Uninterrupted, Quality Power Supply: Bangladesh to Achieve Target by 2025

Saleque Sufi

Access to uninterrupted and modern power supply for all at an affordable price is the pledge of the nations of the world as per Sustainable Development Goal 7 (SDG7). Bangladesh is also a signatory of the SDGs. We are aware that despite various issues and constraints, Bangladesh appears to be on the right track to achieving its goal. Access to power for all has been achieved. Generation capacity has a reasonable surplus. However, quality power supply on an uninterruptible basis is constrained by fuel supply deficits and issues with transmission and distribution infrastructure. Power transmission and distribution utilities are implementing various capital-intensive projects to expand and upgrade the power value chain's mid and downstream segments. Sources at Power Division and BPDB said they were expecting to ensure quality power supply on an uninterruptible basis by 2025.

Fuel Mix for Affordable Power Supply

Affordable supply also depends on fuel mix and optimum utilization of its primary fuel. The global fuel market is extremely volatile for COVID impacts followed by the Ukraine War. From 2009 to 2022, Bangladesh achieved milestones one after another in power generation by introducing and encouraging private sector investment. Generation capacity has increased from about 5 gigawatts in 2009 to 25 gigawatts in 2021, and access to energy has expanded to nearly 100 percent of the population. The reliability and quality of electricity remain major issues. Improving the supply and reliability of electricity and energy in general, while maintaining affordability, is essential to supporting the continued growth of industry and commerce in Bangladesh. Sustained economic growth at an impressive 6.5% and above has expanded the demand. This facilitated Bangladesh achieving recognition of graduation from least developed country status to developing economy. The nation aspires to grow into a developed economy by 2041. The power demand is expected to grow above 50,000MW by 2041. The government requires securing investment for achieving generation covering the demand including a reasonable reserve margin. Investment is also essential in power transmission and distribution systems for ensuring quality power supply on an uninterruptible basis at an affordable cost. That is also the global vision nations of the world pledged to achieve by 2030 in the SDG. A sustainable quality power supply would help propel the growth of export-oriented industries and also meet the growing needs of citizens across the nation. The government already achieved its vision of bringing the entire population under power supply coverage.

Synopsis of Power Sector Performance over the Past Decade

Some sources estimate US$125-150 billion investment across all segments of the power value chain. All are aware that generation capacity witnessed phenomenal growth over the past decade for enabling government policy. A huge reserve margin causes generation costs to go higher. The government cannot convince industries to rely on grid power. Petrobangla supplying gas to captive power plants cannot meet the demand of grid-connected gas-based power plants. During a week and a half just past Ramadan, Petrobangla required rationing gas supply to industries to increase supply to grid-connected power plants during Ramadan. It was possible to generate 14,782MW on 16 April 2022. Even then BPDB has to rely on 3,500-4,000MW generation from liquid fuel-based power plants. However, BPDB had to account for capacity charges. As such BPDB continued to suffer from operating losses. The government either has to increase subsidies or BERC has to positively consider power tariff adjustment. For improving power transmission and distribution, BPDB has launched a major upgrade program of the power grid and modernization of distribution networks. By 2025 power supply chain is expected to improve substantially toward an uninterrupted quality power supply.

Constraints in the power transmission grid and distribution network are also the reason for Bangladesh not being able to ensure quality power supply on an uninterruptible basis. The constraints were identified in both the PSMP 2010 and PSMP 2016. But neither government could invest nor could attract private investors. Unlike generation, appropriate policy for integrating the private sector in midstream and downstream segments of the power value chain was not there. There was little or no control over the growth of demand over distribution franchises. Consumers continued using energy-inefficient appliances. The demand outpaced supply system capacity in city areas creating disruptions due to overloading at peak hours. As far as general capacity is concerned, despite a huge reserve margin some areas still experience some loadshedding. However, distribution utilities in respective areas have overcome most of the bottlenecks and the system is getting more and more reliable every passing day. The entire power system is expected to come under the SCADA system soon. Many substations have been upgraded and few added. Industrial areas as major load centers are being connected to more than one feeder. However, some major project implementations delayed PGCB for poor project management. The reason for not being able to evacuate the full capacity of Payra 1,320MW is the delay in PGCB implementing the Payra – Gopalganj - Dhaka Transmission line or contingency grid expansion to the Khulna region. However, finally, by December 2022 or early 2023, these would be resolved. The supply of power from Payra and Rampal should improve the power transmission situation remarkably. BPDB and relevant distribution utilities DPDC, DESCO claim that it is possible to serve most of the industries with reliable grid power. Moreover, industrial rooftops and access to the grid through net metering should also improve the situation significantly by 2025. 

Fuel Mix Major Constraint

Developing a 400 KvA transmission grid backbone and implementing various projects of distribution entities like burying lines underground, increasing numbers of grid substations, SCADA and GIS integration, and constructing double lines eventually would substantially increase reliability. By 2025 at least three large modern coal power plants and 2,400MW capacity nuclear power plants would relieve the power system reasonably from reliance on gas. If transmission grid upgrading is completed by that time, at least there must not be an issue with sufficient baseload generation capacity. But the fuel for large coal plants and nuclear power plants is imported. Global fuel market price of coal and transportation costs would be a factor in generation cost. The biggest worry is with natural gas. The power system still depends at least 50% on natural gas.

