An Overview of Integrated Passive Heating and Cooling Design

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1 An Overview of Integrated Passive Heating and Cooling Design

2 Definition Passive Heating Building Site and Orientation Thermal Mass - Glazing Thermal Mass - Mass wall Thermal Mass - Sunspace Insulation Insulation - Envelope Back-up Heating Passive Cooling Sources of Excess heat Passive Cooling - Ventilation Passive Cooling - Blinds/Shading Passive Cooling - Landscaping Resources Contents

3 Passive Solar Heating and Cooling Defined: -the incorporation of certain design features into a building to utilize solar energy and thermodynamic principles to heat and cool an interior space, without mechanical systems. These features include an aperture or opening, a control element, absorber, thermal mass, and ventilation or distribution of the heat. Design

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5 Passive Heating Energy use within the Home Types of energy used

6 Building site and Orientation Principles 1. Utilize Green Building materials 2. Urban opposed to rural a. retain open spaces 3. Long axis of house corresponding to East and West (within 10 degrees of true South) 4. Unobstructed Solar exposure

7 Thermal Mass - Glazing Direct Solar gain solar radiation received directly into a space through an aperture 1.Openable and non-openable windows 2.Multi-pane with low emissivity (low-e) 3. Framing material a. Wood b. Wood/Vinyl composite c. Fiberglass 4. Include storm window addition 5.Placement and percentage of total floor space of house (glass minus frame) North and East-facing: less than 4 percent West-facing: South-facing: less than 2 percent 7-20 percent, optimum 12 percent Ex sq. ft. home at 12 percent = 162 sq. ft. of glazing

8 Thermal Mass Mass Wall Indirect Solar gain solar radiation received indirectly into a space usually through thermal mass 1. Glass/Mass ratio a. each sq. ft. over 7 percent glazing 1. lit floor, 1:5.5 sq. ft. 2. unlit floor, 1:40 sq. ft. 3. mass wall, 1:8.3 sq. ft. 2. Positioning of Mass Wall a. Exterior wall type not efficient b. Interior: Dense Type, just behind glass, such as a Trombe Wall 1. concrete/block 2. brick 3. adobe 4. tile 3. Thickness a. at least 4 in. thick, no more than 6 in. thick 1. Coloring should be dark

9 Thermal Mass - Sunspace Isolated Solar gain Solar radiation received directly into a space, allowing captured heat to radiate through other spaces 1. Type a. Enveloped sunspaces one outside wall 1. all glass roof and wall b. Attached sunspaces three outside walls 1. attachment to other spaces a. no wall b. glass wall c. standard wall d. mass wall

10 U.S. Dept. of Energy Climate Zones with heating type and insulation values Insulation

11 Insulation - Envelope Principles 1. Insulate foundations, floors, walls, and attics/ceilings 2.Exceed region-specific codes and R-values a. Zones 5/6 (Lower Peninsula) 1. Floors: greater than R Walls: greater than R Attic: greater than R Install formaldehyde-free insulation 4. Install radiant barriers 5. Install moisture or vapor barriers a. behind drywall in colder climates b. behind exterior paneling in warmer climates

12 Back-up heating Principles 1. properly sized units based on demand (Btu) 2. types available a. Oil b. Electric c. Heat Pump e. Propane d. Nat. Gas f. Wood/pellets 3. efficiency of unit

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14 Passive Cooling

15 Sources of excess heat Internal 1. Sources a. lighting 1. incandescent b. appliances c. human 1. stoves/ovens External 1. Sources a. heat transferred from roofs, walls, and windows through thermal conduction and radiation b. insufficient overhangs c. lack of proper shading 1.blinds/shades 2.landscaping

16 Passive Cooling - Ventilation 1. Indoor Air Quality 2. Types a. natural 1. open windows b. chimney effect 1. use of second-story windows c. earth cooling tubes d. venting of Trombe walls and sunspaces

17 Passive Cooling - Blinds/Shading 1. Interior a. Types 1. Curtains 2. Blinds 3. Internal rigid shutters North Latitude F-Factor 2. Exterior a. Types 1. Arbors 2. Awnings 3. Trellises 4. Louvers 5. Roof overhang, length or F-Factor Length (L) = Height of opening (H)/F-Factor (Lansing is 42 0 North Latitude)

18 Passive Cooling - Landscaping 1. Types a. native b. deciduous vs. evergreen 2. Placement a. greater than 17 ft away from South-face b. at angle greater than 60 degrees from South-face

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20 Resources Printed Source: 1. Chiras, Daniel D. The Solar House: passive solar heating and cooling. White River Junction, VT: Chelsea Green Publishing Company, Print. 2. Findley, David S. Solar Power for Your Home. New York: The McGraw-Hill Companies, Inc., Print. 3. Hinrichs, Roger A., and Merlin Kleinbach. Energy: Its Use and the Environment. Fourth ed. N.p.: Thomson Brooks/Cole, Print. Internet-based Source as they appear: www1.eere.energy.gov 8.