Energy Consumption in the City
Urban Crossroads #28
Jordan, an importer of an average of 110,000 barrels of oil per day, needs to think seriously about developing energy conservation strategies. Oil prices are reaching exorbitant levels, and there is general agreement that prices will remain high. This is not only because of political instabilities affecting one oil-producing country or the other, but also because of the rapidly increasing energy consumption (and consequent oil imports) taking place in the world's two most populous countries, China and India, both of which are experiencing robust economic growth.
It is in the city where most energy consumption takes place. A great deal of that consumption is the result of transportation needs. Also important are the heating and cooling requirements in buildings. There are other major sources of energy consumption, such as industrial production, but this falls beyond the scope of this article.
In the case of transportation, the solutions to reducing energy consumption are well-known. The most important is developing efficient, high-quality public transportation systems and to encourage their widespread use. It clearly is more energy-efficient to rely on transportation vehicles such as buses, which can transport dozens of people, instead of cars, which in many cases are used to transport only one person, the driver. A less acknowledged source of energy conservation is telecommuting. Accordingly, information would travel through high-speed telecommuting networks, without requiring someone to physically transport the information, as with a courier or messenger. The potentials for telecommuting are boundless. They include allowing people to work from their homes and to communicate with colleagues through telephones and the Internet. Telecommuting also makes it possible to buy items through the Internet, such as plane tickets and hotel reservations, renewing all types of subscriptions, whether magazines or insurance, as well as carrying out various transactions, such as banking or governmental transactions (paying fees and taxes or renewing one's automobile registration). Each of these various purchases or transactions requires a round trip or more for the person involved, thus wasting time and energy, and contributing to traffic congestion. If carried out through the Internet, these transactions in contrast may be done from the comfort of one's home. Even buying items such as groceries over the phone or the Internet can help lower fuel consumption. Instead of having each shopper drive to the supermarket (which increasingly is replacing the neighborhood grocery store in Amman) for the mundane task of buying groceries, we would rely on a relatively small number of delivery vehicles that bring groceries to the doorsteps of clients.
Another source of energy consumption is the heating and cooling of buildings. Many of us feel the pinch of heating costs whenever we fill up our heating fuel tanks during the winter. An increasing number of people in Amman are obtaining air-conditioning systems, which can result in excessive summer electricity bills. We should keep in mind that temperatures in a building depend a great deal on how the building is designed and built, as much as on the use of mechanical heating and cooling equipment. Unfortunately, as heating and cooling equipment became widespread over the past few decades, both members of the building industry, as well a the owners and users of buildings have become less concerned about the heating efficiency of their buildings.
The energy efficiency of buildings partly depends on solutions such as the use of insulation materials in walls and roofs, double or triple glazing for windows, and renewable energy sources as with solar panels. However, a building's consumption of energy also greatly depends on issues such as the number of windows it contains, the size of those windows, and the direction they face. For example, research has shown that in climatic regions such as ours, southern windows that measure in area around 10% of the rooms they serve provide optimal solutions for energy efficiency. Southern openings are encouraged because it is relatively easy to block the high summer sun from entering southern windows through the use of canopies or through deciduous trees, but is easy to allow the low warm winter sun to enter them. Windows facing other directions should be greatly curtailed. Western windows are the worst offenders since they face the cold winds during the winter, and the hot sun during summer afternoons. In the case of eastern windows, it is difficult to block the low hot summer sun during the morning hours. On the other hand, northern windows are a source of heat escape during the winter. All this means that buildings, and subsequently the plots on which they are located, preferably should have adequate southern exposures. The subject of designing buildings for energy efficiency is far more involved than presented here, and these comments only are intended to provide a basic overview of it.
The proper use of landscaping also can play a very important role in increasing the energy efficiency of buildings. Placing deciduous trees around a building allows the warm sun to enter it in winter, but blocks the hot sun in summer, when the leaves grow back on the trees. Evergreen trees are effective windscreens and are very suitable for western exposures since they hinder the cold westerly winds. They also serve to keep out the hot afternoon summer sun. In addition, greenery reduces the reflection of heat from surrounding surfaces into the building, and cools down the surroundings by drawing heat from the air through the transpiration process.
Jordan's oil purchases constitute the largest part of the country's imports (618.8 JD million, totaling 13.7% of total imports during the first ten months of this year). If we are to control the amount of imported oil, we need to rethink issues ranging from transportation to the energy efficiency of buildings. Even small steps at this stage will bring about significant results, and we should start sooner than later. The benefits not only will be lower energy bills, but will include other issues such as limiting sources of air pollution and traffic congestion.
December 9, 2004