Micro hydroelectric: info on incentives, installation requirements, permits, requests and costs. Difference between pico, micro and mini electric.
In Italy we make little distinction betweenmicro, pico and mini hydro. In general, we tend to classify any hydroelectric power plant with an output of less than 100 kW as a plantmini hydroelectric. There are actually three different classifications but they change from state to state.
Pico hydroelectric: refers to plants that produce hydroelectric energy with a power of less than 5 kW. Generally, these are small hydroelectric plants intended for the self-consumption of isolated users.
Micro hydroelectric:it refers to hydroelectric plants with power ranging from 5 kW to 100 kW.
Mini hydroelectric: refers to hydroelectric plants with power ranging from 100 kW to 1000 kW.
Micro hydroelectric, what is it
Although in both cases energy is produced starting from a turbine moved by water, a plant ofmicro electriccannot be compared to a real onehydroelectric power plant.
Themicro electricdoes not include the construction ofdams because it exploits the motion of the water that flows in natural streams: the water that descends makes the turbine turn to generate electricity.
How does a micro electrical system work?
Flowing water moves a turbine, mechanical energy doesturn an alternatorwhich transforms this kinetic energy into electrical energy.
With the availability of a watercourse, a plantmicro hydroelectricit can produce electricity for isolated users. A very convenient system for mountain huts and for housing solutions such as isolated farms or hotels that cannot draw on the national electricity grid.
Micro hydroelectric power plants can be installed in different contexts, even in artificial waterways or tanks. The plants ofelectric picowith a size of 2-5 kW, they have a single turbine placed directly in the water course while for themicro hydroelectricit is necessary to create special adduction channels, loading tanks or detours with penstocks thanks to which part of the running water of the course is taken to operate the turbine. After operating the turbine, the water is returned to the main course and re-enters further downstream.
Micro hydroelectric and construction costs
THEcostsfor the construction of a hydroelectric plantmicro or picothey vary not only according to the installed powers. As stated, for the power plantsmicro hydroelectricthere is the need to carry out civil works (canals, loading tanks, penstocks, intake works ...) and the cost can fluctuate a lot according to the conditions in which they are going to be built. Generally, the return of costs is all the more immediate the less the energy generated is. In a plant pico hydroelectric from the capacity of 3 - 5 kW, with the installation of the turbine directly in the water, there is an economic return in times of less than 6 years. For installed powers above 10 kW, it will take at least 10 years to equalize the investment.
As is the case with other renewables (wind, solar thermal and photovoltaic energy), also in the sector ofpico hydroelectricthere is no shortage of pre-packaged kits. Generally, the kits contain a turbine (the main component of the system), the generator, the inverter (electrical panel) and the accumulators for the storage of the energy surplus produced.
Regarding therequirementsinstallation, it is necessary to have a sufficient water head to operate the turbine. In general, a difference in height of even a few meters is enough to produce satisfactory energy. The water flow must be constant and not conditioned by seasonality (therefore immune tosummer shoals). In dry periods, the flow rate must have a minimum constancy of 0.5 liters per second. Thanks to the jump and flow rate, it will be possible to best size the system and calculate the economic returns.
For the construction of civil structures suitable fordivert the waterintended for the plantmicro hydroelectric, it will be necessary to apply for the release ofConcessionby contacting the Province (the authorization process is managed entirely by the province formini hydroelectricwith a power of less than 3 MW).
For incentives, please read the page:incentives for non-photovoltaic renewables.
Domestic hydroelectric: producing energy from the toilet drain
"Going down" classification and returning to talk aboutpico hydroelectric, researchers from Seoul National University and Korea Electronics Technology Institute (KETI), have developed a device that can generate electricity from water flowing through the toilet drain, making the toilet a clean source of electricity.
Also in this case the kinetic energy of the water flow is converted into electricity but according to a different principle. The device developed by the KETI researchers does not use any turbine but a dielectric material, that is, capable of developing an electric charge as water passes.
The same invention can be applied not only to the toilet drain but also to any tap in the house.
In the photo above, a rustic example of a micro hydroelectric power plant installed in the north of Vietnam.
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