Photovoltaic Solar Panels

Grid-Intertied Solar-Electric Systems

Also known as on-grid, grid-tied, or utilityinteractive (UI), grid-intertied solar-electric systems generate solar electricity and route it to the electric utility grid, offsetting a business’ electrical consumption and, in some instances, even turning the electric meter backwards. A grid-connected solar-electric system is no different than living with grid power, except that some or all of the electricity you use comes from the sun. In many states, the utility credits an owner’s account for excess solar electricity produced. This amount can then be applied to other months when the system produces less or in months when electrical consumption is greater. This arrangement is called net metering or net billing. The specific terms of net metering laws and regulations vary from state to state and utility to utility. Consult your local electricity provider or state regulatory agency for their guidelines.

This building:

This facility contains a 50KW photovoltaic Solar Panel system mounted on the roof, with enough space for an additional 30KW of solar panels to be added in the future. This system provides on-site renewable energy to the building, which at times will even distribute power back to the electrical grid.  Electricity generated from the sun does not pollute our environment and reduces the demand for energy delivered through existing infrastructure. This building can expect to be supplied with 15% of its power from the solar panels.

Photovoltaic Solar Panels:

PV panels are a solar-electric system’s defining component, where sunlight is used to make direct current (DC) electricity. Behind a PV panel’s shimmering facade, wafers of semiconductor material work their magic, using light (photons) to generate electricity—what’s known as the photovoltaic effect. Other components in this system enable the electricity from your solar-electric panels to safely power your electric loads like lights, computers, and refrigerators.

PV panels are assigned a rating in watts based on the maximum power they can produce under ideal sun and temperature conditions. You can use the rated output to help determine how many panels you’ll need to meet your electrical needs. Multiple modules combined together are called an array.

Combiner Box/DC Disconnect:

The combiner box combines the multiple DC inputs coming from the solar panel terminations and routes them into one DC output. In the combiner box, the series strings of solar PV panels are joined together in parallel to increase the array current or amperage. Oftentimes the combiner boxes also employ a DC disconnect, which is used to safely interrupt the flow of electricity from the solar array. It is an essential component when system maintenance or troubleshooting is required. The disconnect enclosure houses an electrical switch rated for use in DC circuits. It also may integrate either circuit breakers or fuses, if needed.

Inverter:

Inverters transform the DC electricity produced by your PV modules into the alternating current (AC) electricity commonly used in most homes for powering lights, appliances, and other gadgets. Grid-tied inverters synchronize the electricity they produce with the grid’s utility grade AC electricity, allowing the system to feed solar-made electricity to the utility grid.

AC Breaker Panel:

The AC breaker panel is the point at which all of a building’s electrical wiring meets with the provider of the electricity, whether that’s the grid or a solar-electric system. This wall-mounted panel or box is usually installed in a utility room, basement, garage, or on the exterior of the building. It contains a number of labeled circuit breakers that route electricity to the various rooms throughout a facility. These breakers allow electricity to be disconnected for servicing, and also protect the building’s wiring against electrical fires.

KW-hour meter: