Ecological aspects

The building of a small power plant cannot be envisaged without first considering its impact on the environment.

It is noteworthy that no other field of energy technology offers such development potential in renewable resources, which are immediately available, and, in comparison with other standard electric-production methods, easy to operate at financially bearable prices.

It is however necessary to find a fair compromise between the use of a locally available, renewable energy, and the preservation of the environment. The laws that govern fishing, energy, and water supply constitute the legal framework of all implementations.

With this viewpoint, various steps can be taken which reduce the impact of a small plant on the environment, or even which improve both landscape and environment with respect to initially prevailing conditions:

• Establishing means by which fishes and invertebrates can cross thresholds and barriers.
• Ensuring that a residual discharge is maintained in the short-circuited arm.
• Ensuring that the flow-rate in the short-circuited arm is adequate.
• Basins should not be emptied at low water.
• Creation of life-sustaining areas in the basins.

It is interesting to note that replacing one GWh (corresponding to the average electric consumption of 220 households) of mixed electricity in Switzerland by one GWh of hydraulically produced electricity reduces the production of CO2 by 11.8 tons. The reduction even reaches 481 tons when the comparison is made with the emissions released by one GWh produced by the European network (Source Eurelectric).

Since our society needs energy and human activities pollute the environment, the most reasonable attitude consists in choosing the least penalizing means of production.