[Mac]

I thought all Prius was SULEV till I see this site.
http://www.fueleconomy.gov/feg/findacar.htm

If I choose 2003 Prius on this site, it seems there are two types: SULEV type and ULEV type.

According to this site, SULEV Prius is sold at only several states in US, all other states sells ULEV Prius.

I wonder why Toyota doesn't sell SULEV Prius at all states. :?

 

[john1701a]

> According to this site, SULEV Prius is sold at only several states in US, all other states sells ULEV Prius.

The difference is actually that only those particular states recognize the SULEV rating category. Since their scale only goes as clean as ULEV, that's all that can officially be listed.

Prius sold throughout the country are all the same. They all have a SULEV rating technically, but actually achieving that for the entire 120,000 measurement duration is a complex issue without the availability of low-sulfur gas everywhere... yet. In just 2 years, that changes though.

 

[Mac]

Thank you for your info, John!

Now, it makes sense that this site shows different ratings on the same car.
I guess I needed more research to find out there are no SULEV rating at the most states.

I wish the SULEV rating becomes official soon everywhere so that many people can tell easily how clean Prius is! Currently, with the ULEV rating which is the same rating as Honda Accord and Civic, some people may not get convinced that they need a Hybrid car to make a real difference!

 

[jdbower]

The definitions may also need tweaking...

How can the Sequoia with a 14/18mpg city/highway mileage rating be ULEV? Yes, the pollutants per volume of fuel have gone way down but the amount of fuel consumed is still huge. These definitions should probably have mileage limitations, but then that paves the way for "fake" mileage ratings like the Insight which just push some of the pollutants to the US's dirty power production facilities (remember, the electricity coming out of the outlet is clean but we still need to generate it somehow!).

 

[RSnyder]

Um, the Insight is also an electric/gasoline hybrid. So it also does not make use of the power grid. Anyway, on the west coast, power from the grid does not come from coal, rather from hydro and natural gas, so grid powered electrics there are cleaner than hybrids. On the coal fired east coast, hybrids are cleaner overall than electrics (but only by a little).

As for ULEV Sequoias, in their category, they're cleaner than others, but of course smaller cars are cleaner overall. But if someone is intent on buying a giant SUV, wouldn't you rather they get ULEV instead of LEV in that category?

 

[jdbower]

But you have to plug in the Insight

Unless I've been mislead for the past few years, the Insight cannot keep it's batteries charged using just the engine. Hydro plants may be fairly clean, but don't kid yourself into thinking that they're environmentally correct - dams do awful things to the local ecology! Only hydro plants based on natural waterfalls are really useful from an environmental standpoint. If only people would dump more money into useful fusion power...

As for the Sequoia, I'd rather not have people buying an SUV simply because of the EPA rating misleads them into thinking it's better than another. Is the Sequoia really cleaner than a more efficient SUV with a much better fuel economy?

 

[jdbower]

I guess I have been mislead

At least the new Insight is self-sufficient. Was I thinking of the original model or just smoking something?

 

[johnson487682]

You were smokin' something.

No model of Honda Insight has included a power cord. However, you are correct to say its engine can't always keep the batteries charged. Honda's hybrid design (Insight and Civic) differs from Toyota's in many fundamental ways.

One key difference is that the Prius has _two_ motor generators, allowing the engine to recharge the battery with MG1 at the same time it is using MG2 to help drive the vehicle. This means the batteries don't get drained, even when driving uphill for long durations. Few Prius drivers have ever seen the "turtle", and most occurrences have been caused by cold weather conditions.

The Honda design has only a single motor generator, which means it cannot recharge its batteries while it is providing electrical boost. So, continual acceleration conditions can drain the battery, leaving the car to finish climbing the hill with only its gas engine.

Honda drivers who have switched to the Prius initially complain about the battery icon on the multi-display, because it only has 4 bars and doesn't show much detail. (The Honda displays have 10 bars on the battery icon--the same as on their gas gauge.) However, they quickly realize it is not necessary to watch the Prius battery icon, because it never goes down, it just alternates between 3/4 and 1/2. When driving a Honda hybrid, you have to watch this gauge constantly, so that you know when to slow down and drive less aggressively to prevent loss of electrical assist.

Douglas (2002 Silver, Wisconsin)

 

[RSnyder]

I am not an Insight driver (IANAID?), but the following is my understanding from old discussions on the Insight group (haven't been there in quite a while).

The Insight is quite capable of keeping its batteries reasonably charged under normal circumstances. Let me qualify that a bit: the CVT Insight can do so on its own, the manual Insight needs the help of the driver. As Douglas mentions, the Insight gives the driver much better information about battery management. The driver of the manual Insight needs to use this information in addition to other driving conditions in order to select the correct gear. Honda didn't provide much driver training, however, so battery draining became a hot topic on the group as they came to a concensus on proper driving technique. The arrival of the CVT Insight allowed the onboard computers to handle charge maintenance for those drivers that didn't want to be quite so involved in hybrid minutia (and were willing to accept slightly less performace potential).

The Prius only has a CVT, and the engine throttle is under the control of the computers, not the driver, so the driver has almost no influence on charge management. But even in the Prius, it's possible to drain the hybrid battery as I proved on the climb up Mt. Washington in New Hampshire. This version of the Prius does not light the turtle under these conditions, only under conditions of extreme (hot or cold) battery temperature. The old model (only sold in Japan) lit the turtle under any low battery condition, and that was the model tested by the magazines during the period leading up to the introduction of the Prius to the U.S.