Energy Efficiency & Alt Energy Sources Flashcards
Cool Climate design strategies
- use compact forms with the smaller surface area possible relative to the volume
- use large, south facing windows with small windows on east and west with minimal or no windows on north
- use interior materials with a high thermal mass
- include summer shading for glazed areas - use dark or medium-dark colors for the building exterior
Hot-Humid Climate
design strategies
- provide shade for all openings
- maximize natural ventilation with large openings, high ceilings and cross ventilation
- construct bldgs using light materials, minimize thermal mass
- use light colors for building exterior
Hot-Arid Climate design strategies
- use compact forms with the smallest surface area possible relative to the volume
- minimize opening sizes
- provide shade for openings
- maximize thermal mass
- use light colors for the buildings exterior
Optimum Building Orientation
Solar Radiation
- The South wall of a building receives max. solar radiation in the winter
- The roof and east and west walls of a building receive max. solar raditation in the summer
South Wall Sun Control
Temperate Climate design strategies
- plan rectangular bldg w/ long direction oriented along the east-west axis and facing slightly to the east
- provide shade in the summer -allow the sun to fall on glazing and the building in the winter
- use south facing opening to capture winter sunlight
- plan for the cooling effects of wind in the summer, block the wind in the winter
- use medium colors for the buildings exterior
Green Roof Construction
Sun Angles
Trees as sheild fro winds
- a row of trees of a certainheight will decrease the velocity of the wind between 30% and 40% at a distance about five times the height of the trees
- Trees planted next to a building may reduce wind velocity between 20% and 60%, depending on the density of the trees.
- The effect of trees on reducing wind velocity decreases greatly at about 10 times the tree height and is negligible beyond 20 times the tree height
Horizontal Shading Devices
- Shade on South side of building
- Moderate overhangs
- Horizontal louvers
Vertical Shading Devices
- Shade on East and West side of building
- Very wide overhang
- Veritcal louvers
Earth Shelter Types
- Built above gorund and has earth bearm against the walls on one or more side
- Built into the side of a hill, ideally with the north side built inot himm and south side exposed for solar heating, views and daylight.
- Completey burried below grade with a courtyrad in the center for access, daylight, outdoor living and ventilation.
Green Roof Advantages
- conserving energy by reducing cooling and heating loads
- reducing storm runoff
- absorbing carbon dioxide
- reducing ambient air temperatures
- filtering the air and binds dust particles
- reducing the heat island effect normally caused by roofing
- protecting the roofing from ultraviolet light degradation, temperature extremes, wind, and hail
- adding acoustical insulation
- adding aesthetic appeal to the roof
Air Locks
- A vestibule entry system is desirable in cold and temperate climates and can be beneficial in hot climates where a building is mecbanically cooled.
- Air locks minimize heat loss when people enter and leave a building.
Direct gain systems
collect heat through south-facing glassand store the heat in high-mass materials such as:
- concrete floors
- masonry walls
- tile
- stone
- terrazzo
Thermal Storage Wall
(Trombe Wall)
placed directly behind a South-facing glass wall and collects solar energy during the day for release at night, similar to a direct gain system. Most thermal storage walls are vented, which allows cool air to circulate in the space between the glass and wall, become heated, and travel by convection up and over the wall and back into the space.
Greenhouse
