Imagining Elon Musk’s Million-Person Mars Colony – Chapter 14

Imagining Elon Musk’s Million-Person Mars Colony – The greatest thought experiment of all time

by Marshall Brain

Chapter 14

What Will the Transportation System on Mars Look Like for Mars Colonists?

How will the people in the Mars colony get around? How will people transport themselves from one place to another? It is an important question, because the new colony on Mars will want and need to optimize the transportation equation for the colony. By contrast, it seems like the United States has done the opposite of optimization – we have created the most expensive transportation system we could possibly create, and along with the cost we expect the citizens of the United States to put up with a host of other problems.

A nation like the United States spends a surprisingly large portion of its economy on transportation. If we for the moment ignore airplanes, ships, trains and trucks from our calculations, and just focus on the private automobile portion of the United States transportation system, think about all of the problems that we create for ourselves because of our dependence on private automobiles.

First, there are the automobiles themselves. “There were an estimated 263.6 million registered passenger vehicles in the United States in 2015” [ref]. This means that there is approximately one automobile for every adult in the United States. Every adult has to own an automobile simply to live their lives in the United States. There is a tiny set of cities in the U.S. where you could survive without owning a car. New York City is one example. Maybe San Francisco and Washington DC. But that is about it. Everywhere else, you own a car if you are an adult in America.

Transport Systems in USA – Discovery Documentary

These cars are incredibly expensive. The average annual cost to own and operate a vehicle in the United States is $8,698 per year (2015). “This research examines the cost of fuel, maintenance, tires, insurance, license and registration fees, taxes, depreciation and finance charges associated with driving a typical sedan 15,000 miles annually” [ref].

If we multiply the 263,600,000 cars in the U.S. by $8,698 per car, the citizens of the United States are spending $2.3 trillion per year to operate its fleet of motor vehicles. This is a huge amount of money – about 13% of GDP.

But it is even more serious if we consider the take home pay of the average American adult, and contrast it against the cost of owning an automobile. “The reported income of the bottom 90% of tax filers in the United States decreased from an average of $33,621 in 1970 to $30,980 in 2013 for an aggregate decline of $2,641 or a percent decline of 7.9% over this 43 year period.” [ref], [ref] So if the average take home pay is $31,000 (before taxes) and the average cost of operating an automobile is $8,698 per year, that means 28% of income is being spent on the vehicle that the adult must own to get around in America.

28% is an incredibly high number when we consider that the average car sits idle 90% or 95% of the time. A person buys a car, and might use it two hours out of each day. The rest of the time, the car is parked in the garage at home or the parking lot at work. If the car is idle 22 out of 24 hours, it is idle 92% of the time.

The cost of all those parking spaces is also incredibly expensive. A person needs a place to park the car at home, at work, while shopping, etc. These parking spaces add up, to the point where there are multiple parking spaces being built and maintained for each car in America. Look at this map to understand the problem:!1m18!1m12!1m3!1d4612.36470114997!2d-78.73998614861456!3d35.76151813307373!2m3!1f0!2f0!3f0!3m2!1i1024!2i768!4f13.1!3m3!1m2!1s0x89acf49be5540d15%3A0x49ae662fa8e7cba5!2sCrossroads+Plaza!5e1!3m2!1sen!2sus!4v1496871672664

This map shows a typical big box retail shopping center in the United States. The white areas are the roofs of the stores. The darker gray areas are the parking lots. The amount of space devoted to parking is actually larger than the area for the stores themselves. Parking is a tremendous waste of space. It also spreads the stores out and therefore makes walking between the stores more difficult.

Now consider this: there is all of this parking space waiting for you at millions of malls, shopping centers, stores and restaurants across America. Let’s not forget the gigantic parking lots at airports, sports arenas, fairgrounds, hotels, etc. There is also a parking space waiting for you at work – a dedicated parking space for you, since your car sits there idle all day. And there is also a parking space waiting for you at home. In other words, the parking space that society has created for cars is utterly gigantic.

Then there is the congestion and traffic jams we find in every major city. Most cities suffer with traffic congestion so great that it turns interstate highways into parking lots every day. What should be a quick commute turns into a 60-minute or even 90-minute frustration-filled struggle to get to and from work. This table shows ten major cities in the U.S., and the amount of economic pain that is caused by congestion:

Note that this list covers only the Top 10 cities, so it leaves out other well-know problem cities like Atlanta, Austin, Orlando, Las Vegas, Philadelphia, Denver, Miami, Dallas, etc. In the following map of 5PM traffic in Atlanta, every major highway has become a parking lot [Source: Google Maps]. This pattern is typical of any major city in the United States:

This level of congestion is a major problem for people living in these cities, because it means that the transit system has failed. If you cannot get where you want to go – if you get onto a highway and come to a dead stop in traffic – this is not transit.

