Powering our communities

We generate and deliver electricity safely and reliably, at a competitive price and with the least environmental impact, to power the development of sustainable communities. 
Most Material Topic : Availability and Reliability
Most Material Topic : Demand-side Management

Availability and reliability

Availability and reliability are two key performance metrics for CLP assets. For our generation assets, we monitor the “Equivalent Availability Factor”, which typically ranges from 70-90% and is a key performance measure for each of our assets.

In Hong Kong, we maintain a world-class supply reliability of over 99.999%. Between 2015 and 2017, on average a CLP customer experienced 1.57 minutes of unplanned power interruptions per year. This is higher than the 1.48 minutes between 2014 and 2016, due to the impact of severe strong Typhoon Hato on 23 August 2017, without which we would have seen a significant reduction.

This achievement shows the value of factors such as a stable and supportive regulatory framework that encourages careful investment planning, as well as the professional expertise of our staff in power operations.

In 2017, we continued to enhance the reliability and security of our supply system and invested HK$8.1 billion to maintain and enhance our supply system and generation assets to meet both current and future energy demand. We commissioned two new 132kV substations to provide power supplies to a data centre in Tseung Kwan O and the new border control facilities at Heung Yuen Wai.

Find out how we monitor availability and reliability of cur assets

Most Material Topic : Energy
Material Topic : System Efficiency

Power generation

Since our first 75kW generator was commissioned over a century ago in Hong Kong, we have increased our generation capacity in operation and under construction across the Asia Pacific region to 19,395MW of equity generating capacity, supplemented with an additional 5,159MW of capacity purchase. Our generation portfolio utilises diverse types of energy sources, including coal, gas, nuclear and renewable energy (wind, hydro and solar).

In 2017, the Group’s total electricity sent out on an equity plus capacity purchase basis increased to 83,897 GWh from 79,583GWh in 2016. Our total generation capacity increased from 18,622MW in 2016 to 19,395MW on an equity basis (23,781MW to 24,554MW on an equity plus capacity purchase basis), due mainly to our 17% investment in Yangjiang Nuclear Power Co Ltd (gaining 1,108MW of nuclear capacity). Coal capacity remained similar, while our non-carbon equity generating capacity increased from 3,582 MW to 4,350 MW, again due mainly to increased investment in nuclear capacity. However, divestment of our minority shares in some wind assets in Mainland China contributed to a dip of our renewable equity generating capacity from 3,090MW to 2,751MW.

We are committed to continue growing our non-carbon emitting portfolio and as mentioned earlier, we have set an additional renewable energy target of 30% and a non-carbon emitting target of 40% by 2030, as part of our Climate Vision 2050 review in 2017. We will begin to consistently report also on our generating capacity on an equity plus capacity purchase basis starting next year.

We report the annual operating performance of our generation portfolio for those assets which fall within our environmental scope (as defined in the Reporting Scope section). The performance metrics include the availability factor, generation sent-out, thermal efficiency and energy intensity.  

Download the generation performance of our assets in 2017

Material Topic : System Efficiency

Transmission and distribution

While CLP has generation businesses across the Asia-Pacific region, Hong Kong is the only location where we operate a transmission and distribution network. This serves about 80% of the population of the city and close to 100% of the population in our service area.

The reliability of our system is above 99.999%, higher than other major international cities such as London, New York and Sydney. At the end of 2017, we had approximately 1,164 km of overhead and approximately 14,514km of underground circuits at medium or higher voltage. In addition, we also had 232 primary and 14,483 secondary substations in Hong Kong.

In 2017, our average network loss for the past five years was 4.04%, slightly lower than our 2016 figure of 4.1%.

We use a set of universally recognised supply reliability performance indicators from the IEEE 1366-2012 standard to monitor our system performance. These indicators are the core attributes for power systems and are reported annually to the Hong Kong Government.


