Expert Talks for Secondary School

To help broaden the knowledge of the younger generation in the fields of energy and environment, the School of Energy and Environment, City University of Hong Kong, offers a number of talks to the secondary school students in Hong Kong. Given by the professors in the School, the talks can be conducted in the CityU campus in Kowloon Tong or the secondary schools as requested.

Interested secondary schools are welcome to contact the School at the following methods for arrangement.

By email:
By fax: 3442 0688

Topic & Brief Description Language Speaker*

Air Pollution and Cooking

Particulate matter (PM) will induce health issues and hinder the visibility of the cities. Part of the “contributions” lies on the restaurants. Through the talk, you will understand how and why the cooking process in restaurants will create potentially hazardous PM and adversely affects the environment and human health.


Prof. Chak K. CHAN

Alternative Power Sources for Vehicles

Conventional vehicles are driven by the combustion of gasoline and diesel, which process releases CO2 emissions and causes harm to the environment. In order to mitigate the emission issue, the Hong Kong government has set the goal to achieve carbon neutrality by 2050 and launched the “Climate Action Plan 2030+”. For that, developing clean power sources to replace the currently dominant internal combustion engine is critical. In this talk, two advanced technologies, i.e., lithium ion batteries and fuel cells, will be introduced as alternative power sources for vehicles. We will give a general picture of their working principles, current progress, technological bottlenecks, future development, and we will answer why those technologies can be successfully applied in vehicles (e.g., Tesla and Toyota).


Dr. Jian WANG

Building Energy Efficiency – Energy Saving is Just around You

Buildings consume a huge amount of energy, responsible for 90% of the total electricity use in Hong Kong. There are many energy management opportunities (EMOs) for building energy efficiency. They can not only lower your energy bill, but also reduce your carbon footprint. Some EMOs requires significant renovations for systems or buildings, while many EMOs are easy to implement. In this talk, we will discuss various EMOs in our daily life and you will obtain effective energy savings right away.


Dr. Wei WU

Carbon Capture and Storage – An Effective Way to Combat Global Warming

To meet the high demand for energy, the burning of fossil fuels including coal, oil and gas has been increasing since the beginning of industrialisation and will continue to dominate the energy supply for the foreseeable future. Burning fossil fuels leads to emissions of carbon dioxide and other greenhouse gases, which contributes to global warming. One effective way to mitigate global warming is to capture and store the emitted CO2 to prevent it from polluting the atmosphere. This talk will introduce carbon capture and storage technology with a particular focus on adsorption technology for CO2 capture.



Climate Change Feedback

Why is the polar bear being used as a climate change mascot? Why not penguins? This talk will cover why the Arctic is warming faster than anywhere else on the Earth and what feedbacks are at work in the climate system. Discuss how various natural phenomena such as carbon dioxide, sea ice, forest fires, and clouds interact with each other. Also, it would be delivered on how climate change is going in the near future and what we can do to stop global heating.

English Dr. Jinsoo KIM

Economic Thinking in Energy and Environmental Policy

Pollution and global warming are two of the hottest issues in current public and policy debates. Governmental bodies – local, regional and international – have implemented a series of policies to tackle these issues. In this talk, the speaker will discuss how to understand and evaluate these policies from the perspective of economics.



Electric Vehicle in Our Life

Electric vehicles (EVs) becomes more popular in our daily life. Different from conventional internal combustion engine (ICE) vehicles, EVs have more potential to connect with our life by human-machine interfaces like personal computers. In this way, EVs would have more intelligent features for near future application, such as autonomous driving, autonomous navigation, etc. This talk will introduce emerging technologies of future EVs for our life.


Dr. Chunhua LIU

Environmental Justice and Quality of Life

In this talk, the speaker will first apply the theory of justice to analysing the distribution of environmental impacts at a global, country, regional, and neighbourhood level. Then the speaker will review, for correcting environmental injustice, public protests and environmental movements have pressured the government to change the paradigm of development. Lastly, the speaker will discuss how quality of life and happiness have guided some pioneer countries in their national development planning. Of course, the implications for Hong Kong will also be discussed.


