Improving the Energy Efficiency of your Data Centre

As a responsible electricity provider and a collaborative energy management partner, CLP promotes best practices in Energy Efficiency and is committed to delivering value to the data centre industry in Hong Kong.

Best Practices for Energy Efficiency in Data Centres
KPI of EnergyNet (DCIM solution)
CRAC unit with free cooling
Adjust intake air temperature
Inside cold aisle containment


We can’t manage what we don’t measure: conduct regular energy audits and have energy usage record could help pinpoint areas for improvement quickly and have a base reference for post implementation measurement.

HVAC Improvement

  • Installation of dust free direct cooling system: When the ambient environment is favourable, a dust free direct cooling system brings outside ambient air to cool down the IT equipment and exhaust the hot air from IT equipment out of the data centre. This reduces the energy consumption of chiller system
  • Use of centralised cooling system: Typically, a centralised cooling plant has higher Coefficient of Performance (COP) and is more efficient than unitary air-conditioning system
  • Consideration of fine water mist system for air-cooled chiller: By injecting water mist towards the condensing coils on the air-cooled chillers, the heat rejection performance and the energy efficiency of the air-cooled chillers can be enhanced significantly

Environmental and Airflow Management

  • Adjust the intake air temperature: Adjusting the intake air temperature close to the highest acceptable value of IT equipment is one of the effective ways to improve energy efficiency
  • Eliminate humidification and dehumidification: Energy efficiency can be improved by employing a wider operational humidity range without affecting the IT equipment operation. Consideration of disabling humidity control can be further reviewed
  • Installation of hot/cold aisle containment: In additional to the hot and cold aisles arrangement, containment system can be used for further improving the energy efficiency by separating the cold air supply and hot exhaust air
  • Use of variable speed fan: Variable speed fans together with temperature sensors can be used to deliver just enough cooling matching the IT equipment needs
  • Use of blanking plate: The unused space in a cabinet should be covered by blanking plates to prevent short-circuit of air between hot and cold aisles
  • Use of smart lighting system

Space Management

  • High power density: High power density rack can reduce the footprints required by IT equipment and effectively cool the IT equipment inside a cabinet
  • Zoning: Partition portion of the data centre as high power density zones and group similar power density equipment into a zone that matches the actual cooling requirement and capacity

IT Opportunities

  • Enable power management feature
  • Consolidation of lightly utilized servers by virtualisation

Other Opportunities

  • Rightsizing design
  • Selection of energy efficient equipment
CLP Energy Benchmarking Service

CLP Launched Energy Benchmarking Service at its First Data Centre Symposium

On 25 September 2013, CLP unveiled an Energy Benchmarking Service designed specifically for the Hong Kong Data Centre industry at its first Data Centre Symposium. The benchmarking service is part of CLP's efforts to promote energy efficiency in the business sector, enables data centre operators to better understand their energy consumption relative to their industry peers as well as share and access local and overseas best practices.

Hong Kong government officials including Mr Daniel Lai, BBS, JP, Government Chief Information Officer and the Honourable Charles Mok, Legislative Councillor (Information Technology) conducted the presentation in the symposium along with industry experts such as Forrester Research, data centre operators including NTT Com Asia and Global Switch. Attendees included over 200 industry professionals who face the challenges of operating green and sustainable data centres.

At the symposium, CLP shared the initial results of its energy benchmarking service, which was well received by the interested audience.

The Energy Benchmarking Service provides participants with:

  • An understanding of their energy performance relative to their peers, including their Power Usage Effectiveness (PUE) against their peers in various dimensions such as trade, size and grade
  • Insights into best practices deployed in Hong Kong and overseas
  • A customised report that could help Data Centre implement initiatives to save energy and costs

Click here for the details of Energy Benchmarking Service

If you run a data centre, you are welcome to register for the Energy Benchmarking Service. Please contact your Account Manager or email

Details of the topics presented:
  1. CLP: Energy Benchmarking Service for DC Industry in HK and Initial Findings, click here
  2. CLP: Energy Efficiency Case Study: CLP’s Internal Primary Data Centre, click here
  3. Forrester Research: Global Green Data Center Best Practices In Action, click here
  4. Global Switch: Towards LEED Platinum Certification – Global Switch Hong Kong Data Centre Design, click here
  5. NTT Com Asia Limited: Application of Green Technology for Data Centre, click here

Sustainability Report

Every year CLP publishes an update on its sustainability practices for different geographies. Click here to read the latest report online, or to download the PDF.