Editing Small hydro (section)

==Project Design==
Many companies offer standardized turbine generator packages in the approximate size range of 200&nbsp;kW to 10 MW. These "water to wire" packages simplify the planning and development of the site since one vendor looks after most of the equipment supply. Because non-recurring engineering costs are minimized and development cost is spread over multiple units, the cost of such package systems is reduced.  While synchronous generators capable of isolated plant operation are often used, small hydro plants connected to an electrical grid system can use economical [[induction generator]]s to further reduce installation cost and simplify control and operation.

Small [[Run-of-the-river hydroelectricity|"run of the river"]] projects do not have a conventional dam with a reservoir, only a [[weir]] to form a headpond for diversion of inlet water to the turbine. Unused water simply flows over the weir and the headpond may only be capable of a single day's storage, not enough for dry summers or frozen winters when generation may come to a halt. A preferred scenario is to have the inlet in an existing lake.

Modular “micro hydrokinetic” systems have been developed for [[Acequia|irrigation canals]].<ref>{{Cite web|url=https://www.ge.com/reports/canal-plus-these-tiny-turbines-can-turn-man-made-waterways-into-miniature-power-plants/|title=Canal Plus: These Tiny Turbines Can Turn Man-Made Waterways Into Power Plants|last=Noon|first=Chris|date=2019-09-05|website=GE Reports|language=en-US|access-date=2019-09-28}}</ref> "[[Irrigation district]]s across the U.S. have installed power plants at diversion points and in-canal drops, which are traditionally used for flow measurement, to stabilize upstream heads and to dissipate energy where there is significant elevation change throughout the canal system."<ref>{{Cite web|url=https://www.hydroreview.com/2017/10/01/capturing-untapped-potential-small-hydro-in-irrigation-canals/|title=Capturing Untapped Potential: Small Hydro in Irrigation Canals|date=2017-10-01|website=Hydro Review|language=en-US|access-date=2019-09-28}}</ref>

Countries like India and China have policies in favor of small hydro, and the regulatory process allows for building dams and reservoirs. In North America and Europe the regulatory process is too long and expensive to consider having a dam and a reservoir for a small project.

Small hydro projects usually have faster environmental and licensing procedures, and since the equipment is usually in serial production, standardized and simplified, and the civil works construction is also reduced, the projects may be developed very rapidly. The physically smaller size of equipment makes it easier to transport to remote areas without good road or rail access.

One measure of decreased environmental impact with lakes and reservoirs depends on the balance between stream flow and power production. Reducing water diversions helps the river's ecosystem, but reduces the hydro system's [[return on Investment]] (ROI). The hydro system design must strike a balance to maintain both the health of the stream and the economics.

Part of the balance between a small hydro project's return on investment and environmental concern is the proximity of the project to the national power grid. The more isolated a small hydro project is the more cost effective its construction will be. <ref name=":4">{{Cite journal |last1=Kuriqi |first1=Alban |last2=Pinheiro |first2=António N. |last3=Sordo-Ward |first3=Alvaro |last4=Bejarano |first4=María D. |last5=Garrote |first5=Luis |date=2021-05-01 |title=Ecological impacts of run-of-river hydropower plants—Current status and future prospects on the brink of energy transition |journal=Renewable and Sustainable Energy Reviews |volume=142 |pages=110833 |doi=10.1016/j.rser.2021.110833 |issn=1364-0321|doi-access=free |bibcode=2021RSERv.14210833K }}</ref>