Solar Terms
Solar Energy Terms: A Begginer's Guide
From savings to sustainability, we’ve put together a list of must-know keywords to help you get started on your solar journey
Photovoltaics (PV)
Photovoltaics are the process by which sunlight is converted into electricity. When sunlight (specifically photons) hits the silicon in a solar panel, it transfers its energy to the electrons in the silicon atoms. This light energy “knocks” electrons loose, allowing them to flow freely. The silicon is structured in such a way (with a positive and negative layer) that the freed electrons naturally move in a single direction, creating an electric current.
Solar Inverter
Think of your solar panels as speaking one language (DC electricity), but your home speaks another language (AC electricity). The inverter is the translator for your home, deciphering the DC electricity your panels produce into AC electricity you home can use.
Inverters also play a key role in monitoring system performance. Many modern inverters come with apps or tools that let you see how much energy your system is producing in real-time.
Power Purchase Agreement (PPA)
A Power Purchase Agreement (PPA) is a hassle-free way to enjoy the benefits of solar without the upfront costs or responsibility of owning the system. Here’s how it works:
At ARC, we install and own the solar panels on your property, covering all the costs of installation and maintenance. You don’t pay for the system itself—you simply agree to purchase the electricity it generates at a lower rate than your utility company charges.
Investment Tax Credit (ITC)
The Investment Tax Credit (ITC) is one of the most significant incentives available for going solar, offering homeowners and businesses a direct way to reduce the cost of installation. The ITC allows you to deduct 30% of the cost of your solar system from your federal taxes. This applies to everything from the panels and inverters to installation costs.
For example, if your solar system would cost $20,000, you can claim $6,000 as a tax credit, directly reducing what you owe the federal government. Both residential and commercial consumers across the United States can take advantage of the ITC.
Net Metering
Net metering is a billing system that allows solar panel owners to send excess electricity back to the grid and earn credits for it. When your solar panels produce more energy than your home uses (like on a sunny afternoon), the extra power flows into the utility grid. In return, your utility company gives you credits that reduce your energy bill.
When your panels aren’t producing enough energy—like at night or on cloudy days—you can use those credits to offset the cost of pulling energy from the grid.
REAP Grants
The Rural Energy for America Program (REAP) helps farmers and rural businesses cut energy costs by providing grants that cover up to 50% of renewable energy project costs. Paired with loan guarantees, REAP can fund up to 75% of a project. When combined with tax credits and other incentives, it makes solar far more accessible for rural communities. And here’s the best part: once your system is paid off, all the energy it generates goes straight to offsetting your annual costs, boosting your bottom line.
For Illinois residents, this program offers affordable solar with no upfront costs, and guaranteed consumer protection. This program is designed to support income-eligible households, nonprofits, and public facilities. ILSFA ensures that renewable energy is accessible and can help those that need it most.
Renewable Energy Credits (RECs)
Think of Renewable Energy Credits (RECs) as proof that your solar system is actively supporting a greener planet. Under the Illinois Solar for All (ILSFA) program, the state purchases RECs from approved solar vendors, providing upfront payments for 15 years’ worth of renewable energy production.
Here’s how it works: these upfront REC payments incentivize solar companies to install systems at no upfront cost to the homeowner or organization. For every megawatt-hour your panels produce, a credit is earned, ensuring the state meets its renewable energy goals while making solar accessible to those who need it most. This system not only drives clean energy adoption but also removes financial barriers for participants.
Solar Battery Storage
Traditional solar systems provide energy when the sun is shining, but what happens at night or on cloudy days? That’s where solar battery storage comes in.
With a battery, your system stores any excess energy your panels produce during the day. Instead of sending all that extra power back to the grid, it’s saved for when your panels aren’t producing—like at night or during an outage. This gives you more control over your energy use, reduces reliance on the grid, and ensures your home stays powered no matter the time of day.
Battery storage turns solar into a 24/7 energy solution.
