I almost never see green bars...

My 2007 is usually around the blue-green boundary. Of course, as I live in Maine, I have needed the air conditioning only twice this year. Generally the car wants to keep the battery at that blue-green boundary, and when it gets into the brown should really be making efforts to charge it.

Have you done a 12v battery check? Low traction battery is often an indication of a failing 12v auxiliary battery.

 

More pulse and glide, gliding and consistent speed will go a long way toward getting and holding onto green bars.

 

We got ours in March, so we did see some snow, I wasn't the one driving it for the most part. My sweetie claims that it drives better than our old Subaru Legacy, (though the ground clearance is less, and that was a problem when the snow was deeper than that). We had no studded tires at that time, so I am going to see how it goes this winter before committing to them.

 

Grille blocking and engine block heaters help the engine warm up faster. There's a benefit for fuel economy but as with any car it operates better once it has warmed up properly. Plus grille blocking helps keep some crap out of the engine bay.

If your car is garaged an engine block heater will definitely help it warm up. Our Gen 3 is parked outside so an engine block heater wouldn't be as effective and I haven't bothered.

I just use grille blocking on my Gen 3. It's a bit quicker to warm up than a Gen 2 anyway so you should see more benefit. Grille blocking is very easy (generally, push pieces of foam pipe insulation between slats on the grille) so it can be for everyone. But, for obvious reasons, it can cause overheating in warmer temperatures so unless you have a device that allows you to monitor temperatures you'll probably want to take a safe approach. Other threads have good information.

As for tires, it would depend on where you live in Maine, what roads you drive on and how you drive. From what I've read a 2007 Prius should be fine with good snow tires, especially if you don't race like a left-lane SUV driver. There are posters here who drive their Gen 2's through Colorado winters.

I'm in Central Maine and I survived last winter in our Gen 3 on the regular tires just by driving sensibly. But, I live in a city, commute to another city, can take I95 in bad weather and generally just drive on main roads.

 

It's not necessary, but it can help. I never use grill blocking or heaters with our Michigan winters, but then I don't drive on a daily basis. For me it's just not worth the bother.

Tom

 

If you drive the Prius over 50 mph for over 40 minutes
your likely to see the battery SOC go green ( >= 67% state
of charge). If you drive in mainly stop-n-go city and
suburban driving you'll normally wont see the SOc level
go green.

You can force the prius to charge its HV battery.
With the Prius on but in park mode holding down the brake
pedal all the way down ( keep the emergency brakes on too)
then put the Prius into Drive while keeping your foot on the brakes,
and then using the other foot to press the accelerator
all the way down - while the Prius won't move, it will
engage the ICE to generate electricity - keep pressing
down the accelerator until your SOC indicator goes green.
I've done this on my 2010 Prius - it wastes gasoline but
it does artificially put your traction battery at a higher SOC.
This technique was used in the last Cleanmpg.com
Hypermile Fuel Efficiency Challenge to make sure that
every driver started off with the same SOC when he
started.

If you don't normally go on the highway and you
dont want to artificially raise the SOC BUT you'd
still would like to drive more efficiently so that once
in a while the SOC will go green - then you need to
learn hypermiling driving techniques - which
it sounds easy but it took me about 18 months
to really learn - hypermiling requires a focused
driver - and if there's alot of traffic on the road
its much harder to do...

BTW: Grill blocking helps in urban/suburban stop-and-go driving
when the temperature drops below 45 Fahrenheit because it
helps keep the engine coolant warm even when the gasoline
engine is turned off. When the car's engine is constantly
on and running hard like in a superhighway environment (+50mph)
for over an hour (e.g. 2 hours) then grill blocking does
not increase fuel efficiency that much.

 

I see green bars a lot in the winter, when the Prius runs the engine to make heat.

Tom

 

fyi - The latest weather report I've seen is forecasting that Hurricane Irene will hit dead center into Maine instead of Massachusett.

===

This is the most comprehensive article on winterizing a Prius
that I've found sofar.

A Hybrid Owner's winter Survival Guide
by Manuel Santos of Cleanmpg.com Nov 19 2009
( winterizing a 2nd gen 2007 Prius)
A Hybrid Owner’s winter survival guide - CleanMPG Forums

===

Here are detailed step by step instruction on
how to install an Engine Block Heater (EBH)
on a 2nd generation Prius if you are a DIY type.

http://priuschat.com/forums/gen-ii-...ine-block-heater-yourself-guide-may-help.html

===

Here are detailed step by step instructions on
how to jump start your 12 volt battery
on a 2nd generation Prius if you are handy.

How do you jump start a Prius? Can I do it by myself? - Yahoo! Answers

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This video by usbseawolf2000 demonstrates
how a coolant thermo bottle and grill blocking
helps a 2nd generation Toyota Prius improves
its overall energy efficiency in the cold

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