Electricity

Electricity
Operating Railway MTR is one of the most energy efficient mass transport systems in the world and considerably more efficient than motorised road vehicles. However, transporting 2.2 million people every day necessitates the consumption of large quantities of electricity. As a major cost and important environmental issue, MTR proactively manages electricity consumption whilst maintaining the highest safety, service and comfort levels for passengers. Over 2001, energy consumption for the operating railway decreased by 0.06% to 709,170MWh. This modest reduction was achieved in the context of enhancing urban line passenger services by reducing the time between trains from 5 minutes to 4 minutes between 0930-1630hrs on weekdays and 1000-2000hrs on Sundays. The additional traction energy required was offset by a number of initiatives identified and implemented by the Energy Management Working Group including:
	Smoother train regulation between stations.
	Reduced energy consumption at stations through measures such as switching off certain escalators during non-peak hours.
	Reduced energy consumption at depots through measures such as switching off lighting when they are not needed.
	Reduced consumption at Headquarters through measures such as reducing the operation hours of Air Handling Units after office hours.
The following figure illustrates MTR's traction energy per car-kilometre over the last ten years. Traction energy decreased in the early 1990s when regenerative braking (which converts forward motion into energy to be used later for acceleration) was introduced but has increased slightly year on year since 1995 as increased train frequency has required more demanding regulation between stations. Over the next 3 years, MTR intends to fit its urban line trains with static invertors. These convert electrical power into traction power more effectively and the fitting of the invertors will also help further reduce noise from operating trains. Another initiative is the ongoing programme to fit platform screen doors. By sealing off the tunnels from the platform and station, the space to be cooled by the air conditioning system is considerably reduced with corresponding energy savings. Over the next five years, 2,920 sets of platform screen doors will be fitted. Property Property Development is currently incorporating a number of energy efficient features into the design of new buildings including:
	Optimisation of Overall Thermal Transfer Value.
	Specification of Variable Air Volume and seawater cooled air conditioning - the latter being 30% more efficient than air cooled systems.
	Specification of electronic (rather than electromagnetic) ballasts in lighting systems.
In 2001, Property Management replaced almost 5,000 tungsten filament bulbs with compact fluorescent tubes at the Tierra Verde, Tung Chung Crescent, Waterfront and Island Harbourview developments. It is expected that this initiative will result in savings of 1,000MWh energy and almost HK$900,000 per annum.