So let’s summarize the problems that America’s private-car-on-paved-roads transportation model is causing for the citizens of the United States:

  • Just about every adult in the United States is forced to own an automobile in order to get around.
  • Therefore each adult is forced to pay an average of $8,700 per year to own and operate that car.
  • This $8,700 per year car sits idle 90 to 95% of the time.
  • This amount of money represents about a third of the average adult’s take home pay.
  • The United States has to spend a tremendous amount of money for redundant parking spaces for all of the cars.
  • If you try to use your car to get to work or to return home, chances are you are stuck in a huge traffic jam.

The part that is so amazing about all of the congestion (and the associated frustration) that we have created in our cities is the fact that every bit of it is man-made. We can complain about the weather, but we really have no control at all over the weather on Earth right now. Traffic, on the other hand, is completely man-made. We have designed the transit systems we use today and spent trillions of dollars building them. To spend all of that money on such a terrible outcome is a tragedy.

Where does all of this traffic and congestion come from?

Why does congestion like this occur in every major city? What is happening when cities become so congested that people can no longer drive at the posted speed on their highways? Congestion indicates that there is a capacity problem. There simply is not enough road capacity to handle the number of vehicles wanting to use the roads.

We know it is a capacity problem because these same roads have no problem carrying traffic at 10PM. It is quite easy to move around in Atlanta at 10PM because there is plenty of capacity compared to the number of vehicles at 10PM. But during the day, and especially at rush hour, the capacity is not anywhere near where it needs to be for the number of vehicles.

Stuck: The Problem With Los Angeles Public Transportation

Why is there not enough capacity at rush hour, and why does congestion seem to be a foregone conclusion in any major city in America? Congestion occurs because we use a private-automobiles-on-paved-roads model for most transit in the United States. Unfortunately, this model is so expensive that cities cannot afford sufficient capacity to meet the needs of the population. And they cannot afford it on two different fronts:

  1. Roads are extremely expensive to build (for example $10 million per mile for a new lane of Interstate highway) [ref]
  2. Roads take up a very large amount of land relative to the capacity that they provide, and land is in very short supply in a city

Think about the typical sedan owned by a typical American. We will use the Elon Musk’s Tesla Model S as an example, because this car is electric (therefore having a low or zero carbon footprint, and likely a popular choice in a carbon-free future) and will probably be the first completely autonomous vehicle to see widespread use (all cars in the future will be autonomous). The problem with the Tesla Model S, and most sedans, is that they are big and heavy. The Model S is 16.3 feet long and 6.4 feet wide [ref], so it takes up 105 square feet of road space. It weights nearly 5,000 pounds. Most commuters in America drive alone, so all of this space and weight is devoted to carrying a single person. The average automobile occupancy in the U.S. is just 1.6 people, and 1.1 when commuting [ref].

This very large, very heavy automobile containing one person then gets on an interstate highway or a city street with lanes that are 12 feet wide. Even if Model S sedans are packed bumper to bumper, they now take up twice as much square footage, or about 200 square feet per car. And once the car starts moving at a normal highway speed of 50 or 60 MPH, the space expands again because of the spacing between cars in the lane. Now a car consumes 600 square feet or more. What this means is that the amount of space taken up by roads becomes gigantic, and they are extremely expensive to build. A single lane of interstate highway can cost $10 million or more during the construction phase, and then there are maintenance costs as well.

The problem for every city using the private-automobiles-on-paved-roads paradigm is that there simply is not enough money, and more importantly not enough land, to build the capacity needed to hold all the 105-square-foot, 5,000 pound cars that want to use the roads. If Atlanta, for example, wanted to build enough capacity to really handle all of the rush hour traffic, it might need 40 or 50 lane highways running through the middle of town. Obviously this is an impossibility space-wise, and the cost of such a project would be gargantuan. And imagine trying to use a 50-lane-wide highway. If you want to drive in the left most lane, you would need to change lanes 50 times. A 50-lane road is completely impractical.

How Will the Mars Colony Solve the Transportation Problem?

