Electrical System Design

1. Thermoelectric Stove for HaitiElectrical Engineers: Lauren Cummings, Colin McCune, Andrew Phillips, Xiaolong Zhang Mechanical Engineers: Marissa Blockus, Sam Huynh, Bri Stephenson-Vallot, Dustin TylerIndustrial Engineer: Brandon Harbridge Kate Gleason College of Engineering | Rochester Institute of Technology Customer Needs | Our Goals We set out to create a stove system that: Reduces fuel use by half; Reduce emissions; Increases efficiency and thus reduces costs for cooking; Allows locals to easily manufacture and sell the stove Is intuitive, transportable, and enhances conventional cooking techniques for traditional foods; Provides an electrical power source; and Improves the air quality for women and children • Motivation • Over 3 billion people use plant material or animal waste (biomass) as fuel for cooking which requires a considerable amount of their income, energy, and time collecting and preparing the fuel • Using biomass leads to deforestation, which is a big problem in Haiti • Most people in the Haiti live on $2 a day • 1.6 million people die each year from indoor air pollution • The 2010 earthquake has left people in Haiti without vital resources With one side cooled and the other side heated, the TEG generates electricity, and provides to a USB charger, which powers electronics such as cell phones Heat from the stove is absorbed into one side of the TEG while cool air from a fan helps to reject heat from the TEG on the other side. System Integration – Thermoelectric Generator (TEG) Electrical System Design Mechanical System Design The mechanical design features: 1. A stove intended to reduce emissions and increase efficiency 2. An air duct and a beam that directs both cool air from a fan and heat from the stove to the TEG unit The electrical system uses an Maximum Power Point Tracking (MPPT) technique to obtain the largest amount of power from the TEG unit. Both the battery and the MPPT provide power to the fan in the mechanical system as well as the USB charging system. Mechanical System Electrical System Results • We have reduced the time to boil, from the time the pot is place • on the fire, to 19 minutes. • Reduced fuel burn during the start up by 23% • Reduced fuel burn during the cook portion by 20% • Decreased carbon monoxide by 22% • Reduced particulate matter by 46% Controlled Cook Test – A realistic test, emulating results that would be achieved in the field. Temperature Difference and Power Production – Determined based on circuit voltage of TEG hooked up to an external resistance equal to electrical resistance of TEG Tests of the whole system with varying temperature from 100 C to 200 C are shown above. As expected, TEG and battery current goes down when the temperature drops. Negative battery means battery is discharging. It results in decline power of TEG. Both fan and USB currents and voltages are constant as designed, that results in constant power outputs. Special Thanks: Dr. Robert Stevens, Professor Ed Hanzlik, Dr. JagdishTandon, Mr. Neal Eckhaus, Dr. Lynn Fuller, Mr. Rob Kraynik, Mr. Dave Hathaway, Satchit Mahajan, and H.O.P.E. for Haiti