Since wave energy mainly exists near the
sea level, those rigidly fixed devices based on the coast or the
seabed will be affected by the
subsidence of the tidal
sea level (10 meters) (when the
sea level is low, the function will be lost or the efficiency will be reduced or the cost will be increased), which will not be stable and efficient. Disadvantages of economically harvesting wave energy
[0014] ⑵ Insufficient design to deal with the highly corrosive marine environment, mainly reflected in the failure to isolate the marine environment from the precision power generation device
The power device based on the mechanical rod cannot realize completely isolated
power transmission (the internal precision parts are hard to avoid
corrosion damage), the bearing of the swing reversing part is stressed and the environment is harsh and the life is short; the air exchanged by the
power transmission It is directly taken from the surrounding environment of the device, and it is difficult to isolate the gas with
seawater droplets from invading and corroding vulnerable power components such as impellers
It is mainly reflected in the fact that for devices that work in a purely mechanical way, the supporting or conversion joint bearings bear the
impact of all the conversion forces of
waves, and the force is large, and most of them will be exposed to the marine environment and have a
short life; devices based on air bags have two problems. Unfavorable factors affect the service life: ①Repeated large-scale deformation movement under
high pressure (only
large deformation can produce sufficient internal volume changes to drive the impeller to generate
electricity), and high-amplitude long-term fatigue under the harsh conditions of direct
seawater Cause fracture or decrease in elasticity; ②From the consideration of high efficiency, this part of the component must be as soft as possible (inner
volume change requirements), so its thickness and strength are limited, and to obtain wave energy, this part of the component is designed to directly meet the waves, the waves The destructive force is sometimes huge (such as the
impact of a huge wave caused by an instant gale or the hammer blow when falling)
In addition, the movable or soft parts bear all the
impact force of the sea wave or its conversion force, and there is no force threshold protection design
Rapidly damaged when repeatedly impacted by larger waves
[0016] ⑷Many devices do not have the ability to accurately adjust the direction of incoming waves
If the
wave force conversion device cannot be adjusted to face the fluctuation head-on, its conversion efficiency will inevitably decrease
[0017] ⑸Insufficient design of fixing method
In addition to the fact that the device directly fixed on the
seabed is affected by the tide, there are also two problems with the floating device: ① The anchor chain brings restrictions and drag to the fixed end of the device
For the device based on horizontal swing, the fixed end is affected by the
joint action of the anchor chain's own weight and fixed traction, so the swing is limited and the efficiency is reduced
For the device that moves up and down on the vertical water surface, it will be dragged and tilted to hinder the vertical movement, reducing the efficiency
②The fixed anchor chain only considers the fixation of a single device, lacks the coordinated design of the close combination of multiple devices, and does not have the ability to obtain
wave force energy in a large area (
wave force energy is dispersed and distributed, and it needs to cover a large area to cover the water surface to obtain commercially valuable energy)
Many power generation devices use hydraulic components as the energy-transforming medium and a large number of mechanical bearings require
lubrication, which involves the use of engine oil, and the engine oil is easy to leak without complete sealing, causing
pollution around the device