n a country like Nepal, where most of the hilly regions are thinly populated and the prospective
consumers are very evenly scattered and small streams are abundant everywhere, pico hydro can be
an answer to the increased energy demand as a centralized large transmission and distribution
system will not be justified in such scenario.
3-phase self excited induction generators are widely used for pico hydro systems as the 3 phase
variety is more common and it is more compact than a single phase induction generator for the same
power output. For the very small units (e.g. 200W-1kW) it is usual to provide a single phase output.
This is because it is simpler to regulate a single phase than all the three phases independently.
However this can result in only a fraction of the rated generator output being used. This may be
acceptable if the prime aim is to produce as much useful power as possible from a given turbine, head
and discharge. Conversely, it may lead to oversized generators.