Lanka Electricity Company is gearing up Sri Lanka’s clean energy target

The Government of Sri Lanka has set an ambitious target to generate 70% of electricity through clean energy sources by 2030. CEB is planning to integrate additional 2,338 MW of solar power and 765 MW of wind power to the national grid to achieve this target by 2030. With time, CEB and LECO have taken many initiatives in promoting research and development in the country in collaboration with the universities to fill this gap. Within this context, CEB has taken several initiatives under the overall policy advice from the Government to promote solar and wind power projects. Thus, private sector participation has improved significantly over the past few years, in mobilising substantial amount of financial resources from the market and carrying out efficient project implementation works

By Dr. Narendra De Silva and Eng. Keshan Samarasinghe

If you are interested in energy sector activities and a good reader, you may have already understood that solar and wind energy can play a major role in Sri Lanka to achieve its goal in low carbon electricity generation and secure low-cost electricity to supply the consumers in the country.

Future renewable energy performance in Sri Lanka 

With the collective effort specially Ceylon Electricity Board (CEB), Lanka Electricity Company (LECO), Public Utility Commission (PUCSL), and Sustainable Energy Authority (SLSEA), Sri Lanka has already installed 32,411 rooftop solar systems with the total capacity of 367 MW as of April 2021. In addition, 33 MWs of ground mounted solar PV plants and the largest wind farm, a 100 MW facility in Mannar are already connected to the national grid. 

The Government of Sri Lanka has set an ambitious target to generate 70% of electricity through clean energy sources by 2030. CEB is planning to integrate additional 2,338 MW of solar power and 765 MW of wind power to the national grid to achieve this target by 2030. With time, CEB and LECO have taken many initiatives in promoting research and development in the country in collaboration with the universities to fill this gap. 

Within this context, CEB has taken several initiatives under the overall policy advice from the Government to promote solar and wind power projects. Thus, private sector participation has improved significantly over the past few years, in mobilising substantial amount of financial resources from the market and carrying out efficient project implementation works. 

Why is this moving slowly? 

Within this context, CEB as the major electricity utility in the country has taken enormous effort during recent times to increase the share of renewable energy in the power system. It is no secret that the absorption of renewables into a power system poses multitude of challenges due to renewables are intermittent and variable. The power system has a flexibility at the moment, but it is gradually becoming tighter with more and more renewable coming into the system. Therefore, admission of renewables in large quantities to such designed power system needs to be done with substantial augmentations. By the time, the technology is matured and the commercially available to mitigate most of the challenges which the renewables pose into the electricity grid. 

Anyhow one could understand that introducing a new technology into the system is challenging in the initial phase and any modernisation is directly coupled with additional cost. Once a technology passes this maturity phase, then its deployment can be incorporated into the planning and development lifecycle of a country. Until such time, it is not unreasonable that the planners do not incorporate such technologies into their plan.

The maturity phase of any technology is taken care not by the users of such technology but by another system which we call research and development centred around science and technology sector in any country. Unfortunately, within our country we do not have such a matured research and development sector focused on power and energy related research in taking care of this issue. It needs to be commented here that the recent research and development centred around the engineering faculties in the country is rapidly maturing into the most expected Power Research Institute which now requires Government intervention to formally established and also strengthen NERD (the National Engineering Research and Development Centre).

Unexpected power interruptions, who pays for it?

The cost of electricity interruption and economic impact always depends on customers’ utilisation and his/her reliance on electricity. The cost can be divided in to two parts, Direct Costs: covering immediate losses that arise because of an interruption and Indirect Costs: covering the subsequent impact to the overall economy due to the unserved energy which even though no payment is made, but apparent as a loss of opportunity in the economic context. Therefore, both calculation as well as the compensation for such losses are difficult. 

In a study carried out in 2002, it was estimated that the costs of unserved energy in the Sri Lankan industrial sector is in the range of $ 0.66 per kWh for planned interruptions which the customer has received prior notice and $ 1.06 per kWh for unplanned interruptions. These values have substantially increased with the economic development during the last two decades. In 2016, another study estimated that the costs of unserved energy in the apparel industry (textile and leather) and chemical industry (petroleum, rubber, plastic) are in the rage of $ 2 per kWh and $ 3.30 per kWh respectively. 

The overall system failures, which are the worst form of outage any power system can suffer, are also becoming prominent in the Sri Lankan system. The recent most two system failures we suffered in August 2020 and March 2016 may not be seen as isolated event but as a tip of an iceberg which is emerging from the still waters. Especially in the event we suffered in August 2020, power was restored in the capital only after about seven hours. It was even longer in several other parts of the country. 

The restoration process experienced a novel phenomenon where the system retaliated back to cascaded system failures once the Colombo suburb loads are energised. Some believe that the grid restoration process was a challenge in Colombo city and suburb area than earlier experiences because of the large number of small-distributed rooftop solar systems. This was triggered by the resynchronising impact of the solar inverters at the onset of the grid. It is much earlier to establish such as a conclusion without detailed power system stability studies but not a hypothesis the engineering community should ignore.

It is imperative that the engineers while in one hand embrace renewable energy as the future source of energy in taking part of the mission of greening the grid and nationalising the grid, shall vibrantly research into the solutions to the grid stability and supply quality issues related to renewable admission. The incidents within our soil as well as the international experience show rapid development and implementation of intermittent renewable power-based electricity generation results in greater challenges to the operation, control, and security of the national grid. 

Minimum thermal power but almost 100% reliability, is it possible? 

