Ineffective operation and maintenance (O&M) at hydropower facilities can mean that the full benefits of hydropower are not realised, as can often be the case in developing countries.
Following hydropower meetings in Switzerland in 2016 and Ethiopia a year later, key stakeholders agreed on the need to prepare hydropower O&M strategies for countries with low O&M capabilities and challenging business environments. The World Bank teamed up with different representatives from the hydropower community and recently published the report entitled Operation and Maintenance Strategies for Hydropower— A Handbook for Practitioners and Decision Makers (See p42 of the May 2020 issue of IWP&DC for more details).
The International Hydropower Association (IHA) lent its support to the project and provided six case studies which have been published in a separate report. Their aim is to illustrate the lessons learned from the implementation of selected O&M strategies, while sharing views on remaining challenges and future directions. The case studies are:
Statkraft’s Assets (180MW - six facilities) in Brazil.
Mount Coffee (88MW) in Liberia.
Kainji and Jebba (1338MW - two facilities) in Nigeria.
New Bong Escape hydropower project (84MW) in Pakistan.
Nalubaale and Kiira (380MW - two facilities) in Uganda.
Salto Grande (1890MW) in Uruguay/Argentina.
Statkraft Energias Renovaveis, Brazil
In July 2015, Statkraft took over Brazilian company Statkraft Energias Renovaveis (SKER), an existing company with almost 316MW of installed capacity of which 188MW is hydropower generation. Statkraft implemented its O&M optimisation methodologies for the Brazilian plants which created to annual savings of US$3.7 million and a projected increase in profits of US$29 million after 2017. Recent expansion of Statkraft’s operations in Brazil led to the acquisition of eight additional operational hydropower plants in the state of Espírito Santo in 2018, representing a total installed capacity of 131.9 MW. Plans are underway to bring these hydro plants to standard O&M levels by 2020.
The development of new renewable energy technologies is creating new challenges for operating hydropower assets worldwide, and will result in some key trends in O&M:
Increased penetration of variable renewable technologies can result in increased operating costs and underscores the need for even greater overall efficiency as a key target.
Since contract and business models are changing, a competency-based continuous improvement process will need to be implemented.
Digitalisation offers solutions for revenue optimisation and cost reduction through automated, smarter O&M processes, enabled by enhanced digital monitoring systems and predictive analytics.
Mount Coffee Hydropower Plant, Liberia
After years of civil unrest in the 1990s, culminating in the destruction of the Mount Coffee hydropower site, the facility has been fully rebuilt. Over this time, Liberia Electricity Corporation (LEC) ost its experience and expertise in operating hydropower facilities. So in 2016, in an effort to secure sustainable generation, LEC awarded a five-year O&M and training contract to Swiss firm Hydro Operation International (HOI). This means that HOI will:
Be responsible for the O&M of the plant according to international standards for a period of five years, during the anticipated development period of the transmission and distribution grid in Liberia.
Establish O&M procedures for sustainable operation of the plant and be responsible for its implementation over the five-year period.
Train local staff and share skills so that they have the necessary skills to operate the plant with little to no assistance.
However, it became apparent that after receiving on-the-job training, there is a tendency for outward migration of staff who choose to leave the plant for other utilities or the private sector, particularly if more competitive salaries are offered by external companies with better on-site living conditions. Long-term sustainable O&M is only achieved if the O&M is locally staffed, with managers and technicians duly trained and motivated.
As Mount Coffee is a relatively remote site, it became clear that it needs to be provided with suitable housing, health, recreation, and other facilities for O&M staff to allow permanent residence onsite. While an individual performance reward system was needed to acknowledge progress, commitment, and dedication of trainees.
Other lessons learned include:
Preparing multi-year budgets in advance and allocating reserves for major maintenance works and overhauls.
Having a properly funded maintenance programme would allow additional protection and monitoring systems to ensure early detection and monitoring of damage caused by grid instability issues.
The Mount Coffee hydropower plant
Kainji-Jebba Hydropower Complex, Nigeria
Since Mainstream Energy Solutions Lt. (MESL) took over the Kainji-Jebba hydropower complex in 2013, the company has undertaken a capacity recovery programme to restore the two plants. Capacity has doubled from 460MW to 922MW, out of an overall installed 1340MW. Through a 30-year concession agreement with the government of Nigeria, MESL is responsible for O&M at the Kainji-Jebba complex.
Commissioned in 1968 and 1984 respectively, Kainji and Jebba hydropower plants are operating at 69 percent of installed capacity, with plans to reach full capability by 2025. MESL has plans to implement overall improvement in the O&M processes and practices through:
Implementation of computerised maintenance management systems.
Implementation of reliability-centred maintenance to optimise asset availability and minimise maintenance costs.
Measures geared toward obtaining certification under ISO 9001.
Optimisation of the inflow forecast system and operation tools for more accurate flood management and generation projections, plus better understanding and coordination of operations with downstream water users.
Increasing overall plant capability. The Kainji facility was originally designed for 12 generating units but only eight have been installed - even though the intake gates, penstock, foundation, and civil structure at the machine hall level have all been constructed for the remaining units. A 200MW capacity extension should be completed in about five years, with commercial operation expected to start at the end of the year 2023.
