Clima e Temperatura

Passive Solar BuildingSmart, simple solar

Keya Lea Horiuchi

GreenPassiveSolar.comfacebook.com/greenpassivesolar

twitter.com/GreenSolarMag

1Saturday, September 15, 2012

Passive Solar Elements

• Orientation / Southern Facing

• Overhang, Solar Control

• Solar Heat Collection - Windows (glazing)

• Materials: Thermal Mass

• Insulation


Advantages

• Can enable to be off the grid

• No bills

• Harness the power of the sun

• Many, many more


Passive vs. Active Solar

• A passive solar building will simply, passively sit where it is located and be efficient because of its design. The design is based off of the movements and available energy of the sun, as well as the materials used to construct it.

• Active solar heating and electrical systems also use the sun’s energy but with additional mechanical means used in the process of harnessing its energy. Photovoltaic (PV) panels, pumps, thermostats and fans are objects that are commonly referred to as being active solar because they need some electrical input or conversion for their systems to function.

• Passive and active solar elements are commonly combined.


How Passive Solar Works

A passive solar building is designed and built based on utilizing the constants within the surrounding environment, centered around the movement of the sun.

When a passive solar building is designed and build well, the building simply, passively sits there and will be warm in the winter when it is cold outside, and will be cool in the summer when it is hot outside. (It’s like the Aikido of martial arts.)


A building must face the south in order to capture the sun’s energy.

Building Orientation

The long side of the house should be on an east - west axis.


Used Throughout History

The Anasazi of the Southwest built in the southern facing cliffs. This created shade in the summer and full sun in the winter. The stone (thermal mass) absorbs and radiates heat in the winter. It keeps the living area cool in the summer.


The Sun’s Movement


The Sun Throughout the Seasons

A pinhole photography artist strapped a camera to a telephone pole and recorded the sun for one year.

The sun’s path on the summer solstice is thehighest and widest arc, while the lowest and most narrow arc shows the sun’s path on the winter solstice.


Cliff house dwellingsat Mesa Verde.

Summer (top)Fall (right)


Overhang / Solar Control

Overhang / Blocking Summer Sun


Overhang / Block the Sun


Solar GlazingAKA

WindowsOn the southern side of the house

(In the northern hemisphere)

Windows allow solar heat into the house in the winter so that (ideally) the heat is absorbed into the thermal mass.


Thermal Mass

A material that has thermal mass is one that has the capacity to absorb, store and release the sun’s heat energy. Its density and levels of conductivity help to keep the internal temperature of a building stable. Objects that have thermal mass have inherent qualities for both heating and cooling.

Water also is very dense and has a high capacity to store and release heat.


Greenhouse“Heat Sink”

- 2 feet of crushed gravel

- Fans pull hot air to a manifold located under the rock

Passive Solar Homes Must Have Thermal Mass

- Masonry Stove- Kitchen Tile


Trombe WallOther ways of bulking up with thermal mass.


The Trombe wall absorbs and radiates solar heat in the winter, while its mass keeps the house cool in the summer.


The Trombe wall is painted black to absorb the maximum amount of solar heat. 2 feet gap.


Modifications to the Trombe Wall

Solar Decathlon 2011 - Solar Homestead from Appalachian State

The material that absorbs the sun’s solar heat is rectangular shaped, with a metallic casing that has been painted black and filled with a plant-based oil mixture. The mixture is a phase change material (PCM) that becomes liquefied when it warms and slowly releases the heat through the cooler evening and night as it returns to a waxy solid material.


Insulation

Stay cool in the summer and warm in the winter.


This roof is referred to as an ‘Idaho’ double roof. It is a roof with two separate roof systems comprising 20 inches.Beyond the tongue-and-groove wood paneling is a high density fiberglass insulation, followed by a layer of aluminum foil. Beyond that is a 4 inch urethane SIP (structured insulated panel) that is then covered by a metallic roof.

Passive Solar Works Best With All Elements Working Together.

The Importance of Insulation


Insulation vs. WindowsWhen a house is closed to the elements, most of the heat is lost through the windows. Passive solar houses absorb solar heat through the windows on the south side, while they minimize heat loss through the windows on the north side of the house.


Passive Solar Houses - Should be well-insulated- Windows (glazing) facing the south, minimized on the north.


Retrofitting to Passive Solar


From Farm House to Passive Solar


Inside the Retrofit


EarthshipsThe Earthship type of housing, imagined into actuality by architect Michael Reynolds, uses recyclable, easily available materials to create a type of housing that can potentially sustain a household living off the grid.

A passive solar type of building, the Earthship collects its own water, has its own water treatment system, can grow its own vegetables and generate its own electricity from solar photovoltaic (PV)panels and wind turbines.


The ancient Greek playwright Aeschylus:

“Only primitives & barbarians lack knowledge of houses turned to face the Winter sun.”


GreenPassiveSolar.com

Keya Lea Horiuchi

facebook.com/greenpassivesolar

twitter.com/GreenSolarMag


Clima e Temperatura

Documents

Transcript of Clima e Temperatura