Exam (elaborations) TEST BANK FOR Energy Management 8th Edition International Version By Klaus Dieter E. Pawlik (Solutions Manual)

Problem: For your university or organization, list some energy management projects that might be good “first ones,” or early selections. Solution: Early projects should have a rapid payback, a high probability of success, and few negative consequences (increasing/ decreasing the air-conditioning/heat, or reducing lighting levels). Examples: Switching to a more efficient light source (especially in conditioned areas where one not only saves with the reduced power consumption of the lamps but also from reduced refrigeration or air-conditioning load). Repairing steam leaks. Small steam leaks become large leaks over time. Insulating hot fluid pipes and tanks. Install high efficiency motors. And many more 2 Solutions Manual for Guide to Energy Management, International Version Problem: Again for your university or organization, assume you are starting a program and are defining goals. What are some potential first-year goals? Solution: Goals should be tough but achievable, measurable, and specific. Examples: Total energy per unit of production will drop by 10 percent for the first six months and an additional 5 percent the second half of the year. Within 2 years all energy consumers of 5 million kilojoules per hour (kJ/h) or larger will be separately metered for monitoring purposes. Each plant in the division will have an active energy management program by the end of the first year. All plants will have contingency plans for gas curtailments of varying duration by the end of the first year. All boilers of 25,000 kg/h or larger will be examined for waste heat recovery potential the first year. Introduction to Energy Management 3 Problem: If you were a member of the upper level management in charge of implementing an energy management program at your university or organization, what actions would you take to reward participating individuals and to reinforce commitment to energy management? Solution: The following actions should be taken to reward individuals and reinforce commitment to energy management: Develop goals and a way of tracking their progress. Develop an energy accounting system with a performance measure such as kJ/m2 or kJ/unit. Assign energy costs to a cost center, profit center, an investment center or some other department that has an individual responsibility for cost or profit. Reward (with a monetary bonus) all employees who control cost or profit relative to the level of cost or profit. At the risk of being repetitive, note that the level of cost or profit should include energy costs. 4 Solutions Manual for Guide to Energy Management, International Version Problem: Perform the following energy conversions and calculations: a) A spherical balloon with a diameter of three meters is filled with natural gas. How much energy is contained in that quantity of natural gas? b) How many Joules are in 550 cubic metres of natural gas? How many GJ in 2,000 litres of #2 fuel oil? c) An oil tanker is carrying 3,000 litres of #2 fuel oil. If each litre of fuel oil will generate 3.3 kWh of electric energy in a power plant, how many kWh can be generated from the oil in the tanker? d) How much hard coal is required at a power plant with a heat rate of 10 MJ/kWh to run a 6 kW electric resistance heater constantly for 1 week (168 hours)? (One tonne of hard coal conttains 25 GJ of heat.) e) A large city has a population which is served by a single electric utility which burns hard coal to generate electrical energy. If there are 500,000 utility customers using an average of 12,000 kWh per year, how many tonnes of coal must be burned in the power plants if the heat rate is 10.5 MJ/kWh? (One tonne of hard coal contains 25 GJ of heat.) f) Consider an electric heater with a 4,500 watt heating element. Assuming that the water heater is 98% efficient, how long will it take to heat 200 litres of water from 20 degrees C to 60 degrees C? Introduction