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Save Gas In Hot and Cold Weather

September 30, 2007 by Simon

This is an article I just wrote. It is going to be part of the fuel saving lessons you can via email at the Gas Mileage Calculator page. It’s about some of the ways you can save gas when it’s really hot or when it’s freezing temperatures.

Save Gas When It’s HOT or COLD
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Did you know that when it’s really hot in summer and when
it’s really cold in winter (snow and ice like) you can
save extra gas by preventing the effects of weather from
ruining your fuel economy?

Really Hot Weather, And How to Save

The number #1 gas thief in summer is the air condition. It’s
a heavy equipment that uses a lot of power and that power
comes from the engine using up more fuel.

Too bad it’s not as easy as just turning the AC off. Ok,
it is that easy, just turn the AC off and you will save
a bunch if gas. That’s easy.

The problem is what you do after you turn the A/C off,
maybe not all your passengers can stand the heat and
soon windows are open or even worse the A/C is back on.

The problems with the windows is that driving above 30mph
with open windows causes a lot of drag. It’s like cutting
a couple of large holes in the body of your car destroying
the fine aerodynamics built into it.

This means if you go faster than 30mph it’s better to use
the AC than to have you windows open. If you are going
at or below 30mph you will save fuel by have the windows
open instead of using the A/C.

If it’s really hot you might want to use the A/C even
if it costs you a couple of bucks. I won’t blame you.

You can still save by setting the indoor temperature a bit
higher letting the AC run at low power instead of full.

It’s also a good way to prevent getting a summer cold to not
set the indoor temperature too low when you are dressed
for the outdoor summer temperatures anyway.

Now to a completely different aspect of hot weather, make sure
you have a fuel cap and that it’s not broken!

This is essential as the car will get extremely hot when left
in the sun on an asphalt parking lot. This means the fuel also
gets hot and if there is no cap or a broken cap a lot of fuel
will evaporate, it turns into gas and leaks out into the air.
You still pay. And it’s bad for the environment.

Another thin you can do to prevent loosing fuel is to fill up
early in the morning or late in the evening.

There is two reasons for this. One is the same as above, fuel
will evaporate easier when it’s hot and you have the cap of
when filling up. The other reason is that the fuel will be
colder on the morning, making it more dense. You pay per
gallon or liter and if the fuel is more dense you will get
a little bit more fuel for every liter you pump.

Easy, fill up before the sun goes up. Or at least before it
gets too hot, the sun goes up at 4am here in summer and I’m
not awake at that time. If I’m not still at the computer
since last night that is, but in that case I don’t go
to fill up anyway.

Now to Cold Weather, Freezing Weather

The colder it is the more you can save. Not because of
some strange reverse logic but because normally your fuel
economy suffers from the cold weather and you can get
it back to normal, at least almost, with some simple
measures.

Step one: Get a block heater.

That’s important both for your fuel economy and for the
health of your engine. (If temperatures never go below
30F/0C in your area you don’t need to worry about a block
heater, you will benefit already at 50F/10C but it will
probably cost more than you gain.

The block heater uses electricity from the mains to
heat the engine before you go off to work, 1 hour is
usually enough but it depends on the outside temperature.

A cold engine will not be able to burn fuel efficiently,
there is usually a lot of smoke and it feels like you
had only a third of your normal horsepower (which is true)

The cold engine also doesn’t get lubricated well enough,
it will old quicker and in places where you have several
months of freezing weather, not using a block heater will
halve the life of the engine. If you drive short trips
it might not even go a 100 thousand miles before it’s
finished.

That was to say you have a double benefit, even a triple
benefit of the block heater. You save gas, you save your
engine and as the engine is now hot it will heat the
passenger area quicker, it’s no fun driving when it’s
freezing temperatures inside the car 🙂

Another thing, if you use winter/snow tires, in most
cases they will hurt your fuel economy as they are
made for grip, not to roll easily.

Make sure you switch to summer tires as soon as it’s
possible in spring. The summer tires roll easier
and you save gas.

