Range based model for technology requirements hybrid vehicle technology assessment case study

Abstract

This paper presents a performance based technology assessment model. The model was used in a case study aimed at improving the performance (mpg) of a basic hybrid vehicle. The assessment model and case study included a gap analysis, a scouting report for candidate technologies, a technology evaluation and selection model, implementation recommendations, and a diffusion and adoption analysis. Hybrid vehicles are a radical innovation in vehicle manufacturing that can potentially reduce the amount of carbon emissions associated with "mainstream" vehicles. At 50 mpg on the highway, the hybrid performance was equal to non-hybrid performances of lightweight diesel and gas-powered vehicles. The performance declined to approximately 35 mpg in the city when accessories like the air-conditioner or heater were used or the windows were left down and the engine cycled on and off due to frequent start-stop cycles. We focused on improving the performance of the vehicle during the first gallon of gas consumption by adding or swapping components such as batteries, battery chargers, fuel cells, and efficient engines, electrical motors and generators. The improved performance was accomplished by charging the batteries overnight and operating the vehicle in a purely electric-vehicle mode before the engine started. Doubling the mass of NiMH batteries extended the EV-mode range. These two changes together extended the performance range in the city and on the highway. Actual performance of any vehicle is driver and path dependent. (c) 2006 PICMET.