2010 Prius 92g/km and low emissions 89g/km version!

Well, Mag-X has revealed that the new Prius will manage 40 km per liter, but 38. It has also an interesting side view rendering

japanesegreencars.blogspot.com/2008/11/new-toyota-prius-ym2010-more-info-from.html

 

Could be, seems like Mag-X is about 6 months late with most of their other info though.

Rob

 

On the subject of direct injection - I doubt it would make as much difference in a Prius than it would in a normal car. In a standard petrol engine, you have to have a certain amount of fuel in the chamber in order for the spark to ignite it. That certain amount of fuel will produce a corresponding amount of power. However, if you don't need that much power (ie you're driving slowly) then you have to force the engine to slow down by restricting the air flow ie closing the throttle. This is inefficient, and it's one reason diesels are more efficient - airflow is never restricted in a diesel and speed is controlled only by varying the amount of fuel injected.

However in the Prius you don't have to slow the engine down to drive slowly. You can either shut it off altogether and drive in electric mode, or let it run faster and take the surplus energy and put it in the battery, rather than wasting it by throttling. There is a throttle valve on the engine though, you can see it when you take the air filter cover off, but I bet it spends a lot more of its time open than in a normal car.

It occurs to me that this could be the reason there's no diesel Prius. Diesel is efficient because of the greater expansion ratio (due to higher compresison ratio) and because direct injection allows for fewer losses. Well in the Prius the Atkinson cycle allows for efficiency closer to that of a diesel, and if my theory about reduced throttle losses is correct I bet a diesel Prius would only be slightly more efficient in terms of MPG than a petrol one. And given the higher cost of diesel and higher CO2 emissions, it'd probably be more expensive and less green.

Waffling post I know, but I'm bored at work on Christmas eve... what are you gonna do?

 

Can anybody explain how the 2010 Prius can achieve C02 emissions
"as low as 89g/km"?

89g/km = 143g/mile = 0.32lbs/mile = 16lbs per 50 miles.

The Prius avg fuel economy is about 50mpg = 1 gallon of gasoline

That is then 16lbs C02 produced per gallon of gasoline burned

The EPA and other sources present the gasoline combustion stochiometry as one gallon = 20 lbs C02.

Does Toyota have a process to reduce the C02 per gallon?

Thanks,

EVsRule!

EVsRoll.com

 

You are mixing up 50 MPG EPA (2008) standard with the emission rating from Europe.

89g/km is using UK test cycle where Prius get like 72.4 Imperial MPG = 60.3 US MPG.