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A s the project progresses, students expand on the basic vapor power cycle and incorporate concepts from course topics, such as superheat, reheat, and regeneration. The design doesn’t come easy. Students struggle with the reality that their design has to meet the needs of the three different entities: the government (me), which may impose regulations or provide incentives; stakeholders (upperclassmen) who have an interest in the plant’s profitability; and the end-users (population of Springfield, Mass.), who want economical energy. Solutions with initial and operating costs are presented biweekly to the stakeholders (upperclassmen) through written reports and meetings. The stakeholders give customer feedback to be implemented in the next design round. Given the number of different entities to satisfy, the students try to consider the needs of both the stakeholder and end-user in their design selection. B ut PBL wasn’t enough. Students still couldn’t see the big picture. I needed course assignments that fostered an entrepreneurial mindset and focused on creating value. Therefore, I structured my course around three main learning outcomes: 1 Students will be able to apply thermodynamic principles to a multi-dimensional problem and generate technical solutions that maximize customer value. 2 Students will develop the skills to carry out an iterative design process. 3 Students will develop the ability to effectively communicate, both in writing and verbally, with their team members and the customer. My students tackle an iterative, team-based design problem. Groups act as small start- up companies competing to build an electric-generating power plant. They gain an understanding of how to apply thermodynamic principles to power plants. Of course, they calculate energy capacity, losses, and efficiencies. But they also creatively find opportunities to improve the value proposition for the end-customers and other stakeholders. Their designs are influenced by economic, socio- political, and environmental factors. T he module starts with students dividing themselves into teams of four. Each team functions as a different company. Teammembers choose a role to play within their company: project manager, financial analyst, public relations director, or system integrator. At this point the classroom is buzzing with excitement as students form their companies, competing for the most creative name. Each company is assigned to a different fuel type such as fossil fuel, nuclear, or alternative energy. Their task is to design and analyze an electric- generating power plant for Springfield, Mass. E nvironmental impact is measured in terms of the method students choose to cool their plant (cooling tower or river) with their pre-defined fuel source (see Figure 2). Providing students with cooling method options and assigning different fuel sources causes them to look into the pros and cons of each, only to find there is no “right” answer. The intent is that students select a cooling method based on customer input. Does their customer prefer a river and not the unsightly towers? If a team doesn’t have a preferred fuel source, what new technologies can they implement to convince the customer they are the best plant? These are questions students learn to ask to stay competitive with their peers. Additionally, the government regulations I impose throughout the module force students to go through multiple design iterations. Typically, these regulations are based upon a customer value, such as environmental impact or performance. I bring examples of recently passed real-world legislation into the classroom. Although students might cringe when new regulations are introduced, policy changes may dictate a redesign. An example regulation is a monthly fine for any company choosing to cool with a river due to the negative environmental impact. Regulations that directly affect budgets become a motivator for students to research new technologies and become more creative in their solutions. As the module unfolds, governmental regulation regarding fuel sources becomes a point of contention among students. This is the most valuable part of the course. Students become up-to-date on recent energy legislation and start to understand the influence of economic, socio-political, and environmental factors on design. For instance, Massachusetts passed a regulation prohibiting coal-fired power plants. Teams using coal were quite upset. They thought I set them up for failure. However, they quickly learned to examine the regulations very carefully. In the end, students surmounted the obstacle by placing their plant in a nearby state, from which they were able to supply electricity to Springfield. Each company is given an initial budget to select components for the power plant (see Figure 1). When developing their technical solution to maximize value, teams must make tough decisions between components that differ in cost and efficiency. Cost is measured through the initial capital required to build the plant and the operating cost represented in Watson/kWh — the class’s specially defined currency. With their starting budget of two