many different methods of harnessing solar energy, such as: water-heating solar, passive solar, solar-heated windows, and concentrating solar?
For our purposes, whenever we refer to solar in this blog or on the McClintock site it is purely in the context of the photovoltaic (PV) solar panels that generate electricity from sunlight as an alternative to the traditional electric utility with which you may be most familiar.
That said, let’s answer that most basic of questions: What is a PV solar panel?
A PV solar panel is made up of around 60 square, solar sensitive, wafer-thin silicone segments known as cells that are fitted together into a large panel about the size of a picnic tabletop, all framed in aluminum and protected by tempered glass. These cells absorb the rays of sunlight, also referred to as solar energy. Solar energy isn’t only defined as the light you can see, but also the spectrums of light you can’t, like UV light. Through an interaction of photons and electrons, the cells in a panel convert solar energy into direct current (DC) electricity, the most volatile kind. Solar panels also have what are called junction boxes that allow them to be interconnected into a system of panels called a solar array.
There are different kinds of solar panels you can buy depending on the longevity, power, and capital expense you’re anticipating.
Thin film panels are the figurative push scooters of the solar panel world compared to the ultra-high performance of concentrated PV panels, which can reach much greater efficiency. Thin film panels are often manufactured to be flexible, and are much lighter weight than their silicone counterparts, although their counterparts are more efficient and more powerful, albeit more expensive to purchase and install. They can be made with four (4) different material technologies, all varying in strength and efficiency. Whichever you prefer depends on what products are available in your area, and your capital expense.
The cells of poly-crystalline panels are manufactured when many different fragments of silicone are melted together to form a bar that is shaved into wafers. Poly-crystalline panels are moderately efficient when it comes to energy creation, about 15%, but they are also moderately expensive. They aren't flexible, come in a light or dark bluish hue, and have a slightly lower life span than their single crystal counterparts. Poly-crystalline panels are one of the most common types for their affordability while also performing to adequate, lasting standards. Think: Cadillac, and you're pretty much there.
Finally, if you’re looking for efficiency regardless of cost, you’ll want to go with mono-crystalline solar panels, the figurative Ferrari of the three listed options, and which can reach 20% efficiency or more. Mono-crystalline panels have a black appearance and cells that are created when a single piece of silicone is formed into bars and shaved into wafers. Like their multi-crystal siblings, they're not flexible like thin film panels because they're framed in aluminum and protected by tempered glass, and because these cells are manufactured with single-crystal material they conduct electricity much more efficiently, resulting in better performance for your buck and a better long-term output.
Now that you know the difference between different PV panels, their construction, and pricing, which panel would you choose for your home?
As stated in The Basics, the junction boxes on each solar panel allow them to be interconnected into what is called a solar array. Solar arrays can be installed on your roof or in your yard to collect enough energy from sunlight to allow you to power your home or business on or off the traditional energy grid. Let's take a look at different mounting options for your solar array to determine which may be the best for you!
Ground Mounted Array
There are several benefits and drawbacks to ground mounted solar arrays. First, you don’t want to consider a ground mounted array if you don’t have a lot of space. Ground mounted arrays take up considerable stretches of land depending on how much energy you need to generate.
Also, the upkeep of ground mounted systems offers both pros and cons. One pro is that in the winter, ground mounted systems don’t require you to scale a rooftop to knock snow and debris off of your array in order to keep the panels capturing optimum light. Nor when it is time to clean your panels does cleaning require ladders, pulleys, or safety gear sometimes necessary with rooftop arrays.
Even though you do have to mow around the ground mounted panels and be sure that animals, inclement weather like sleet and hail, and low-flying debris don’t damage them, the accessibility of ground mounting makes up for any inconvenience of losing your horizontal space. Ground mounted arrays also tend to be preferable for the 30-40-degree tilt that is ideal for catching sunlight. There are also automated options with ground-mounting that will tilt the panels in the direction of the sun as it moves throughout the day so that your array gets the best access to solar energy from dawn until dusk.