Dr. Wanxin LI

Extraction of Molecular Hydrogen from Wastewater

Molecular hydrogen (H2) is a clean energy carrier with high energy density. It is also a chemical reagent for petroleum refining as well as ammonia production. Currently, major production way is based on fossil fuel transformation, including the steam reformation of methane. Water splitting is another popular potential way in producing H2 with low or zero carbon footprint but water decomposition is a thermodynamically challenging reaction. Wastewater containing organic pollutants such as pharmaceutical wastewater, leachate, and industrial process water, on the other hand, can be potentially used to produce H2 with reduced energy requirement during the oxidative removal of such organic carbon inherently present in the water stream. We examine a few potential methods to simultaneously oxidise the organic component (pollutant) in the water and reduce the proton to liberate molecular H2. In particular, electrocatalysis, photocatalysis and photoelectrocatalysis are developed. Challenges encountered in this waste-to-energy conversion process will be tackled.


Prof. Yunhau NG

Fail-Safe vs. Safe-To-Fail Systems: How to Design Resilient Infrastructure?

Large direct and indirect impacts across national and international boundaries of natural disasters like 2011 Tōhoku earthquake and tsunami, infrastructure failures, like the 2001 U.S. North-East blackout, epidemics like the H1N1 influenza, terrorist attacks like the 9/11, and social unrests like the Arab Spring are indicative of the vulnerability associated with growing complexity. There is an urgent need to understand resilience of complex systems to move from the fail-safe paradigm to safe-to-fail approached to engineering. This talk will introduce the concept of resilience along with its various definitions; discuss the relationship between resilience and sustainability; and present ways to build resilient systems of the future.


Dr. Shauhrat CHOPRA

Future Advanced Energy Efficient Technologies

In modern life, people spend a large portion of time in indoor environments. A huge amount of energy is consumed in order to provide a comfortable indoor environment. For example, almost 90% of the total electricity in Hong Kong is consumed by buildings at end-use level as stated by the government. Among different electricity end-uses, thermal systems contribute to a significant consumption of electricity in buildings, with 36% of electricity used to power space conditioning and refrigeration systems. In this talk, the speaker will talk about some new future cooling schemes for use in buildings, followed by a discussion of the current research challenges in energy efficient cooling technologies.


Dr. Edwin TSO

Green Energy from Photosynthesis 

Photosynthesis is a natural process found in plants and many types of bacteria and algae by which the organisms utilize sunlight, water, and CO2 to produce sugars. Thanks to the global energy and climate crisis we witness today, we are only now stepping into developing sustainable technologies for solar energy harvesting and CO2 capture. However, because of the billions of years of evolution, nature has mastered and fine-tuned the process of harvesting solar energy and capturing atmospheric CO2 by means of photosynthesis. This talk will look at how photosynthesis works and what we can learn from this natural process in developing bioinspired and biohybrid energy technologies. We will explore the concepts of Artificial Photosynthesis and Semi-Artificial Photosynthesis and their implications for solar energy harvesting.

English Dr. Sai Kishore RAVI

How to Turn Food Waste into Chemicals and Materials?

Current technologies for the production of chemicals, materials and fuels depend mainly on fossilised hydrocarbons. However, the depletion of fossil resources and the increasing concern of environmental issues have created the need for the development of the sustainable alternatives based on renewable raw materials. Many chemicals that used to produce via chemical processes can now potentially be generated biologically from renewable raw materials. The talk will introduce a novel food waste-based biorefining strategy for the production of nutrient-complete feedstocks for the production of biochemicals, biofuels and biopolymers.


Dr. Carol LIN

Hybrid Organic-Inorganic Materials for Solar Energy Application

Hybrid organic-inorganic materials will play a critical role in the development of advanced functional materials. They can be broadly defined as molecular or nano-compositions with organic and inorganic components. Hybrid perovskite materials have been rapidly adopted for solar energy applications since 2009 because of their impressive features, such as a high absorption coefficient and long exciton diffusion length. We are right at the start of this material revolution, which is expected to have a positive influence on renewable and alternative energy. The speaker will introduce the basic knowledge related to hybrid materials, photophysical properties, photoelectrochemistry and solar cells.


Dr. Sam HY HSU

Is the Air in your House Safe?

Many people may think that indoor air is safer than outdoor air. They close the windows and turn on their air conditioners for the whole day. However, indoor air is not always clean. In fact, there are a number of pollutant sources found in your house.

