For the human body in light tropical clothing, the most comfortable temperature would be 22 degrees, with humidity around 50 - 60%. This is usually what we mean by "airconditioning" in Singapore.

This tells us a simple fact: through the 365 days in a year, no daytime is ever comfortable. Only a few nights in December and January, with their 23 or 24-degree minimums, approach the ideal of 22 degrees

In the worst week of last month, I was reminded of the discomfort of our climate each time I had to leave my office or my home. On scorcher days, just crossing the road left me sticky with sweat. It's not good enough, I kept telling myself, that we only aircondition the insides of buildings (and not all of them, for that matter), we still need to get from building to building!

Around the same time, Lee Kuan Yew spoke about making Singapore a fun place, and as I mentioned in the article The erotic is too much fun, the obsequious media here immediately got to work making this the topic of the week. Among the people they interviewed, asking for opinions whether and how Singapore could be a fun place, was one who said -- I thought he struck the nail on the head -- we must do something about the climate!

Indeed, if Singapore wants to be a city with buzz, we must address this issue. Buzz is liveliness in the social sphere. People interact, they have a good time, they network, they get together to canvass for petitions, donations, and all manner of consciousness-raising. For a city to be alive, our common social space, physical, as much as intellectual, must be full of activity.

Of course, the utopian dream would be to build a huge dome over Singapore airconditioning the entire city-state. Well, none of us will see this in our lifetime, but that doesn't mean we can't do much more than we are doing now. What we lack -- and this is the point of this essay -- is imagination. In two ways: imagination in our intellectual, political and civil space that sows the seeds of buzz; and imagination in creating a physical city that is conducive to buzz, which is the aim of this piece.

The ever popular atrium in Raffles City

There are some knowns which we can use as starting points to imagine a future.

The first known is that there is a remarkably successful building form in Singapore: the airconditioned atrium. They have become the leading social spaces in our urban geography. From the White Sands Mall in Pasir Ris in the eastern end of Singapore to Jurong Point in the west, Singaporeans throng the malls with atriums. They're places to shop, eat and generally escape the heat of the day.

It's easy to build malls with large atriums on greenfield sites, but even in the inner city where historic facades of shophouses may have to be preserved, one developer has shown the way. In Bugis Junction, the developer kept the facades and parts of the old buildings, glassed in the pedestrianised streets between them and airconditioned the whole. Singaporeans just love it. They throng the shops, they dine "al fresco", which at Bugis Junction means sitting at tables set out in the airconditioned street.

At Bugis Junction, an old street was glassed over and airconditioned		Airconditioned 'al fresco' at Bugis Junction

Atriums are where what buzz Singapore has, is.

But our atriums don't go far enough. Besides being disconnected from each other, with buildings often separated by 6 lanes of heavy traffic in the furnace that is our climate, they are all privately owned commercial areas, with specific opening and closing times. The result is discontinuity in space and time, and thus a failure to achieve critical mass. While they are very successful in themselves as commercial centres, they don't add up to a city that never sleeps.

But won't ever larger atriums mean a heavier energy bill?

That's were we come to the second known: Singapore is an energy-rich country. We may not have oil, coal or natural gas, but we have so much solar energy, we curse it. Our problem is that we have no clue how to harness it, yet with the oil price now above US$50 per barrel, with some analysts predicting US$100 per barrel within a few years, we had better try.

I can almost hear the rejoinder: the technology -- and I'm referring primarily to solar cells -- is still in its infancy. This is the oft-heard kind of rejoinder that defeats us. It shouldn't matter what the state of the technology is in America or wherever, we should be the ones driving the research. We have to be able to imagine Singapore as the centre of excellence for solar energy research in tropical conditions. After all, we are the richest city within 20 degrees latitude of the Equator. If we're not doing it, who will?

The third known is that solar cells can be remarkably versatile. We imagine them as large black panels mounted on roofs or the wings of the space station, but they can take many more forms than that.

Cafe in Raffles City. Note the louvres in the window glass. They could just as easily have been solar cells in strips.