Roof Mounted Array
Don’t have the space to ground mount your array? That makes your decision easier. Here is some further important information for your reflection.
For those of you who still have to consider your options, these are a few elements to be noted if you want to make an informed decision.
- Sunlight your region receives
- Shading around your home (trees, other buildings)
- Cardinal Direction your roof/property faces (S is best, N is least ideal)
- Tilt/Angle of your roof
- Age/Condition of your roof/home
Choosing a rooftop array may require that the installer penetrate the surface of your roof in order to install the mounting that the panels will rest upon, so knowing that the installer you use is licensed and insured is an important factor in following through with this decision. All McClintock installers are fully licensed and insured, and 100% prepared to safely and competently install your solar array!
The methods of installation may vary depending on the type of roof you have, its condition, and tilt. Methods of installation include:
Flashing – panels can be mounted under the shingle, and a flashing cover lays over top of it to prevent potential leaks;
Ballast – no roof penetration; solar array is weighted down as opposed to fixed;
Stand-offs & Beams – running beams across spans that can’t support the weight of fixed or weighted arrays;
Clamps – clamp onto a standing seam roof;
Pitch Pockets – stainless steel sleeve that penetrates the roof and is sealed into place with sealant to prevent leaks; NOT permanently leakproof; Requires yearly maintenance;
Other installation methods may vary depending on the unique design of your home. All research and consideration methods are encouraged before coming to a decision about what method is best for your installation.
To speak to a McClintock Electric installation specialist about a FREE assessment of your home, and to discuss installation methods that may be appropriate for you, click on this link!
Not ready to get a free estimate? Fair enough. Let’s kick it up a notch and take you to Solar U.
You have the basics of the panels:
The cells, which are good, better, or best depending on the material and/or crystal quality of the material, absorb solar energy and convert it into the kind of jolt that roasted good ol’ Uncle Ben on his famous kite-flying excursion. DC electricity—direct current.
Direct current electricity made Thomas Edison a household name. While DC power allowed people to have indoor lights, fans, appliances, and lives closer to what we know as modern, it was also so unpredictable to control that power surges were common. Consequently, electrocutions and electricity fires would follow, shocking (no pun intended) a terrified public growing ever more reliant on electricity to function.
Enter Nikola Tesla, and alternating current (AC) technology. Alternating current technology controls the surge of the electric current as it travels, preventing it from overloading like direct current is prone to do. Alternating current is what we use on many of our devices, in many of our homes, and in order for us to be able to use the DC power generated from the cells of solar panels, we need to convert it to AC before trying to draw on it as we would when plugging in a toaster.
That begins with the junction boxes on each solar panel, and whether you swear by optimizers with a standard inverter, or micro-inverters.
PV Panel Junction Box
(image credit: WikiMedia Commons)
These two (2) basic ways the energy collected from your solar array can be converted to usable AC electricity operate as follows:
1) Power Optimizers w/ Standard Inverter - The DC electricity is pushed through a device called an optimizer installed on each panel’s junction box, and then sent from the solar array via cable into an inverter box, which is located in a dry area of your home, such as a basement or garage, and ideally near your electric box. Once the DC energy is converted to AC, it is pushed into your electric box where your home draws on it for power.
(SolarEdge Inverter & Power Optimizers)
2) Micro-inverters - A device called a micro-inverter is installed on the junction box of each solar panel, which allows the DC energy to be converted to AC right where the panel is installed without being transferred to an inverter box. Once converted to AC, the electricity is sent via cable directly to your electric box where it is drawn on for power.
The benefit of either conversion system depends on your preference, and your needs. Both optimizers and micro-inverters allow for the monitoring of individual panels within an array, and maximize the performance of panels that receive some shade. Many brands of optimizers and micro-inverters also come with up to 25-year warranties upon purchase, although the standard inverter only comes with a 5-12 year warranty. That’s not to say that it will only last for 5-12 years, but the warranty may only cover that amount of time.
