Information

Clearwater Hydro specialises in establishing small scale, low impact, hydro generation sites. Our schemes are often referred to as 'run of the river' operations as we have no large dams or storage lakes. Our schemes essentially consist of three elements. The key elements required for a workable scheme are:

  1. High Head (70m plus), or
  2. High Flow (3 cumecs plus), or
  3. High Head and High Flow, and
  4. Reasonable Vehicle Access possible, and
  5. The local power network nearby, and
  6. Last but not least an enthusiastic landowner

Element 1 – Water Collection

The first stage of our generation schemes is to collect water and direct it into a penstock (pipe). This can be achieved by constructing a weir over the full width of the stream / river, or by constructing a diversion channel over a portion of the stream / river (used in instances of high water volumes). An intake is then placed on the upstream side of the weir, or within the diversion channel, to direct water into the penstock. Our weirs are typically between 1 and 3 metres in height, which minimises the extent of upsteam ponding. In instances where weirs are constructed, we ensure that there is a ‘fish pass’ so that fish and eel species can continue to migrate up and down the stream / river.

Element 2 – Water Transportation

Once water is directed into the intake, it is then transported via penstocks (pipes) towards the generation turbines, which can vary in length up to 4km. Where practical and feasible, we bury penstocks to mimimise the impacts on farming operations. By containing water in this manner, and utilising gravity, we are able to maximise the pressure at which water falls towards the generation turbines (Stage 3). The vertical height difference (in metres) between the intake (Stage 1) and the generation turbines (Stage 3) is commonly known as 'head'. The greater the amount of 'head', the greater the amount of water force available for generation.

Element 3 – Generation

The water transported via Stage 2 is utilised to spin turbines, which are connected to generators that create electricity. The electricity generated then passes through transformers which modify the electrical voltage so that it can be transmitted over the local power network. The turbines and generators are housed within a shed the size of a large car garage. Once the water has passed through the turbines, it is returned to the adjoining river or stream via an energy dispersion facility.

For more information, see this fact sheet about small hydro schemes from the Energy Efficiency and Conservation Authority (EECA).

Below is an interactive diagram of one of our schemes. Hover over the boxes to see a photo from each stage of the hydro scheme.

Various Stages of Construction
Various Stages of Construction
Various Stages of Construction
Various Stages of Construction

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