passivesolar.sustainablesources.comPassive Solar Design

Home Water Indoor Water Conservation Compost Toilets Pervious Paving Materials Xeriscape Greywater Irrigation Harvested Rainwater Water Budget Energy Heating and Cooling Solar Hot Water, Heating and Cooling Systems Energy Recovery Ventilator Programmable Thermostat Ground Source Heat Exchange Gas Water Heating Ductwork Radiant Barrier Ridge and Soffit Venting Fans Earth Sheltered Design Earth Sheltered Design Landscaping for Energy Savings Photovoltaic Systems Lighting Electromagnetic Fields Energy Efficient Appliances Materials Wood Dimensional Lumber Wood Treatment Non Toxic Termite Control Wood Flooring Engineered Structural Materials Engineered Sheet Materials Engineered Siding Wall Systems Structural Insulating Panels (SIPs) Straw Bale Construction Flyash Concrete Earth Materials Roofing Insulation Windows and Doors Cabinets Paints, Finishes, and Adhesives Floor Coverings Recycle/Reuse Home Recycling Compost System Construction Waste Recycling Shipping Container Housing About Portfolio Our Services Web Hosting Plans Backup Policy Web Development WordPress Monitoring, Update, & Backup Service WordPress Site Hardening WordPress Hack Recovery Web Hosting Plans Backup Policy Web Development Advertising Site Updates Staff, Contractors & Contributors Disclaimer Sitemap Payments Contact Us Green Bldg Pros Update Listing New Listing View Listings Search Listings Resources Books – Videos – Software – Periodicals International Straw Bale Building Registry Willing Workers in Appropriate Technology Green Building Databases & Design Resources StrawLocator Country Abbreviations Calendar Add Your Event Sustainable Sources: 24 years of online Green Building information DEFINITION CONSIDERATIONS COMMERCIAL STATUS IMPLEMENTATION ISSUES GUIDELINES Introduction Passive Solar Heating Passive Solar Cooling CSI NUMBERS Passive solar design includes many CSI categories. Some of these are: 03300 Concrete 03341 Insulating Concrete 03451 Architectural Wall Panels 04210 Brick 04212 Adobe Masonry 04220 Concrte Masonry Units 04400 Stone 08500 Metal Windows 08600 Wood Windows 08223 Glass DEFINITION Passive solar design refers to the use of the sun’s energy for the heating and cooling of living spaces. In this approach, the building itself or some element of it takes advantage of natural energy characteristics in materials and air created by exposure to the sun. Passive systems are simple, have few moving parts, and require minimal maintenance and require no mechanical systems. Operable windows, thermal mass, and thermal chimneys are common elements found in passive design. Operable windows are simply windows that can be opened. Thermal mass refers to materials such as masonry and water that can store heat energy for extended time. Thermal mass will prevent rapid temperature fluctuations. Thermal chimneys create or reinforce the effect hot air rising to induce air movement for cooling purposes. Wing walls are vertical exterior wall partitions placed perpendicular to adjoining windows to enhance ventilation through windows. CONSIDERATIONS: Passive design is practiced throughout the world and has been shown to produce buildings with low energy costs, reduced maintenance, and superior comfort. Most of the literature pertaining to passive solar technology addresses heating concerns. This information is useful and relevant in our area; however, cooling issues, which are equally important in Austin, are less well documented. Key aspects of passive design include appropriate solar orientation, the use of thermal mass, and appropriate ventilation and window placement. Consideration of high humidity is a key issue in Austin. For example, a basic passive cooling strategy is to permit cooler night air to ventilate a house and cool down the thermal mass (this can be brick, stone, or concrete walls or floors, or large water containers) inside the house. The thermal mass will absorb heat during the day; however, excessive humidity will reduce the cooling effect from the cooler thermal mass. Interior design elements of a home in our region also play a strong role in the effectiveness of passive cooling. For example, carpets, drapes, and fabric-covered furniture will absorb moisture from humid air, forcing the air conditioner to work harder to remove humidity. As a design approach, passive solar design can take many forms. It can be integrated to greater or lesser degrees in a building. Key considerations regarding passive design are determined by the characteristics of the building site. The most effective designs are based on specific understanding of a building site’s wind patterns, terrain, vegetation, solar exposure and other factors often requiring professional architectural services. However, a basic understanding of these issues can have a significant effect on the energy performance of a building. Commercial Status Implementation Issues T E C H N O L O G Y S U P P L I E R S C O S T F I N A N C I N G A C C E P T A N C E R E G U L A T O R Y Operable Windows Thermal Mass Wing Walls Thermal Chimney Satisfactory Satisfactory in most conditions Satisfactory in Limited Conditions Unsatisfactory or Difficult COMMERCIAL STATUS TECHNOLOGY: Well developed in passive heating but less developed in passive cooling. Wing walls are being researched as a ventilation strategy at the Florida Solar Energy Center, and effectiveness is being documented. A thermal chimney is a common design element in passive solar designs. Thermal chimneys are based on basic thermodynamics commonly used in passive design. SUPPLIERS: This is a design-based approach to energy and is practiced by some designers and architects in Austin. COST: The cost of passive design elements can run the same or slightly more than conventional building costs. This assumes that design services are used in both approaches – passive solar design and conventional design. Interior thermal mass materials such as stone and brick generally add to the cost of a home but can also be considered aesthetic enhancements. IMPLEMENTATION ISSUES FINANCING: There is not a financing issue unless the house does not include mechanical cooling. Lenders feel that the resale value of a home is reduced if mechanical cooling is not present. PUBLIC ACCEPTANCE: There is a basic understanding and acceptance in regards to passive heating among a large number of persons who have relocated here from colder regions. Passive cooling approaches are not well known. REGULATORY: According to the Energy Code, there are limitations on the amount of glass a building can have (25% if double-pane). It is normally not necessary to exceed that amount in order to achieve significant passive solar energy in Austin. However, this amount can be exceeded if an approved computer analysis shows that more glass will improve the energy use pattern in the building. GUIDELINES 1.0 Introduction Solar energy is a radiant heat source that causes natural processes upon which all life depends. Some of the natural processes can be managed through building design in a manner that helps heat and cool the building. The basic natural processes that are used in passive solar energy are the thermal energy flows associated with radiation, conduction, and natural convection. When sunlight strikes a building, the building materials can reflect, transmit, or absorb the solar radiation. Additionally, the heat produced by the sun causes air movement that can be predictable in designed spaces. These basic responses to solar heat lead to design elements, material choices and placements that can provide heating and cooling effects in a home. Passive solar energy means that mechanical means are not employed to utilize solar energy. 1.1 Passive solar systems rules of thumb: The building should be elongated on an east-west axis. The building’s south face should receive sunlight between the hours of 9:00 A.M. and 3:00 P.M. (sun time) during the heating season. Interior spaces requiring the most light and ...