To begin with, they can be very thin, less than a millimetre. They can be mounted on various substrates, e.g. steelfoil or glass. They don't even have to be opaque. The solar cells can be arranged in strips on glass, such that from inside the building, it looks like a window with louvres. This sounds just perfect, for most of us wouldn't want the full blast of sunlight into our rooms. Filtering away 60 – 70% of the light would be ideal, leaving our living and working spaces bright enough without heat and glare.

At present, where does the remainder of the sun's energy go? It either gets reflected away by the mirror-like glass surfaces, or more often than not, converted into heat through absorption into the black tint of the glass, the concrete walls, and other surfaces that the sun strikes. Wouldn't it be better if those surfaces were faced with solar cells making good use of the energy received, e.g. helping to drive the airconditioning system?

It should be noted however, that currently, the efficiency of solar cells is rather low. Crystalline silicon cells convert only about 15% of the sunlight received into electrical energy. Amorphous silicon cells seldom do better than 6%, though they are cheaper and simpler to manufacture. In lab conditions, however, efficiency rates of 30% for crystalline solar cells have been reported, but how far this is from commercial application remains to be seen.

An Australian company has taken a non-silicon approach. Taking inspiration from plant photosynthesis, it has come up with a dye-based solution, said to be much cheaper. It can also be made into various curved shapes, and take the form of semi-transparent and translucent screens. However it's not yet on the market.

What this does show is firstly, that the technology is on the move, and secondly, Singapore is, as always, is distant follower rather than a trailblazer, even if we have more reason than any other city in the world to be on the leading edge of the technology. What a disgrace!

The main drawback holding back widespread use of solar cells is cost. Although, with no moving parts, these panels have very long lifespans (said to be 30 years on average), the initial cost for an assembly of solar panels large enough to make a real difference to the energy ecology of a building is a hefty one. In the days when crude oil was typically US$20 a barrel, it simply wasn't economical.

Since it is unlikely that we'll see US$20 a barrel for a long time to come, given the increasing thirst of China (and soon, India) for imported oil and gas, the time to get serious about solar energy is now.

Furthermore, the manufacturing technology behind silicon solar cells is a form of semiconductor technology. We boast a semiconductor industry in Singapore (though detractors tell me we're far, far from cutting-edge in the R&D department), so it shouldn't be a great leap into an area where we know nothing about.

The vicinity of Hong Lim Park: lots of concrete and glass. No solar cells on any of the facades.

To make full use of solar energy, the Singapore skyline will have to change. Currently, following the fashion of the West, our cityscape is dominated by pencil-like skyscrapers. Many of them have steel, aluminium or glass cladding. Out in the suburbs, we have our ubiquitous HDB slab-blocks interspersed with more tower blocks [2]. Most surfaces exposed to the sun are concrete, a material that absorbs solar energy readily, converting it to heat. Only painting our exterior walls white or a light colour prevents them from being intolerable radiators of heat through the night.

The result of the building shapes we have chosen is that they often cast shadows of themselves on other buildings. If we merely clad existing walls with solar panels, we'd find them producing energy at rather low efficiencies since they do not receive solar radiation with sufficient intensity for enough hours of a day.

Another consequence of pencil-like towers and slab-blocks is the high ratio of exterior surfaces to the volume of the building -- while a perfect cube or sphere would have the lowest ratios. With a high ratio of external surfaces, heat penetration into the building is correspondingly greater, whereas, the bulkier the building, the less easily is its interior coolness lost.

Given our environmental conditions and social preferences (our love of atriums), the best building form would be an entire city block, 30 – 50 storeys high, containing a huge atrium, and surmounted by flat, curved or domed roofs. The exterior walls of the 10th floor and up would be clad in solar panels, interfenestrated with windows. The roofs of course, would be solar panels, but still translucent, to let in light. The atrium does not have to be the noisy event spaces that shopping malls generally have, but being larger, could be cool, green parks.