To understand what a transit system for the Mars colony will look like, we can ask a set of simple questions:

  • Would any of us choose to live in a city where a 20-minute commute turns into a 60-minute or 90-minute frustration-filled, stop-and-go mess at rush hour? Of course not. No one wants to experience the expense and aggravation of the congestion seen in cities like LA, Washington DC, Atlanta, and Austin. Obviously we want adequate capacity in the Mars transit system.
  • Would we choose to live in a city where a private automobile is, by and large, the only viable transit option available to the vast majority of citizens? Of course not. The average annual cost of owning a private automobile is $8,700, and that car generally sits idle 90% of the time.
  • Would we choose to live in a city where so much space and expense is wasted on parking? Of course not. A typical city in America is spending gigantic amounts of money on parking spaces to hold all of these idle cars. There are parking spaces at home, at work, at every shopping venue, at airports, sports arenas, hotels, etc.
  • Would we choose to live in a city where there is not enough transit capacity to meet the future needs of a growing population? Of course not, because this is a recipe for paralyzing congestion which no one wants.

The Mars colony will address and eliminate all of these concerns by using a completely different transit solution on Mars. Specifically, the Mars transit system will look like this:

  • The Mars colony will have a central information system that knows exactly what is happening with every person and vehicle using the city’s transit infrastructure. The system will take in data from myriad sensors, smart phones and applications and use that information to create optimal travel modes and routes for all of its users.
  • The Mars colony will have sufficient transit capacity to handle the travel needs of all of its citizens throughout the day. The lack of that capacity is what causes congestion, so congestion will be eliminated.
  • The Mars colony will use autonomous vehicles. Every part of the transit system in the Mars colony will be automated. There will be no human drivers for cars, buses, trucks, etc. in the Mars colony
  • The Mars colony will not use the “private automobiles driving on roads and highways” paradigm, because this paradigm is too expensive for both citizens and the city. No one will need to own a car on Mars.
  • The Mars colony will instead deploy much less expensive modes of transit, such as small, electric, automated, vehicles.
  • The Mars colony will eliminate the long wait times typically seen in public transit systems on Earth today. Instead, an on-demand approach will mean no waiting.

An optimized system like this for Mars would use much smaller, lightweight vehicles.

Alternative #1 – Personal Rapid Transit

Personal Rapid Transit (PRT) systems use lightweight vehicles running on inexpensive overhead track, as demonstrated in this video on SkyTran:


In a PRT system, the track is elevated to keep it out of the way of pedestrians. It also makes the track incredibly less expensive than a road to build, and construction time is minimal. Best of all, the elevated track uses no land to speak of. When more capacity is needed, it is very easy to add more track because it is overhead rather than on the ground.

A number of different PRT architectures have been proposed [ref]. The SkyTran system shown above is one of many. However, the notable benefits of any PRT system include:

  • Vehicles are small and light (e.g. 500 pounds), sized to hold one or two people.
  • No waiting. Vehicles are waiting for you when you arrive at the station.
  • Passengers ride alone or with a friend. It is “personal” rapid transit.
  • No stops along the way. Stations are offline and you are riding alone so there are no stops for other passengers.
  • The track is lightweight, inexpensive and easy to erect.
  • The track is overhead, out of the way of pedestrians and taking little or no land.
  • When the vehicles need to park (e.g. at 3AM when few people are using the system), they can park either in stations or in highly compact depots in out-of-the-way places. The vehicles can park in the depots nose-to-tail and door-to-door so they take up a tiny amount of space compared to a typical sedan parking in America. Parking can also be stacked to reduce space even more.

By making good use of all of these advantages, A PRT system on Mars will be an order of magnitude less expensive than the personal-cars-on-paved-roads model seen in America today, it will waste only a tiny amount of out-of-the-way space on parking, and there will be zero congestion or waiting. Overall, it will be a huge win for the Mars colony in terms of efficiency, cost and convenience.

Alternative #2 – Passenger Drones

Passenger Drone technology is just getting off the ground in 2017, with no widespread deployments yet, but it is interesting to compare to PRT technology. These videos explain the possibilities, using the EHANG184 as an example:

Green Technology – World’s first passenger drone unveiled at CES 2016

The obvious advantage of passenger drones: there is no track required, and therefore no cost for track.

