Putting a battery on the roof of the car so it can be replaced while driving; using solar power to maintain car temperature. All these sound like science fiction, however, right now they have all become reality due to the scientific ideas of students of Tianjin University. 

Recently, at the Final of the 11th National College Student Energy Conservation and Emission Reduction Social Practice and Technology Competition, young inventors focused on new energy vehicles to design creative ways of transportation for the future. Tianjin University teams harvested multiple honors at this event: the Qianli Electric Car, the car-roof long-lasting battery change technology, won a grand prize (top award), while Free Travel, the automatic window temperature control system based on a combination of photovoltaic power generation and semiconductor technology, won first prize. 

Battery charging has always been a key issue restraining electric vehicle development. At present, it is virtually impossible for electric vehicles to replace traditional cars due to a host of problems around charging: long charging time, short battery life, and inconvenient charging facilities. 

Undergraduate students of Tianjin University, with their imaginative minds, moved the batteries of electric vehicles to the car roof. It makes it possible to change batteries while driving. Their ideas attracted students of other majors and stirred creative sparks. They assumed that the battery can be charged at night to stagger the peak-hours. In addition, they also considered the possibility of recharging the battery with renewable energy such as photovoltaic panels and wind power. 

One of the team's instructors, Professor Zhao Jun of Tianjin University believes that this design can solve the key battery problems with electric vehicles that are slow to charge and have a short life. He also agreed that this design will not only save money but also can be quickly applied in metro cities where land usage is of the essence. Recently, the team built a model of the project car and completed tests. The competition jury believed their designs are more applicable than any other projects presently on the market. 

The students who invented the “automatic window temperature control system" really showed consideration to drivers. During the sizzling summer, the temperature within a car can become really intolerable, while during the freezing winter the windows can be covered by snow and frost. After internet research, their solution was to adjust the temperature by the use of solar power. 

This device is mainly powered by solar energy and uses semiconductor technology to effectively adjust the temperature inside the car, to improve driving comfort and to realize energy saving and emission reduction at the same time. In summer, the device will use solar power to cool the car and in winter, it can defrost the windows. This system is a fully automatic and no-button design; it can detect environmental temperature and automatically determine whether to open the cooling or heating circuits to allow fool-proof operation. 

"We still have a lot of ideas, such as optimizing the material and structure of the product, making the device lighter and thinner and using mobile control through the Internet”, said Liu Tianye, a member of the team. He said he hopes their ideas will bring beneficial changes to future travel.