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How Public Transportation Works

Electric trains powered by overhead power lines. Image obtained from Vagabond Shutterbug on Flickr: http://www.flickr.com/photos/waikikiweekly/.

This page pertains to the different modes of transportation in use worldwide today. Just like the other pages on this website.  I would recommend bookmarking it or subscribing by using the Feedburner form to the left.

Table of Contents

  1. Analysis of Public Transportation vs Driving Yourself.
  2. Cost of Public Transportation vs Personal Car Ownership.
  3. Know Your Monthly Fuel Costs.
  4. How to Calculate the Cost of Fuel Per Mile.
  5. Determining the Length of Your Commutes.
  6. Benefits of Owning a Personal Car.
  7. Transportation Mode Efficiency Per Person.

The Reason Behind Public Transportation

The reason for public transportation is relatively high efficiency. How could riding a big, 41,000 pound bus be more efficient than driving a 3,000 pound car?

The Answer

1 kg = 2.2046 pounds.

1 pound = 0.453 kg. Multiply the pounds by this to convert to kg.

An example Volvo 9700 bus which weighs 41,800 pounds carries up to 53 passengers. If each of these passengers weighs 150 pounds, that is a combined 7,950 pounds, plus the bus’ weight of 41,800 pounds, which results in a total of 49,750 pounds, or 938 pounds per passenger.

If all of the passengers were to drive their own sedans instead of buses, the weight of the cars would amount to 159,000 pounds, assuming that each of the cars weighs 3,000 pounds. Factoring in the weight of the 150-pound passengers, that totals 166,950 pounds.

That is a whopping 3,150 pounds of weight that has to be transported per person, compared to the bus’ 938 pounds, or 3.3 times more weight than the bus. So the bus doesn’t look so heavy and inefficient now, does it?

166,950 pounds of sedans requires more fuel than a 49,750-pound bus.

Analysis of Public Transportation vs Driving Yourself

Before I start calculating the costs of public transportation and personal car ownership, I will briefly tell you what costs are incurred and are not incurred by each mode of transportation.

Owning a personal car entails paying for:

  • Insurance premiums.
  • Fuel.
  • Maintenance.

Other Benefits of Public Transportation

  • No hassle of dealing with malfunctions and sitting at repair shops.
  • No expensive repairs.
  • No insurance premiums to pay.
  • You don’t have to drive because someone else is driving you.
  • You can rest briefly since you don’t have to drive yourself (be careful not to pass your stop).
  • You don’t have a car to wash.
  • If using high speed rail, you can get to your destination far faster than you would on a train if you are travelling a long distance. I said long distance because there is a delay before trains take off.
  • It is more comfortable than average cars.

Cost of Public Transportation vs Personal Car Ownership

On the fuel efficiency page, you will be taught how to not only determine your vehicle’s fuel economy, but also how to translate that into the cost of transportation in a personal car per mile. In this section, I will tell you how to use your car’s fuel economy rating to calculate how much it costs to drive a certain distance.

How to Determine How Much Fuel Costs You Monthly

This section is most relevant to people who are considering the purchase of a vehicle and want to know how much it will cost. Patiently follow the steps below. It is simple.

How to Calculate the Cost of Fuel Per Mile

Divide 1 by the “Combined” MPG rating of your vehicle (if you consider your driving habits to be average) and the result will be your vehicle’s fuel consumption in gallons per mile (GPM). Do not round off/approximate the results. Multiply the cost of fuel per gallon by the gallons per mile figure you got. The result is the cost of fuel per mile you drive.

If you rarely drive on highways, then use the highway fuel economy figure instead.

Example: Your vehicle has a combined MPG rating of 22 MPG. 1 / 22 = 0.04545454545 GPM. 0.04545454545 GPM x $4 per gallon = A fuel cost of $0.1818181818 per mile.

The Next Step – Determining the Length of your Commutes

You can do this by writing down your current odometer reading on a business day, after you drive to work, back home, and whatever other errands you ran for the day, write down the new odometer reading which will be higher if the odometer works.  Subtract the first odometer reading from the new one and the result is how many miles or kilometers you traveled.

Do the same for Saturday and Sunday.

Finally, multiply the miles traveled result that you got by 5 days. This is miles traveled per work week. Add Saturday and Sunday’s results to this and multiply the result by 4 since there are four weeks in a month. The result is average miles traveled per month.

Example: You travel a total of 20 miles per business day. 20 miles * 5 business days = 100 miles per work week which is 400 miles on business days per month. If you travel 40 miles on Saturday and 10 on Sunday, then 40 on Saturday + 10 on Sunday = 50 miles per weekend. 50 miles per weekend x 4 weeks = 200 miles. Add the 200 to the 400 miles per work week figure calculated above and your total distance traveled is 600 miles per month.

Calculating How Much Your Fuel Costs Monthly

Multiply the average miles traveled per month I showed you how to calculate above by the cost of fuel per mile which I also showed you how to calculate above. You’re done!

Example: 600 miles/month * a $0.1818181818 fuel cost per mile = An average fuel cost of $109 per month.


Benefits of Owning a Personal Car

  • If you can afford to, you can buy a nice luxury or sports car.
  • Being seen with their own vehicle is considered a pride-related benefit by some people.
  • You may be able to get to your destination faster, compared to a bus.
  • Potentially safer. This is safest for people traveling with expensive equipment such as laptop computers.

Insurance Cost of Personal Cars:

This section is coming soon.

Cost of Public Transportation:

Coming soon.

Transportation Mode Efficiency Per Person

The following data was obtained from the link at the bottom of this section which is titled “source”. I will try to provide you with as much detail as I can without causing confusion.

A rule of thumb is that larger passenger vehicles that carry more people per trip consume less fuel per person per mile. They only save fuel if they are actually occupied by many people. If you were the only one on a bus then that is a huge waste of fuel because it is mostly the weight of the bus that fuel is being burnt to move.

The fuel consumption of a vehicle per person, per mile is the additional fuel that the vehicle consumes specifically due to the person’s weight. The person’s weight makes the vehicle heavier (150 pounds heavier, as an average example), and the vehicle needs additional fuel to transport the extra 150 pounds of each person’s weight.

Personal Car: A car consumes an average of 3,538 BTUh (1,036 Wh) per passenger, per mile with 1.55 passengers. The car’s total energy consumption (not just the additional fuel burnt because of the passenger’s weight

Personal Truck: A truck consumes 3,663 BTU (1,073 Wh) per person, per mile assuming it contains 1.84 passengers.

Bus:

A bus consumes 4,242 BTU of energy per passenger, per mile with 9.2 people on it. This is either an unusually small bus,, or if it is a large one, this is nowhere near it’s capacity. If it is large, then this number was calculated with the assumption that the bus is operated in an area in which people do not normally use buses. A rule of thumb is that larger passenger vehicles that carry more people per trip consume less fuel per person per mile. They only save fuel if they are actually occupied by many people.

If you were the only one on a bus then that is a huge waste of fuel because it is mostly the weight of the bus that fuel is being burnt to move. The fuel efficiency in such a case would be ~10 mpg per person, which is similar to that of a 30-year-old car.

Source: ORNL.

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