Operations and Maintenance

  • Local/remote management of operations of hydropower facilities
  • Maintenance of hydropower facilities
  • Day-to-day management of hydropower facilities and ancillary works
  • Setup and review of O&M concept and procedures
  • Setup of shut-down, lockout and tagging procedures
  • Water intake management
  • Flood control
  • Health and safety planning
  • Emergency response plan
  • Spare parts inventory/management
  • Unit start-up/shut-down
  • Management of desilting devices


Poor operations and maintenance due to a variety of reasons, including lack of investment, inadequate training or outdated approaches, can result in high outage rates, performance losses and increased operating costs. This in turn, can lead to lost energy production, reduced revenues, and in some cases, dam safety and environmental concerns.

Hydropower systems are capital-intensive assets that have the ability to produce a significant income for many decades, provided they are operated efficiently and maintained to a high standard. Conversely, a hydropower system that is operated sub-optimally can suffer a significant reduction in energy production and therefore income, even though the operating costs remain the same. Consider the difference 10% more income would make if operating costs remained the same?

Depending on the size of the system and how involved the customer wants to be in the day-to-day management of the system, HOI offers different levels of hydropower maintenance and operational support to suit every requirement.

Hydropower systems are designed to match the local flow and head characteristics, and are embedded into the surrounding environment, meaning that each hydropower system will have its unique design and operational characteristics to make it work on a particular site. The extensive knowledge needed to operate a hydropower system is built-up over many years, particularly in respect to debris management which varies depending on the flow conditions and season.

HOI always recommend having a local contact on site, who has the day-to-day responsibility of checking the operation of the hydro system, as it will help them learn all the nuances that relate to that particularly site, and will be able to identify any anomalies in appearance and sound. HOI can provide day-to-day operational support, but finds it most effective to harness our expertise for longer-term hydropower maintenance and operation support.

Operational Support and Maintenance Services cover three main areas of work:

  • Hydropower system routine and non-routine service contracts
  • Hydropower system review and operational optimisation
  • Hydropower system upgrades and improvements

HOI’s hydropower service contracts provide regular preventative maintenance and inspections to ensure reliable day-to-day operation of the plant. The frequency of visits varies depending on the size, type and complexity of the system.

Routine services cover:

  • Turbine functional checks and inspection.
  • Turbine bearing lubrication and inspection.
  • Gearbox inspection.
  • Gearbox oil condition analysis and oil changes.
  • Gearbox bearing inspection and lubrication.
  • Drive belt inspection and replacement.
  • Drive coupling inspection.
  • Generator inspection.
  • Generator bearing inspection and lubrication.
  • Hydraulic system inspection.
  • Hydraulic system oil condition analysis and oil changes.
  • Check all sensors operate correctly.
  • Check controller functions correctly.
  • Inspection of intake area, impounding structures, pipeline, sluice(s).

Hydropower Non-routine Maintenance:

Non-routine maintenance visits often identify faults that require spare parts that are not kept in stock, or by their nature are too mammoth a task to undertake during a routine visit. Moreover, some clients have specific major maintenance tasks they need to be carried out.

Such work can include:

  • Bearing replacement.
  • Changing drive couplings and belts, including realignment.
  • Sensor replacement and calibration.
  • Controller optimisation / reprogramming.
  • Internal (endoscopic) inspections of turbines and gearboxes.
  • Major mechanical / electrical or civil engineering repairs and refurbishments.
  • Pipeline pigging.
  • Pipeline external and internal inspections.
  • Weir condition surveys.
  • Flow rate measurements (to verify turbine performance and consent compliance).
  • Hydraulic accumulator testing and recharging.
  • Electrical inspection and testing.
  • Automated intake screening system maintenance.
  • Fish pass / bypass / eel pass works.
  • Hydro system performance and operational reviews / optimisation.
  • Environmental permit compliance.

As designers and builders of hydropower systems with a swiss know-how and track record, we are uniquely well-equipped to undertake all of your non-routine servicing.

There are many steps involved in taking a hydroelectric project from initial concept to construction. HOI’s expertise extends from conception to commercial operation, starting with site identification and pre-feasibility study, to the construction phase, and finally tests and operation


OEM Equipment Lifecycle Maintenance