WWPB

Peter Behnke

Sustainability Problems

Why Worry? Inefficiencies in Electrical Generation

Nearly everyone in the United States uses electricity on a daily basis. In order to meet the demand for power, there are power plants scattered across the US and Canada that are in constant production mode. What’s worse is the fact that as technology improves and population increases, there will be an ever growing demand for reliable power. But why is this problematic for individuals? On a whole, the power generation industry is a leading cause of air pollution across the world. This is because the current methods of generating electricity result in the burning of vast stocks of fossil fuels. Annually, the United States power sector is emitting approximately 2.8 billion tons of carbon dioxide. This makes the US power industry number 1 in the world rankings in terms of pollution, yet most other developed countries are close behind. It is estimated that the social cost of 1 ton of carbon dioxide is between $8 and $100. (Science Daily, 2007). This does not even take into account other harmful pollutants being released into the atmosphere, some with even more catastrophic effects. Yet individuals still want to have access to electricity, so how can we potentially fix the problem? It seems that part of the solution is to improve the efficiency of the power grid. This, in conjunction with other measures such as using less electricity, can drastically decrease the amount of pollutants entering the environment. In order to look at the efficiency of the power grid, one must start at generation and then work their way down until they reach the consumer level. For generation, the maximum amount to total energy converted to electricity is ~60%. This 60% target applies to gas turbine technologies, whereas traditional coal plants operate at only 35% efficiency (ABB). Technologies such as nuclear and hydroelectric generation do not apply in this calculation. Even at 60% efficiency we are still wasting a large majority of a limited resource, which will eventually come back to hurt us in the end. I will discuss potential remedies to these generation inefficiencies later. Another area in which there are substantial inefficiencies is in the transmission and distribution of electricity. On average, there are 6-8% in losses due to transmission and distribution yearly. For example, in the year of 2005, there was a total of 3.9 billion MWh of electricity generated with 3.6 billion sold to companies and consumer. There was also 239 million MWh lost due to transmission and distribution, totaling 6.1% (ABB). This leads one to question where these inefficiencies come from. A majority of these losses come from resistance, which converts the electrical energy into heat. Other sources of inefficiency come from interference between transformers and congestion charges. When transformers change the voltage of electricity they create a field which can potentially interfere with other fields around it reducing its overall strength, this is how losses come about from interference. Congestion charges happen when there is an excess load put on a system. This causes safety measures to reroute energy flow or drop power to certain locations (ABB). From these two sources alone one could estimate the potential inefficiencies to total ~33-68%. For a reasonable estimation, I would choose to rate our generation and distribution system at 50%. That means that the US is putting 1.4 billion tons of carbon dioxide into the atmosphere that is unnecessary. This leads me to believe that the world as a whole need to improve this system in order to protect our environment. The major way that we could improve would be to improve generation efficiency, as it is the larger of the two inefficiencies discussed. The EPA is already enacting policies that make the most inefficient facilities upgrade, as well as promote new technologies that are inherently more efficient. Due to this, I would like to discuss ways to improve transmission and distribution inefficiencies as this is more of an untouched problem. The transmission and distribution of electricity requires both voltage and frequency levels to be at intervals of 110 volts and at 60 Hz to ensure that the consumers appliances are not harmed. This means that you must have generation plants outputting at those specifications, as well as a nearby facility to “boost” the voltage back up after it travels extended distances. These facilities are called reliability must-run plants. They are generally older plants (read: less efficient) that are located closer to the populous. They also have little room for upgrade due to space, reliability, and health concerns (ABB). Therefore these plants are always running to ensure that consumers get proper power delivery, continuously putting more pollutants into the air. A remedy for this would be to install combined generation of heat and electricity plants in new building in cities. These plants could replace the must-run plants with more efficient gas turbines, as well as remove inefficiency by converting the waste heat to hot water and heat for the building they are installed into (Pepermans). This would eliminate the more inefficient plants as well as partially remove an externality in waste heat. Another problem is the fact that most large scale production facilities are located a substantial distance away from the towns and cities that they are powering. This means that companies must transmit the power, generally in the form of high voltage cables. These require the voltages to step up through a series of transformers, reducing the amperage and therefore reducing loss to heat. Afterwards they must step the voltage back down so they can distribute it to the consumer. This stepping up and stepping down process is inefficient due to heat generated as well as interference between transformers. A potential remedy to this solution comes in the form of distributed generation. Distributed generation is an all-encompassing term that refers to any generation that is away from a large production facility (Ackermann). This means that it can include individual wind turbines, micro turbines, natural gas turbines, and solar panels. The concept for distributed generation can be seen today with personal solar panels and cities funding micro turbines, but it can also occur on a much larger scale. The benefit of these projects is that there is no need for voltage changes, as the power is being generated where it will be used. Similarly, as more power is required, more distributed generation facilities can be activated and therefore meet demand. This solves a problem for most production facilities because they generally make extra electricity just in case someone has a much larger demand (Pepermans). The only issue is that these plants are still in their infancy and therefore have many issues that need to be sorted out. A few examples are; inconsistent voltages, inconsistent frequencies, feedback power problems, and the need to expand safety systems to ensure proper power management (Ackermann) Overall I feel as if distributed generation facilities are the way of the future because they eliminate many of the inefficiencies that plague the power industry today. With the elimination of these inefficiencies we will pollute the environment less, opening the possibility of a much nicer planet.

Works Cited Ackermann, Thomas, Goran Andersson, and Lennart Soder. "Distributed Generation: A Definition." //Elsevier//57.3 (2001): 195-204. //ScienceDirect//. SciVerse. Web. 13 Sept. 2012. <[]>. Pepermans, G., J. Driesen, D. Haesekdonckx, R. Belmans, and W. D'haeseleer. "Distributed Generation: Definition, Benefits and Issues." //Elsevier// 33.6 (2005): 787-98. //ScienceDirect//. SciVerse. Web. 13 Sept. 2012. <[]>. “Energy Efficiency in the Power Grid.” ABB Inc. 2007 < []>. Center for Global Development. "Carbon Dioxide Emissions From Power Plants Rated Worldwide." ScienceDaily, 15 Nov. 2007. Web. 14 Sep. 2012. <span style="background-color: #ffffff; font-family: 'Times New Roman',serif; font-size: 12pt;"><[]>. <span style="background-color: #ffffff; font-family: 'Times New Roman',serif; font-size: 12pt;">