Some indoor pollutant sources are quite “obvious”, such as cooking fumes in the kitchen and cigarette smoking. However, some of them are hiding secretly and harm our health. Indoor air quality is a critical environmental issue that all of us should be aware of. In this talk, I will discuss where they are and how to mitigate the dangers of poor indoor air quality.

Cantonese Prof. Chi Keung Alvin LAI

Marine Water Environment in Hong Kong

Hong Kong is surrounded by coastal and marine environments, which are very unique. Human and marine are inter-connected and closely related. What are the interesting marine environments in Hong Kong? How the human activity in Hong Kong can affect the marine environment, and conversely, how the marine environments can provide important resources to people in Hong Kong? In this talk, I will highlight some of the very unique marine environments in Hong Kong, especially with respect to the protection of marine environment.


Prof. Wenxiong WANG

New Technology for Drinkable Seawater

Water is everywhere: in the air, clouds, rivers, oceans, ice, plants and inside the Earth. However, 97% of water is saline and in the oceans. Therefore, converting seawater into drinking water can be considered one of the best alternative water resources: the new desalination plant will be located in Tseung Kwan O, Hong Kong, in the near future. This talk will review water technologies and novel technologies that have the potential to achieve sustainability for desalination. It will also discuss the next generation of desalination in three folds: increase water recovery (reduce brine/concentrate), lower energy use, and increase resource (minerals) recovery.


Dr. Alicia AN

Renewable Energy - The Only Way to Go for a Sustainable Future

Our heavy reliance on fossil fuel and nuclear power has caused serious environmental impacts and energy crisis. The ultimate solution is to switch to renewable energy, such as solar, wind and ocean energy, for achieving a sustainable future. In this talk, the Speaker will give an overview of the renewable energy resources and technologies, followed by a discussion of the upcoming challenges and opportunities in the renewable energy industry.


Prof. Michael LEUNG

Sustainability Thinking on Waste Management

The phenomenon of “trolleys and the elderly” is typical in Hong Kong and Asia, behind it are the coupling economic (e.g., incomplete pension system), social (e.g., urban inclusiveness) and environmental (e.g., circular economy and its trade-offs) challenges. Therefore, we need a thinking from the perspective of sustainability (the so called "Triple bottom line", in terms of economic efficiency, social equity and environmental responsibility), to design an inclusive waste management system. This talk will take you a tour to see the sustainability challenges for integrated waste management, and how we could tackle such challenges, with the development of an inclusive policy making.


Dr. Liang DONG

Tackling the Pressing Energy Challenges: from Fundamentals to Real-life Examples

In the modern society, we consume a large amount of energy every day. The ever-increasing energy consumption and reliance on the fossil fuels have resulted in pressing challenges like energy shortage and environmental problems. Addressing these issues requires innovative solutions in areas like renewable energy technologies, energy efficiency and pollution control. To develop such solutions, one needs knowledge crossing the boundaries of traditional scientific and engineering disciplines. In this talk, we will discuss some interesting in scientific and engineering knowledge. Then, we will highlight innovative examples to tackle the energy challenges we face nowadays.


Dr. Patrick SIT

The Afterlife of Smartphones

Where do smartphones go when they “die”? Come find out! This talk explores how smartphones are recycled and what kind of valuable resources can be recirculated back to the electronic industries. We will also talk about how smartphone companies can improve their future product designs to enhance smartphone’s recyclability.

English / Cantonese

Dr. Jason LAM

The Chemicals We Are Discharging into the Environment

Many chemicals and chemical products are considered essential to modern life because of the benefits they provide to human beings. Some of them, if not most, will inevitably enter the environment through acts of nature, accidental spills, or intentional discharges. Several chemicals of concern will be discussed to illustrate how our daily life can impact ecological health by discharging them into the ecosystem.

English Dr. Henry HE

The Essential Role of Fundamental Laboratory Studies in Solving Today’s Air Pollution Issues

Air pollution poses serious impacts on climate, human and ecological health. Addressing today’s most pressing and complex air pollution issues will require a three-legged stool approach of laboratory experiments, ambient observations, and modeling studies. Each leg of the stool is only as stable as the fundamental chemistry that underpins it. This talk will discuss how laboratory studies serve as an essential bridge between ambient measurements and air quality models, and provide the fundamental physics and chemistry of the underlying mechanisms of phenomena observed in the field, which is the basis for generating physically meaningful parameterizations for use in air quality models.


