When you’re researching solar or in the midst of the solar process, you’ll likely come across a lot of unfamiliar jargon. How to decode all this cryptic terminology? We’re here to help! We’ve created a glossary of solar words, alphabetized and divided into sections: acronyms, electricity, going green, how solar works, solar equipment, solar incentives, solar process, and types of solar. Read on to demystify solar power!
Acronyms
Perhaps the most perplexing of all solar words are the acronyms you’ll stumble across. With a term like ‘interconnection,’ you can make an educated guess. But what does PTO mean? Here are some common acronyms you may encounter during your solar experience.
EPC: Engineering, Procurement, and Construction. An EPC is a type of company, and seeking out a full EPC for your solar installation helps you know you’ve found not just a sales front, but a company prepared to handle every aspect of the process, from permitting now to maintenance in the future. Uprise is a full EPC.
ITC: Investment Tax Credit. This is another name for the 30% federal solar tax credit. Learn more about the ITC in our blog post.
PPA: Power Purchase Agreement. A PPA is a solar financing option; Uprise’s no-cost program is a PPA. But not all PPAs are created equal! Check out our blog post for what to watch for when you sign a PPA.
PTO: Permission to Operate. After Uprise installs your solar array and an inspector checks it over, we submit final paperwork to your utility company. Once they approve, they provide permission to operate. Then we officially turn on your solar system!
SREC: Solar Renewable Energy Certificate (or Solar Renewable Energy Credit). An SREC is a solar incentive available in DC, Maryland, and Virginia. When your solar array generates one megawatt-hour of electricity, you earn one SREC to sell. Learn more in our blog post on SRECs, or check out our article on how to choose an SREC broker, who will sell your SRECs on the market for you.
Electricity
Okay, so most of us aren’t electricians. What’s the difference between kilowatts and megawatts, or alternating current and direct current? Here are some answers to your electricity questions.
Alternating Current: electrical current that regularly reverses directions; this is the type of current most household devices utilize.
Direct Current: electrical current that flows in one direction; this is the type of current solar panels generate. Inverters convert it into the alternating current used in homes.
Feeder Lines: also called cross jurisdictional feeders or cross-border feeder lines, these are the part of the local electrical grid delivering power to your home. Around DC’s borders, there are Maryland homes on DC Pepco feeder lines, and these homeowners can access both Maryland and DC solar incentives! Learn more here.
Grid-Tied: solar systems that are connected to the power grid, enabling them to participate in net metering and draw power from the grid at night or in winter weather.
Kilowatt: a measure of power equivalent to 1,000 watts. Residential solar installations are typically measured in kilowatts.
Kilowatt-Hour: a common way to measure your home’s power use; for example, if you look at your Pepco bill, you’ll see your usage measured in kilowatt-hours (abbreviated kWh). Basically, if you use one kilowatt for one hour, that’s a kilowatt-hour.
Megawatt: a measure of power equivalent to 1,000 kilowatts or one million watts. Commercial solar installations are typically measured in megawatts.
Off-Grid: solar systems that are not connected to the grid. Uprise does not install off-grid systems; you’ll typically find them in remote locations with unreliable grid access.
Semiconductor: the material found inside a solar panel (typically silicon) that absorbs energy from sunlight.
Watt: a basic measurement of power. Solar panels’ output is typically described in terms of watts, such as a 400-watt solar panel.
Going Green
Solar is one component of sustainability, but you’ll come across other words like energy efficiency or electrification. What do these mean?
Energy Efficiency: using less electricity to achieve the same result, such as keeping your lights on or running your dishwasher. Energy efficiency can involve tackling phantom power use, weatherizing your home, or installing more efficient appliances, to name a few ideas.
Home Electrification: changing appliances and power sources so your home runs off clean energy instead of fossil fuel-generated energy. Home electrification involves going solar or switching to appliances like heat pumps or induction plates. Check out benefits and a case study from Uprise’s finance director here. As you may be picking up, home electrification and energy efficiency are very closely related.
Renewable Energy: electricity derived from naturally replenished resources, in the words of the Office of Energy Efficiency & Renewable Energy. Think sunshine (of course!) or wind, in contrast to finite resources like oil or natural gas. Tidal energy or geothermal energy are other examples of renewable energy.
How Solar Works
What’s a solar cell? A solar module? Dig into solar technology in this section of solar words.
Solar Cell: also known as a photovoltaic cell, a solar cell is a device converting sunlight into electrical current. There are either 60 or 75 solar cells in a solar panel.
Solar Efficiency: the percentage of sunlight that solar panels actually convert into electricity. Solar panels aren’t yet 100% efficient, due to factors like reflection, temperature, differing wavelengths, and panel angle. Most residential panels reach around 21% efficiency, although in the lab, scientists have been able to reach almost 50% efficiency. (Researchers are still working to lower costs for these more efficient panels; they are not cost-effective yet and currently exist only in a lab setting.)
Solar Module: commonly called a solar panel, a solar module is comprised of solar cells converting sunshine into power.