Buildings would turn their backs on the roads and look inward into their atriums. Again, this is nothing new. For a period in the 1970s and 1980s, we built shopping malls that turned inwards, e.g. Centrepoint, Marina Square, Raffles City and Wisma Atria. It was then the fashion in the West, and naturally, we aped it. Then the West changed. They discovered that people liked natural light, particularly the pedestrianised streets, with sidewalk tables and the opportunity for people-watching. So from the 1990s on, Singapore duly aped the West again, with absolutely no consideration for our climate. We started adding outdoor cafes and spruced up our sidewalks only to discover the average Singapore fleeing past them into shopping mall atriums.

The cafe in front of Borders -- a place to get cooked

In front of Borders the bookshop, there's a cafe which should be very popular given its strategic location along Orchard Road. Yet, despite a wide canopy, it's still warm, humid and stuffy. All the concrete from the nearby buildings and sidewalk radiate heat into the cafe, which no amount of canopy-shading can counteract. The few people actually sitting in the cafe when this picture was taken on a 33-degree afternoon were all Caucasians, probably tourists, who don't have any tropical survival skills.

Hot exhaust is a fine way to greet your customers!

Meanwhile, shops in the HDB heartland that were not originally equipped with airconditioning, found they had to install them if they hoped to keep their employees and customers. So they added airconditioners willy-nilly, which cooled the interior of the shops, but at the same time, pumped the heat into the arcades right in front of them, blasting the pedestrians walking by.

In our apartment blocks, many have installed airconditioners, but these pump heat out into the surroundings. The poor family who can't afford airconditioners and have to sleep with windows open, get the resulting heat blown in to his home.

Hot exhaust into your neighbour's bedroom!

One of these days, we're going to look back on this age and wonder how we could be so mad as to live with such an arrangement. Individuals each caring only for his own temperature control is no solution. It's as if we didn't have a municipal sewerage system, and each family tipped his waste into the street and common areas, even as we lived cheek by jowl in an urban environment. Like sewerage, water supply or the power grid, temperature control should one day be a civic concern, with the lead taken by government.

It may have to be publicly funded, or at the very least, written into building codes (with financial incentives) so that private developers gradually add to the city's stock of huge airconditioned spaces open to the public all hours of the day and night.

Something as ambitious as this must be driven by a political decision. But it has its pay-offs. Besides making our city truly unique and comfortable for our own citizens, the R&D can generate intellectual property with market value. Making a city-wide concerted effort to clad buildings with solar cells will create the necessary demand to impart economies of scale to the manufacturing process, kick-starting a new industry with export potential.

If we can't conceive of all that, once again, we have a failure of imagination.

Above, I mentioned a more appropriate building form to serve the objective of public spaces (i.e. open 24 hours, as public as our sidewalks and parks) that are temperature-controlled, and which provide the physical setting for a city that is truly alive and edgy. It is that of a gigantic carton box, perhaps 500 metres on the road frontage, and rising 30, 40 or 50 storeys high. For those familiar with Singapore, think in terms of something the size of Suntec City combined with the Conrad Hotel, the Millenia Walk, Millenia Tower and the central fountain, totalling perhaps 15 – 20 hectares. The entire block would be large enough within its envelope to contain several office and apartment buildings, hotels, shopping malls, pedestrian streets and even a green lung. A large urban village, all within an airconditioned box.

Its roof, in area the size of a small airport runway, and much of its sides would be clad with solar cells. It may have huge chimneys to let the heat out, each chimney larger than a cruise-liner's funnel.

Here is a simple sketch of how one such block may look, and below it, a sectional cut-out, so you can see its interior comprising more buildings, pedestrianised streets and even a green park and a school field within. Not shown (but it should be obvious through necessity) would be underground connections to metro stations, and linkages to neighbouring blocks.

	A huge city block, 500 metres square, 40 storeys high, as a single airconditioned unit
	Within the envelope are multiple buildings, pedestrian streets and a park

It should be achievable, within say, 15 – 20 years, shouldn't it? Will Singapore get there first, or will we be content as mere followers, and roast in the heat until some other city proves it can be done? 

© Yawning Bread