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1,839 bytes removed, 16:49, 21 March 2013
moved "Assessment of electricity needs" to hydroelectricity
When several sites are identified, the remoteness of the consumer is another criteria for inclusion in the feasibility analysis. Remoteness means a longer power line and makes monitoring of the plant more difficult. An electrical power line represents a important expense and is a source of powerloss.
===Average waterflow===
The amount of instantaneous waterflow of a river system depends on the rains, which is dependant on the season. The instantaneous waterflow varies from day to day with a minimum therof, located usually at the end of the dry season if it is marked. The concept of average flow has no interest in powerplants "along the waterstream", however, it does allow to better estimate the potential energyoutput of an infrastructure if an accumulation is envisaged. Low water flow, ie the minimum flow of the river during 24h states the minimal poweroutput potential of an installation. If the hydrological observations (measures of the flow of the river) are done for several years, it is possible to know the average minimum waterflow attained annually, or it is possible to observe it every 5 years, or -even more rare-, every 10 years. Indeed, the severity of the drought is variable depending on the year. A flow measure during 365 days can not indicate whether the observed minimum is an exceptional speed (either low or high) or rather an average minimum.
The hydrological data may be essential for the design of the proposed small hydroelectric plant. A lack of flow and thus availability of water will lead to disillusionment when the installation is working due to the large gap between the expected power output and true available power. There is of course no need to seek accurate hydrological data if the power output of the proposed installation is well below the maximum power of the site chosen for the project. Given that the turbine is to be placed near the river, it is highly desirable to know the variations of water level, to avoid seeing water invading the facilities during floods.
===Assessment of electricity needs===
It is difficult at first to estimate the effective electricity output since it depends on the project which is associated with the construction of the hydroelectric powerplant. It is known that the provision of electricity promotes its use. Without any regulation system of the consumption (limiting the amount available to the consumer via electrical switchboard, billing of the consumption).
The lighting of offices is an important element for the development of the electricity grid, as well as the sponsoring of communication facilities such as the telephone network, operation of television channels, computers. The electrical energy is also useful to activate the cooling chain (storage of medicines, vaccines ...). Foremost, we must exclude, in the context of a micro-powerplant, thel use of electricity as a means of heating because consumers will become prohibitive for the small network.
To give a general idea however, an installed capacity of 2kW per family is a correct value to identify the electricity needs in a village community. However, Vietnamese experience transposed to the Philippines cites lower values. Once the provision of electricity for a workshop is also considered, it is sufficient to determine the installed capacity to the whole of the envisaged equipment. In the case of a carpentry, engines consuming more than 1500W are common.
It is also possible to set, among the regular customers of a small network, priority clients such as those that manage a cooling chain for vaccines and drugs, or a surgical hospital. These customers will be supplied as long as possible. These provisions should be exposed to all users as a way to maintain cohesion and avoid conflicts. This regulating system allows to supply electricity to more customers but for a more limited period.
===Constraints for exploitation===

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