Peak Sun Hour: this isn’t every hour of the day when the sun is shining, but those hours in a day when the sun is shining brightly enough to produce 1,000 watts per square meter. The DMV receives around 4.0 to 4.9 peak sun hours per day, depending on the season.
Photovoltaic: converting light into electricity using semiconductors such as the silicon in solar cells.
Solar Equipment
You know solar panels are part of a solar array, but what other equipment is necessary? These solar words cover the nuts and bolts of your installation.
Bidirectional Meter: also called a two-way meter or net-capable meter, a bidirectional meter tracks how much excess power you send to the grid. Pepco can remotely update smart or digital meters to work bidirectionally, or they will replace your meter so it will work bidirectionally and you can participate in net metering.
Conduit: the protective pipe solar installers use to run wires from the roof down to your main service panel. Conduit is typically made of steel.
Energy Storage: also called battery storage or battery backup, energy storage is batteries able to store electricity from your rooftop solar panels for a rainy day, or for use at night. Batteries are not necessary for solar installations, but can be useful in certain situations like a power outage.
Microinverters: devices that transform the direct current electricity your panels generate into the alternating current electricity your home uses. Each solar panel connects to its own microinverter, allowing us and you to track each panel’s performance.
Racking: the framework for your solar panels that attaches to your roof or parapet walls. Learn more in our installation blog post.
String Inverter: devices that turn direct current into alternating current, like microinverters. However, string inverters connect all the solar panels together, so if one gets knocked out, they all stop working. In Uprise’s opinion, microinverters are the better option for modern solar installations. Learn more here.
Tier 1: a solar panel ranking system developed by Bloomberg New Energy Finance speaking to the reliability of the solar panel manufacturer. Tier 1 solar panels are made by companies with a reputation for quality that have been manufacturing panels for five or more years. These companies also typically offer better warranty support. Uprise installs Tier 1 solar panels.
Solar Incentives
Everyone’s favorite topic: solar incentives! Here’s how to make solar super cost effective.
Net Metering: if your solar array generates more power than your home uses, you send that excess power back to the grid and receive credits for it through net metering. Pepco, BGE, Dominion Energy, Potomac Edison, and Delmarva all offer net metering; learn more in our blog post.
No-Cost Solar: Uprise’s financing option allowing you to go solar at no cost. We believe everyone should be able to benefit from clean energy, regardless of whether you want to own solar panels or not. Learn more here!
Property Tax Exemption: DC, Maryland, and Virginia all offer property tax exemptions for solar installations, so that simply installing solar won’t raise your property taxes.
Solar Payback Period: also called the breakeven point, this is how long it will take you to pay back the cost of your solar installation, if you purchased your array with cash or a loan. This time period factors in the federal tax credit, SRECs, and utility bill savings. Since DC’s solar incentives are so good, the solar payback period here can be as little as three to five years. In other parts of the country, the solar payback period is typically closer to 10 years.
SRECs and the ITC: excellent solar incentives defined above in the acronym section!
Solar Process
On your solar journey, you may hear the solar words below from your project manager or construction team. And yes, you can make an educated guess about what interconnection means, but what’s its exact definition? Find out in this section.
Interconnection: connecting the solar panels to the local electricity grid. Uprise handles this application process with your local utility, who will then provide permission to operate.
Pitched Roof: a sloped roof, as opposed to the flat roofs common atop rowhouses.
Site Survey: after you approve your contract, our construction team will come out to your house to look at the space and condition of your roof, check out your main service panel or breaker box, and examine the area around your home to see where they may stage equipment or set up ladders. Your project manager will reach out to you to schedule the site survey.
Subcontractor: workers hired by a solar company to perform construction projects. These workers are not the solar company’s employees. Ask if your solar company uses subcontractors or their own employees for installations; there’s typically less accountability for subcontractors. Uprise’s own construction team completes all of our solar installations.
Types of Solar
What type of solar is on your roof? What about that large array on the ground you recently drove by? These solar words cover different types of solar installs.
Commercial Solar: a large solar array generating clean energy for a business. One example is IKEA’s solar car park in College Park, Maryland.
Community Solar or Shared Solar: a large solar array generating clean energy for renters, homes, or businesses. A few examples are the solar arrays at Fairfax Village in Southeast, or the solar canopy at Sargent Memorial Presbyterian Church in Northeast.
Ground Mount: solar panels attached to a racking system on the ground. Ground mounts are typically used for commercial or community solar arrays; most residential homes do not have enough space for ground mounts. One example is The Catholic University of America’s 7.5 megawatt West Campus Solar Array, which was completed in summer 2024 and is the largest urban ground mount community solar array in America.
Residential Solar: solar panels for homes. If you’re a homeowner in the DMV and you’ve gone solar, you have residential solar!
Go Solar!
While this glossary isn’t a comprehensive list of solar words, hopefully it answers some of your questions! And if you’re confused about a term we didn’t define here, give us a shout on social media and we can add it to the list.
If you’re ready to go solar, we can help! Call us at (202) 280-2285 or schedule a conversation with our team here. Bring your solar questions; we are all about simplifying and clarifying the process for you. And check out more explainer articles on our blog.