Writer: H M Remi

In response to the Paris Agreement, the Hong Kong government published the report of Hong Kong’s Climate Action Plan 2030+ in 2017. The plan proposed that by taking the level in 2005 as the base, Hong Kong would reduce the city’s carbon intensity by 65% to 70% by 2030. In 2021, the government published another two reports, Hong Kong Roadmap on Popularisation of Electric Vehicles and Clean Air Plan for Hong Kong 2035, which asserted more mid-long-term plans for green transport development. For example, the government would form task force groups across departments to work with the transport industry, planning to push forward the progress of the new-energy-driven public transport within three years from 2021.

Generally, the railway is the backbone of the low-carbon public transport system, while the railway infrastructure in Hong Kong is advanced. Yet, its railway system cannot satisfy all the citizens’ travel needs due to the city’s extra dense population. People who are not living along the railway lines still need to depend on travelling by gas vehicles, like buses.

Evolution is the only way to keep surviving in this ever-changing world. KMB (Kowloon Motor Bus) has been doing well as a demonstration of this idea. It has joined hands with 48 business partners to roll out the “Decarbonisation Partnership” programme to answer the government’s green transport policy. In May 2021, KMB got the green light from the government to put the in-house-developed third-generation solar panel bus into service.

The third-generation solar panel installation was developed by KMB’s Engineering Team. The highlight of the enhanced installation is the “ultra-thin solar panel” pasted directly on the bus rooftop. These ultra-thin solar panels are only 2 millimetres thick with a heat insulation layer at the bottom. 14 pieces of these ultra-thin solar panels form a unit which covers 76% of the bus rooftop. These solar panels are so thin that KMB even calls them “solar films” in Chinese. As the nickname implies, the solar films are so light that they don’t need metallic frameworks for support since a unit of the ultra-thin solar “films” is only 70kg.

Currently, the solar films are primarily for cooling down the bus compartments. When a bus is not running its engine, the temperature of its compartment can rise to over 35°C. The solar films pasted on the bus rooftop can effectively cool down the compartments by 8°C to 10°C by powering the air conditioners and ventilation system with solar energy to extract the hot air from the compartments. A unit of solar films can generate 16.2 kilowatt-hours of electricity with an increase of 33% efficiency compared to the second-generation solar panel bus. It helps reduce fuel consumption by 5% to 8%, so every bus can use 11kg of fuel less daily, equaling a reduction of 6 tons of carbon emission per bus annually.

KMB would install ultra-thin solar panels on its 1,000 buses within 2022, making it the largest green bus fleet in Hong Kong. With the other 22 thousand solar panels installed in the bus depots, outdoor bus terminals, bus stop shelters and poles, KMB is generating 10 million kilowatt-hours of solar energy annually. It is equivalent to saving eight-minute of electricity consumption per person for the 7.5 million population of Hong Kong.

The design of solar cells becomes thinner and lighter. In the following article, we will introduce the inkjet-printed ultra-thin solar cells, which are light enough to attach to the soap bubble surface. Stay tuned!

Source:
https://topick.hket.com
https://www.hk01.com
https://www.climateready.gov.hk/files/report/tc/HK_Climate_Action_Plan_2030+_booklet_Chin.pdf
https://www.climateready.gov.hk/files/pdf/CAP2050_booklet_tc.pdf
www.kmb.hk/tc/news/press/archives/news202105143826.html
https://www.kmb.hk/en/news/press/archives/news202206094109.html

Image Source:
https://www.kmb.hk/en/news/press/archives/news202105143826.html