New Bong Escape Hydropower Project, Pakistan
Laraib Energy Limited is a subsidiary of the Hub Power Company in Pakistan, and is the owner and developer of the 84MW run-of-river New Bong Escape (NBE) Hydroelectric Power Complex, on the Jhelum River in Azad Jammu and Kashmir. The complex was commissioned in 2013 but a number of reliability issues were experienced during the first year of operation, which led to lower overall availability.
Implementation of the O&M strategy at NBE has resulted in results such as:
Improvements in overall plant reliability.
Achieving excellence in operations through various continuous improvement initiatives being implemented at all levels.
Improved employee engagement and retention
Implementation of the safety management system
Achieving synergies with operations, human resources, finance, and IT by leveraging expertise at head offices and various sites
Improvements in compliance with lenders and other regulatory bodies due to better coordination with the O&M team.
Nalubaale-Kiira Hydropower Complex, Uganda
Uganda Electricity Generation Company Ltd (UEGCL) has executed a 20-year operational, management, and maintenance concession to Eskom Uganda Limited (EUL), for the Kiira and Nalubaale Power Stations.
The generating units at Nalubaale hydropower site were installed between 1954 and 1968 and were refurbished between 1990 and 1996. Currently, a substantial number of components are obsolete and difficult to replace due to unavailability of spares.
Some of the positive aspects of the current O&M contract with Eskom Uganda Limited include:
Transfer of knowledge – EUL has facilitated knowledge and skills transfer to a number of trainees from academic institutions as part of internship programmes.
Modernisation - The operator has modernised some of the critical plant systems and thus reduced the number of forced outages at the Nalubaale Power Plant.
Salto Grande Hydropower Complex, Uruguay/Argentina
The Comisión Técnica Mixta of Salto Grande (CTMSG) is a binational facility, jointly owned by Uruguay and Argentina. The O&M programme is carried out by the staff of the CTMSG.
The binational organisation says that one of the greatest achievements of O&M at the Salto Grande Project has been its ability to achieve technical excellence and the professional attitude of its staff. In addition, the strategic and economic importance of the scheme in the electrical systems of both countries, has made it possible to obtain financing from both governments to meet annual budgets. Other positive aspects include:
Improvements in primary maintenance practices, supported by procedures and experience from 40 years of operation. Monitoring of ageing equipment enables early fault detection.
Troubleshooting with internal specialised personnel has successfully resolved technical issues.
Planned maintenance outages have been successfully coordinated to coincide with the annual low flow period of the river, reducing losses in revenue.
Some of the drawbacks of the current O&M strategy include:
Long-term planned outages have in some cases not been possible, due to network conditions or other considerations. In these cases, efforts were made to extend working hours through extra shifts or overtime in order to reduce overall outage duration
Extended periods of roughly seven years between each planned maintenance outage could result in faults occurring undetected. To prevent this, an extensive set of new predictive monitoring techniques were implemented such as non-destructive tests, on-line vibration monitoring, and partial discharge control.
World Small hydropower Development
The United Nations Industrial Development Organisation and the International Centre on Small Hydro Power have jointly developed The World Small Hydropower Development Report 2019: Case Studies.
The report comprises 18 case studies of successful small hydropower (SHP) implementation in a range of communities and gives a more detailed, practical perspective on the transformative potential of SHP and best practices. It aims to make lessons learned from such experiences easily accessible, forming a knowledge base that can benefit communities, decision-makers and developers elsewhere. The following aspects of SHP development are covered in the case studies.
SHP for productive use:
While lack of access to electricity holds back economic development, SHP can create new opportunities for local businesses by providing power infrastructure. This has been demonstrated by the 165 SHP projects developed under the Sarhad Rural Support Programme in Pakistan and the Gura SHP developed by the Kenya Tea Development Agency.
SHP for social and community development:
Lack of electricity also constitutes a significant barrier to human, social and community development, specifically impacting vulnerable groups, including women and young people. The report gives examples of SHP projects in the Dominican Republic, Nicaragua, Zambia, Tajikistan, Japan, the Democratic Republic of the Congo and China that demonstrate how SHP can create conditions for communities to improve their quality of life.
Access to financial resources is one of the most common barriers to SHP development due to high upfront investment required for launching a project. However, innovative mechanisms have been developed by some international and local banks. For example, the Risk Sharing Framework of the European Bank for Reconstruction and Development offers local partner banks funded or unfunded risk participation schemes. This supported the development of the Akhmeta SHP in Georgia. Ping An Bank, a commercial Chinese bank, also offers customised financial assistance for SHP construction and operation in poverty-stricken areas of the country.
Technology, innovation and smart SHP:
SHP development can also be restricted due to a lack of suitable sites. However, case studies demonstrate that a range of technical solutions exist to help adapt technology and bring it to more communities. These include using existing hydro-technological infrastructure for the installation of an SHP, as in the case of the Zagrody SHP in Poland; and hydrokinetic turbines developed by Smart Hydro Power which can be installed in rivers but also in existing infrastructure such as canals or water regulation dams.
Incentive policies for SHP development:
Another common barrier to SHP development is a lack of a regulatory framework that would encourage the use of SHP and make the sector more attractive for investment. A Panama case study demonstrates how SHP development can accelerate with the support of appropriate incentive policies.
Unregulated SHP development can result in significant ecological impact. Two case studies outline the measures taken in China and Austria to promote SHP construction and rehabilitation in line with the principles of ecological sustainability.