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This paper details the control system development process for the University of Washington (UW) EcoCAR 2 team over the three years of the competition. Particular emphasis is placed upon the control system development and validation process executed during Year 3 of the competition in an effort to meet Vehicle Technical Specifications (VTS) established and refined by the team. The EcoCAR 2 competition challenges 15 universities across North America to reduce the environmental impact of a 2013 Chevrolet Malibu without compromising consumer acceptability. The project takes place over a three year design cycle, where teams select a hybrid architecture and fuel choice before defining a set of VTS goals for the vehicle. These VTS are selected based on the desired static and dynamic performance targets to balance fuel consumption and emissions with consumer acceptability requirements.

Oil extracted from microalgae has the potential to offset demand for petroleum, if conditions of cost and scale can be met. In this paper, we present the compositional differences of fatty acid methyl esters (FAMEs) obtained by solvent extraction from two different oleaginous microalgae. Oil samples were extracted from a proprietary alga (Alga X) and a more common Nannochloropsis oculata (NC) using the Soxhlet process with n-hexane. The neutral lipids contained in Alga X comprised approximately 40 to 60% of the algal dry weight, and the oil was mostly converted to methyl esters using a transesterification process. On the other hand, NC produced approximately 25% lipids, but the yield of methyl esters was often less than 1% and subject to high variation. FAMEs were analyzed using gas chromatography and the average chain lengths for NC were shown to be greater than the average chain lengths for Alga X.

One barrier to the use of algae feedstocks as a source of CO2-neutral, renewable liquid fuel is the potential for high processing costs. An important processing step is the extraction of oil from the biomass. While there is substantial industrial experience in lipids from oil seeds, these processes may be unattractive for algal fuel oil due to high costs. Laboratory data suggest, however, that the relatively fragile nature of algal biomass may speed the mass transfer processes that control the extraction rate, and thus either reduce equipment size or allow increased throughput. In the present paper, laboratory-scale extraction data are used to develop a finite difference model of a full-scale extractor. The results indicate that such an extractor may have an increase in throughput of a factor of 5-10 without losing extraction efficiency.

Means to extend the range of cryogen (liquid nitrogen or liquid air) powered automobiles via burning a small amount of fossil fuel (gasoline or liquid methane) have been investigated. By utilizing both an ambient air-heat exchanger to vaporize the cryogen and a fossil fuel-fired superheater to elevate the temperature of the gaseous product, the range of the vehicle can be three times that of an ambient-heated propulsion system while not exceeding current ultra-low emission standards. Internal and external combustion power cycles using either liquid air or nitrogen as the working fluid were found to be more fuel efficient than an internal combustion engine operating on the standard Otto cycle. The fuel-cryogen operating expense for the proposed hybrid propulsion systems was found to be higher than that of the conventional automobile; however, the performance calculations were very conservative.