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Solar

The warmth and light of the sun can be captured and used to increase the energy efficiency and comfort of a home. Incoming solar energy from the sun is a clean, renewable source available at no cost. Solar energy can be harnessed in two basic ways, active and passive, to benefit the homeowner.

Passive Solar

Passive solar refers to using the sun's warmth and light to help heat and illuminate a home. Passive solar homes are designed to take advantage of the sun's energy, lessening reliance on electricity or other types of energy for space or water heating. The design of a passive solar home uses the windows, walls, and floors to collect, store, and distribute the sun's energy. Passive solar design does not rely on mechanical or electrical equipment to function.

 

Some passive solar homes are heated almost entirely by the sun. Other homes incorporate some elements of passive solar design, such as south-facing windows, to reduce the energy needed for heating. Although some climate areas are better suited to passive solar homes than others, elements of passive solar design can benefit homes regardless of location.

The homeowner can capture maximum benefits from a passive solar approach when designing a new home. However, renovating or retrofitting an existing home can provide an opportunity to incorporate selected principles of passive solar design.

Active Solar – Photovoltaics

Another way of using solar energy is to convert sunlight directly into electricity by using a photovoltaic (PV) system. This active solar approach allows a home to generate some or all of its electricity on site. With a PV system connected to the utility grid, it is possible for the homeowner to sell excess electricity back to the utility.

Home PV systems are becoming steadily more affordable, efficient, and durable.

 

How Photovoltaic Systems Work

A home-based PV system relies on solar cells made of semiconductor materials to convert sunlight directly into electricity. When sunlight shines on the semiconductor material, the solar energy knocks electrons loose from their atoms. These free electrons then travel into a circuit built into the solar cell and create electricity. Each individual solar cell produces only a small amount of electricity but connecting them in larger panels or modules increases their electric capacity.

Normally, solar panels are installed on the roof. While PV solar systems can generate electricity without intense, direct sunlight, the sunnier the location, the better the system will operate. Home PV systems can be found throughout the United States. The southwestern region of the country is where PV systems are most common due to the large amounts of solar energy and sunlight found there.