It is expected that under preparation integrated power and energy system master would work out a balanced fuel mix taking into account Bangladesh's inability to absorb the price risk of primary fuel from volatile global markets. Experts suggested reducing reliance as much as possible on natural gas. After years of negligence, it has become extremely difficult to increase supply from our source through exploration onshore and offshore in the foreseeable future. Another option is exploiting its coal reserve and expediting renewable energy development. Bangladesh can not rely on expensive LNG for a long time. The global situation and circumstances evidenced that Bangladesh cannot compete with aggressive buyers in Europe, China, Japan, Korea, Taiwan and India.

Major Upgrading and Modernization of Power System

PGCB is taking care of power transmission grid upgrades, DPDC, DESCO, and other distribution utilities are modernizing distribution networks. People of Dhaka megacity by 2023 may be free from all overhead power lines. Power cables are going underground. Hopefully, in a few years, Dhaka city would have Ring Main Units (RMU), Low Tension Distribution Boxes (LTDB), and KIOSK Transformers. Eventually, Bangladesh’s power supply chain would have a modern technology-driven smart grid and smart distribution network. Outbreaks of COVID impacted the implementation of some projects. Otherwise by 2022 Dhaka city distribution could start getting the benefits.

PGCB is working on options for safer and smarter control over power transmission and delivery to distribution systems managed by distribution utilities. Serbian Consultant Energoprojekt Entel PLC in association with local BCL Associates Limited presented the inception report on the integration of power transmission lines and grid substations towards the development of a smart power system. The purposes of the study are:

• Rearranging the overhead power transmission lines of Dhaka city and adjoining area.
• Reducing land requirements for towers
• Recommending future power transmission lines route and type (Overhead and Underground) In the presentation, the following options were discussed
• Converting existing overhead lines (OHL) to underground (u/g) power cable lines;
• Merging two or more existing/future OHLs in a single line with Multi-Circuit Towers (quadruple, sextuple, etc.);
• Utilizing Compact OHL Design (reduced ROW);
• Diversion of OHL routes;
• Up-rating of existing OHL (replacing conventional conductor by HTLS* type) and dismantling redundant parallel OH line;
• Combination of above solutions.

For developing cost-effective towers, consultants discussed Multi-Circuit /Voltage Towers Arrangement (400/230kV) and Compact Towers with insulated cross arms. The advantages and disadvantages of the second option were also elaborated. Now the stakeholders would review and comment for consultants for finalizing the report. The consultant is also studying route maps and documents of Bangladesh Railway for a “Dhaka City Circular Railway” for assessing the impacts of the power transmission network.

By December 2022, the 400 KvA power transmission line from Payra to Dhaka across the Padma River would come into operation. Another 400 KVA line from Bibiyana, Habiganj is already in operation. PGCB and distribution utilities are optimistic that by 2025 the power system will be in a position to ensure quality uninterrupted supply to all.

Power System Efficiency

Power system efficiency is measured by certain metrics. In a power supply chain, there can be momentary and sustained interruptions. Momentary interruption is a brief loss of power delivery to one or most customers caused by the opening and closing of an interrupting device. It is usually less than 5 minutes. Sustained interruptions last more than 5 minutes. SAIDI, CAIDI and SAIFI as well as CAIFI, MAIDI and MAIFI are the utility reliability metrics.

The most important conceptual difference between the two is whether they are resolved automatically using a “recloser” device. It is an automatic high voltage switch that shuts off power when trouble occurs. It then automatically tests the electrical line to determine whether the trouble is removed. In case of a temporary problem, the recloser automatically restores the power.

SAIDI refers to the “System Average Duration Index”. It is calculated by multiplying the average duration of customer interruptions by the total number and then diving by the total number of customers. Logically improved response to outages is the most direct way of improving the SAIDI. What we understand from interactions with distribution utilities is that SAIDI in the Bangladesh power system has improved significantly over the last few years.

SAIFI is “System Average Interruption Frequency Index”. It is calculated by dividing the total number of customers interrupted by an outage by the total number of customers in the system. SAIFI is improved by reducing the frequency of outages through better preventive maintenance. Tree trimming is a common way. But reducing the number of customers interrupted during outages through reclosers and fuses are other ways.

CAIDI is the “Customer Average Interruption Duration Index”. It is calculated as the total minutes of customer interruption divided by the total number of customers interrupted. CAIDI describes the average time required to restore service. CAIDI improvement strategies automated call out of trouble-shooters and crews for faster outage resolutions.

CAIFI is the “Customer Average Interruption Frequency Index”. CAIFI is calculated by dividing the number of interruptions by the number of customers experiencing interruptions.

MAIDI is the “Momentary Average Interruption Duration Index”. MAIFI is “Momentary average Interruptions Frequency Index”. 

Capturing the above data to calculate the indices is important for utilities to improve efficiency. BERC should have the parameters, which the power utilities must comply with. This should be regularly reported to BERC for their monitoring and evaluation purposes.

Conclusion

From grid-connected 4,942MW installed capacity in 2009 to 22,348MW in 2022 is a huge leap in the context of a country like Bangladesh. Policymakers of course now realize the reality of integrated power and energy system planning, simultaneous development of all segments of the power supply chain, modernization of power systems for intensive monitoring and control, and ensuring efficiency. From the initiatives launched across power and energy systems, there is a hope that if not by 2025, by 2030 Bangladesh would have a robust power sector, modern and efficient with a proper price tariff structure as well for reaching SDG7 targets.