So, you’ve heard a lot about solar energy but you’re still not quite sure how it works. Understanding the intricacies of solar is helpful in knowing why you should go green. We’ve taken the liberty to break down some of homeowners’ most pressing questions about solar energy, from the components of a typical solar installation, to how you can get paid for the energy your system produces.
There are several components that go into building a solar system. The most basic elements include mounts and flashing, racking/railing, conduits and wiring, solar panels, and inverters.
Mounts are secured onto the surface of the install site, typically a roof, as a foundation for the system. Aluminum flashing, used to stop water from leaking into the roof, is installed by lifting the shingles and inserting the flashing underneath them. Racking is fastened on top of the mounts where they will secure the panels. Next, solar panels are attached, with adequate support from the racking and mounts. Wiring is then run throughout the panels to power the solar system. RevoluSun completes the system wiring from inside the home (typically in an attic or crawl space), to ensure no ugly wires or conduits are visible whatsoever. In most cases, conduits are provided to house the wiring to ensure the wires can safely run from the system down into the main service panel. Lastly, solar inverter(s) are installed on the outside or inside of the home, typically in the garage or basement. The solar inverter is responsible for converting the energy produced from direct current (DC) to alternating current (AC) that can be used as electricity in your home.
What are solar panels made of?
Solar panels contain a number of elements that allow them to harness the sun’s energy. These materials include silicon solar cells, metal frames, a glass sheet for casing, standard wiring, bus wires, and plexiglass. Plexiglass is used as an extra precaution to protect the solar cells. In order to maintain efficiency, an insulation sheet is installed to keep the solar cells cool and reduce humidity within the panel. The cooler the panel, the quicker it can process sunlight into energy. Like all electronics, solar works slightly more efficiently in cooler climates.
Three types of solar panels
Despite the fact that many panels include the same components, there are still different types of panels. Currently, there are three types of solar panels on the market: amorphous, monocrystalline, and polycrystalline.
Amorphous panels are the cheaper and less efficient modules within the industry, made of silicone and steel. Polycrystalline solar panels are easily identifiable by their noticeable blue coloring. These panels are much more efficient than amorphous panels but require more space than monocrystalline panels. Due to their higher silicon purity, monocrystalline panels are more efficient than the others. Thus, monocrystalline panels have become the most popular choice, as they are extremely efficient and take up the least amount of roof space.
Manufacturing solar panels versus burning fossil fuels
Some people believe that the manufacturing of panels is bad for the environment, but it’s not even a fraction of the impact of burning fossil fuels. Although some greenhouse gasses are emitted into the atmosphere during the production of solar panels, it is less detrimental to the environment than using other energy sources, such as coal and gas. Fossil fuel extraction and consumption is responsible for a major portion of all greenhouse gas emissions. Specifically, fossil fuels produce 100 grams of CO2-equivalents per kWh of electricity formed, while solar power only emits 10 grams of CO2 per kWh, meaning fossil fuels yield at least ten times more CO2 than solar panels. Plus, once they are assembled there are no hazardous emissions, unlike the processes involved with extracting and burning fossil fuels.
How do panels generate electricity?
A whole solar system is able to capture the sun’s rays and turn them into usable electricity for your home.
First, sunlight radiates photons, which are invisible energy molecules. These photons are then absorbed by conductive layers that house electrons. The photons then collide with the electrons, knocking them free of their atoms. Next, these electrons move through the conductive coating and enter the solar cell. Then, when positive and negative sides of a cell interact, they form an electrical current. When the electrons move throughout this circuit, they begin to produce electricity. This movement of electrons happens in each cell and there are several cells that make up each panel. Multiple panels circuited together, create a solar array. Thus, the more panels, the more cells, meaning the more electricity for your home.
The solar inverter then takes DC electricity and turns it into AC electricity that can power your home. Solar inverters are essential in turning solar energy into electricity. Their largest task is to convert direct current, that has been produced by the solar panel, into alternating current, which can then be used to power your home. RevoluSun primarily uses the SolarEdge Single Phase Inverter. However, SunPower AC panels include an Enphase microinverter on the back of each panel that acts as a SolarEdge inverter would, eliminating the need for a standard inverter.
Saving money is the largest motivating factor for those looking to install solar panels. A big part of saving money with solar is the ability to bank excess energy your solar system produces back to the electric grid. Throughout the day, your solar system is producing energy. This electricity is automatically stored in your utilities’ electrical grid in the form of solar credits. Each time you use electricity in your home, you utilize those credits and apply them to your electric bill. Ideally, your system will produce enough power in the spring and summer months to provide enough credit to eliminate your bill in the winter months.
When your solar system generates extra solar energy, your utility grid will provide an on-bill credit. This process is referred to as net metering. How much your utility company will pay for your unused solar credits depends on your utility company and the state you live in. In Massachusetts, utilities provide credit remarkably close to the electric retail rate.
Richie Bonney, our Vice President of Project Development, went solar over a year ago and is experiencing tremendous savings. Richie’s system produces enough energy every month to sell back to the grid and offset his entire electric bill (right). Solar panel ownership allows the relationship between utilities and customers to flip so that the utility company credits solar customers for their energy instead of the customer purchasing energy from the utility. National Grid owes Richie $254.10 for the excess energy that was automatically sent back to the grid.
In addition to net metering, the Massachusetts Department of Energy Resources (DOER) has unveiled the Solar Massachusetts Renewable Target (SMART) program. The SMART program allows solar owners to receive money, in addition to their electric bill credit, for their solar production at a set kilowatt-hour rate. SMART is a declining block system. Once Block 1 fills up, solar customers will be enrolled in SMART’s second block and so on. There is a 4% loss in incentives as you move down the blocks, estimating that the average customer who doesn’t get into Block 1 will lose an estimated 8-10% in savings. Currently, National Grid customers will receive around $0.11 per kWh of electricity produced, while Eversource clients collect about $0.14 per kWh. Those enrolled in SMART will receive a monthly check with their solar incentives.
How do solar panels save me money?
There are many components to solar that help saves money, besides just selling excess solar energy back to the grid. This includes a federal tax credit, increased property value, and decreased electricity bills.
Last chance for the 30% Federal tax credit
Currently, U.S. residents are entitled to a 30% tax credit on the amount they pay to own a solar system. Renewed in 2015 by Congress, this tax credit has allowed countless U.S. residents to go solar. Yet, this tax credit might not be in effect for much longer. The current administration does not advocate for the tax credit and is seeking ways to cut down spending on renewables. This makes solar a pressing issue as time may be running out on large incentives. This year, 2019, is the last year that customers can take advantage of the 30% Federal tax credit. It is imperative to go solar before the tax credit expires since it is partly responsible for solar customers’ rather quick return on investments.
Make your home smarter
Unlike other home improvement projects, solar systems add value to your property without tacking on an additional property tax. This makes your home more valuable if you ever decide to sell. Buyers are willing to pay an additional $15,000 for a home with the average-size solar system, compared to a similar home without a solar system. A low or non-existent electric bill is attractive to buyers. In a challenging market, solar panels can be the difference in selling your house or not, an added bonus that gives potential buyers a reason to consider your house over others as their next long-term home.
By going solar, homeowners save thousands on their electric bills. Solar customers are no longer at the mercy of the utility companies escalating prices. Electricity rates rise every year, but with solar energy, customers are no longer affected by these rising rate costs because they’re producing their own energy.
In addition to solar savings, there are many affordable options when it comes to financing your solar system and investment.