How Does Solar Energy Work?

Solar Energy Defined

Solar energy is technically referred to as solar photovoltaics. Photovoltaic can be translated in to Light(Photo) Energy(Voltaic). Certain semiconductors produce electricity when exposed to light. The electricity created is solar energy.

Different Electricity Types

A general understanding of two major electricity types is helpful when learning how solar works. We regularly use two types of electricity in the United States: D.C. electricity and A.C. electricity.

• Direct Current (D.C.) electricity is more commonly used in low voltage applications, like small electronics. For example, batteries provide DC electricity to small portable electronics and larger applications like vehicle batteries.
• Alternating Current (A.C.) electricity is the common electricity delivered to our homes and businesses from the electric utility companies. AC electricity is more common than DC electricity because of its early ability to safely transmit electricity long distances.

Solar Panels produce DC electricity and can be fed directly to DC loads or inverted in to AC electricity using power conditioning equipment called solar inverters.

How Different Solar Energy Systems Work

We utilize solar energy in the three system types we offer: grid-tied, grid-interactive, and off-grid

• Grid Tied Solar:

Grid-tied solar is the most common installation type. DC electricity from the solar panels is fed to an inverter where the electricity is inverted in to AC electricity. The solar energy is then directed to the electrical distribution panel where it feeds the home or businesses loads. The inverters feed the solar energy at a slightly higher voltage than the electric utility. This allows all loads first utilize the solar production. Any excess electricity is fed in to the electric utility where it will power nearby homes and businesses.

Net Metering: The power fed in to the utility is a positive credit that will be subtracted from negative consumption in your electric bill. (Large commercial systems may not be able to net meter in certain utility areas)

Tariff and Value of Solar: Tariffs monitor your solar production before you consume it. In this scenario, the consumer will be the owner of a solar power plant and sell their solar energy to the grid. They will be charged for all energy they consume with a separate meter. The Austin Energy Value of Solar method works similar to this but the solar energy production will be subtracted from the bill and over production will never be given a check.

Grid-tied solar does not provide solar energy during electricity outages. This a safety feature that is required for grid-tied solar arrays without energy storage. This prevents power from feeding in to the grid while lineman are making utility repairs.

• Solar with Backup Power:

Solar with backup power is a grid tied system that also has energy storage for electricity outages. Grid-interactive systems completely isolate your home or business from the utility in an utility outage. Energy storage provides constant electricity to your loads utilizing both stored energy and solar production.

• Off Grid Solar:

Off grid solar utilizes solar panels with energy storage to provide power systems for remote areas or customers looking for alternatives to electric utility power. Our systems often integrate generators to lower the battery bank size and cost. We can also integrate wind and hydro power in our systems. However, cost and maintenance disadvantages compared to solar PV have limited the benefits of these technologies (wind and hydro) in residential and commercial applications. Our systems are custom designed for the end user’s needs. We can power DC loads as well as 120/240V and 120/280V AC Systems.