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Hydrogen Pathways Research
- Current Research: Jonathan is researching the transition to electric bikes in China, its causes, and the consequences on urban transportation, battery technology, and future market growth of this mode in other countries. He is a visiting scholar at Tongji University's College of Automotive Studies in Shanghai.
- This investigation on the causes and consequences e-bikes in China
will give policy makers a better understanding of the implications this
transportation mode has on future mobility in China. The results will
shed light on controversial questions facing Chinese policy-makers such
- Should e-bicycles be encouraged or banned from city streets?
- Will e-bikes just be a stepping-stone to cars or will they last?
- What are the implications of e-bike market growth on battery technology improvements, and will these improvements carry over to the automotive sector?
- What can the evolution of e-bike technology over the past 10 years tell us about the transition to personal cars in China over the next 30 years, and the transition away from petroleum fuels in the US and around the world?
Summary of Electric Bikes in China
- 1. What are E-Bikes?
In China, electric bikes or e-bikes includes two-wheel bikes propelled by human pedaling supplemented by electrical power from a storage battery (bicycle-style), and low-speed scooters propelled almost solely by electricity (usually with perfunctory pedals to satisfy legal definitions) (scooter style). Typical bicycle-style and scooter-style e-bikes are shown in Figure 1.
- Fig. 1: Bicycle style and scooter style electric bikes
The technology of both types of e-bike is similar; main components include a hub motor, controller and valve-regulated lead-acid (VRLA) battery. Bicycle-style e-bikes typically have 36V batteries and 180-250W motors. Scooter-style e-bikes typically have larger 48V batteries and higher-powered motors (350-500W). Electric bikes are regulated not to exceed 20km/hr, but many, especially scooters, can travel at speeds in excess of that limit and some are advertised to go 40km/hr.
In general, e-bikes consume 1.2-1.5 kWh of electricity per 100 km. On a single charge (typically 6-8 hours), they can travel 25-50 km. Electric bike batteries are recharged from a standard electrical outlet and thus require no new re-charging infrastructure. (Is it true that battery packs are removable so that charging does not need to occur where the bike is parked? If so please add.)
E-bikes are gaining an increasing share of two-wheeled transportation throughout China, as they provide an inexpensive and convenient form of private mobility. In many cities, like Chengdu and Suzhou, have even surpassed bicycle mode share. Annual sales in China reached 16-18 million bikes/yr in 2006, up from only 40,000 in 1998 [1, 2]. There are an estimated 30-40 million e-bikes in China based on annual sales over the past 5 years.
The cost of owning and operating an e-bike is the lowest of all personal motorized transportation in China. The following figure and table compare the life-cycle cost of an e-bike compared to competing modes namely other commonly used two-wheeled vehicle modes and bus public transport.
- Fig. 2: Cost comparison of common urban travel modes in China (Weinert et al. 2006)
- 2. The Success of E-bikes in China and its Environmental Implications
2.1. Factors Contributing to E-bikes Success
E-bikes have become a popular transportation mode in China for the following reasons:
1. E-bike technology, specifically motors and batteries, improved significantly during the late 1990’s. Simple technology, a vast supplier base, and weak intellectual property protection made it easier for e-bike makers to enter the industry, increasing competition and driving prices down.
2. Due to improving economic conditions nationally, incomes of urban households and the share spent on transportation both rose considerably.
3. E-bike prices decreased, gasoline prices rose and electricity prices in rural areas dropped, making e-bikes more competitive economically with alternatives like gasoline-powered scooters and bus.
4. National and local government policy motivated by energy and air quality issues created favorable conditions for e-bike growth. Banning gasoline powered motorcycles in large city centers removed the most competitive mode from the choice set.
5. National e-bike standards with loop-holes and flexible guidelines created a rich opportunity for manufacturers to create e-bikes that appealed to more users, namely, scooter-style electric bikes.
6. Due to changes in urban form, bicycles and buses became less attractive due to increasing trip length and increased congestion. This made trips difficult to traverse by bicycle and slow by motorized modes, particularly buses and taxis.
2.2 Environmental Impacts of E-bikes in China and Policy Recommendations
E-bikes are an extremely energy efficient mode of personal transportation with zero tailpipe emissions. They are having positive effects in cities battling poor air quality by displacing gasoline-powered scooters. They also have a positive impact on climate change since in-use carbon emissions per km travelled of an e-bike are roughly four times lower than scooters and 14 times lower than cars, as seen in the following figure.
- Figure 3: Carbon Emissions of Transportation Modes in China (Cherry 2006)
While e-bikes provide zero tail-pipe emissions, they do emit pollution from power plants, which are 75% coal fired in China (Cherry 2006). This results in increased emissions of certain pollutants, particularly SO¬2, which is particularly problematic in Chinese cities. Other pollutants are low, compared to alternative modes (Cherry 2006).
Lead emissions from battery production and recycling in China is the most serious environmental problem with e-bikes. Lead emissions per passenger kilometer are several orders of magnitude higher for electric bikes than for buses (Cherry 2006). Because of poor production and recycling practices within the lead and battery industries, it is estimated that 30-70% of the lead in a battery is lost to the environment.
