Passive Solar Design

Saving the environment and saving you money - on the cutting edge

There is no conflict between having what you want in an addition or remodel and passive solar design. In fact, passive solar enhances the design and your living experience by letting in light and becoming part of natural cycles.

Passive solar often costs no more than conventional construction. It's called "passive" because there are no moving parts, it is simply using the energy of the sun to heat the inside of your home in the winter, and keep it cool in the summer.

Anasazi cliff dwellings near Chaco Canyon, NM show how these descendants of an Archaic Desert culture used passive solar design to take some of the edge off of the bitter cold of the high desert winter, while remaining cool in the summer.

A properly-designed passive solar house or addition in Marin County, supplies for free about 67% of the annual space-heating needs. For a 1000 square foot space that adds up to approximately $261 in annual savings on your winter natural gas bill with a 90% efficient furnace at April, 2008 prices and $336 in savings if you have an older 70% efficient furnace. This savings is sure to increase as we burn through the legacy natural gas we were given. Natural gas prices have increased 175% in the past 9 years, 59% in the past 12 months and 30% in the past three months!

In addition, you'll be sparing the air the 18,976 pounds of CO2 annually that would have been created during the burning of the natural gas from your furnace.

This savings is for new construction that complies with California Energy Commission standards. If you are remodeling, the savings over an older home with single-pane windows, poor or non-existent insulation and an inefficient furnace will be even higher.

THE FOLLOWING GRAPHICS DEMONSTRATE HOW PASSIVE SOLAR WORKS:

Sunlight enters south-facing windows and strikes the thermal mass inside the home. The sunlight is converted to heat energy, which heats both the air and thermal mass materials. On most sunny days, solar heat maintains comfort during the mid-morning to late afternoon periods.

As the sun sets, it stops supplying heat to the home. However, a substantial amount of heat has been stored in the thermal mass. These mass releases the heat slowly into the passive solar rooms, keeping them comfortable on most winter evenings.

The home owner sets the thermostat back at night, so only minimal back-up heating is needed. Energy-efficient features in the home minimize heat losses to the outside.

The cool early morning hours are the toughest for passive solar heating systems to provide comfort. The thermal mass has usually given up most of its heat, and the sun has not risen enough to begin heating the home. During this period, the home owner may have to rely on supplemental heat. Energy-efficient features in the home minimize the need for supplemental heating.

For more information on Passive Solar, and what it can do for you, contact us!