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Unformatted text preview: Chapter 16 - Energy Efficiency and Renewable Energy Note the discussion of Iceland’s energy needs and their commitment to become a hydrogen-fueled country by 2060. Technological problems exist, but these initiatives are where we need to go if we are to increase the sustainability of the human species in the next century. Iceland is lucky in that it has abundant geothermal power supplies to partially power the hydrogen fuel cell technology. Other countries have different sources of non-fossil fuel energy that can be developed during your lifetimes as fossil fuels become scarce. One partial solution to energy development that we have talked about in class is to become more efficient in the way we use energy. As you can see in Figure 16-2, we don’t do a very good job of energy efficiency in the U.S., even considering the 41% that is wasted as heat during energy transitions (remember the 2 nd law!). Given the 16% of our energy inputs that end up as useful energy or petrochemicals, that leaves 43% that is wasted by inefficient lights, furnaces, motors, coal and nuclear plants, almost all motor vehicles, and other devices. Add to that wasteful and outdated building designs (including inadequate home insulation) and benign inattention (leaving the lights on when you leave a room, leaving the TV on when you go take a shower, etc.), this waste adds up when you consider we have 300 million people in the U.S., and almost 7 billion in the world. Note that “ reducing energy waste is the quickest, cleanest, and usually the cheapest way to provide more energy, reduce pollution and environmental degradation, slow global warming, and increase economic and national security. ” Can we do it? Of course. Will we do it? If enough people see it as an important move toward sustainability, maybe we will. Note the energy wasted by incandescent light bulbs, cars, nuclear plants, and coal-powered plants. We must do better, and the savings could mean fewer coal-powered plants and reduced CO 2 releases. We have alternatives, although they are often more expensive, but look at the relative net energy efficiencies of heating a house with a nuclear plant versus a passive solar system; this is where your children and grandchildren will need to be in terms of energy technology. Some companies use combined heat and power (CHP) to meet their energy needs, producing two energy sources and in a much more efficient system. We could replace energy- wasting electric motors with more efficient, variable output motors that would save huge amounts of energy. The steel industry could rely more on recycled scrap iron and use new furnace technologies to reduce its worldwide energy consumption by 40%, the cement industry could do the same and save 42%. Why haven’t we done this before? My guess is that since the beginning of the industrial revolution, energy has been cheap. Why spend money increasing efficiency when the resource is cheap and apparently inexhaustible? We need to replace incandescent bulbs with halogen or LED lights...
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- Fall '08
- Solar cell, Energy development, World energy resources and consumption, Fuel cell