HYDROPOWER SYSTEMS
Small hydropower Powerhouse station
What is a Hydropower System?
Small hydropower systems are very efficient and are considered as one of the lowest cost forms of renewable energy (clean and reliable electricity) available till date. The energy output sits between 100kW and 10MW. It is an environmentally friendly solution that requires (in most cases) a “run-of-river” that needs construction of a simple weir with minimum/without water storage. As mostly agreed by the experts (British Hydropower Association) in the industry, of all the renewable energies (wind, wave and solar power) the small hydropower system has key advantages as listed below:
* A high efficiency of 70 - 90%. By far the best of all energy technologies.
*A high capacity factor (typically >50%), compared with 10% for solar and 30% for wind.
* A high level of predictability, varying with annual rainfall patterns.
* Slow rate of change; the output power varies only gradually from day to day (not from minute to minute).
* A good correlation with demand.
* It is a long-lasting and robust technology; systems can readily be engineered to last 50 years or more.
The energy crisis experienced throughout most of Nigeria is experienced by millions of people, everyday!
There are sustainable solutions available to explore in certain regions of the Nigeria. Lagos is a prime example. Surrounded by water it is perfect for the exploration of hydropower systems. Yet it is not being used to its full potential.
Hydropower systems can help ease the demand of energy within regions of Nigeria.
How does it work?
We use the British Hydropower Association’s simple explanation as the best way to describe our scheme of choice - “Small Run of River hydropower Scheme”.
This simple, highly efficient and low-cost scheme (100kw – 10 Mw) works as follows:
* Water is taken from the river by diverting it through an intake at a weir.
* In medium or high-head installations, water may first be carried horizontally to the forebay tank by a small canal or ‘leat’.
* Before descending to the turbine, the water passes through a settling tank or ‘forebay’ in which the water is slowed down sufficiently for suspended particles to settle out.
* The forebay is usually protected by a rack of metal bars (a trash rack) which filters out water-borne debris.
* A pressure pipe, or ‘penstock’, conveys the water from the forebay to the turbine, which is enclosed in the powerhouse together with the generator and control equipment.
* After leaving the turbine, the water discharges down a ‘tailrace’ canal back into the river.
Small Run of River systems have the advantages of a long operational life time with minimal maintenance.