Human Energy Needs
Our energy consumption has led us to develop new energy sources and technologies. In a century, liquid fuels and electricity have improved our standard of living and provided us with more mobility than people in any other era. This section reviews our human energy needs, how we currently meet them, and what the future may have to offer.
essential for all we do as individuals and as societies. Energy production,
use, and distribution also cause some of the most pressing environmental
problems. Figure 6 shows the overall picture of human energy needs, the
ways in which we meet our energy needs, and the impacts.
Although industrialized countries use the most energy at present, newly industrialized countries are increasing their rate of use. Figure 7 graphs the projected energy needs of industrialized countries, developing countries, and Eastern Europe and the former Soviet Union. Many environmental and economic issues arise from the escalating energy use all over the world. Understanding the science and technology driving the energy system enables us to better understand our relationship to the environment.
Energy Use and Sources - Data
The factors that affect energy use most are the level of industrialization, the climate of the region, and the population. These factors are not independent of each other. All of these factors influence energy choices, production, distribution, and usage. The average use of energy per person in different countries varies widely. Table 3 highlights world energy consumption for electricity generation by region and fuel source. It is evident in these tables that industrialized countries use more energy.
Information describing our energy use often can be evasive. Figure 8 shows the main heating fuels the U.S. uses for residential home heating. Electricity use for heating is on the rise; however, electricity is not a direct fuel source like the others in this figure. It is a form of energy. Different sources, such as coal and uranium, are used to generate electricity. Therefore, if electricity use is on the rise, the use of coal and uranium are also on the rise.
We are all affected by and pay for the life cycle of electricity. As end users of electricity, understanding the process of electricity generation gives a clearer picture of what you are paying for and helps in your decision making as a consumer.
as an Energy Sector
for transportation is the least efficient use of fossil fuels. The automobile
loses far more energy than it uses. As shown later (in the Energy Transformation
section), for every 20 gallons put into a car we only get about 2 gallons
worth of actual work. The rest is dissipated as heat. The other inherent
inefficiency is in the fact that to move one person, we have to spend
energy moving over a ton of extra material (the automobile itself).
Use of crude oil is escalating as developing countries emulate industrialized mobility. Figure 8 graphs the use of crude oil for transportation needs. This increase in oil consumption specifically for transportation not only impacts the environment, it will deplete the limited oil reserves in the earth's core. Increased consumption of oil for transportation could also affect a variety of industries (i.e. plastics) which in turn affects the economy.
A review of the science supporting our current energy systems can be found in the section "Science Notes."