Unit 10: Energy Challenges // Section 15: Increasing End-Use Efficiency of Energy and Materials
Thirty years of fluctuating world energy prices since the Arab oil embargos of the 1970s, as well as growing concerns about the environmental impacts of producing and using energy, have made it increasingly clear that "more of the same" is not a sufficient basis for national energy planning. Many of the best world oil and gas resources are being fully exploited, and resource depletion is making the remaining supplies more expensive. Some oil experts contend that world oil production will peak in the near future, although others strongly disagree and argue that technology improvements will continue to make new reserves exploitable. We can expand energy supplies by using alternative sources and technologies that usually have lower environmental impacts, but this typically costs more until new sources are fully commercialized. The same is true for some of our important material resources.
When resources become scarce, we can benefit from learning to get more services from a given flow of energy or stock of material. For example, we can design cars that are stronger but weigh less than today's models and get more miles per gallon, buildings that require less energy per square foot to heat and cool than current structures, refrigerators that require less power per cubic foot of interior volume, lights that deliver more illumination for each kilowatt-hour of electricity they consume, and manufacturing processes that use less energy to make a given array of products.
Industrialized and developing countries alike have greatly increased their energy efficiency in recent decades. The United States doubled the overall energy efficiency of its economy between 1970 and 2005. That means that this country was extracting twice as much real gross domestic product from each unit of energy flowing through the economy in 2005 as it did 35 years earlier. There are many areas in which we can continue and accelerate these trends by using energy and materials even more efficiently.
Investments into research and development of end-use efficiency challenges often pay for themselves many times over in resulting savings. Figure 24 shows representative estimated savings from energy efficiency upgrades in a home located in an average U.S. climate and equipped with standard appliances.
Figure 24. Profitability of energy efficiency upgrades
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Source: © Lawrence Berkeley National Laboratory. Environmental Energy Technologies Division.
When a refrigerator saves a kilowatt-hour of electricity or an efficient car saves a liter of fuel, that energy is available for use elsewhere in the economy. This means that improving end-use efficiency is like finding a new supply of energy. It is often cheaper, faster, and cleaner to reap gains from end-use efficiency (sometimes referred to as "negawatts," to connote energy that does not have to be produced) than to expand energy supply through exploration and drilling. Similarly, investing in recycling programs, better product design, and longer product lifetimes, we can reduce our need for newly-mined minerals.