Supply Reliability Performance Indicators

System Average Interruption Frequency Index (SAIFI)

The average number of supply interruptions for each customer served. Both planned and unplanned interruptions are included.

  • Our three-year average SAIFI (2015 – 2017) was 0.18, meaning our customers experienced a power interruption approximately once in five years during this period.
  • It remained the same as last year’s three-year rolling average.


System Average Interruption Duration Index (SAIDI)

The average duration of interruptions each customer may encounter in a given year.


  • Our three-year average SAIDI (2015 – 2017) was 0.34 hours including both planned and unplanned interruptions.
  • This is an improvement over last year’s three-year average SAIDI (2014 – 2016) of 0.35 hours.


Unplanned Customer Minutes Lost (Unplanned CML)

The average duration of unplanned power interruptions per customer in a given year. These outages occur without prior notice, and happen as a result of various factors such as weather events, third party damage to the network and equipment faults.

  • Our three-year average (2015-2017) unplanned CML was 1.57 minutes, which is higher than 1.48 minutes between 2014 and 2016.
  • The increase was mainly due to severe Typhoon Hato on 23 August, without which we would have seen a significant reduction.

Investing in a climate resilient grid

2017 was one of the hottest years on record and we saw many high-impact extreme weather events including hurricanes, floods, heatwaves and drought. Such events can often cause disruptions to power supplies. Therefore, it is critical that our assets are resilient enough to withstand these extreme conditions to minimise disruptions to electricity supplies for critical services and infrastructure, and to enable faster recovery of affected communities. In 2017, Hong Kong experienced seven tropical cyclones, of which one was Typhoon Hato bringing in wind speeds of up to 185 km/h. Due to the strength and resilience of our power system, there were no systemic power failures, in contrast to the neighbouring city of Macau, which completely lost all electricity supplies to over 250,000 customers.

Overhead lines make up a significant part of CLP’s Hong Kong transmission and distribution network, where more than 700 pylons of 400kV overhead lines form the backbone of the supply system. If a pylon is destroyed by strong winds or collapses because of a landslip, it can take several months to restore to order. Over the years, we have been reinforcing the pylons of 400kV overhead lines so the structures can withstand such super typhoons. CLP conducts regular emergency typhoon drills, particularly ahead of Hong Kong’s typhoon season to help reduce the vulnerability of the power system and minimise the down time required for recovery from extreme weather events. Emergency restoration systems were introduced to construct the temporary pylons quickly so as to reduce the recovery time. We have also implemented additional measures to counter the potential impact of severe typhoons and storm surges. These include installing smart switchgears on distribution overhead lines, installing flooding prevention measures and alarm systems at low-lying flood prone substations, and establishing a typhoon response protocol and coordinating system.

Moving towards clean energy

In 2017, we made progress towards our target of 30% non-carbon emitting capacity by 2020, as our non-carbon equity generating capacity increased from 19.2% to 22.4%, due mainly to our increased investment in nuclear capacity. However, progress on our 20% renewable energy capacity by 2020 was slightly hindered by our divestment of wind assets in Mainland China combined with our increased nuclear capacity, both contributing to a fall of the share of our renewable equity generating capacity from 16.6% to 14.2%. Fluctuations are expected from year to year, but pursuing an overall trend of increase is the key objective.

We are working diligently to meet our upcoming targets of 20% renewable and 30% non-carbon generating capacity by 2020. These interim targets are part of our journey towards the new Climate Vision 2050 review targets of 30% renewable and 40% non-carbon energy capacity by 2030, which will require even more expansion of CLP’s non-carbon energy presence over the coming years.

A new Group-level Renewable Energy team was set up in 2017 to support regional teams to meet our ambitious climate and investment targets. This team is working with regional teams to grow our renewable energy presence and pipeline, achieve operational excellence across all of our renewable assets and explore the potential to expand into new markets and technologies.

