How Many Cars Do We Need for Carsharing to Eliminate Traffic Jams?

Traffic jams cause 80 percent of additional pollution and three to four times longer travel times in cities. With too many cars carrying just a driver and several empty seats, streets come to a standstill daily. If more drivers shared their cars we could easily alleviate these problems.

Most of us use our cars inefficiently, using just one seat for the driver and leaving more than four others empty. It is estimated that for every five cars that drive through Madrid, four carry just a single driver, while the fifth car only carries two people.

With this usage pattern, we use many more cars than are necessary, squandering fuel and polluting the air we breathe.

Everything gets complicated by the daily evolution of traffic.

Everyone is subject to different schedules and the demand for seats fluctuates greatly throughout the day. As indicated by the graph below, the supply of both vehicles and public transit is consistent over the course of the day (blue line of the graph). However, most transportation options are unable to handle peak demand during rush hour when available transport doesn’t seem to be sufficient.

Urban Traffic

To get a fuller picture of the problem, consider the following: If there are one million cars on the road in Madrid every day, we are wasting four million valuable empty seats. This is more empty seats than there are people traveling by metro and bus. Additionally, most of these seats are vacant at peak times, when we suffer most from transportation problems.

Could we take advantage of our empty seats to have fewer problems and live better?

Let’s study in detail why traffic jams occur, and their pernicious effects. In the following graph, the black line represents how the number of vehicles on the road over time (the actual traffic) evolves. On the left side we have growing but moving traffic, which is able to satisfy the demand. Problems begin when the maximum capacity of the road is reached. This usually happens on Madrid’s M-30 at about 7:00am.

When the number of vehicles on the road exceeds its maximum capacity, the road becomes congested. Cars start braking and, suddenly, the capacity of the road to admit vehicles is drastically reduced.

Peak time

From that moment on, despite the fact that traffic continues to rise, the number of cars actually drops. We pass into a congested traffic situation, where the black line showing the real traffic decreases and drifts apart from the demand curve (the discontinuous blue line, which continues to grow); So that more and more of the demand is unmet. Cars have to wait to be able to enter the main routes or they have to take a detour looking for an alternative road.

The most notable and damaging effects of traffic jams are:
A sharp decrease in speed (eg. on Madrid’s M-30 the speed drops from 55 to 15 MPH), which makes travel times three to four times longer.
speed evolution
Each car caught in the jam emits 80 percent more pollution (According to a study from Dr. Treiber from the University of Dresden).
pollution evolution
Once we have congested traffic, the situation seems insurmountable. Despite the fact that the number of cars on the roads decreases, the bottleneck means that traffic remains at a standstill. The only way to solve this challenge is to decrease the number of cars entering the road in the first place to avoid a traffic jam occurring.

The only solution is to remove a sufficient number of vehicles to avoid the roads from becoming congested.

Imagine that we managed to convince a certain number of people to offer the empty seats in their cars to passengers on their way to work. Thus removing several vehicles (from one to four, according to the number of passengers they carry) from the road.

This behavior change, which efficiently takes advantage of the sharing of the empty seats of some cars, helps in two ways:
All the people who need to get to work do so in fewer vehicles, which means fewer cars on the road and less traffic.
people in fewer cars
The effective capacity of the roads increases (according to the green area of the following graph).
extra capacity
This also has two effects on pollution improvement:
– First of all, with less vehicles on the road, there is less pollution.
– Additionally, by removing the extra cars, we prevent the pollution caused by traffic jams, which accounts for 80 percent more pollution than regular traffic.
How many rides do we have to share to avoid the traffic jam?

To keep a road decongested, we have to remove the excess cars that cause the jam (the number of cars between the saturation level of the road and the peak of the demand).

To achieve this, it would suffice to share a relatively low number of rides. The fact that each carpool can offer up to four passenger seats, is a multiplier effect that works in our favor.

In the worst case (if each car shares only one passenger, and still keeps three empty seats), it would be necessary to share as many cars as the surplus demand over the capacity of the road.

However, in the best case (when each car fills all its empty seats and carries four passengers) the situation is as shown in the following graph, and the number of cars needed is four times lower.

The rest of the vehicles can continue with one driver, and both these vehicles and the shared cars will enjoy moving traffic, with the advantages of less pollution and lower travel times.

In conclusion, traffic jams in the city cause 80 percent more pollution and three or four times longer travel times. We can easily avoid them, by simply sharing the empty seats in some cars and carrying passengers going in our direction.


Please note that this article expresses the opinions of the author and does not reflect the views of Move Forward

Carsharing vs. Ridesharing: Which New Technologies Solve Commuter and City Problems?

Technology will enable millions of people to use transportation means in a more efficient and sustainable way, solving traffic and pollution problems in cities.

Some benefits of technology are obvious: Car doors can now be unlocked remotely without physical keys. This innovation facilitates car rental by the hour, instead of by the day, and enables customers to return a car to a different lot from where they pick it up. GPS navigation can guide us safely to unfamiliar destinations, or streamline our routes for better convenience and cost savings. In the future, driverless cars will populate our streets — let’s hope they reduce the number of Single Occupancy Vehicles and clear the traffic jams that gridlock our cities.