That said, if you choose to go with micro-inverters, remember that you’ll need to buy one for every new panel you add to your array in the future. Albeit, you won’t have an inverter to maintain and/or replace despite that the cost of each micro-inverter will be more than the cost of each optimizer. And if one micro-inverter malfunctions it doesn’t affect the entire array, whereas if your standard inverter malfunctions, your entire array is affected.
So there are benefits and drawbacks of both optimizers with a standard inverter, and micro-inverters. What you decide to do then is contingent on your needs, your preferences, and your budget.
More questions to ask yourself: How powerful should my system be? Depending on the panels I choose, how many do I need to power my home adequately?
The power of solar systems is measured in kilowatts (kW) and how much power you need is determined by the number of kilowatt hours (kWh) your system produces. A kilowatt is a unit of watts (W), which is a measurement of electric energy named after James Watt, an 18th century Scottish inventor.
In simple terms, a watt, and by extension a kilowatt, measures the rate of energy transfer in an appliance. Watts can be measured in joules (J), a smaller measure of electric energy. Each watt changes one (1) joule of electricity into light energy per each one (1) second increment, and it takes 1000 watts to make one (1) kilowatt.
The power, and subsequently the size of your system will vary from home to home. If you have a larger country home, you’ll want a more powerful system. If you have a mobile home then you won’t have as much room to install your array in addition to not needing as much power as, say, a standard ranch home. Whatever the size of your space, the amount of power you may need can be estimated by looking at your electric bills and calculating the amount of kW you’re using compared to how many you could be producing with a solar-powered system.
According to the U.S. Energy Information Administration, the average home in 2018 uses around 1,000 kWh of electricity per month.
Most homeowners, therefore, install from 2kW – 12kW systems, covering 20%-80% of their energy needs. These systems can be expanded upon in many cases and upgraded to be more cost efficient as newer technology becomes available.
To put this into fiscal terms, in 2020 a 7kW system costs around $22,300 before the 26% Solar Investment Tax Credit (ITC), and around $16,500 after the Solar ITC. Generally speaking with all considerations involved, most systems pay for themselves within 5-7 years.
Assuming you fall into the category of solar owner whose system pays itself off in seven (7) years, that means that you could be saving $2357/year in electric bills with the money saved put towards paying off your solar system and not taken out of your pocket!
To Lease or To Buy?
Here’s where the money-saving can get tricky:
If you lease your panels, you can’t write them off as a tax credit since you don’t own them, nor can you rack up utility credits with your local electric company—also called net metering—and while you’re missing out on federal tax incentives, you may also be missing out on yearly local tax incentives.
Leasing companies exist to ensure that their profit margins remain, well…profitable. They are said to try and sell customers more panels than they need, and push customers to install panels in unsightly places without regard for optics if it means maximizing their output.
If you lease solar panels and later decide to sell your home, that will present another difficulty to overcome. In order to exit your lease you must either buy it out, or ensure that the new homeowner will take it over for you. Some leasing providers will provide relocation services and move your panels, but not all providers will do this.
One way or another, it's important to remember that whether leasing or buying, insuring your solar system adequately is always a smart idea. Since many of the parts already come under warranty, damages to the system may already be covered, but you can never be too safe when protecting a valued investment! Check with your warranty provider about what types of situations may not be covered by their warranty program to know if purchasing solar insurance is right for you!
To Buy or To Rent?
Here's another great aspect of going solar: when it's time to sell your home or property, the state and federal tax incentives offered make any home equipped with solar systems instantly at the top of any home shopper's list! Renter's don't get that same reward.
The state of Ohio offers a loan interest reduction for homes that go solar, as explained on the state of Ohio Treasurer's website:
There are no fees assessed by the Treasurer’s office for the preparation, processing, reporting or monitoring of any ECO-Link application. The application process is simple and easy to complete."
If you need to get a loan to pay for a new solar system, the 3% loan interest reduction + the 26% Solar ITC + the savings from the monthly electric bills will go a long way in helping the solar system to pay for itself!
Do you want to see how much you can save from going solar? Click on the button below and consult with a McClintock Solar Specialist today!