ADVANCEDTHERMOELECTRICENERGY RECOVERYSYSTEMinLIGHTDUTYand HEAVYDUTYVEHICLES: ANALYSISonTECHNICALandMARKETINGCHALLENGES

Thermoelectric materials - materials thateploit a Keywords- TEmaterial, TEGenerator, Figure OfMeri4, newbulk phenomenon inwhichtheapplicaton ofheattocombination of Materials, two-dimensional quantum wells, LD,HD Vehicles. certain metals induces an electric current- areemerging as potentally important systems forincreasing fuelefficiency and Vehicular industry trends favorsolidstate(TE)Power decreasing emissions infuture automotive vehicles. conversion: Thomasseebeck a Germanphysicist, first noticed the Government regulations stemming fromenvironmental thermoelectic effect in1821whenhediscovered that avoltage was concerns andworldwide oilconsumption areforcing the developed inaloop containing twodissimilar metals, provded the automotive industry tomakeimprovements intailpipe twojunctions weremaintained atdifferent temperature. emissions andvehicle fuel economy. Incontrast consumers' Somedeices haveemerged overtheyears toexploit that property, expectations invehicle performance andcapabilities are buthaveingeneral beenhampered bylowefficiency ofabout 5% driving theenergyconsumption everincreasing levels. withcorresponding value of(ZT)equal toapprox one(andhigh Automotive original Equipment Manufacturers arenow cost) Despite thefact that thermoelectric devices arecompact, quite,planning toincorporate telematics, collision avoidance system, rugged, stable andvery reliable; thermo electrics have foundonly in vehicular stability control, additional powertrain/ body niche applications andtheir widewidespread acceptance dependscontrols, navigation, steer bywire, andsensors. Apartfrom upondiscovery ofnewmaterials with high conversion efficiency. abovesaidaccessories, newdevices likeABS Pump,Active suspension, heated front seat andengine valve control etcwill Theissue ofthermoelectric efficiency forautomotive application is incras theaeectrical andeninemodemmidrag car examined fromthestandpoint ofwhatmaterial figures ofmerit (FOMs) will enable solid-state devices tocompete with conventional average electrical loadisprojected around 3-5KW with peak electricity generator orvaporcompression refrigerators. Itis powerloads ofover7KW. estimated that FOMsof(ZT) equal toorgreater than8will be Unfortunately, today's vehicle cannot meettomorrow's needs. required Someoftheemerging newbulkmaterials mayeventually reach thatlevel ofperformance. Howeverlayered thin -filmTheinternal combustion engieefficlency Is,atmost40% structures based ontwo- dimensional quantum wells andshortefficient andmuchofthemechanical energy notonlyproved period super latices appear tohavequalities will enable rapidpowertothewheels, butalsosupports theperipheral systems attainment ofFOMsthatsignal economic competiveness. There suchas pumps,condensers, generators andperipheral arenumber ofbigcompanies inU.SAlooking into TE-basedelectronics. Inorder toincrease thevehicle efficiency and waste heatrecovery. Thegoal istousethat excess heat tocreatereduce energy constraints OEMsarelooking into alternatives electricity that wouldsupport manyoftheexisting vehicle systemlike 42-volt powersystem, fuel cells andhybridized vehicle andtodeliver thesufficient power tobeable toreplace mechan icalarchitecture. Itisevident that, Worldwidemanyvehicle system with electrical system~