Solar panels convert sunlight into usable electricity.
Solar panels are most commonly installed on south-facing roofs, but they can be mounted on a variety of other structures and directly in the ground, using poles. The major components of solar systems are photovoltaic (PV) panels, wire and conduit, and inverters. Solar panels come with a 25-year warranty, but they often remain functional for over 40 years. Many solar systems installed in the early 1980s remain fully functional today. Grid-tied solar systems are incredibly resilient and have no moving parts, making them the most reliable source of renewable energy.
When sunlight hits the PV panels, direct current (DC) electricity is generated. This energy flows through wires to the inverter, which converts DC into alternating current (AC). From the inverter, the AC travels into an electric panel and is used to power your household energy needs. Most modern solar systems include built-in monitoring that allows solar owners to track real-time power production online.
Solar systems can be grid-tied or integrated with battery storage.
These days, most solar systems are grid-tied, meaning they are connected to an inverter that transfers power to and from the grid depending on whether a solar system is over- or under-producing relative to its household’s energy needs. If the electricity generated by a solar system exceeds household energy needs, surplus energy flows through an “export” electric meter, travels against the normal flow of electricity through the utility line, and feeds back into the grid where it supplements electricity supplied by utility companies. During periods of peak solar production, net metering allows solar owners receive credits on their energy bill equivalent to the amount of excess power produced by their system and donated to the grid. Grid-tied solar systems are dependent on the grid to operate. When power goes out, they shut down. This is to prevent solar power from feeding back into the grid and potentially injuring utility workers repairing power lines.
In the past, very few solar systems were grid-tied. Instead, most solar households relied on battery storage to ensure adequate energy supply during period of low solar production. Now, it is becoming increasingly affordable for solar customers to invest in a backup battery storage component for their grid-tied system. This addition offers a number of compelling features:
- Clean backup power during utility power outages. No need for fossil fuel-powered generators.
- Increased energy independence. Grid-tied solar owners with backup battery storage can choose to rely on their stored power at night or during low-production periods, reducing their dependence on the utility grid and on net energy metering.
- Utility savings. Using stored solar power during peak energy demand periods reduces the need to purchase supplementary power from the grid.
Net metering credits grid-tied solar households for their net excess electricity.
When a home or business installs a solar system, New Hampshire’s net-metering policy requires utility companies to upgrade their power meter. The new meter records the electricity exported to the grid by the solar system as well as the electricity imported during period of low production. Every month, utility companies issue energy bills that reflect the net amount of energy imported from the grid by solar households. Some utility companies, such New Hampshire Electric Co-op (NHEC), allow multiple solar PV systems to link up and a pay joint energy bill. In some cases, this is allowed even when the combined systems exceed the state’s net metering cap. However, the terms for such agreements are often less economical than for retail net metering.
Solar supplies dependable power all year, even during periods of low sunlight and heavy snow.
Both grid-tied and battery-integrated solar systems provide a reliable source of clean power that is dependable all year long. Because both systems account for excess power generated during peak production times, solar power can be made available even in periods of low sunlight or when panels are covered with snow. Snow cover raises concerns for many solar customers, but because snow occurs almost exclusively during periods of minimal sunlight, solar production is already at its lowest and any additional losses are statistically insignificant.
Grid-tied solar systems are the single most reliable source of renewable energy. They promise a long term source of clean, dependable, and affordable energy. Many systems generate enough power to account for 100% of their household’s energy needs. Click here for more information on how solar would benefit your home, business, and state.