Transportation Deployment Casebook/2015/Electric Bikes in China

= Qualitative Analysis =

Mode Description
Electric bicycles look like fuel-power motorbike, but they are actually bicycles with electric motors. Most electric bicycles have pedals, drivers can use them as ordinary bicycles when the battery power runs out. But there are also electric bicycles without pedals. The highest speed of electric bikes is about 45 km per hour. Because electric power is cleaner and cheaper than gasoline power, electronic bicycles are more environmentally friendly than fuel-power motorbikes or vehicles.

The Scene
As we know, China is titled “the kingdom of bicycles” because it has the largest bicycle ownership in the world. Bicycle came to Chinese’s life as early as 1868. The first bicycles showed up on the road of Shanghai. After 1920s, the number of bicycles increased rapidly. Because during those years, few people in China could afford a car. The demand for fast travelling was large, and bicycles were not expensive and also much faster than walking, so it became popular in China in a really short time. In 1950s, bicycles were regarded as one of "three bigs"---along with a sewing machine and wristwatch. And another traffic mode before electric bicycles is motorbikes. They use gasoline or diesel so their emission is quite harmful pollutant. As China's economy improves, there are more and more cars on the street. This causes serious mingle traffic flow of bicycles, cars and motorbikes. In the urban area, motorbikes have almost the same speed as cars. So serious accidents may happen when their travel trajectories conflicts because drivers violate the traffic rules. Many people dies from accidents every years during that period. That’s why several major cities in Chinese started to restrict the use of motorbikes on the road in 1990. The emergence of electric bicycles fills the gap created by the banning policy on motorbikes. Actually, it showed up in Chinese market before the implementation of banning policy. Because they have electric motors, they can run on the vehicle lanes when they have power. If the power runs out, they can change to the non-vehicle lane. Because electronic bikes are lighter with smaller inertia, they can easily change lanes and turn around.

Invention
The earliest invention of electric bicycles can be 1898, and the first electric bicycles was invented by transferring the power from the electric drive to the rear wheel using a belt. There are various patents documented in U.S. At the beginning, most batteries were the lead acid type These batteries were really heavy and bulky. The only benefit of lead acid batteries was that they are less affected by temperature compared to newer types of batteries we use today. And at that time, this kind of batteries was expensive so that it was nearly impossible to manufacturing electric bicycles.

Battery
The technology of electric bicycles comes to manufacturing mainly because of the mature of the technology of rechargeable batteries. The batteries in use include sealed lead-acid (SLA), nickel-cadmium (NiCad), nickel-metal hydride (NiMH) or lithium-ion polymer (Li-ion). The lifespan of a battery pack will largely influence the travel distance of electric bicycles. As the lifespan of the battery become larger, the practicability of electric bicycles is increased.

Torque sensors
The development of torque sensor is also a building brick of inventing electric bicycles. A Torque Sensor is a transducer that converts a torsional mechanical input into an electrical output signal. There are two kinds of torque, static torque and dynamic torque. The latter one is harder to measure. The use of the torque sensor in electric bicycle is to test the signal created during motor rotates and the controller can use this signal to make the balance of human-power and electric power. This technology was developed in the late 1990s. The inventor from named Takada Yutky registered a patent for it in 1997. And in 1992, a company named Vector Services Limited started to sale electric bicycles named ‘The Zike’. The structure of this vehicle was simple, a NiCd battery and a 850g permanent-magnet motor were added into the frame member.

Early Market Development
The first time that electric bikes showed up in the market of China was 1985, but it was imported from Japan. In 1995, the first batch of electric bicycles produced by Chinese company were put into the market. The presence of electric bicycles didn’t attract much attention to the market. Motorcycles were still the most popular vehicles on roads. They ran on the roads of most cities because the bans toward motorcycles had not been implemented in the whole country. So the motorcycles still have larger market share than electric bicycles. During the early phase of market development, which was 1995-1999 exactly, all the Chinese electric bicycles companies were focusing on making technical innovations, such as the technologies of batteries, electric motors, chargers and controllers. The amount of electric bicycles in the market was small so only a few customers noticed this kind of vehicles, which were cheaper and lighter than a ordinary motorcycle. It is said that electric bikes are the first type of electric vehicles that achieve mass production. It accurately describes the situation at that time in Japan instead of China.

The Role of Policy in Birthing Phase
During the birth stage of electric bicycles, the banning policy to motorcycles in major cities greatly helped electric bicycle companies to enlarge its market share. In 1985, Beijing became the first city which bans motorcycles in urban area because of high accident rate. Then in 2002, Hangzhou, a famous tourism city in China, also started to ban motorcycles. In 2004, Guangzhou followed Hangzhou and started to implemented the same policy. By 2015, there has been 185 cities banning motorcycles on the roads. There are mainly two ways that the government uses to remove motorcycles from the roads. One way that most major cities use is to stop authorizing motorcycles licenses in a time point. And with the aging of the existent motorcycles, they would die out gradually. Another aggressive way the government use is to ban all the motorcycles with or without licenses at the same time. Because of the incomplete of the transit system in China, most traffic demand from people who are deprived of the right to ride motorcycles cannot be satisfied at all. Although some extra traffic demand from city motorcyclists can be settled by adjusting the timetable of buses or subways, the demand from rural motorcyclists cannot be settled in this way because there were few bus lines connecting the rural and urban areas in the late 1990s or early 2000s. So electric bicycles are great replacements for former motorcycles. The description given by industrial standard is that the electric bicycle is a special kind of bicycle, using electricity as auxiliary energy resource, with two wheels and can be driven by manpower as well as electric. This description distinguished electric bicycles with motorcycles in order to effectively circumvent the restrictions on motorcycles. In technical aspect, the batteries of electric bicycles at this time can only afford about a 30-km’s travel. The longevity of the battery is also short, the climbing ability is weak.

