The Habitable PlanetHabitable Planet home page

Unit 10: Energy Challenges // Section 1: Introduction



Error - unable to load content - Flash


Industrialized nations rely on vast quantities of readily available energy to power their economies and produce goods and services. As populations increase in developing countries and their citizens demand better standards of living, global energy use will continue to rise, with developing nations accounting for a growing share of total world demand (Fig. 1).

World marketed energy consumption, 1980–2030

Figure 1. World marketed energy consumption, 1980–2030
See larger image

Source: International Energy Outlook. © 2006. United States Energy Information Administration.

Today most of the world's energy is derived from fossil fuels, which are non-renewable resources available only in limited supply. In contrast, many alternative sources of energy, such as wind, solar, and hydropower, are renewable resources because their supplies are refreshed faster than humans consume them. Human society has profited from exploiting energy sources, particularly since energy use became much more efficient during the Industrial Revolution. We are now deeply dependent on reliable, cheap sources of energy. However, it is important to note that energy consumption does not directly improve the human condition. Rather, what matters are the services that we generate using energy.

"Customers don't want lumps of coal, raw kilowatt-hours, or barrels of sticky black goo. Rather, they want the services that energy provides: hot showers and cold beer, mobility and comfort, spinning shafts and energized microchips, baked bread and smelted aluminum. And they want these 'end uses' provided in ways that are secure, reliable, safe, healthful, fair, affordable, durable, flexible, and innovation friendly."

Amory B. Lovins and L. Hunter Lovins, "Mobilizing Energy Solutions," The American Prospect, January 28, 2002

Modern societies also consume vast amounts of material resources, including metals, minerals, stone, chemicals, and fibers. In most cases, these materials are abundant enough that they can be considered either renewable or available in such quantities that we will not soon deplete them. The main concerns associated with material resources, therefore, are generally the costs and environmental impacts of extracting, transporting, and refining them.

Scientists who study energy and material resources seek to understand what types of resources are available and where they can be found, and to develop new technologies for locating, extracting, and exploiting them. Discovering new supplies and using more energy and materials is one way to derive more benefits. But we also can use these resources more efficiently, so that we obtain a rising amount of service from a constant level of inputs. Over the longer term, scientific and technological advances may enable societies to substitute new energy sources and material stocks for old ones. This typically happens when new resources perform as well as or better than current options and produce fewer negative impacts, such as pollution or health and safety risks.

But changing from one resource type to another involves more than simply discovering a new mineral deposit or developing a new technology. It also means altering the systems that produce, process, and distribute these resources. For example, major commercial energy fuels like coal, natural gas, and uranium are mined, cleaned, processed, refined, and delivered through complex, multi-stage systems that represent billions of dollars in infrastructure investments and complicated logistical interconnections (Fig. 2). Energy facilities typically operate for 30 to 50 years, so they cannot change to different resource or technology mixes overnight. Retiring them prematurely to replace them with something "better" is very costly even if the new plants are not more expensive than the old ones.

Offshore oil drilling platform, Gulf of Mexico

Figure 2. Offshore oil drilling platform, Gulf of Mexico
See larger image

Source: © United States Government Printing Office. Materials Management Service.

This unit describes the main energy sources available or under study today to meet world demand in the current century. It begins with fuels that have been commercialized and are in use on a large scale, including conventional fossil fuels (coal, oil, and natural gas) and nuclear power. We then consider alternatives such as non-conventional fossil fuels, various renewable energy sources, and hydrogen energy. As we will see, the viability of conventional and alternative energy resources depends largely on developing new technologies that will harness them more efficiently while mitigating their harmful environmental consequences—especially their contributions to air pollution and global climate change.

This unit also surveys major uses of non-fuel mineral (material) resources and their environmental impacts. It concludes with a discussion about using resources efficiently as a way to save money, extend limited supplies, and reduce environmental damages.

top of page

© Annenberg Foundation 2014. All rights reserved. Legal Policy