The energy intensity—that is, the energy input per dollar of output—of the global economy is declining, and recent decades have seen continuing improvements in energy efficiency. Yet these encouraging developments are being offset by an ever-increasing level of consumption in countries such as Pakistan.
Energy consumption levels in East Asia tended to grow faster than those in South Asia despite being higher initially. Between 1980 and 2001, South Korean and Taiwanese citizens’ per capita consumption expanded an average of 6.7% and 5.1% per year. Pakistani per capita consumption grew 2.5% during the same period.
Everything we consume or use—our homes, their contents, our cars and the roads we travel, the clothes we wear, and the food we eat—requires energy to produce and package, to distribute to shops or front doors, to operate, and then to get rid of.
Most surprising is the dramatic surge in energy use in Pakistan. Compared with just 10 years ago, for example, Pakistanis are buying more cars, bigger homes and more appliances. Still, the average American consumes five times more energy than the average global citizen and nearly 20 times more than the average Pakistani.
Energy Consumption in Pakistan is rising fast. In 2002 it was 1.8 quadrillion Btu (0.44% of world total energy consumption) and Per Capita Energy Consumption was 12.2 million Btu (vs. U.S. value of 339.1 million Btu). Petroleum use alone has quadrupled since 1970. Current trends in energy use simply must not sustain.
Today, transportation is the world’s fastest-growing form of energy use, accounting for nearly 30 percent of world energy use and 95 percent of global oil consumption. Even relatively small shifts in transport choices have significant impacts. Only 0.5 percent of the total distance people travel each year is done by air, yet planes use up about 5 percent of transportation energy.
But the most significant driver of rising energy consumption for transportation is growing reliance on the private car. Many countries have devoted significant resources to public transport while discouraging the use of private vehicles. In Japan and Europe, much of the investment in transportation infrastructure focuses on passenger trains and transit systems. Today nearly 92 percent of downtown Tokyo travelers commute by rail, and the Japanese do only 55 percent of their traveling by car. West Europeans now use public transit for 10 percent of all urban trips, and Canadians for 7 percent, compared with Americans at only 2 percent.
Congestion charges on vehicles entering city centers, combined with investments in public transit, can also reduce car use and pollution. In London, in response to a toll enacted in early 2003, traffic levels dropped by an average of 16 percent in the first few months, and most former car users began commuting by public transit.
As homes become bigger, each individual house has more space to heat, cool, and light, as well as room for bigger and more appliances. Home appliances are the world’s fastest-growing energy consumers after automobiles, accounting for 30 percent of industrial countries’ electricity consumption and 12 percent of their greenhouse gas emissions.
Yet the same needs could be met with far less energy. Technologies available today could advance appliance efficiency by at least an additional 33 percent over the next decade, and further improvements in dryers, televisions, lighting, and standby power consumption could avoid more than half of projected consumption growth in the industrial world by 2030.
There are extreme differences in the energy intensity of manufacturing industries from one country to another. In the early 1990s, the Japanese and Germans used less than half as much energy per unit of output in their heavy industries as Canadians and Americans did, due primarily to differences in energy prices. Japan, South Korea, and countries in Western Europe have the most efficient manufacturing sectors, whereas Pakistan is among the least efficient.
In the cities, widespread use of low-quality fuel, combined with a dramatic expansion in the number of vehicles on Pakistani roads, has led to significant air pollution problems. A hopeful trend is that Pakistan has become the third-leading country in the world to use compressed natural gas (CNG) to fuel vehicles. Currently, government vehicles are being converted and soon over 100,000 taxi that have been using LNG will change to CNG. Although Pakistan's energy consumption is still low by world standards, lead and carbon emissions are major air pollutants in urban centers such as Karachi, Lahore, and Islamabad.
The amount and type of energy we consume is a result of two kinds of choices: those we make as a society and those we make as individuals and families. Through subsidies, taxes, standards, and other measures, government policies have a direct impact on energy supplies, demand, and the efficiency of our homes, appliances, cars, and factories. In Denmark, where the tax on auto registrations exceeds a car’s retail price, and where rail and bike infrastructure are well developed, more than 30 percent of families do not even own cars. And where governments or companies subsidize public transit, people are more apt to commute by bus or subway than by car.
Government policies affecting the price of energy are among the most important, as energy prices are among the fundamental factors determining a nation’s energy intensity. Countries with higher energy prices—like Japan and Germany—also have lower energy intensities, while those with lower prices are generally quite energy-intensive, such as the United States for gas and oil, Australia for coal, and Scandinavia for electricity.
Political will and effective, appropriate policies are essential for driving change. Through taxes and subsidies, regulations and standards, and investments in infrastructure, government can influence how, where, how much, and what form of energy we use. But we as consumers are not powerless bystanders. Ultimately, it is consumers who choose what to buy and how to use it, and thus it is consumers who can drive change. (www.asifjmir.com)
Traditional Control Systems
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Traditional Control Systems are based on setting standards and then
monitoring performance. These systems include three categories of controls:
diagnostic ...
10 years ago
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