The Growth of the Mode
During 2000 to 2004, the electric bicycle factories made greatly development. Because of the banning policy to the traditional motorcycles, the sale of electric bikes became increasingly large. With the breakthrough in key technologies and the development of the performance of electric bikes, they became the perfect replacement for motorcycles and bicycles. And electric bicycles attracted more consumers because of its cheapness, convenience, swiftness and environmentally friendliness. Besides, this kind vehicles are not restrained by policies. Electric bikes can running on the road as an auto vehicle when the motor is on, or people can ride it on bicycle lane just as an ordinary bicycle, so it gain popularity in both urban and rural areas. As the demand for this kind of vehicle became larger, the older factories expand its scale quickly and many new factories came to this profitable field. All these lead to the rapid rise in the production of electric bicycles. Jiang Su province, Zhejiang Province and Tianjin became three largest industry-intensive cities in China. Other industries related with electric bicycles also got well developed, such as battery industry and motor industry.

Development during the Mature Phase
From 2005 to 2007, the scale of economic formed gradually. And the presence of competition between companies inspired the progress and expanding of rear-ending technologies. The data shows that during this period, the longevity of batteries increased by 5 times, the production efficiency increased by 30 percent, and the climbing ability and loading capacity rise by 3.5 times. At the same time, the cost of manufacture sharply fell. The batteries evolved from simple lead-acid cell to multiple types of batteries. The emergence of lithium battery makes electric bicycles lighter and simpler. Besides, the invention of permanent magnetic brushless motors also brought the revolution in electric bicycle industry. According to a ranking about top 10 vendors in 2011 by production volume, three vendors are Chinese vendors including the first and the second places. The large amount of electric bicycles attracts the attention from traffic managers. Electric bicycles at this time was not the same vehicle as those in 1990s at all. According to national standard, electricity can only serve as an auxiliary power, and the speed should be below 20 km/h. But as the rapid evolution of electric bicycles, their speed is much faster than 20km/h, even reach the speed of a motorcycle. The pedals became useless or just disappeared so that electricity played the role as the main power for electric bikes at the end. These may be good news, but inconsistent with the high speed, the break performance of electric bicycles was still in a relatively low level. Most electric bicycles still used the same break mechanism as low-speed bicycles. So they were more likely to turn over during emergency brake. Even some people who were incapable to ride a bicycle brought an electric bike because they were nearly the most easy vehicles for any people to learn. In this way, many road killers came into the urban roads and city streets. With a lack of driving education, electric bicycle drivers are more likely to violate the traffic rules. Traffic managers try to issued regulations to restrict the use of electric bicycles. But it’s much more difficult to restrict electric bicycles than restrict motorbikes. Because it’s easy to restrict the use of motorbikes by stopping issuing licenses, but most electric bikes don’t have a license. According to the national standard, the weight of electric bicycles should be less than 40 km/h, the speed should be less than 20 km/h. If not, the driver need get a driving license and buy special insurance. The problem is that after one person buy an electric bicycle with a maximum speed as 20 km/h, he can easily refit it with a new motor and improve the maximum speed up to 50-60 km/h. Besides, it’s easy to cut the energy supply to motorbikes, which is the gasoline while it’s much harder to cut the energy supply for electric bikes because they get power from regular electric sockets. All of these reasons make it very hard to get rid of the electric bikes on the street completely.

= Quantitative Analysis =

Analysis Method
We use S-curves to identify each phase of the life cycle. And we use data to estimate a three-parameter logistic model.


 * $$Y(t) = \frac{K}{1 + e^{-b(t-to)}}$$


 * S(t) is the status measure, (e.g. production or ownership)
 * t is time (usually in years),
 * to is the inflection time (year in which 1/2 K is achieved),
 * K is saturation status level,
 * b is a coefficient.

Data Source
There are two indexes that can reflect the demand for electric bicycles in China, one is the production, the other is the ownership. Ownership means the number of users, which directly shows how useful the electric bikes are. But the data about the ownership is hard to find and is not accurate because during the first stage of development, very few data about the ownership of electric bicycles was recorded. So it leads to the missing of data during the period from 1999 to 2003. Then from 2004 to 2013, Chinese Cycling Association would publish the data of electric bicycle ownership every year. Another index is the production of electric bicycles. This data is easy to get because it’s one of the most important index for Chinese electric bicycle manufacturers, so there are many production reports online.

Electric Bicycle Production
The fitting curve of electric bicycle ownerships shows that 2009 is the year with largest growing speed, and we are approaching the summit which is about 184.8 million at 2020. And there are already 181.6 million electric bicycles in China, so the growing of ownership will not last for too long. This conclusion accords with the actual situation in China. The government is aware of high accident rate of electric bicycles in China and many cities have banned electric bicycles in urban area. And with the implement of new national standard about the electric bicycles, the restriction on this kind of vehicle would become larger and larger. So the growing speed of the ownership will not as large as that in 2004 to 2009.

Electric Bicycle Ownership


The fitting curve of electric bicycle ownerships shows that 2009 is the year with largest growing speed, and we are approaching the summit which is about 184.8 million at 2020. And there are already 181.6 million electric bicycles in China, so the growing of ownership will not last for too long. This conclusion accords with the actual situation in China. The government is aware of high accident rate of electric bicycles in China and many cities have banned electric bicycles in urban area. And with the implement of new national standard about the electric bicycles, the restriction on this kind of vehicle would become larger and larger. So the growing speed of the ownership will not as large as that in 2004 to 2009.