A SEMINAR ON UNDER WATER WINDMILL
UNDER WATER .pptx (Size: 577.07 KB / Downloads: 917)
What is it ?
An Underwater windmill like a device that extracts power from the tides.
Renewable energy technologies are becoming an increasingly favourable alternative to conventional energy sources to assuage fossil fuel related issues. Tidal energy offers a vast and reliable energy source. This technology is similar to wind energy technology, with the rotor blades driven not by wind power but by tidal currents. The gravitational pull of the moon produces a swift tidal current, which spins the long blades of the turbine . Which in turn produces electricity via different parts of underwater windmill . This Energy derived from the moon that now helps to power a small arctic village.
Why it is called as “underwater windmill” ?
"Basically it's like putting a windmill in the water," said Bjorn Bekken, a project manager for Hammerfest Strom.
Or as it’s looking like a wind mill & are installed on the ocean floor and large river bed , that means these are under the water.
PRINCIPLE OF OPERATION
In simple a underwater windmill consists of a number of blades mounted on a hub (together known as the rotor), a gearbox, and a generator.
The hydrodynamic effect of the flowing water past the blades causes the rotor to rotate, thus turning the generator to which the rotor is connected via a gearbox.
The gearbox is used to convert the rotational speed of the rotor shaft to the desired output speed of the generator shaft.
The electricity generated is transmitted to land through cables.
There are two types of underwater windmill
In horizontal axis underwater windmill , the rotor shaft is parallel to the direction of the flow of water.
In vertical axis underwater windmill , the rotor shaft is perpendicular to the direction of the flow of water.
The turbines can convert kinetic hydro energy into power ranging from 25 kW to 250 kW, depending on turbine size and current.
Kinetic energy is converted to mechanical power in a nacelle within the turbine.
Underwater ( tidal) turbines are a fairly straightforward concept, as far as cutting-edge energy technology goes.
They are essentially windmills installed onto an ocean floor or river bed.
The underwater current produced by the tides spins blades arranged like an airplane propeller.
These turbines are attached to a gear box, which is connected to an electrical generator.
This produces the electricity that is carried by cable to shore.
Once it's plugged into an electrical grid, the electricity can be distributed.
Tides play a very important role in the formation of global climate as well as the ecosystems for ocean habitants. At the same time, tides are a substantial potential source of clean renewable energy for future human generations. Depleting oil reserves, the emission of greenhouse gases by burning coal, oil and other fossil fuels, as well as the accumulation of nuclear waste from nuclear reactors will inevitably force people to replace most of our traditional energy sources with renewable energy in the future . Tidal energy is one of the best candidates for this approaching revolution. Development of new, efficient, low-cost and environmentally friendly hydraulic energy converters suited to free-flow waters. This type of machine, moreover ,can be used not only for multi-megawatt tidal power farms but also for mini-power stations with turbines generating a few kilowatts. Such power stations can provide clean energy to small communities or even individual households located near continental shorelines, straits or on remote islands with strong tidal currents.