While developers, including CLP, have often relied on external service providers to provide operations and maintenance services at sites, CLP has begun to internalise this capability at many sites in India and China, increasing the level of renewable energy operational expertise within the organisation, to add to our extensive expertise in project development and construction.

We will continue to expand our presence in established renewable energy technologies such as onshore wind and solar, with several opportunities to construct new sites or acquire operational assets currently being considered.



2017 Clean Energy Development

Hong Kong
  • Continued connecting renewable projects to our grid. At the end of 2017, we had about 300 renewable energy systems with a capacity of about 41MW connected to our grid;
  • CLP continues to play a direct role in the development of Hong Kong’s renewable energy resources by connecting the government’s large-scale waste-to-energy projects to our grid. We are also exploring our own utility-scale renewable energy opportunities, for example, by pioneering Hong Kong’s largest landfill gas power generation project at the West New Territories (WENT) Landfill site that will produce 10MW of renewable power. The amount of energy produced will be enough to meet the annual electricity demand of around 17,000 four-person homes. We expect it to be operational in 2018.
Mainland China
  • Our clean energy portfolio in Mainland China was strengthened by the acquisition of 17% interest in Yangjiang Nuclear (1,108 equity MW) in December 2017. The station comprises six 1,086MW generating units, of which four units are in commercial operation and the other two units are currently under construction with targeted commissioning in 2018 and 2019 respectively.
  • Meanwhile, we continued to have a strong renewables portfolio in Mainland China. 62MW of renewable energy projects were commissioned in 2017, including Laiwu II Wind (49.5 equity MW) wind and Huai’an Solar (13 equity MW).
  • With our maiden 100MW Veltoor Solar Farm in Telangana in southern India, the size of our commissioned renewable portfolio in India has been taken to 970MW. CLP currently owns 49% of Veltoor and we have an option to acquire the remaining 51% in future from our partner Suzlon.
  • EnergyAustralia has entered into transactions to underpin the development of more than 500MW of renewable generation capacity since we announced in December 2016 a programme to support new wind and solar farms in eastern Australia. Together with existing commitments, these power purchase agreements (PPAs) will help EnergyAustralia meet our obligations under the Australian Government’s Renewable Energy Target, which requires retailers in the NEM to source approximately 23.5% of electricity sales from renewable sources by 2020.

Energy Recovery at EnergyAustralia

At Mount Piper Power Station, we announced plans to assess the viability of converting part of station to run on non-recyclable materials, an Australian first. The proposed A$160M energy recovery project will allow Mount Piper to produce more energy for the same amount of coal. The feasibility study showed it was possible to generate around 27MW of electricity, enough to power around 40,000 homes. A decision whether to proceed with the project will be taken in 2019, with first power scheduled for 2021.

New markets and technologies for renewable energy

Renewable energy is a relatively new field in comparison to traditional thermal generation and it continues to undergo rapid changes. CLP is closely monitoring these changes and we are conducting research into emerging technologies and markets in order to remain at the forefront of technological innovation and market developments.

Among the technologies under investigation are offshore wind, which is now being embraced by governments across the region, and floating solar. CLP has been working for the Water Services Department to construct floating solar plants at Shek Pik and Plover Cove reservoirs in Hong Kong. Both offshore wind and floating solar may offer potential for strong growth across Asia Pacific in future years, particularly due to land constraints which increasingly hinder new land-based projects.

As renewable energy expands its presence, energy storage solutions will also need to be considered. In recognition of this, CLP is actively developing storage opportunities, including battery storage projects in Australia and pumped hydro storage.

Energy Storage at EnergyAustralia

EnergyAustralia is assessing projects which may play leading roles in a new, modern energy system in Australia. Our proposed 225MW seawater pumped hydro project in South Australia is one example. During the year it passed a major milestone with initial feasibility work indicating no major barriers to development. The project, which would store energy like a battery for times when it is needed, is attractive for its ability to support the integration of intermittent renewable supply into the grid in a way that delivers affordable, reliable and cleaner power for customers.