Dr. Theodora NAH

The Science Behind Haze

Haze is one of the most important forms of air pollution which causes harmful effects on human health and reduces visibility. The formation of haze is related to pollutant emissions from a variety of natural and human-made sources, and more important, the meteorological condition and atmospheric chemical reactions. The talk will focus on the basic chemistry and physics related to haze formation, and the corresponding scientific strategies on solving haze pollution.


Dr. Xuan WANG

Turning Food Waste to Energy

Everyday Hong Kong generates 3,500 tons of food waste. Sending food waste to landfills will not be sustainable in the long run. Instead, we can use biological processes to turn these organic matters into energy. Let's find out together how we can make use of biology to make this happen.


Dr. Patrick LEE

UN Sustainable Development Goals (SDGs) and Ourselves

The Sustainable Development Goals (SDGs) are a collection of 17 interlinked global goals designed to be a “shared blueprint for peace and prosperity for people and the planet, now and into the future”. They were set up in 2015 by the UN general Assembly and are intended to be achieved by 2030. These goals look at the economic development, innovation, environment, justice, equality, life below water and on land, etc. They touch upon everyone’s life. Their achievement also depends on each one of us, the citizen of the plant. In this sharing, we’ll analyze the goals that affect People, Planet, Prosperity, Peace and Partnership. We’ll discuss about how we can do to help those SDGs to be achieved.

English Prof. Guohua CHEN

Urban Solar Photovoltaic Technologies

The Hong Kong government has set an ambitious goal of reaching carbon neutrality by 2050. A critical strategy in its overall planning is to increase the deployment of renewable solar energy. In this talk, I will discuss how we can rely on technological innovation to tackle this grand challenge; particularly, we have identified a new generation of printable, flexible, transparent, and color-tunable solar cells as the most prominent photovoltaic technology to promote solar energy deployment in Hong Kong.  Such a new solar cell technology can be integrated as tinted solar windows, façades, or curtains with buildings to generate significantly more solar electricity in an urban city, which usually has limited lands and rooftops for installing conventional silicon solar panels.

English / Cantonese Prof. Angus Hin-Lap YIP

Urbanisation and Climate Change in Asia: Impacts and Adaptation

During the last 20 to 30 years, because of rapid economic growth, extensive areas of agricultural and rural land in many countries in Asia have been transformed into cities. Such changes have substantially modified the exchanges of atmospheric properties between the land surface and the atmosphere. In addition, these cities, many of which have been known as mega-cities, generate additional heat and pollutants that are injected into the atmosphere. Furthermore, many of these cities have been developed over a short period of time, and hence city planning in general has been minimal. All these consequences of urbanization have great impacts on the regional climate, which will also be affected by global climate change. Thus, cities in Asia have suffered, and will likely continue to suffer, significantly in terms of climate hazards.

In this talk, how urbanization and global climate change can modify the regional climate will first be presented using examples from the Pearl River Delta of China (including Hong Kong) and other mega-cities. The possible impacts of such climate hazards will then be discussed. Examples of actions taken by governments to reduce the consequences of such impacts will be presented.

English / Cantonese Prof. Johnny CHAN

What Controls the Formation and Movement of Tropical Cyclones?

Tropical cyclones, a global name of typhoons, are one of the most destructive natural disasters on Earth. Every year, around 85 tropical cyclones are formed in the tropical ocean, and they move to higher latitudes. Among them, more than 30% of tropical cyclones are formed in the western Pacific. In this talk, you will learn what controls the formation, movement, and destructiveness of tropical cyclones.

English Dr. Jung-Eun CHU

What is in Your Cell Phone Battery?

Battery is a common device that is found in all mobile electronics such as cell phone, iPads and laptops. It is often regarded as a "black box" that allows us to play games, surf the web, WhatsApp your friends, etc. Most people nowadays develop a very emotional attachment to it – anxiety rises when the battery power is low. Connection to the outside world seems to stop when the battery is dead. In this talk, we will look inside the black box to see how electricity and energy is stored and extracted. We will describe the science inside a battery, and the technological and manufacturing developments that enable mass production of the batteries. Why do we have to charge our cell phone so often? We will answer this question from the perspectives of energy supply, energy demand and user behaviours.


Dr. Denis YU

*For more information of the speakers, please refer to