Micro-Hydro
Description
Growing the Commons:
"A micro-hydro system converts the potential energy in a stream of moving water into electrical energy. The principles of hydropower are the same whatever the size of the system. Micro-hydro refers to small systems that can be installed by individual homes, businesses or farms.
A system consists of a turbine that converts flowing water into electricity (via a generator); an intake structure some distance upstream of the turbine, where some water is diverted from the stream to the turbine via a pipe; and an outlet to discharge the water back into the stream.
Power generated depends on the flow of water and how far it drops (head). Efficiencies of micro-hydro systems are typically over 70%."
(https://knowledge.growingthecommons.org/doku.php/mhdr/micro-hydro)
Discussion
Growing the Commons:
- What are the benefits of micro-hydro?
"There are all the usual benefits of renewable energy generation, in that it avoids the burning of fossil fuels, with their associated pollution and carbon emissions. Plus it’s one of the more efficient renewable technologies. The load (or capacity) factor on small hydro is typically around 45% (load factor is the ratio of energy output per year to the maximum output if the system works at full-rated capacity all year round). PV is typically around 8-9%, and a 250kW wind turbine is in the 18-22% range, depending on the site.
Cost per kWh delivered is site dependent. Costs are driven by things like site access, grid availability, distance to grid, what civil engineering works have to be done – for example, is there a weir already in place? Is there a fish pass? Do you have to construct a new fish pass, or a new weir completely?
Hydro can provide an income for farm families (selling electricity to the grid) and can give a cost advantage to small-scale industry situated in an old watermill converted to generate electricity.
In the 18th and 19th centuries, when weirs were built across rivers for watermills, they didn’t worry about fish passage; but now when they’re converted to generate electricity, there’s often a requirement in the planning approval to provide a fish pass. So converting old watermills helps fish passage up river valleys.
Water is flowing constantly, and the turbine can be producing electricity 24-7, for approximately 80% of the year - i.e. excluding the driest part of the year, typically the summer months. Therefore it’s ideal for running the pump of a ground source heat pump, and providing all your heating needs, as well as electricity.
They last much longer than any other kind of renewable energy systems. The life expectancy on a well-built, well-maintained system is three generations. Our advisor recently did some work on a system that was installed in 1890, and is still going strong."
(https://knowledge.growingthecommons.org/doku.php/mhdr/micro-hydro)