Solar System Efficiency
Efficiency in solar works like miles per gallon in a car—it’s all about getting the most energy from the sunlight that hits your panels. The higher the efficiency, the more power your system can generate with the same amount of sunlight.
However, not every home is ideally suited for solar, and certain factors can limit how efficient a system will be:
- Roof Orientation: Solar panels perform best on south-facing roofs. If your roof faces east or west, efficiency may decrease.
- Shading: Trees, nearby buildings, or chimneys that cast shade over your panels can significantly reduce energy production.
- Roof Angle: Steep or flat roofs can affect how well panels capture sunlight throughout the day.
- Weather Conditions: Areas with frequent cloud cover or snow may reduce the overall energy your system can produce annually.
These factors don’t make solar impossible, but they can affect whether it’s the right fit for your home. Efficiency matters, and understanding these challenges upfront can help set realistic expectations for what a solar system might deliver.
Agrivoltaics is an innovative approach to renewable energy that combines solar power production with agricultural practices. Instead of using land solely for farming or solar panels, agrivoltaics integrates both, allowing crops, livestock, or even pollinators to coexist with solar energy systems.
With increasing demands for renewable energy and land use efficiency, agrivoltaics is gaining attention as a dual-use solution. Farmers can maintain agricultural output while generating clean energy, making the most of every acre. It’s a win-win solution for farmers and landowners, you can produce your own energy, reduce annual costs, and still utilize the space where the panels are installed.
Net Zero
A net zero home or building produces as much energy as it consumes over the course of a year, effectively balancing its energy usage with renewable energy production. By achieving net zero, you’re not just saving energy; you’re leading the way toward a more sustainable future.
Grid-Tied vs Off-Grid
A Grid tied solar system connects to the utility grid for backup energy. Excess power you produce can also be sold back to the grid. On the other hand, off-grid systems are completely independent, these systems rely on panels and batteries and a perfect for remote locations – or those who want total control.
Monocrystalline vs. Polycrystalline Panels
Solar panels come in two main types: monocrystalline and polycrystalline. Both are made from silicon and serve the same purpose – converting sunlight into electricity – but they differ in efficiency, cost, and appearance with Monocrystalline panels typically appearing black and made from a single, pure silicon crystal. Whereas Polycrystalline panels are typically the more affordable, lower quality option.
Community Solar
Community solar allows individuals, businesses, or organizations to benefit from solar energy without installing panels on their property. Instead, participants subscribe to a portion of the energy produced by a nearby solar farm. It’s like joining a shared garden, but instead of fresh produce, you get clean, renewable electricity.
Solar EV Chargers
Powering your electric vehicle (EV) has never been more accessible. With solar energy, you can install an EV charger that’s directly tied into your solar panels, allowing you to charge your car with the clean, renewable energy your system produces.
Prefer flexibility? EV chargers can also be connected to your home’s power or tied into the grid, ensuring you always have options for charging. But when paired with solar, you reduce reliance on the grid, save on energy costs, and drive with the confidence that your car is powered by the sun.
Solar Racking System
Solar racking refers to the structures that hold your solar panels in place, whether they’re mounted on your roof or installed on the ground. These systems are designed to position the panels at the optimal angle to capture sunlight efficiently while withstanding wind, snow, and other environmental factors. High-quality racking ensures your solar system’s durability and performance over time.
Microinverters
Unlike traditional inverters that convert electricity for all panels at once, microinverters are installed on each individual solar panel. This allows for better performance monitoring and ensures that shading or damage to one panel doesn’t reduce the efficiency of the entire system. Microinverters are especially useful for roofs with partial shading or complex designs.
Solar Canopies
A solar canopy is a raised structure that supports solar panels, typically installed over parking lots, walkways, or open spaces. Solar canopies serve dual purposes: generating renewable energy while providing shade or shelter underneath. They’re a popular choice for businesses, schools, and even residential properties looking to maximize available space.
Site Survey
A solar site survey is one of the first steps in determining if your home or business is suitable for solar energy. This detailed assessment evaluates your property’s potential for solar panel installation and helps design a system tailored to your needs.