Energy. It is generated, consumed, and expelled. Our cities have a constant appetite for it.
So how could that kind of consumption of power and fuel ever be sustainable?
Gerhard Schmitt, Director of the Singapore ETH Centre, said: “A sustainable city is a city able to survive over decades and centuries which really works well. It’s a city where different flows, flows of material, flows of goods, work well, and in which also immigration and emigration are sustainable. It’s not interrupted, on the contrary, it’s continuing and getting better and better.”
Skylines and skyscrapers in a city that are built to impress consume an impressive amount of energy. Rani Virdee, Asia Pacific Managing Director of The CarbonNeutral Company, says this poses a problem for sustainability: “If we’re looking at megacities developing and developing in a sustainable way, that’s quite a challenge today. Because we are developing these cities using fossil fuels, so there’s an enormous amount of embodied energy in these buildings that we see around us.”
Singapore is one of the many world cities facing the challenge of cutting its carbon footprint. The first step is to cut energy use – to do more with less.
A housing development in Punggol is a test-bed for new ideas. The buildings face towards the wind and away from the sun. Natural ventilation is favoured over air conditioning, and rooftops carry tiles to collect rainwater and protect against the sun. On one block, plants are tested to see how they can help insulate against the heat.
Alan Tan, the Deputy Managing Director of HDB Building Research Institute, told us: “One of the benefits that we get from this kind of greenery is that it helps to reduce the ambient temperature by as much as two degrees celsius. Even on the surface of the roof itself, as compared to the concrete surfaces, it can reduce the surface temperature by as much as 15 degrees celsius. So this helps to cool the living environment for the residents in our precinct.”
Energy efficiency can bring significant savings, but the energy still has to come from somewhere. What kind of potential is there for solar power in a city like Singapore?
According to Professor Joachim Luther from the Solar Energy Research Institute of Singapore, getting all energy from solar would not be possible: “It is quite simple to say that Singapore would produce about 15 percent of energy from solar energy. I think that in middle and long term, Singapore would be able to produce about 30 percent of energy needs from solar energy. We couldn’t produce 100 or even 50 percent because there isn’t enough land.”
Solar is still in its infancy in most cities. One of the reasons is that without state subsidies photovoltaics are more expensive than fossil fuels.
At this research laboratory at the Solar Energy Research Institute of Singapore, Professor Luther says the scientists are working on efficiency to try to overcome that obstacle: “Today we have solar modules produced by industry that are around 20 percent efficient. So 20 percent of the light is transformed into electricity. Of course it is possible to upgrade this by a few percent with the silicone technology of today.”
It is unrealistic to imagine a city relying on renewable energy anytime soon. Some are promoting carbon offsets as a way of supporting clean energy projects in order to compensate for greenhouse gas emissions.
However, it is not always an easy sell, according to Rani Virdee from The CarbonNeutral Company: “My personal feeling here, for Singapore, is that we still need to do an awful lot of education and raise awareness, and that happens through a whole multitude of activities. I think there’s a misconception amongst businesses that implementing a carbon management programme is going to cost a lot of money, and it doesn’t, it actually saves money.”
The world’s cities are growing, and with it their demand for energy. Nowhere is that more apparent than in Asia. Here developing clean energy has become a fresh focus of attention says Gerhard Schmitt:
“Within a five or six hour flight of Singapore, we will have more than a billion people living in cities which still don’t exist in the coming years. We have to assure that these cities are being planned sustainably, and the cities that exist today must be rebuilt to be sustainable in the long term.”
It is clear that the enigma of sustainable growth and clean energy is a significant problem that is far from being solved.