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The cyclic and steady-state vehicle emissions, fuel economy, performance, and cold start behavior of an automobile equipped with a direct injection methanol engine are compared with those of three other comparable vehicles. One of the comparable vehicles was powered by a gasoline-fueled engine, and the other two were Diesels. One of the Diesel-powered vehicles was naturally aspirated and the other was turbocharged. All evaluations were made using the same road load horsepower and equivalent test weight. All the evaluations were conducted at low mileage. The emissions of the methanol vehicle are compared to California low emission vehicle standards, and to the emissions of another methanol vehicle.

The Schatz Heat Battery stores excess heat energy from the engine cooling system during vehicle operation. This excess energy may be returned to the coolant upon the ensuing cold start, shortening the engine warm-up period and decreasing cold start related emissions of unburned fuel and carbon monoxide (CO). A Heat Battery was evaluated on a test vehicle to determine its effect on unburned fuel emissions, CO emissions, and fuel economy over the cold start portion (Bag 1) of the Federal Test Procedure (FTP) at 24°C and -7°C ambient conditions. The Heat Battery was mounted in a vehicle fueled alternately with indolene clear (unleaded gasoline) and M85 high methanol blend fuels. Several Heat Battery/coolant flow configurations were evaluated to determine which would result in lowest cold start emissions.

EPA published the first results from evaluations of electrically heated catalyst (EHC) technology for light-duty automotive applications. Since then, a number of automakers, suppliers, and government agencies have published results from their heated catalyst development and evaluation programs. EPA has evaluated a number of start catalyst systems incorporating an EHC start catalyst followed by a larger, conventional main catalyst. These systems have proven very effective at reducing cold start related emissions from methanol vehicles at low mileage. This paper compares the results from several EHC + main catalyst evaluations conducted by EPA.

Studies of emissions from vehicles equipped with catalysts have shown that some unregulated emissions can increase when a catalyst is used. One example of this is sulfuric acid, which has been studied extensively. Other unregulated emissions include ammonia and hydrogen cyanide. In a number of studies, these unregulated pollutant emissions have been measured from light-duty vehicles and heavy-duty engines. These emission levels were used in air quality dispersion models to predict the resultant air quality levels. The ambient concentrations predicted for each pollutant were then compared to suggested concentrations at which adverse health effects may be found to determine if additional monitoring or control would be indicated for these pollutants. It was determined that mobile source emissions of sulfuric acid, hydrogen cyanide, and ammonia do not in general result in ambient levels of concern for the air quality situations studied.