Energy: Some Basics

Energy Basics Energy: the ability to do work Potential Energy: energy that is stored Kinetic Energy: energy of motion - All energy is either potential or kinetic, or a combination.

Laws of Thermodynamics First Law: Energy can neither be created nor destroyed, only changed in form. Second Law: Energy always goes from a concentrated, highly usable form to a less concentrated, less usable form. The LEAST concentrated form of energy is HEAT.

Energy Efficiency First Law Efficiency : The amount of energy without any consideration of the quality of availability of the energy. Work Energy Delivered/ Work Energy Input

Second Law Efficiency: How well matched the energy end use is with the quality of the energy source. For example: To heat your house from 65 to 68 degrees, you need only 3 degrees within the house, but we burn gas or oil at almost 1500 degrees to release a small amount of heat to warm the house. Most of the heat from the burning fuel is lost as waste heat, which goes up the chimney. The ratio of the minimum amount of work or energy required to perform a task to the amount actually used.

In other words: 1)Nothing is ever 100% efficient 2)The more closely matched the end use is to the amount of energy consumed, the closer we come to 100% efficiency. EX: A water heater that only heats water to 120 degrees, and no higher is MUCH more efficient than one that boils water for hot water.

Total Energy Consumption in the United States

Energy Consumption by Sector

Energy Conservation, Increased Efficiency and Cogeneration Conservation: getting by with less demand for energy. Cogeneration: a number of processes designed to capture and use waste heat rather than simply to release it into the Atmosphere. Energy Efficiency: designing equipment to yield more energy output from a given amount of input energy.

Energy Policy Hard Path vs. Soft Path –Hard Path: finding greater amounts of fossil fuels and building larger power plants –Soft Path: involves energy alternatives that emphasize energy quality and flexibility Energy for Tomorrow Integrated, Sustainable Energy Management –Integrated Energy Management: no single energy source can provide all the energy required by the world –Sustainable Energy Management: provides reliable sources of energy without causing serious harm, all while ensuring that future generation inherit a fair share of Earth’s resources