You are unlikely to think of them every time you flick that switch, but electrical engineers are at the forefront of efforts to ensure our energy supplies are sourced cleanly and used efficiently.
Janice Lee Shung-wah is an electrical engineer who works with Lloyd's Register Rail (Asia), the specialist team of transportation consultants within the London-based Lloyd's Register Group.
"Electricity is involved in all infrastructure work, including buildings, roads and railway lines," she says. "Electrical engineers are in charge of the design, planning, implementation, maintenance and testing of the system."
Energy companies also employ electrical engineers to operate and maintain power supply. In terms of product development, with the growing market for electric cars,
energy-saving lighting systems and other `green' products, demand for electrical engineers has also increased.
"Fresh graduates with a bachelor's degree in electrical engineering will be employed as a trainee engineer or assistant engineer," says Professor Norbert Cheung Chow, associate professor from the department of electrical engineering at Polytechnic University (PolyU).
"In the first two years, a great deal of their work is technical-related. In the third year, they will be assigned some supervisory duties. After three years they will be eligible to apply to be chartered."
The Hong Kong Institution of Engineers is one of the most popular bodies for chartered membership. The qualification it awards is recognised in many Western countries.
To be chartered, engineers have to submit a track record of their work, complete a written test and attend a panel interview to demonstrate their professional knowledge.
The next step is promotion to chief technical officer to perform a largely managerial function. This position requires at least eight years of experience.
Electrical engineers are in great demand in Hong Kong.
"Fresh graduates on average make around HK$12,000. Chartered engineers generally make more than HK$30,000. Chief technical officers are able to make more than HK$100,000 a month," Cheung says.
Both PolyU and Hong Kong University offer programmes in electrical engineering.
Logical thought needed
Must be able to think logically and be good in mathematics and physics
Be a team player, as most of the work involves co-operation with others
Capable of a global vision, as their work relates to crucial public policy