Historically there are many examples of solar uses, strategies, and techniques In Arizona, but solar houses, as we think of them today, were not built until the 1940's. One of the earliest Arizona solar home designers was architect Arthur T. Brown who was instrumental in the design of an earth integrated passive solar home in Florence, Arizona in 1940, and other solar homes in the southern part of the state. One of his best known solar homes in Tucson incorporates a mass wall behind glass which stored solar heat in winter, keeping the house warm late into the evening. Brown provided for summer cooling with deep overhangs to keep the sun out; low vents on the north side and high vents near the south side ceiling for cross-ventilation; and the incorporation of evaporative cooling.

Definitions and Concepts

First and foremost, there is a great difference between an energy efficient building and a solar building. Solar buildings purposefully utilize the building's attributes of orientation, form, materials, and equipment to use the sun and other natural elements (earth, wind, water) to interact with solar and environmental conditions and resources to provide a unified, comprehensive approach to heating, cooling, lighting, water heating, cooking, etc.. A solar building, by definition, incorporates and builds upon energy efficient attributes, in its aggressive use and/or mitigation of environmental resources and conditions. An energy efficient building, while highly insulating and even efficient in its' energy consumption may not utilize the environmental resources that are available to provide for human comfort.

Solar building design approaches range from Passive Solar Buildings, (the building, form shape and materials are used to meet human comfort needs with little or no other power resources required) to Active Systems (mechanical devices powered by conventional and alternative energy sources are used to help collect, store, and distribute solar and renewable energy energy resource benefits and/or electricity to meet needs) to Hybrid Systems (a composite of the two).

Passive solar homes are those that use natural means -the sun - along with the heat transfer mechanisms of convection, conduction, radiation and evaporation to provide comfort. A passive building is designed to stay comfortable both winter and summer with little or no need for additional energy. Systems that depend on fans and pumps for their operation are called active. It a small amount of energy is used to run a fan and distribute heat (or coolness) throughout the house, the system is called hybrid. All require careful siting, spatial planning, and correct orientation to optimize effectiveness.

Solar design always considers the location of the building and the location of the sun. Since there are some basic rules of physics, and the sun's impacts change as it moves across the sky and is at differing angles to the earth's surface during the seasons, there are some fundamental rules of thumb for solar building design.