This week’s readings offered many examples on how to both spread renewable technologies as well as strike at the core of energy issues by reducing the overall energy load. These are very important topics that need to be discussed and implemented all over the world to combat both energy shortages as well as global warming.
There are many ways to implement renewable energies. These include the standard examples of wind farms and photovoltaic arrays but also include much more traditional processes such as cogeneration and district heating and cooling. The prior has already gained widespread attention but cogeneration is somehow missed by many when the discussion of alternative energy comes into play. Cogeneration is an extremely important process and involves taking the waste heat from electric generation and pumps this heat out to the surrounding areas to be used to heat homes and hot water. This heat is otherwise wasted which results in the standard power plant efficiency of around 30%. A 30% efficiency means that nearly ¾ of the fuel’s energy is lost to the environment and nothing productive has come of it. Though typical measures of improving the combustion cycle may increase this efficiency, no amount of reheating or superheating will bring this efficiency to anywhere even close to 50%. The reason is that most of this energy results in a gas or fluid that is too cold to produce any extra electricity. Cogeneration, however, has found a way to take advantage of this waste heat. Though the fluid is too cold to produce any more electricity, it is still very hot in people standards where a hot shower is no more than 110 degree F. Cogeneration plants run the waste fluid through a heat exchanger which removes a large amount of it’s energy. This heat is transferred over to a water or steam line where it can then be piped out to the surrounding homes and businesses. This allows the heat which is worthless in terms of electricity production to supplement all of the heating requirements of the consumer and by finding a use for this waste heat, efficiencies can more than double reaching 80%-90%. Cornell’s COGEN plant has been achieving around 80% efficiency and will approach 90% after it’s upgraded COGEN turbines are completed.
This past example only shows one half of the energy issue which is the generation, but does nothing to combat the actual energy usage. A number of programs around the country and world have started up to offer incentives to energy efficiency projects. Heating and cooling account for a large part (up to 50%) of the energy usage in buildings so many programs have been started which help pay for improvements in this area. These come in the form of insulation improvements, higher efficiency windows, and gas fired boilers to supplement electric heater are widely seen. It is important that these programs continue. Many of the people who incur the highest utility rates reside in lower quality homes where windows and walls are drafty and much of the heat is lost to the environment. Because these lower quality homes are often found in lower income areas, a huge chunk of the resident’s income goes to keeping his family safe. This coincides with the idea of “economic multipliers” which addresses the idea that utility rates suck an enormous amount of money out of the community and further it’s economic disparity. These lower economic places should be the focal point of energy efficiency programs so they can live more comfortably and spend less on their energy bill giving them the freedom to reinvest these savings in their local community.
There are a wide variety of ways in which to reduce fossil fuel dependence and combat global warming. Though I have only addressed a few here, it is vital to take advantage of any opportunity to improve efficiency and failure to do so will only further our problems.
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