In order to improve the environmental performance of e-bikes, policies should focus on reducing lead emissions associated with e-bike use. These policies include:
1. Stricter standards in the domestic lead production and recycling industry to limit lead contamination in the surrounding local environment.
2. Encourage further consolidation of the lead production and battery manufacturing industry. This will make it easier for quality and environmental standards to be enforced
3. Provide financial incentives for e-bikes using advanced technology batteries such as Lithium-ion and Nickel metal-hydride. These batteries cost 4-7 times VRLA batteries, but have 2-3 times longer lifetime and 2-3 times higher energy density.
1. Weinert, J., Burke, A.F., Wei, X.Z. (2007) “Lead-acid and Lithium-ion Batteries for Electric Bikes in China: Implications on the Future Growth of Electric-drive Vehicles”, (submitted to Journal of Power Sources), pp.16
2. Weinert, J., Ma Z.D., Yang X.M., Cherry C. (2007) “The Transition to Electric Bikes in China: Effect on Travel Behavior, Mode Shift, and User Safety Perceptions in a Medium-Sized City”, Transportation Research Board (TRB) Annual Conference Proceedings, Washington DC, Jan 20-24, pp.17
3. Weinert, J., Ma Z.D., Cherry C. (2006) “The Transition to Electric Bikes in China: History and Key Factors for Rapid Growth”, Journal of Transportation Special Issue: Motorization in Asia, pp.26
4. Cherry, C. (2006) Implications of Electric Bicycle Use in China: Analysis of Costs and Benefits. UC Berkeley Center for Future Urban Transport-Volvo Summer Workshop, Berkeley CA, 2006.
- (In Chinese)
Jonathan Weinert has been actively engaged in the energy and transportation industries for the past eight years and is now applying this experience in urban China. In July 2005, he moved to Shanghai to work with researchers at Tongji University on analyzing hydrogen infrastructure costs In March 2006, he began researching electric bikes in China (see description above).
He completed his Master's Degree in Transportation Technology and Policy at UC-Davis in March 2005 and advanced to PhD candidacy in July 2005. His Master's Thesis focused on the near-term cost of hydrogen fueling stations for fuel cell vehicles. In 2004, he played a key role on the Governor's California Hydrogen Highway Blueprint Team as Station Cost Team Leader. He spent Fall 2003 interning with the South Coast Air Quality Management in Los Angeles to learn about policy-making within a regulatory agency. This internship resulted in a case study report on the development of the LAX airport hydrogen fueling station.
Before joining UC-Davis Institute of Transportation Studies, Jonathan worked at Ford Motor Company helping them develop their California Fuel Cell Partnership office, home to several fuel cell vehicles. Prior to this, he worked in Detroit, MI with Delphi Automotive’s Energy and Engine Management group.
He graduated with a B.S in Mechanical Engineering from the University of Michigan in 2000. His interest in energy efficiency and clean energy technologies spawned from his experience working at the UofM Industrial Assessment Center and studying renewable energy in Sydney at the University of New South Wales.
Jonathan plans to complete PhD in Summer of 2007. After completing his degree, he would like to join industry working internationally in the energy or transportation sector. His goal is to introduce clean transportation fuels and technologies to developing parts of the world.
PhD Candidate, Transportation Technology & Policy, University of California, Davis. (current)
Certificate in Business Development (non-degree) Graduate School of Management, University of California Davis (2005) (Fellow)
M.S. Transportation Technology & Policy, University of California, Davis. (2005) Masters Thesis: Evaluating the Economics of Hydrogen Fueling Stations. Business Development Fellow (2004-05) Eno Leadership Development Fellow, 2003, Chevron-Texaco Fellow 2002-03, IGERT Fellow (sponsored by NSF) 2002-04,
B.S., Mechanical Engineering, University of Michigan, 2000. Jonathan’s undergraduate education focused on energy systems; included study at University of New South Wales in Australia.
Halter Financial Advisory Group: Intern, (Spring-Summer 2007), Shanghai, China
South Coast Air Quality Management District: Hydrogen Program Specialist (Fall 2003) Diamond Bar, CA
Ford Motor Company; Project Engineer (2002-03), California Fuel Cell Partnership Office, West Sacramento, CA
Delphi Automotive; Test Engineer (2000-2002) (Brighton , MI)
HEC Energy and Design Services, Intern; 1998 (Boston , MA)
Industrial Assessment Center ; Student Energy Analyst, Audit Leader; 1997-2000 (Ann Arbor, MI)
Activities and Interests
Institute of Transportation Studies Student Council Chair, 04/05
Mentor for UC Davis undergraduate “Women in Engineering” Program, 2005,
Director of “UC-Davis IGERT Conference on Advanced Transportation Technologies”, 2003
Jonathan likes teaching. In China, he has led several discussion workshops with Chinese students on a variety of cross-cultural topics. In the US, he has led workshops with both students and teachers on fuel cell technology, developed educational materials for teachers, and mentored students. He has demonstrated fuel cell vehicles to over 1,000 students and teachers throughout the US and Canada.
When not researching e-bikes, Jonathan likes playing piano & guitar, dance, and exploring the lesser-known quarters of Shanghai and outer-reaches of China.