Types of Solar Power for Your Home

When deciding whether or not to “go solar”, it is important to consider all the types of solar power installations and technologies. Specifically, there are three things to consider when making the decision to invest in solar power:

1. What type of solar power system? Solar electric or solar hot water?
2. Where to locate the solar power system and what type: building integrated or roof-mounted?
3. Is the building connected to the electric grid or is it “off-grid”? 

Types of Solar Power

There are basically two types of solar power technologies for homes and businesses. The most popular technologies are solar photovoltaic systems (PV) that turn sunlight into electricity. The second technology is solar hot water or solar thermal systems that use sunlight to heat water. This heated water can be used to offset natural gas demands for a hot water heater or can be used for pool heating or space heating or cooling. For more information on solar hot water technologies, go to Solar Hot Water (link to solar hot water page). The Million Solar Roofs Initiative was established to offset electricity demand and therefore is set up to primarily drive a market for solar PV systems. 

Locations and Types of Solar System

Solar electric power systems can be installed anywhere that receives sunlight. The best location is a spot that receives plenty of sunshine, which in California is when a system faces south or southwest. That said, there are different ways to locate a solar panel on a property:

1) Roof-mounted systems: these systems are the most common in California. They typically are 20’x20’ in dimension, located a top a south-facing roof or on a flat roof and are mounted via bolts. The system can be mounted on a home or business roof or on a trellis or garage that is either connected or detached from the main building.

2) Ground mounted systems: These systems are located in open space areas, usually a backyard with plenty of space. They are typically the same technology as is found on roof-mounted systems but are sometimes installed as “tracking” systems where the solar panel rotates to follow the sun across the sky throughout the course of the day.

3) Building integrated: By far the most exciting development in solar power technology, building integrated systems literally take on the form and shape of the building on which they are installed. The most common of these types of systems are solar shingles that seamlessly blend into a roof, replace roofing material. Other promising developments along these lines include solar windows.
 

Off-Grid and Grid-Tied Solar

Some Californians are choosing to install solar on an “off-grid” solar home or business. In this situation, the building does not receive electricity from a utility or from the electric grid but rather is entirely self-sufficient for its electricity. While a more expensive way to go solar (costly batteries are usually required), one of the main benefits of an off-grid system is that the home or business is protected against blackouts.

The vast majority of Californians are installing “grid-tied” solar systems, however. In fact, connection to the grid is a basic eligibility requirement of California’s rebate program. The upside of installing a grid-tied system is that it is generally cheaper, as it negates the need for a battery. The downside is that the building is not actually protected from blackouts. This is because the solar panel is on the utility side of the meter so if the grid goes down, so does the solar system.