Passive Solar Energy

Passive solar is the description of converting sun-light into for useful energy (normally heat & light) without the use of an active mechanical system. Examples are;

• ambient lighting
• building heating
• air-movement for ventilating

Passive cooling is the use of the same design principles to reduce summer cooling requirements. Passive Solar energy and architecture were well understood in ancient Greece. The Greeks knew that in winter the sun travels in a low arc across the sky, while in summer it passes high overhead. They built their houses so that the low winter sun could penetrate deep into the house via a south facing roofed porch called a portico. During the summer, the porch with overhanging roofs shaded the building to offer passive solar cooling. In better houses a courtyard protected the house openings from the cold northerly winds.

These design principals developed in ancient Greece serve modern Architects well today.

Retro-Fit Passive Solar Energy

In the U. K. and Ireland where we do not have to worry about excessive summer cooling loads. A sloping roof window offers a good way of introducing additional solar energy into a building. Extra light and heat can make a big difference in the building comfort levels and fuel requirements.

Active Solar Energy

Technologies that use a significant amount of conventional energy to power pumps or fans are active solar technologies. Most of this website deals with Active Solar Energy.

Hybrid Systems

Some passive systems use a small amount of conventional energy to control shutters, night insulation, and other devices that enhance solar energy collection and its storage. In these systems the definition between Active and Passive system blurs somewhat.

An external site with more information; http://www.alternative-energy-news.info/passive-solar-energy/