WHERE TO GET AN ENGINE HEATER

If you are one of our US readers and need an engine
heater for just a few days in winter I’ve found
a cheap solution at Amazon.

It’s a magnetic heater that you can easily attach
to the oil pan under the engine whenever you need
extra heat in cold weather.

Kats 200W Magnetic Heater from Amazon

Use that link to see the heater. It can also be used
to heat water tanks, tractor engines or other things
made of steel.

Dedicated to improving your fuel economy,

Simon Byholm
MilesGallon.com

Where I live in Finland almost every car has a block heater installed. If you don’t have a block heater in the coldest weeks in February your car might not start. And even if it does start it will be smoking, without power and a real pain to drive until it warms up.

If you have story to tell about how you save gas in hot and cold weather just leave a comment here below this post.

Fuel Economy of Tonneau Covers Questioned

September 18, 2007 by Simon

You may have heard that you can improve the mpg of your truck by covering the truck bed with a tonneau cover.

I just read that SEMA has done some research on the effect of truck bed covers on the aerodynamics and it seems they found out that covering the bed on your truck will reduce drag by 4.2%–7.8%, effectively reducing the amount of fuel you have to use to overcome air resistance.

I read a post about this research over at Thundra Headquarters where the admin thinks the fuel savings are too small to warrant the considerable cost of buying a new tonno. Instinctively I don’t agree as there is other uses for a bed cover than just to save fuel

I was also qurious if the calculations are true, so I did some of my own. The main thing to consider here is that the tonno only improves the aerodynamics to a noticeable degree when you drive at highway speed. And not all of the fuel is used to push air, some is also used to overcome rolling resistance.

I will calculate with a 3% fuel saving on a 20mpg truck, doing a 20mile highway commute every day making it a total of 50miles per day with off work driving. I will also use a 6 day week to account for other than commute driving.

20mpg is 0.05 gallons per mile. 3% of this is 0.0015 gallons saved for every mile you drive. The total miles in a year is 50 miles x 6 days x 50 weeks in a year. This makes for 15000 miles a year with 0.0015 gallons of gas saved for every mile, thus 22.5 gallons saved.

With a gas price of $3 per gallon this would make a total saving of $67.5 per year with the tonno cover comared to driving without one, not bad.

Lets say you own you tonneau for 5 years, you will save $337.5 over this period.

What can I say, you won’t be able to pay for more than the most basic truck bed cover with the gas saved, but then again don’t you wan’t to have a cover?

There’s so many other reasons to get a tonneau cover for your truck than just to save gas. It will keep your stuff dry when driving in the rain, it will keep your stuff clean when driving in the dust. It will keep you light stuff from flying away when you drive on the highway.

It will also prevent you stuff from walking away when you stop in the city and if you get one that you can lock it will also prevent you stuff from walking away at night, when parked in the open.

With all these reasons to get a cover, isn’t it great that the gas savings of the tonno itself will pay for most of it?

Just remember that you get the most savings if you drive highway miles, if you are only driving around town doing street speed you won’t save much.

If when reading this you feel like you got a good reason to go get a new tonneau cover for your pickup truck, I have listed some reasonably priced tonnos from a US dealer here:

How to Save Gas With A Tonneau Truckbed Cover  

And always remember, if you need to check your gas mileage the mpg calculator is over at the main page.

Sparks of wisdom from our gas saving bag of tricks

September 5, 2007 by Simon

It’s not complicated to save gas, you don’t need any fancy vortex converters or gas saving devices. Neither do you need magnetic energy boosters for your fuel line. Most of these are the modern version of snake oil.

With this being the first post in the blog I’m going to give you a top three gas saving checklist.

1. Check that you have proper air pressure in your tires

2. Remove roof racks, bicycle racks, fancy extra lights if you don’t really need them, unused antennas. They all makes the aerodynamics of your car bad and increases fuel consumption.

3. Drive less if you can. Walk or use the bike on short local trips. Do more on one trip to town and cancel the other.

All these can significantly reduce your gas costs and are easy to do.

Remember we have the gas mileage calculator on the main page where you can check your mpg while working on improving it.

Simon