CEB and LECO together look after the entire electricity distribution system in the country. These institutions are committed to providing efficient service and highest possible reliable power supply to their consumers. Therefore, regular maintenances on the low, medium, and high voltage networks around the country are carried out in respective area. As a result of these planned power interruptions coupled with unplanned power failures due to events beyond the control of the utilities such as bad weather incidents, vehicle accidents, and animal activities, the electricity consumers find difficulties in maintaining their activities. 

With the rapid development of renewable energy market, flexibility of grid is becoming increasingly important to absorb more and more intermittent renewable energy into the system. Most of the developed power systems now separately recognise those parties providing such flexibility in the national grids. Also, utility regulators are now creating an enabling environment to form such flexibility in the power system that will support boosting the renewable energy development in a country. 

Microgrid is an innovative technological intervention paving the way for clean energy transition with almost 100% reliable power supply. A microgrid refer to a grid-connected setup which can be operated with or without the national grid. Most of the microgrids are set up where reliability of supply is paramount like some cities with critical economic activities, hospitals, universities, military bases, IT companies, and other commercial and essential service areas. 

Can your rooftop solar systems generate electricity during power outages in the grid? 

Once of the key aspects of a microgrid is that the consumers can have uninterrupted power supply during a power failure in the main grid. Even a consumer doesn’t feel the power outage in the national grid as the microgrid system has potential for a seamless transition between on-grid mode (operate synchronously with the national power grid) and off-grid/island mode (operate independently of the national power grid). 

Also, the integrated renewable energy sources such as solar and wind in the microgrid system can generate electricity during a power outage in the national grid. A microgrid has an ability to maintain the balance between available power supply and desirable load demand via integrated smart control units. The main components of a microgrid are shown in Figure 1. 

Microgrids are better than standalone solar and wind power plants 

Microgrid can produce and efficiently manage internal power generation, storage resources, and power consumption throughout the year to have reliable power supply as well as least cost power generation. Microgrids can strengthen the effort of the Government and electricity consumers in promoting renewable energy-based power generation and maximising renewable energy consumption in the county. It helps the power sector to move towards a smooth low carbon energy sector transition and reduce greenhouse gas emissions from power generation. In addition to that this will helps utility to minimise power purchase from high-cost fossil power plants. 

Microgrid supports in reducing financial and economic loss resulting from unserved electricity during power outage. Also, microgrid reduces transmission and distribution network losses because electricity generation in a microgrid at the load centre. It helps the consumers to minimise the demand charge from the monthly electricity bill as microgrid can be operated in the peak shaving (peak electricity demand reducing) mode. The peak shaving technique manages overall demand while eliminating short-term demand spikes on utility grids. The battery storage system can proactively respond to smoothen voltage fluctuations resulting from solar PV and wind power intermittency. As a result, the utility companies can defer the investments on upgrading Transmission and Distribution (T&D) infrastructure accruing saving to the utility companies. 

LECO’s enormous 

potential to implement microgrid projects

LECO together with the University of Moratuwa has started a pioneering microgrid pilot project with a grant assistance of $ 1.8 million (approximately Rs. 360 million) from Clean Energy Financing Partnership Facility of Asian Development Bank (ADB). The pilot project contains a commercial microgrid and R&D facility which will be used as a research platform for the studies related renewable energy integration and smart grids. 

The Ministry of Power (and Energy at the time) in Sri Lanka and South Asia Energy Division of ADB had conceptualised this intervention as a part of its continuous assistance to expand clean energy development in Sri Lanka. LECO, a leader in power distribution always willing to embrace new and innovative concepts was chosen as the implementing partner to realise this concept. 

A microgrid coupled with a battery energy storage system (BESS) is one of the best technologies to minimise voltage fluctuations and maintain voltage stability of the grid. BESS supports in meeting the real time power requirement to ensure the energy balance and availability. Microgrid can store energy from renewable energy during the off-peak load period and discharge the energy during peak load period. This will help transmission and distribution network to accommodate more intermittent renewable energy and minimise curtailment of power from renewable energy. Figure 2 shows one of the best examples for an operation status of an 80 MW renewable energy plant.  

Microgrids, an important player in achieving 70% clean energy target

Imported fossil fuel-based power generation and unreliable electricity supply have a major detrimental impact on economic development in the country. LECO has identified smart microgrid concept as a total solution to the issues arising from renewable energy sources such as voltage issues, rapid frequency fluctuations, and power quality disturbances and for improving reliability as well as to minimise fossil fuel consumption. Smart microgrid would be the future building block of national grids and development of the Microgrid Laboratory in the University of Moratuwa will be the focal point of the power system development in the country. 

Sri Lanka is considered as one of the most vulnerable countries of climate change. To mitigate its vulnerability, we need to continue its transition to clean energy and adapt to climate change together with other countries in the region. It is important to enhance national and regional cooperation. The country can then secure more clean energy sources and technologies such as hydrogen and natural gas, cleaner refined petroleum products, waste to energy plants, solar, wind, and BESS. There are many challenges. 

The speed of energy sector transition always depends on the country’s level of economic development. It is possible if we can work together and collaborate with other stakeholders in the country as well as in other countries in the region to secure more affordable energy sources and technologies. 

Sri Lanka as an Upper Middle-Income country should take the lead as Sri Lanka has always done. LECO is ready to support this endeavour, take the lead, and collaborate with others to achieve the clean energy target in the country for a sustainable economic development in Sri Lanka. 

(Dr. Narendra De Silva is General Manager – Lanka Electricity Company Ltd. and Eng. Keshan Samarasinghe is Consultant – Asian Development Bank.)