Solar energy Passive solar utilizes building design an placement to maximize heat in the winter and minimize heat in the summer. It is only building, not use of technology or generating electricity or heating water. Active solar uses technology to focus, move or store solar energy. Typical active solar will generate electricity or heat water.

Three types of Active Solar 1.Flat plate technology – used to heat water 2.Photovoltaic (PV) – Used to generate electricity for homes or businesses 3.Concentrating Solar Power (or CSP) and is used for large scale electricity generation – for a large corporation or utility company.

1) Flat plate solar collectors (solar panels) = one active method for harnessing solar energy – Dark-colored, heat-absorbing metal plates Water, air, or antifreeze pass through the collectors, transferring heat throughout the building Heated water is stored and used later – primarily for solar water heaters for home hot water use!

2. Photovoltaic cells generate electricity A. Photovoltaic cells = collect sunlight and convert it into electrical energy B. Photovoltaic (photoelectric) effect = occurs when light strikes one of a pair of metal plates in a PV cell, causing the release of electrons, creating an electric current C. A PV cell has two silicon plates, the n-type layer (rich in electrons) and the p-type layer (electron poor) – Sunlight causes electrons to flow from the n-type to the p-type layer, generating electricity

3. Concentrating Solar Power - CSP A. CSP has several advantages over PV Cells for electricity generation – the heat that is generated by this system can be stored in an insulated container to generate electricity after the sun goes down. B. The heat concentrated by the mirrors boil fluid to produce steam and run turbines. These boilers can also use natural gas, which would allow continuous energy production on cloudy days. Produces A LOT of electricity, for a utility company