METTA Technological College – Cooling by Natural Ventilation

Allgemein

Stefanie Bauer, Karina Eder, Thomas Gruber, Katharina Höfler, Elvira Kinzner

Metta Technological College is a project that has been developed to offer Thai students a secondary education, focussing on technical and artisanal skills. The site is located in the heart of northern Thailand, in the province of Phetchabun.

Link: basehabitat.org

 

Thermal Simulations and Building  Physics  by Oskar Pankratz

 

©BASEhabitat
©BASEhabitat

LOW TECH SOLUTIONS
For Tropical Savanna Climate: hot, sunny, rainy, wet, little wind
• avoid sun – north/south orientation
• keep radiation out – insulation of roof
• as much shadow as possible – trees in courtyards
• use wind as much as possible – cross ventilation
• use day and night temperature difference – thermal mass
• slowly turning ceiling fans

©BASEhabitat

Preliminary Simulations: Compared Results,  Indoor -Temperatures at two  Classrooms with different thick insulation  of  Wood-Wool-Boards

X-Axis: Month; Y-Axis: Houres a Day; Colors: Temperature Range in Celsius; Temperature Comparison Classroom A (5 cm Wood-Wool-Board) and B (20 cm Wood-Wool-Board) The Temperatures in A are significant higher than in B. Keep in mind during holidays from March till the end of April are no students inside. In classroom B are just a few houres during a school year exceeding 32° C.. In hot countries the extendet comfort zone approximately goes up to 32° C, if the air speed is 2 m per second.
Boundaries

Daily crossventilation from midnight till 11 am. Classroom A Roof with 5 cm wood-wool-board, moveable openings 30 m² with insect-screen net opening 18 m².
Classroom B Roof with 20 cm wood-wool-board, openings 30 m² with insect-screen net opening 18 m².  Floor area, wall inclusive –   75 m²

Internal gains – 12 People from eight to six plus 8W per m² lights and fan.

Hottest day in April – comparison indoor-temperatures Class A and Class B
Remember – these are the temperatures during the holidays. During the hot hours, class B is 5 degrees lower than the outside temperature. 20 cm insulation is neccessary to achieve this 5 degree Kelvin difference between inside and outside. With 5 cm insulation you can expect 3 degrees Kelvin.
TMY2 artificial Weatherfile generated with Meteonorm

 

©BASEhabitat
©BASEhabitat
©BASEhabitat
Simulating the sun in Thailand – Whorkshop with Gregor Radinger and the students in Krems Donau-Uni Lichtlabor