In 1975 the Whitlam government handed independence to Papua New Guinea, no longer a colony of Australia. Hence this week’s 50th anniversary celebrations. Not long after, I was asked to develop better building regulations in PNG. That story is my small offering for the occasion.

As a registered architect working in Canberra on sustainability projects, I was approached by the redoubtable Ken Newcombe*, an environmental entrepreneur with a consultancy contract in PNG. One seemingly intractable problem was excessive energy used for air conditioning (AC) in buildings, from costly, highly unreliable generators dependent on oil and gas.

I was asked to investigate whether changing building designs, via in-building regulations, could alleviate the problems.

Early one morning in Port Moresby, in stultifying heat and humidity, I went to my first briefing with government officials in a four-storey building. We bypassed the lifts to climb three flights of stairs to the top-level conference room. I arrived exhausted and sweaty, not yet 9am. Was this some kind of hazing ritual for the new boy in town? I asked, to be told that no one gets in a lift in Moresby that doesn't have a UPS (uninterrupted power supply or independent electric generator). Brownouts, or blackouts, last hours. Best not be trapped inside a lift for a day.

The bureaucrats distilled a serious problem. Being near the equator, with high temperatures and vicious humidity, AC was wanted in every building where occupants are sedentary: offices, civic buildings, schools, universities, apartments, hotels, hospitals, courthouses, corporate HQs, and so on. But all electricity was derived, quite inefficiently, from oil-driven generators. It was costing too much for something that only worked intermittently.

But wait, it’s worse. Many older buildings, designed for natural ‘cross ventilation’, were being retrofitted with AC. These buildings, with ceiling fans or punkahs, were thermally comfortable for locals (similar to their houses) but were deemed uncomfortable by Western expats and a rising middle class.

Open, cross-ventilated buildings are terrible candidates for retrofitting AC in the tropics, causing the rampant energy increase. What makes them work so well naturally – the high rates of air flow from outside and within – makes them perform poorly mechanically when AC is added. All that high-energy, low-temperature air just leaks out, and the heat and humidity leak in.

A completely different building is needed for AC – using ‘outsulation’ (external insulation against radiant heat), minimal and well-sealed openings for windows and doors, wide shade, air locks, internal thermal mass, controlled air flow and so on. Design approaches we now understand as good sustainability for comfortable temperatures.

Designs need to be one way or the other. So-called hybrid buildings, currently popular in temperate climates, are technologically complex and would be ridiculously expensive in a third-world country in the tropics.

I needed to research the conundrum on the (very hot) ground and consulted some experienced expats; it was common for good Brisbane-trained architects, familiar with designing for tropical conditions, to work pre- and post-colonial rule.

Russell Hall had designed a village of houses for Air Niugini staff, some for pilots and seniors (individual) and some for staff (townhouses) on hills overlooking Port Moresby.

And he designed a retail and commercial building in Boroko: triangular, timber-propped, heavily shaded, and completely cross-ventilated.

Rex Addison, also trained at the University of Queensland, had worked magic on houses and a small library in Lae.

These delightful buildings used creative modernist forms to interpret the best vernacular Queenslander traditions. They were beautifully crafted and comfortable. It was clear that naturally ventilated buildings worked, particularly for those acclimatised.

But, as I had been briefed, many older buildings, designed for natural ventilation, were being retrofitted with AC. In buildings deliberately porous to air, the AC systems struggled against the heat infiltration. The AC both caused and was a victim of the frequent brownouts or blackouts.

Sometimes it was the inverse, where AC-based buildings were converted to natural X-vent. A striking example was the architecture school at the University of Technology in Lae, designed by Sydney’s Neville Quarry when he was the head of school. Unlike other buildings on the campus, which were designed for natural ventilation, this school intentionally had AC.

A strongly formed concrete and blockwork building, it was sealed tight to ensure the AC worked efficiently, but it frequently stopped due to power failures. The building was constantly thermally uncomfortable for students and staff, who reconfigured the way the building worked by taking out half the windows to create cross-ventilation, particularly in the two-storey voids.

There was a two-speed thermal economy: natural vs AC. How to accommodate that dichotomy in the building regulations? Could you have a hybrid building, designed to operate effectively one way or the other as needed? Could regulations avoid the twin evils: energy hungry yet thermally poor?

All building regulations derive from 1666, after the great fire of London. Health and safety. The twin peaks. PNG’s regulations in the 70s were based on Australia’s, which in turn were derived from the Brits. Totally inappropriate for the times and locations.

I set about codifying the issues: writing regulations that ensured a design had to be either naturally ventilated or fully air-conditioned. This decision would determine all the design features of the enclosing envelope. Hybrids were possible but unlikely given the increased complexity and costs. The controlling measure would be ‘energy demand per square metre’, or kW/sqm. I wrote a detailed report, duly forwarded to the PNG government.

Suffice to say it went nowhere. I comfort myself with the idea that I was ahead of my time. Energy and thermal comfort controls didn’t appear in Australian building codes (the notorious Section J) until almost 30 years later. Bolting energy and thermal comfort controls to health and safety is not easy. Only recently done in Australia, still not done in PNG.

The fight between the two building types goes on, here and there, temperate and tropical. It’s a hard conundrum to advocate for air conditioning in a country where deficits are driven by fossil fuels for power generation, but thermal comfort demands it. Fortunately, in the intervening 50 years PNG has developed some hydropower for electricity. A better, more reliable power source than the oil and gas of the 70s for the in-demand AC.

*Ken Newcombe had a storied career in the World Bank and founded C-Quest Capital in the USA, a pioneer in carbon offsets. Last year he was indicted over fraud in a ‘cooker replacement’ programme. He has been diagnosed with cancer, and the indictment has been postponed. My best wishes for his health, and heartfelt thanks to him for the clarifying opportunities so long ago.

Cross-Sections are Friday musings from Tone Wheeler, following on from Tone on Tuesday columns. Remember: amateurs draw plans, professionals draw sections; never at cross purposes.

Tone Wheeler

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