There are also disadvantages however:

  1. The vehicles are more expensive.
  2. The amount of energy required per trip is significantly higher than with a PRT vehicle. Flying is energy-intensive because of the cost of overcoming gravity.
  3. A PRT vehicle can get energy from the track. A passenger drone must carry all of its energy, meaning big batteries and long recharge times.
  4. The size of a safe landing area can be significant. Putting these landing areas on roofs is one way to mitigate the problem.
  5. If there is a need to move a large number of people (e.g. 1,000 or 5,000 people are leaving a theater), landing and taking off hundreds of drones gets complicated. With PRT it is easy to build a hundred-vehicle station next to the theater that can quickly load thousands of people and send them on their way.

It is easy to imagine the Mars colony using a mix of the two technologies, depending on the size of the colony.

Alternative #3 – Bicycles and Electric Bicycles

If you live in the United States, bicycles can seem like a fringe technology. Bicycles are rarely used in any significant way. Problems with weather, the longer distances seen in a typical American commute (due to low density), and the danger of mixing in with automobile traffic, make bicycles less appealing as a mode of transportation.

But in a country like the Netherlands, bicycles are everywhere:

From the Netherlands Translating the World’s Best Bikeway Designs

The advantages of bicycles are obvious:

  1. Bicycles are extremely light and small – less than 50 pounds.
  2. Bicycles are extremely inexpensive compared to a car. The 5,000 pound Tesla Model S mentioned above starts at $68,000. That is $13.60 per pound. You can buy a nice bicycle from a brand like Schwinn at Target or Walmart – it weighs 30 pounds and costs $300, or $10 per pound. The price per pound is roughly the same, but the bicycle is almost 200X lighter, making it far less expensive in terms of materials and human time to manufacture.
  3. Normal bicycles encourage exercise, while electric bicycles eliminate the exercise if you so desire.

The Mars colony is likely to be far denser than an American city like LA, there will not be any weather, and there will be no automobiles driven by accident-prone humans to run over and kill bicyclists, making bicycles a great option for the Mars colony.

>>> Go to Chapter 15

Mars Colony Table of Contents

  • Preface
  • Chapter 1 – Elon Musk Makes His Big Announcement about the Mars Colony
  • Chapter 2 – The Many Thought Experiments that Mars Inspires
  • Chapter 3 – Why Do We Need a New Socio-Economic-Political System on Mars?
  • Chapter 4 – Imagining a New and Much Better Socio-Economic-Political System for the Mars Colony
  • Chapter 5 – What Happens When We Add a Massive Amount of Farm Automation to the Mars Colony?
  • Chapter 6 – How Will the Mars Colony Produce its Clothing?
  • Chapter 7 – How Will Housing Work for the Mars Colony?
  • Chapter 8 – How Will the Mars Colonists Construct Their Housing?
  • Chapter 9 – How do we provide other services like water, sanitation, police force, fire department, health care, etc. for the Mars Colony?
  • Chapter 10 – What might a typical “work week” look like on Mars? Who gets a free ride on Mars? Who will do the undesirable jobs on Mars?
  • Chapter 11 – What do we do with lazy people on Mars? What do we do with the assholes?
  • Chapter 12 – How would insurance work on Mars? Yes, insurance…
  • Chapter 13 – How will we make chips on Mars? Pharmaceuticals? Medical devices? “Stuff”? Will Mars be an actual backup plan for humanity?
  • Chapter 14 – What Will the Transportation System on Mars Look Like for Mars Colonists?
  • Chapter 15 – What will the political system look like? How will it be organized?
  • Chapter 16 – Building Experimental Cities on Earth Today to Find the Optimal Configuration for the Mars Colony
  • Chapter 17 – How can we apply the Mars colony’s principles to the billions of refugees and impoverished people on planet Earth today?
  • Chapter 18 – How will entertainment work on Mars? What types of entertainment will be available for Mars colonists?
  • Chapter 19 – How will children work on Mars? Who gets to have children? What is the colony’s stance toward children?
  • Chapter 20 – Starting the process of building experimental Mars colonies on Earth – Mars Colony Simulation 1000A
  • Chapter 21 – Can the economic system proposed for the Mars colony significantly improve the Welfare situation in the United States?
  • Chapter 22 – How much land will the Mars colony need?
  • Chapter 23 – Thought Experiment: What If Everyone Makes the Same Wage?
  • Chapter 24 – How Will Innovation Work on Mars?
  • Chapter 25 – Will there be advertising on Mars?
  • Chapter 26 – What should be the ultimate goal of the Mars colony?
  • Appendix A – Restaurants
  • Interviews with Marshall Brain on the Mars Colony:
  • See also:

[Feedback and suggestions on any part of this book are greatly appreciated. Contact information is here.]

The Official Site for Marshall Brain