G: So what are the development prospects
for the energy we use in Hong Kong?
Poon:
For energy development, we need to
take a supply and demand perspective and
view these aspects separately. On supply
side, Hong Kong currently still have some,
by present day standard, inefficient power-
generation units, with gas turbines power
plants operating at about 45% efficiency,
whereas modern technology and new
generators can work at 60% efficiency
or more. In addition to that, regarding
transmission and distribution, there are
now power transmission and distribution
transformers of higher efficiency, which are
designed to minimise the loss of electricity.
If we could construct our new power
plants and properly redesign our power
transmission network, combined with the
use of the latest technologies, we could
increase the efficiency by 15%.
Secondly, on demand side, I’ve already
men t i oned how l i gh t i ng and o t he r
equipment can improve efficiency. Lots of
power consumption actually comes from
electric motors. At present, motors are
generally at 92-93% efficient, but high-
performance motors can work at up to 97-
98% efficiency. Electric motors are used in
a wide range of applications, and so there
would be many opportunities to improve
efficiency.
Let’s also consider air-conditioning systems:
due to Hong Kong’s humid weather, people
require lower temperature conditioned
air to feel comfortable. However, there are
dehumidifiers that can reduce the humidity
of fresh air supply, thus reducing the need
for air conditioning capacity to give same
feeling of comfort.
G: We have discussed a variety of energy-
saving technologies. Do you anticipate
resistance in their implementation?
Poon:
Cost is one of the issues, as the
payback period for the implementation
of many of these technologies is long. Of
course, this depends on the prevailing
economic environment and incentives
offered. If we follow the Building Energy
Codes launched by the Electrical and
Mechanical Services Department, and if we
plan for environmental sustainability at the
very earliest stages of the project, the cost
should not be particularly high, and the
payback period can be shortened.
On the other hand, for some of the projects
in Hong Kong, the safety factor is often set
too high. For example, if a building may
require 1,000 tonnes of air-conditioning;
however, to play it safe, the engineers
may use 1,200 tonnes of air-conditioning
instead. The capacity of the air-conditioning
system will then be larger than necessary.
Unfortunately, when air-conditioning
systems are not used at its optimum design
conditions, their output efficiency would
become lower.
If we plan for
environmental sustainability
at the very earliest stages of
the project, the cost should
not be particularly high, and
the payback period can be
shortened.
The research for “Hong Kong 3030” indicates
that reductions in energy consumption must
not only come from the use of innovative
new technologies, but also from people
making changes to their everyday habits.
In fact, Ir Dr Poon believes developing good
habits is sometimes more important than
technology. His company occupies two
floors, and he encourages his employees to
use the staircase rather than the elevator.
He considers “housekeeping” to be very
important, by which he means personal
habits such as turning off lights, turning
off unused air conditioners, and so forth.
These small changes in daily habits can
actually make a big contribution to energy
conservation. Thus, while many of us may
be fascinated by the development of new
energy-saving technologies, we must also
remind ourselves to pay attention to the
things we do each day and make a personal
effort to meet carbon-emission reduction
targets.
24
GreenMAG
Feature
Interview:
Energy