million Watsons in hand, students begin investigating existing electric-generating vapor power plants from both an engineering perspective and in terms of societal and governmental needs. Teams can then earn more Watsons throughout the course by completing assignments or doing research into new and innovative technologies used in existing electric- generating power plants. Students measure their plant’s performance in terms of cycle/overall plant efficiencies and total power output. They calculate the cycle efficiency. Efficiencies are defined as the amount of energy or power the cycle produces compared to the amount of energy it consumes. Since the vapor power cycle is just one sub-system of the entire power plant, the efficiencies of the remaining sub-systems (process associated with the fuel source, i.e. combustion, cooling process, cooling tower, and the electric generation process which provides electricity) also need to be considered in the plant efficiency. The total power output is the available energy the power plant will produce for an end-user. These parameters are important. The more efficient the plant, the more power that is produced with less required initial energy. The more power that is produced, the more energy you have to sell to potential customers. DO THE MATH B y the end of the semester, students reported that the project improved learning effectiveness and stimulated the entrepreneurial mindset. Even if student attitudes about thermodynamics were unchanged, the project was motivating. One student commented, “I don’t like thermodynamics or the fact that it’s at 8:00 a.m., but I came to class because we did this project.” In addition to motivating the sleepy student, this module has helped students when interviewing for internships or full-time positions. They often come back and tell me they discussed the power plant project and the interviewer was quite impressed. Usually this positive impression leads to the student receiving the job, as few students understand that technical design is often driven by financial and political parameters. It’s encouraging to know that classroom experiences can help place students at companies that value solving complex, open-ended, iterative problems. The role of the customer is played by upperclassmen, usually senior mechanical engineering students. Students are instructed that their customer, the upperclassmen, will select the power plant design they plan to invest in and “build” at the end of the semester. In this sense, their customer is actually the stakeholder for the power plant but may not be the energy consumer. I play the role of the government, imposing regulations and verifying that designs are up to code. Starting with a basic vapor power plant cycle analysis, the project objective is to maximize the customer’s value. Students learn that four processes make up a vapor power plant cycle: compression through the pump, constant pressure heat in the boiler, expansion through the turbine, and constant pressure heat rejection in the condenser. Since the students are analyzing an actual cycle as opposed to an idealized one, they must also consider the pump and turbine device efficiencies, as well as the combustor and generator efficiencies. Professor O’Neil (right) provides a hands on experiment for understanding the vapor power cycle FIGURE 2: COST IDENTIFICATION OPERATIONAL COST Turbine I Cost 12,500,000 Efficiency 0.76 Pressure (kPa) 3000 Temperature (ºC) Turbine II Cost 13,000,000 Efficiency 0.65 Pressure (kPa) 7500 Temperature (ºC) Turbine III Cost 19,999,999 Efficiency 0.89 Pressure (kPa) 15000 Temperature (ºC) Cooling Type Cost (Watsons) Maximum Flow Rate Inlet Temperature (ºF) Outlet Temperature (ºF) Environmental Fine 0 15,000 46 80 20,000 Watsons/month 0 27,000 40 95 40,000 Watsons/month Cooling Tower 80,000 12,000 50 65 500 Watsons/month COOLING Plant Type Energy Source Cost Source/Leadtime Ec Environmental Fine Fossil Fuel Coal 65 Watsons/ton USA-Appalachia/ days-week 65 Watsons/ton 35,000 Watsons/month Petrol 4 Watsons/gallon USA-Gulf Coast/ weeks 4 Watsons/gallon 33,000 Watsons/month Natural Gas 5 Watsons/thousand ft 3 50 5 Watsons/ thousand ft 3 25,000 Watsons/month Nuclear Uranium 235 60 Watsons/kg Canada/years 60 Watsons/kg 7,500 Watsons/month 30,000 Watsons/ton bi-monthly for storage of nuclear waste Plutonium 239 70 Watsons/kg Canada/years 70 Watsons/kg Alternative Energy Solar — Sun/8 minutes Wind — Variable — Variable I Sun/8 minutes — River COOLING COST Cooling Type Cost (Watsons) Maximum Flow Rate Inlet Temperature (ºF) Outlet Temperature (ºF) Environmental Fine 0 15,000 46 80 20,000 Watsons/month 0 27,000 40 95 40,000 Watsons/month Cooling Tower 80,000 12,000 50 65 500 Watsons/month COOLING River Turbine I Cost 12,500,000 Efficiency 0.76 Pressure (kPa) 3000 Temperature (ºC) 350 Turbine II Cost 13,000,000 Efficiency 0.65 Pressure (kPa) 7500 Temperature (ºC) 450 Turbine III Cost 19,999,999 Efficiency 0.89 Pressure (kPa) 15000 Temperature (ºC) 550 FIGURE 1: BUDGETING 15 14 h plant = h cycle ´h fuelsource ´h cooling ´h electricgeneration h plant = -------------- W netpoweroutput = Q energyfromfuelsource - Q cooling W netpoweroutput Q energyfromfuelsource