The 2006 Chevrolet Silverado looks like an ordinary pickup truck but appearances can be deceiving. Lorne Grieger lifts the hood to reveal a gizmo which makes a big difference.
It’s a special fuel injector which lets the truck run on biodiesel fuel and ethanol at the same time.
Biodiesel and hydrated ethanol (95 per cent ethanol and five per cent water content) are supplied to the engine from separate tanks. They are injected into the intake manifold at a single point. Both fuel systems operate simultaneously. Voila, dual fuel.
What’s the point? An engine blending regular fuel with ethanol at the point of ignition bypasses the refinery which blends gas and ethanol. The result: saving money by eliminating one step in producing ethanol-content fuel.
The implications are significant. It could mean fewer government subsidies needed to make ethanol-blended gasoline more price competitive with regular fuel. Not to mention cleaner-burning engines and lower greenhouse gas emissions, Grieger said.
The dual-fuel demonstration vehicle was on display last week at Manitoba Ag Days. Grieger, agricultural research and development manager with the Prairie Agricultural Machinery Institute at Portage la Prairie, gave a presentation on it.
The vehicle is one of only two of its kind in North America. The other is with the Saskatchewan Research Council, involved with PAMI, Ottawa and the Manitoba government in the project.
The ethanol injection rate is adjusted automatically, based on engine speed and load, Grieger explained. Ethanol is injected at a 75 per cent rate at idle, falling to zero per cent at full power. The reason for that is diesel has higher energy content, which is necessary at full engine speed.
Tests by PAMI show no overall reduction in engine power from the ethanol system or any major changes in fuel economy.
The vehicle can still operate on 100 per cent regular diesel if biofuels are unavailable.
Why use hydrated ethanol? That’s because five per cent water content is the maximum amount allowed before ethanol goes into its final (and expensive) refinement. Hydrated ethanol won’t work in a gasoline blend but it seems to work here, Grieger said.
It smells nice, too. Grieger said you can detect a sweet odour coming from the Silverado’s exhaust when the ethanol is at its maximum point in the mix.
PAMI is also experimenting with dual fuel in tractors. The result is similar, except the fuels are blended before they go into the engine, said Grieger. [email protected]