This seminar contains two topics as shown below:-
1. Low-Cost High Performance Daytime Passive Radiative Cooling Technology with Zero Energy Input for Mitigating the Climate Change
2. Data-driven Decision Making for Waste Management and Rouse Efficiency: Path to a Circular Economy
Programme Highlights
The Green Innovation Webinar Series aims to enhance
the collaboration between HKIE Environmental Division and universities through
exchanging new environmental technologies and novel research projects ideas via
the interactive online platform. This is the first series consisting of 2 talks
to be delivered by the professors from School of Energy and Environment of City
University of Hong Kong.
For the first talk, buildings consume large amounts of
resources and have a major impact, affecting the environment and sustainability
of modern society. The demand for cooling systems in cities has increased over
recent decades, both in commercial and residential areas. As air cooling
systems are so prevalent, the energy consumed by air conditioning systems has
become one of the largest proportions of worldwide energy usage. There are
various techniques for space conditioning. Among the various innovative
options, passive radiative coolers are more attractive since they are
environmentally friendly (refrigerant-free), with zero-energy consumption, no
vibration and quiet in operation. By using special properties of materials to
selectively reflect and emit photons in different wavelength regimes, net
cooling can be achieved if the emission of infrared energy to outer space
(where the radiation background temperature is 2.7 K) exceeds the absorption of
sunlight and other environmental thermal radiation. In this talk, we will
present different types of daytime passive radiative coolers. First, a
multi-layer photonic daytime passive radiative cooler enclosed by a vacuum system
together with a sun shade has been shown to reduce the ambient temperature by
almost 10 °C under direct sunlight in Hong Kong’s hot and humid climate. Second,
followed by the multi-layer photonic daytime passive radiative cooler, another daytime
passive radiative cooler has also been developed and tested using TiO2. Third,
inspired by the Saharan silver ants, a biomimetic polymer-based daytime passive
radiative cooler has also been designed, fabricated and tested. A numerical
analysis to estimate net cooling power has been conducted based on the measured
optical properties, resulting 144 W/m2 during the daytime. Most importantly, an
ambient air temperature reduction of 6.2 °C is achieved experimentally in a
non-vacuum enclosure during the peak daytime in Hong Kong. Fourth, we have also
developed a mathematical model to determine the indoor ambient air temperature
reduction inside an apartment by incorporating passive radiative coolers with
HVAC systems. The simulation results show that a 100 m2 passive radiative
cooler covered on the rooftop of a building can reduce the indoor ambient air
temperature by about 3 oC ideally when 5 people reside in the room,
saving 10-15% electricity consumption of a traditional air-conditioning system.
Experimentally, we have also built a small scale model house equipped with the
daytime passive radiative cooler. An indoor air temperature reduction of about
2 oC inside the model house has been achieved during the daytime
under direct sunlight. Recently, we have also developed a large scale daytime
passive radiative cooler and its field investigation is conducting in progress.
Last, other potential applications of using the daytime passive radiative
cooling technology, such as textiles, has also been discussed in this presentation.
Overall, through this talk, we aim to promote the daytime passive radiative
cooling technology to the industries in Hong Kong. We believe that our
developed daytime passive radiative coolers can inspire future architectural
and engineering design to reach net-zero energy buildings, contributing to a
cleaner environment for Hong Kong.
For the second talk, in the 2017 Policy Address, the
Hong Kong Government committed to combat climate change by reducing carbon
emission up to 70% by 2030. The adoption of a circular economy over a
traditional linear economy is one of the key routes to achieve a low carbon
future that can mitigate Hong Kong’s waste management crisis as well. Despite
the inherent benefits of the circular economy, its adoption is low due to the
lack of data and tools for improving resource efficiency and waste management.
In this talk, Dr. Shauhrat Chopra will highlight the utility of tools such as
Life Cycle Assessment (LCA). In addition to well-established tools like LCA for
data-driven decision making, the talk will also showcase the opportunity for
the development of novel Information and Communication Technologies (ICT)
tools. In particular, blockchain enabled data-driven tools may have the
capability to improve trust and transparency in supply-chain networks,
platforms for shared and performance economy, stakeholder participation, and
governance and management of organizations. For this reason, Dr Chopra will
share the potential opportunities and limitations of the blockchain technology for
circular economy applications. Finally, the talk will emphasize the
significance of data-driven tools and systems analytics to avoid unintended
negative consequences of engineering decisions on the environment.
Speakers
The first talk will be presented by Dr Edwin Tso,
Assistant Professor, School of Energy and Environment, City University of Hong
Kong. He received his Bachelor’s degree in Mechanical Engineering (First Class),
MPhil degree in Environmental Engineering and PhD degree in Mechanical Engineering
from The Hong Kong University of Science and Technology (HKUST) in 2010, 2012
and 2015, respectively. He was awarded the Fulbright – Research Grant Council
(RGC) Hong Kong Research Fellowship in 2014, and studied at the University of
California, Berkeley (UC Berkeley) in 2015. After he came back from the UC
Berkeley, he was a Research Associate at the Department of Mechanical and
Aerospace Engineering (MAE), HKUST from 2015-2016, and promoted to the rank of
Research Assistant Professor (2016-2018) before he joined CityU in Sep of 2018.
He was also a Junior Fellow at the HKUST Jockey Club Institute for Advanced
Study from 2016-2018 when he was at HKUST. Dr. Tso’s research interest covers
thermofluid, heat transfer, energy and built environment, and energy efficient
building technology, particularly, in the fields of adsorption technology,
thermal diodes/switches, nanofluids/hybrid nanofluids, thermochromic smart
windows and passive radiative cooling using numerical simulations as well as advanced
experimental techniques. Dr. Tso has published about 40 journal papers and 22
conference papers. He is also active in entrepreneurship and technology
transfer, and has obtained several patents and has been involved in setting up
a start-up in late 2012.
The second talk will be presented by Dr Shauhrat S
Chopra, Assistant Professor, School of Energy and Environment, City University
of Hong Kong. He obtained his Integrated Masters of Science in Systems Biology
from the University of Hyderabad, India in 2011. He received his PhD in Civil
and Environmental Engineering from the Swanson School of Engineering at the
University of Pittsburgh, USA, in 2015. His doctoral dissertation was focused
on resilience of complex systems including economic systems, industrial symbiosis,
and critical infrastructure systems at urban and national levels. Before
joining the School of Energy and Environment, Shauhrat worked as a Postdoctoral
Researcher at the Institute for Environmental Science and Policy, University of
Illinois at Chicago, on the U.S. EPA funded LCnano project focused on
sustainable design of future transformative nano-enabled products. His
data-driven research is focused on designing indicators for sustainability and
resilience of the built environment in support of environmental
decision-making.
Language
English
Registration & Enquiries
The seminar is free of charge with maximum of
participants of 100. For registration, please complete the online Google Form.
Successful applicants will be notified before the event. For enquiries,
please contact Mr. Benjamin Lam at bencamay1119@gmail.com . Attendance certificate will be
awarded after seminar.