Scooters from Lime and Bird have been causing a stir as they move quickly into cities. There's been blowback, because riders travel recklessly, often on sidewalks, and they also leave scooters just lying on the sidewalk, blocking things, because as dockless scooters you can drop them anywhere. Riders are also getting hurt, these are not the safest things to ride.

So cities are striking back, trying to stop, regulate or collect money from these scooter operators.

We can understand why, but cities should be very cautious in how they do this. Because these scooters are absolutely amazing when it comes to three of the big transportation problems -- emissions, congestion and parking.

Scooters are amazingly efficient

Let's start with emissions. These electric scooters use from 16 to 20 watt-hours per mile. That's astoundingly good. That's mind-bogglingly good. To give you some numbers in comparison for other electric vehicles:

Where do these disturbingly poor numbers for the transit systems come? In most cases from American Public Transportation Association Fact Book -- a transit boosting group.

If the numbers surprise you it may be because you have run into numbers that worked from a poor assumption.

The efficiency of a transportation system is not based on how many empty seats it moves. It is based on how many full seats it moves.

This number is called the load factor. For the scooters, the load factor is extremely high. For a pure docked scooter it's 100%, but it's never really that high because all scooter and bike systems need some repositioning to match travel patterns.

Earlier, I examined the energy used by moving and charging dockless scooters with cars. None of the companies was willing to comment on this topic, so I have to make rough guesses, and suspect that the recharge moves use 1 to 2 times as much energy as the people riding the scooters does. That seems terrible, until you realize these scooters only use 18 watt-hours/mile, and even tripled, they are vastly better than things like the New York MTA subway which uses 175 wh/p-mile, or the average US light rail train which uses 370. Even at 50 wh/mile the scooter is more than 7 times better than the light rail.

(As a note of explanation, I have also put 3 liquid fuel modes on the chart. It's hard to compare gasoline and diesel with electric vehicles, because the electricity is different in every city. However, one rough way is to consider that 1kwh of electricity, in the USA, on average, produces 744g CO2, and a gallon of gasoline produces 8,887g CO2. 1 gallon diesel makes 10kg CO2. This makes a gallon of gas the same as 12kwh and a gallon of diesel the same as 13.5kwh. In reality, the gasoline and diesel have other emissions, as do the electricity, and the electricity varies from city to city.)

There are other matters to consider. The energy to produce the scooters is trivial compared to all the other vehicles. A typical train car has 500lbs of metal per passenger, a passenger car has more.

Scooters blocking the sidewalk

The first complaint to come forward is scooters blocking the sidewalk. People just leave them anywhere, haphazardly, sometimes blocking or even littering the sidewalk. I think scooter companies could take some steps to stop this, because I believe they all contain accelerometer sensors which can track the orientation of the scooter as well as when it is moved.

To do this, they can insist the scooter be stored in a certain orientation. They could insist the scooter be folded or be vertically leaning against something. Or if flat on the ground, they could insist they have their kickstand deployed and are upright.

But the simplest thing is to let other members of the public enforce good docking of the scooter. Allow any member of the public who sees a scooter improperly stored to photograph it and its serial number and file a report. This could be matched against the person who last rented the scooter, unless other sensors indicate the scooter was moved 30 or more seconds after the user clocked-out of their rental.

Riders with multiple complaints could get penalties. This would get people doing a better job parking them. It is possible some people might deliberately try to move scooters right after seeing them parked for the lulz, but I don't think that will be a giant problem and this would have geographic patterns.

Scooters driving on the sidewalk

Scooters also take less space on the road -- that is to say, when they are on the road. One of the factors causing cities to hate them is that people love to take them on the sidewalk. They don't feel safe on the road, of course, and even on the road they are resented, as bicycles are, because they go slowly and take up a lane if there isn't a bike lane dedicated to them. Cities should be encouraging bike/scooter lanes and even consider taking space from cars in places where demand is high.

It's a bit harder to have software tell if a scooter is on the sidewalk. It is probably possible to make neural network software that can look out cameras and tell if a scooter is on the sidewalk or the road, but today's scooters don't have any hardware like this and it also requires power. In a few years time, 5G networks may offer precise location information that could be used for both controlling where scooters drive and where they park.

On the other hand, we do have to be careful about limiting rental scooters much more than we limit privately owned scooters; if we make them too unequal, the rentals may not be able to compete.

Enforcement could also be done by the public, who would photograph scooters driving on sidewalks with GPS log and time included. Even if no serial number were visible, the company has a log of where each scooter was at the given time and who was riding it, and often that will point to a unique rider -- and of course there will be a photo. After multiple complaints the rider would get notified that too many complaints are coming in, and after too many strikes they would get fined.

It should be noted that it is desirable that scooters are able to ride on sidewalks some of the time -- for the start and end of their ride, and at low speeds for certain short distances when it's too dangerous to use the road.

Are scooters replacing car trips?

There is a reasonable argument that scooters are mostly replacing walking, transit and taxi trips rather than private car trips. They tend to be used for trips of just a few miles or less, and in areas where parking is problematic enough to already discourage short car travel. Trips under a mile may involve replacing walking. Scooters are a big win over Uber/Taxi trips because they don't have the high minimum fare and often will go much faster through congested areas. When they do replace car trips, they are replacing not just the wasted energy, but congestion and demand for parking.

One valuable scooter use for car users is to avoid having to move a car. When a driver has a 2 (or more) stop trip in a downtown area, they can elect to move their car between the stops (at a high parking price) or try to walk/transit/Uber round trip between the stops. This is often impractical and the scooter can save a lot of hassle and parking money.

When scooters take people off transit, it can be argued they are not so wonderfully efficient, because filling an empty seat on transit is still usually very efficient even if the overall transit line is not efficient. Transit tends to do poorly at short trips, where factors like travel to stops, waiting at stops and doing transfers dwarf the actual travel time. The "near door to door" nature of dockless scooters is a big win.

Indeed, there is evidence scooters are also enabling longer haul transit by providing quick and cheap transport to stations from people who are too far away from them. Of course, privately owned scooters have done this for some time.

Scooters have other problems of course -- they are not good in bad weather, and they are not good for those with mobility problems. And riding them is not nearly as safe as riding in vehicles.

Time to experiment

Overall, the net energy win of the scooters, for all their problems, seems too large to overlook. While problems are arising and will arise, it seems that cities should try to embrace the scooters and fix the problems rather than clamp down on them. Cities should be challenging the companies to come up with good solutions to problems, and looking to new generations of scooters to provide real answers to future mobility questions.