Fuel Economy and the EV button we didn't get.

I just posted this on Yahoo but I think this could start off a great discussion among the veteran Prius owners about how to best keep the approach the commute I've describe below. I get similar low mpg numbers when I have to drive home through a neighborhood that has about 16 speed bumps about 100 feet or less apart.

My commute home is usually at a snails like pace through terrain that
is is somewhat uphill. When the traffic is very very slow << 5 mph
I'm all stealth. Tonight I had 10 minute of 99.9 mpg. But that was
followed by 5 min of << 20 mpg. The car was fully warmed but this is
where I think the EV button would excel. I had plenty of battery
left but the line of cars would stop completely then accelerate
uphill to 20 mph....then slow and finally do it all over again. Try
keeping your car in stealth from a stop uphill. It's only possible
with the slowest starts and the most flat of hills. Otherwise you're
seeing 5-10 mpg. Pulse driving just doesn't cut it either because
the traffic isn't accelerating fast enough to allow that, but fast
enough to cause you to drop way way way behind if you try to nurse it
in stealth mode uphill from a stop.

If I had the EV button I'd see 50 mpg instead of 38-40 for my 11 mile
commute. I regularly see 60+ mpg for the commute to work because the
traffic moves in a much more smooth manner and it's now slightly down
hill and easier to keep it in stealth. It would be great if I could
accelerate at a moderate rate up a slight incline in stealth to say
20-25 mph, which is impossible now.

I think better economy is achieved when you can use the battery most
efficiency. And that is to avoid depending on the ICE when it's most
inefficient, like in the commute described above.

As a side note, I saw 70+ mpg on my commute last week one day when
the car was fully warmed up and I just did a fill up. But 42 is
about my best so far comming home, which works out to about 50 mpg
for 90% stop and go traffic. But I'll always be searching for ways
to get more, that's part of the fun of driving the Prius.

 

By heavy throttle do you mean say something greater than 1/2? In these situations I'm in, it would not take much more acceleration to keep up with the flow of traffic. But is is slightly uphill and trying to keep it in ev mode is near impossible as you know. So I end up kicking in the ICE and see 10-12 mpg until I've started to close the gap. Then I slow down so I don't have to hit the brakes overly hard. Many times the traffic once again stop abruptly, then I have to pay this penality all over again. If I elect to let the traffic go ahead and they don't stop the gap can become execessive and the drivers in the back get very ticked off (don't blame them). So I try to keep up as smoothly as I can. If I do a good job I see maybe 43 mpg on the commute home, if bad maybe 37 mpg. But I can always get low 60's to work, even with the warm up period.

I had to drive downtown the other day and that type of traffice is ideal. Nice and flat, lots of lights, the next one is always red, lol. I stayed in ev mode for most of the time there because I arrived with a fully charged battery.

So are you saying the ev mode cuts out much like it does now, or can you get some moderate acceleration before that happens? What does the 1 km represent in battery charge level. Does ev kick out once two bars are gone from full for instance? Thanks.