1. Program Requirements Alternative Energy Supplement Design Requirements Problem Statement Testing Economic Analysis Energy System Program Requirements Calculate net present worth of each system Calculate break even year Account for changes in energy usage Account for cost increase of energy Include loan options Estimate system production Determine optimal system User friendly interface Program Testing User interface testing Sanity checking for valid user inputs Verify economic analysis results by ….independent calculations Wind speed probability distribution -Weibull shape and scale parameters -Compare with Rayleigh distribution Vertical wind speed profile -Compare with Iowa Energy Center System Testing Pre-installation Power quality Power usage Post-installation Track financial savings Actual power output Proper Installation -Grounding -Automatic disconnect if utility power is lost -Structural stability -Starting and stopping of turbine Monitoring system performance Reduce client’s energy bill Use alternative energy systems -Wind -Solar Projections -Energy use -Energy production -Future building plans Determine mode of operation Economic analysis program Modes of Operation Stand alone system -Independent of the grid -Always meets full load -Stores energy Primary -Connected to grid -Provides more than half of consumed energy Backup -Connected to grid -Provides less than half of consumed energy No change Client: Mary Elizabeth and Colin Chinery Advisors: Professor John W. Lamont and Professor Ralph Patterson III Team Members: Matthew Kelly, Aaron Kulow, Daniel Rathe, and Joshua Riley Project website: http://seniord.ece.iastate.edu/dec0704 System Requirements Operates -30 to 120 degrees F 60 Hz Automatic Protection from back- …feeding to grid during an outage Package deal -One contractor does all installation work -All system components must be compatible -Available for installation in Iowa Wind Power Calculation Input Page Output Page X = Dec07-04 The input page is part of the user interface where the user is able to enter estimates for future power usage and costs. A list of systems and towers are available for the user to analyze. Data for financing the system is also entered on this page. The information is then run through the program calculations to return the output page below. The output page displays economic savings and energy production values for the selected system. The “Cost vs Time” graph displays the overall lifetime costs of installing and not installing a system. The payback period is at the intersection of the two lines. The “Revenue” graph shows the difference between the two options. The system starts to save the client money when the graph reaches a positive value and the payback period is when the line crosses zero. The “Monthly Energy Output” chart simply visualizes the table of energy output to show the client production of the system. The “Cost Comparison” graph shows the net costs of each option as well as the net present worth of purchasing the selected system. The wind power calculator uses the Rayleigh probability distribution to estimate wind speed frequencies each month. The power curve for each wind generator is given by the manufacturer. The wind power calculator multiplies the Rayleigh distribution for each month by the power curve to calculate the power output for each month. The area under the power output curve is the total energy output for that month in kilowatt-hours.