Architecture takes on climate control

The Jakarta Post , Jakarta | Fri, 10/13/2006 10:13 AM | Jakarta

Anissa S. Febrina, The Jakarta Post, Jakarta

What do Jakarta office towers and catwalk models have in common?

Here is a hint: They are nice to look at but expensive to maintain.

A recent study on thermal comfort and energy consumption could take us deeper into this seemingly superficial issue.

""For every seven buildings in the city, only one has both thermal comfort and low energy consumption,"" Tri Harso Karyono, a researcher with the Agency for the Assessment and Application of Technology (BPPT), said recently.

The best building in terms of energy-efficiency is the S. Widjojo Center on Jl. Sudirman, which features a slim triangular structure with shades on every opening.

Ironically, the Science and Technology Museum in East Jakarta's Taman Mini is the worst one with a sunroof that traps heat, increasing its interior temperature to up to 36 degrees Celsius. Its management must set aside Rp 80 million a month to cover its power bills.

Living in a tropical metropolis where average temperatures range between 23 and 37 degrees Celsius, office building managers must see to it that their tenants are comfortable enough to work.

Instead of making sure the structure itself enables a healthier microclimate, facility managements tend to rely on air-conditioning, which, unless it is supported by good architecture, leads to massive energy consumption.

Jimmy Priatman, who lectures at Surabaya's Petra Christian University, said the total cost of air-conditioning could reach up to 60 percent of the total electricity cost.

Priatman won the Asean Energy Award for his design for the Wonokoyo building in Surabaya, which annually consumes 88 kilowatts per hour (kWh) per square meter (sq m), a far lower rate than the Asean standard of 200 kWh/sq m/year.

Developed in the 1960s, the bioclimatic approach to design is responsible for the energy-efficiency of buildings like the Wonokoyo.

Energy-efficiency is achieved through passive means like the building's structural makeup and the selection of materials, architect Ken Yeang said.

Designing with climate in mind results in the reduction of overall energy consumption, leading to savings in the use of nonrenewable fossil fuels to generate electricity.

Lowering energy consumption further reduces the overall emission of carbon dioxide and waste-heat which reduces overall air pollution and the ""heat-island"" effect.

""The key is not to let sun radiation penetrate a building's facades. That can be done through shading or the use of appropriate materials like low-emission glass,"" Tri Harso said.

I-box

Jakarta's bioclimatically good and bad buildings
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Good Bad
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S. Widjojo Center Wisma BCA

Swiss Embassy Education Ministry building complex

Plaza BII ex-Religious Affairs Ministry building

Gran Melia BPPT building

Science and Technology Museum
---------------------------------------------------------------Source: BPPT research, Tri Harso Karyono, Asean Energy Award

Asean Energy Award criteria for energy-saving building
1. Consume no more than:

200 kWh/sq m/year for office buildings and libraries

240 kWh/sq m/year for malls

300 kWh/sq m/year for hotels

400 kWh/sq m/year for hospitals
2. Room temperature ranges from 23 to 26 degrees Celsius with a maximum humidity ratio of 70 percent
3. Have a maximum lighting ratio of:

15 Watt/sq m for office buildings

25 Watt/sq m for other facilities

Features and benefits of bioclimatic buildings
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Features Benefits
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Passive low-energy Contribute to sustainable future

Natural ventilation to Create a healthier built

lift-cores, staircases environment

skycourts Greater user satisfaction, provide

landscaping opportunities

Lift-cores as solar/wind Reduce energy consumption

buffer

Vertical landscaping Enable a more humane environment