If you bring up monorails anywhere on the internet, you are often mocked as a fool. Yet ask a critic specifically WHY they don’t like monorails, and rarely do they have an adequate answer. Instead they will like a drone, recite the monorail episode from the Simpson’s written by Conan O’Brien in 1993. While the Simpson’s has made some positive social commentary there is no evidence Conan had signicant expertise in this area. Even Matt Groenig (a monorail fan) said the impact that episode had on monorails “was sad”.
Before we examine monorails we should consider their competition for urban transit.
- Walking:
- Slow
- Not protected from the weather.
- Biking:
- 4x faster than walking
- But very weather dependent
- Hills are a major problem
- Low cost
- Can get sweaty after a ride
- Some roads are dangerous to bike on.
- Buses:
- Very slow. A NY bus averages 11 mph (slower than a bike).
- Crowded.
- Limited capacity (at best a full bus may carry 60 people).
- Subject to traffic jams.
- Diesel buses are stinky and significantly contribute to smog
- Expensive to operate
- A new diesel bus will cost $500k+. A new electric bus can cost $800k+.
- Each driver will will need a salary/insurance/etc. Buses will need repair and new parts. Maintenance can cost $100-$200 per hour for each bus.
- They depreciate fast (figure 12 years). So a $500k bus will depreciate at 42k per year.
- Ride Share:
- Fast, but expensive
- Subject to traffic jams (and a contributor to them)
- Controlled by mostly two huge and very imperfect corporations
- Double parking in busy streets for picking and dropping off can be awkward
- Regular Car:
- If no congestion, very fast and flexible
- But parking and securing a car in dense neighborhoods can be very stressful and expensive
- Subject to traffic jams
- They do pollute
- Expensive to purchase and maintain
- Tram/Street Car:
- Slow and often subject to traffic jams
- More expensive than a bus, but has more capacity and does not need to refuel.
- Features a small “walk-shed”. This means you often don’t have to do a lot of walking to reach your tram.
- US regulations force trams to be ridiculously large and heavy to withstand a wide range of traffic accidents. This significantly raises cost.
- Metros/Rapid Transit:
- These are typically grade separated which increases speed and safety
- Some systems are noisy
- Tracks can require constant and expensive maintenance.
- Because rapid transit trains typically lack differentials, this results in excess wear on the wheels when banking a turn
- Expensive but can be automated and has a lot of capacity.
- Many underground stations are extremely expensive to construct and have horrid walksheds. Some metro stations in China actually can take more than 8 minutes of walking!
Now let’s look at monorails.
- They typically use rubber tires which reduce noise
- They can take sharper turns than rapid transit because they don’t have fixed axles. So no differential issues.
- They can take on steep grade because of their rubber tires (so can climb steeper hills than a metro).
- Typically grade separated (faster/safer).
- They can easily be automated to save significantly on costs.
- They have a narrow profile and can be built elevated in highway medians.
- Because they use concrete supports (instead of steel tracks) the “track” doesn’t get constantly warped and stretched (so almost no maintenance).
- They aren’t as fast as rapid transit metro trains and don’t have as much capacity, but not by much.
- The major downside is it can be difficult to switch tracks for a monorail.
- They are significantly cheaper to build and operate than rapids transit metros.
So let’s summarize. Owning a car in a big city is tough because of parking. Buses are not the answer because they are slow, stinky, and expensive. Grade separated metros solves the speed problem, but not the cost one. A monorail (ideally automated) is one the the cheapest way to realize grade separation because it’s support profile is no narrow. It is quiet and its track requires little to no maintenance.
For more information on monorails, I highly recommend checking out the Monorail Society website.