Besides making it easier to hail a cab using an app, smartphone capabilities and social networks also make it possible for people to coordinate and achieve more efficient mobility by sharing private cars and rides. Thousands of programmers are creating new functionalities for improved mobility and when these applications are installed and used, it will lead not only to an accelerated innovation pace, but also to technology democratization, giving the user power previously reserved for enterprises. This is also called the new sharing or collaborative economy in which, in addition to the traditional consumer role, people acquire the new role of producer of goods and services to deliver to society.
Who’s who in the new businesses related to mobility?

New businesses are emerging around the world (like Uber, Lyft, Blablacar, car2go, Didi Chuxing) to capitalize on how consumers are using technology to get around. But there is still a lot of confusion about what these companies really do, and how they solve travelers and citizens’ problems.
It is very important to distinguish between sharing cars and sharing rides.

If I drive a car now, and someone else drives it later (for example, renting it by the hour ), that is car sharing. In the city, this saves parking space, and that’s all. There is little difference in the efficiency of using a taxi, whether you hail it on the street, or you call it by phone or by smartphone app.

However, if we find people with compatible paths and several of them go together in the same car (instead of going to work and each one driving his own car); this is ridesharing.
It’s much better to share a ride than to share a car.

Ridesharing is several times more efficient and sustainable than carsharing because it saves fuel and travel expenses by dividing the cost of using a single vehicle between several travelers. It takes the passengers’ cars out of circulation and helps to reduce traffic jams at peak hours, which can increase travel time by three or four fold and pollution by 80 percent. It also helps to solve parking and pollution problems in the city.

In addition, if the car is owned by one of the travelers and not an enterprise, there is no investment to recover and no profit. That is the true collaborative economy of the future, which reimburses the benefits of sharing to those who share, and provides additional city liveability and environmental benefits to the rest of society.
Instead of concentrating wealth on a few large companies (as has been the case with individual consumerism), the true collaborative economy (in which individuals share car rides, and take advantage of would-be empty seats) brings benefits to all of us.

By carrying extra passengers on your way to work or your travels around the city (or, better yet, going as a passenger in someone else’s car) you can get around with the comfort and speed of a cab, but at the lower price of public transit. As we remove cars from circulation, we overcome some of the most prevalent transportation problems in our cities: traffic jams, parking problems and air pollution.

Please note that this article expresses the opinions of the author and does not reflect the views of Move Forward

The Best Way to Move Around the City

The current technology along with modern urban transportation will offer new ways to move within cities more efficiently, with a reduced time and money expenditure, less energy wastage and less pollution.

Analyzing the way people move in big cities, a source of great inefficiency can be seen: most private cars are driven only by the owner; even though each one of them could carry five people, with almost the same power consumption and the same occupancy of space on the street.

Thus, there is an abundance of unused seats that can be leveraged to carry more people in fewer cars, thanks to the technology available today.

Benefits of filling empty car seats

In general, a fewer number of cars in circulation, will be a great relief not only for traffic congestion, but also for reducing the air pollution.

Traffic jams can be stressful to drivers every day, and result in loss of time and a higher than necessary fuel consumption. This usually happens during peak hours (when the majority of people go to work at nearly the same time), and they are caused by the simultaneous movement of a number of vehicles exceeding the capacity of the streets and roads.

In cities, pollution is mainly caused due to the exhaust of internal combustion engines in cars. We suffer its adverse effects, especially in areas with anticyclone weather conditions characterized by their weak winds with no clouds, which do not favour the dispersion of pollutants trapped at low levels, resulting in very poor air quality. Often, the authorities are forced to impose traffic restrictions to mitigate pollution.

All of these problems can be alleviated with a better use of the available means of transport; especially occupying as best as possible the empty seats of private cars which are already in circulation.

Advantages for those who share trips

In addition, people who harness the cars’ capacity utilization, sharing them during their daily trips, will benefit from substantial savings in time and travel expenses.

Passengers currently need to chain together various means of public transport, and spend more than an hour of their time to get from home to work. When these individuals travel as passengers in somebody else’s car, they enjoy a comfort and speed comparable to a taxi, while keeping costs as low as the bus fare.

Drivers, who are currently throwing money down the drain, by bearing all the costs of running a car on their own (amortization of the purchase, parking, fuel, insurance, taxes, maintenance etc.); will enjoy savings of up to 75 percent of such expenses if they share their ride with people willing to share costs, while on their way to work.

How technology can help to fill empty car seats

The wide use of smartphones and their data communication, navigation and location capabilities facilitate and greatly simplify the coordination of several travelers to share the cost of using a single car.

In this prototype, you can experience it. It allows to fill on the fly, the empty seats of the car with up to four passengers, and how much each one of them gets to save.

Once the advantages of urban real-time ride-sharing have been explained (the second BlaBlaCar generation), and the technology is proven to be usable, please tell us what else would be required for you to adapt to ride-sharing on a day-to-day basis? Share your thoughts in the comment section.

Please note that this article expresses the opinions of the author and does not reflect the views of Move Forward.