Solar Energy Glossary

If you’re looking into installing solar for your home or business, you’ve probably come across new terminology specific to this industry. At Westcoast Solar Energy, we’re committed to providing our clients with well-designed, quality solar systems, an understanding of how solar power works, and answers to any solar energy questions they may have. We are available at (707) 664-6450, or contact us online!

Top 30 Solar Energy Terms and Definitions

  1. Annual Solar Savings: The annual solar savings of a solar building is the energy cost difference between a non-solar building and a solar building. 
  2. Alternating Current (A/C): A type of electrical current that reverses directions at regular intervals or cycles. In the United States, almost all power produced by electrical utilities shifts directions 60 times per second. 
  3. Array: Multiple solar cells make up a panel, and multiple panels form an array. This array is an interconnected system of photovoltaic panels that function as a single electricity-producing unit.
  4. Balance of System (BOS): The term balance of system stands for all other costs and components of a solar system. The components include physical parts other than the solar panels, such as inverters, wiring, mounting hardware, and monitoring systems. Costs include these parts, design, land, site preparation, system installation, and other related needs. 
  5. Batteries: Solar batteries store surplus energy that the solar power system produces to ensure you can enjoy solar power even after nightfall or when sunlight is unavailable. 
  6. Cells: This is the smallest semiconductor element, a single light-capturing unit within a PV module to convert light into electrical energy.
  7. Direct Current (DC): A type of electrical current where the electricity flows in one direction.
  8. Efficiency: Efficiency refers to the percent of sunlight the panels convert out of the total sunlight it receives. If you notice a drop in the efficiency of your solar panels, it is time to call for service
  9. Electrical Grid: An electrical, electric, or utility grid is a series of interconnected networks that deliver electricity to homes and businesses. 
  10. Energy Audit: The process where a homeowner or business owner assesses the amount of power they use and how they can make their building more energy efficient
  11. Federal Investment Tax Credit (ITC): The federal government provides a solar tax credit allowing homeowners and businesses to deduct a percentage of their solar PV cost from their federal taxes. 
  12. Grid-Connected System / Grid-Tied System: Grid-tied systems are connected to the local utility grid to draw power from in periods of low energy production such as night. Grid-tied solar systems are the most affordable and common type of system around.
  13. Ground Mounted Solar: An array of solar panels installed on the ground or land, usually done for large-scale solar projects. 
  14. Inverter: A device that converts direct current (DC) power generated by a solar energy system into alternating current (AC) power used by a home or building. The inverter plays a key role in the solar power system as it turns electrical energy into a usable form.
  15. Kilowatt Hour (kWh): A unit of energy equivalent to 1,000 watts acting over 1 hour. Kilowatt Hours are commonly used on utility bills to represent energy consumption. 
  16. Module: Also known as a solar panel, this device comprises multiple solar cells to form a circuit that absorbs sunlight to convert into electricity. 
  17. Mounting Hardware: The various equipment used to attach solar panels to rooftops securely. 
  18. Net Metering: Net metering is an agreement that gives solar PV system owners credits for the excess energy they sell to the utility grid. Home and business owners may use that credit to draw electricity from the grid as needed.
  19. Operations and Maintenance (O&M): Operations and maintenance are the continuing requirements of solar power systems, including repairs, cleanings, part replacements, and more. We offer our commercial clients O&M plans so they can rest easy knowing their system is working at peak efficiency. 
  20. Off-Grid: A type of PV system that runs independently from utility grids. They feature enough solar panels and battery storage capabilities to generate energy without access to utility-generated electricity. 
  21. Payback Period: The payback period represents how long it takes to “break-even” on a solar energy investment. It is when energy savings equal the cost of the system. In the United States, the average payback period is just over seven years. 
  22. Photovoltaic (PV) devices: These devices, such as solar panels turn light energy into usable electricity. Photovoltaic devices are usually made out of silicon, a naturally photovoltaic material. 
  23. Renewable Energy: Energy that is not dependent on finite resources. This energy is generated from sunlight, wind, geothermal heat, or tidal movements.
  24. Roof Mounted Solar: A PV mounting system where the solar panels are fixed on a home or business roof. This is the most common type of solar installation as they use up free roof space. 
  25. Solar Carports: A ground-mounted solar array lifted above parking lots to provide both shade and energy production. 
  26. Solar Design: The layout and orientation of a solar system optimized for maximum energy production based on the solar system type, angle of the sun, location, climate, and aesthetic appeal. 
  27. Solar Monitoring: A monitoring system used to see the solar energy system’s production power, usage, carbon offsets, and the impact the system has on electricity bills. 
  28. Solar Panel Cleaning: Buildup from dirt, dust, and other debris can reduce the efficiency of solar panels. While rain can wash away the bulk of the buildup, it may be necessary to clean solar panels with a hose manually or call an expert for professional servicing.
  29. Solar-Plus-Storage: This solar PV system includes a battery backup where excess electricity can be stored for later use, such as at night. 
  30. Tilt Angle: The angle at which a photovoltaic array is set to face to maximize the seasonal or annual energy collection. 

Still have questions about solar? Contact Westcoast Solar Energy, located in Sonoma County, California, to learn more.


  • This field is for validation purposes and should be left unchanged.

Creating Solar Energy Opportunities with these Great Organizations

Northern California Engineering Contractors Association
Solar Sonoma County
North American Board of Certified Energy Practitioners
California Solar Storage Association
Santa Rosa Chamber of Commerce
Rohnert Park Chamber of Commerce
Solar Power World
North Coast Builders Exchange