Wave power plant: working principle

Waters of the World Ocean hide in themselves a myriad of wealth, the main of which, perhaps, are boundless energy sources in the form of sea waves. For the first time, the use of the kinetic energy of rolling on the shore was thought in the 18th century in Paris, where the first patent for a wave mill was presented. Now the technology has moved far ahead, and the first commercial wave power plant was set up by joint efforts of scientists, which was launched in 2008.

Why is it profitable?

It's no secret that the natural resources are on the verge of exhaustion. Reserves of coal, oil and gas - the main energy sources - are coming to an end. According to the most optimistic forecasts of scientists, reserves will last for 150-300 years of life. Nuclear power also failed to meet expectations. Great power and productivity pays for the costs of construction, operation, but the problems of dumping waste and damaging the environment will soon be forced to abandon them. For these reasons, scientists are looking for new alternative sources of energy. Wind and solar power stations are already operating . But with all their merits, they have a significant drawback - low efficiency. It will not be possible to meet the needs of the entire population. Therefore, new solutions are needed.

To generate electricity, the wave power plant uses the kinetic energy of the waves. According to the most conservative estimates, this potential is estimated at 2 million MW, which is comparable to 1000 full-power nuclear power plants, and one meter of the front of the wave accounts for about 75 kW / m. At the same time, there is absolutely no harmful impact on the environment.

General scheme of work

Wave power plants are called floating structures that are able to convert the mechanical energy of wave motion into electrical energy and transmit it to the consumer. In doing so, try to use two sources:

1. Kinetic reserves. The sea shafts pass through a large diameter pipe and rotate the blades, which transmit the force to the electric generator. The pneumatic principle is also used - water, penetrating into a special chamber, displaces oxygen from there, which is redirected along the channel system and rotates the turbine blades.
2. Energy rolling. In this case, the wave power plant acts as a float. Moving in space along with the wave profile, it makes a turbine rotate through a complex system of levers.

Different countries use their own technologies to transform the mechanical movement of waves into electricity, but they have the same scheme of action.

Disadvantages of wave power plants

The main obstacle to the extensive introduction of wave power plants is their cost. Due to the complex design and complex installation on the surface of sea water, the cost of implementing such facilities is higher than for the construction of a nuclear power plant or thermal power plant.

In addition, there are a number of other shortcomings, which are mainly associated with the emergence of socio-economic problems. The thing is that large floating stations create a danger and interfere with navigation and fishing - a floating wave power station can simply displace a person from fishing areas. Environmental consequences are also possible. The use of installations considerably extinguishes the sea shafts, makes them smaller and does not allow to break into the shore. Meanwhile, waves play an important role in the process of gas exchange of the ocean, cleaning its surface. All this can lead to a shift in ecological balance.

Positive aspects of wave power plants

Along with its shortcomings, the wave power plant also has a number of advantages that have a positive impact on human activities:

• Installations, due to the fact that they extinguish the energy of the wave, can protect coastal structures (berths, ports) from destruction by the force of the ocean;
• The generation of electricity occurs at minimal cost;
• High wave power makes the wind farms economically more profitable than wind or solar power stations.

The reserves of energy are also available on land, mainly rivers. The construction of stations on bridges, ferries, berths is the prospect of the development of this area of power generation.

Problems to be solved

The main task facing the scientific community now is to improve the design, which will reduce the cost of electricity generated by wave power plants. The principle of operation should remain the same, but new technologies and materials will be used to create the installations.

The average wave power is 75-85 kW / m - it is on this range that most stations are tuned. However, during the storm, the force of the sea shafts increases several times and the danger of destruction of the installations is created. More than one blade was wrinkled or bent after a storm. To solve this problem, scientists use artificial methods to reduce the specific power of waves. One of the problems is that the massive use of wave stations will lead to climate change. Generation of electrical energy is carried out due to the rotation of the Earth (this is how waves are formed). Ubiquitous use of stations will cause the planet to rotate more slowly. A person will not feel the difference, but this will destroy a number of currents that play an important role in the heat exchange of the Earth.

The world's first pilot wind farm

The first wave power plant appeared in 1985 in Norway. Its power was 500 kW, and she was a prototype. Its principle of operation is based on cyclic compression and expansion of the environment:

• A cylinder with an open bottom is immersed in water so that its edge is below the trough of the wave - its lowest point;
• Periodically, incoming water compresses the air in the internal cavity;
• When a certain pressure is reached, a valve opens, which gives a passage of compressed oxygen to the turbine.

Such a power plant produced 500 kW of energy, in order to be sufficient to confirm the effectiveness of facilities, which contributed to their development.

The world's first industrial power station

The world's first installation of an industrial scale is Oceanlinx in the water area of Port Campbell, in Australia. It was put into operation in 2005, but then it was sent for renovation and in 2009 it was re-earned, which is why now both tidal and wave power plants are used in the region. Its principle of operation is as follows:

1. Waves periodically run into special chambers, causing the air to shrink.
2. When the critical pressure is reached, the compressed air is rotated through the network of channels by an electric generator.
3. To capture the movement and strength of the waves, the turbine blades change their angle of inclination.

The plant's power was about 450 kW, although each station section is capable of delivering from 100 kWh to 1.5 MWh of electrical energy.

The world's first commercial wind farm

The first wave power plant of commercial purpose earned in 2008 in Agusadora, Portugal. Moreover, it is the first installation in the world that uses directly the mechanical energy of the wave. The project was prepared by English company Pelamis Wave Power.

The structure of the structure includes several sections that are released and raised together with the wave profile. The sections are hinged to the hydraulic system and driven during operation. The hydraulic mechanism causes the rotor of the generator to rotate, which is why electricity is generated. The wave power stations used in Portugal have pluses and minuses. The advantage of the installation is a large capacity - about 2.25 MW, and in the possibility of installing additional sections. Lack of installation of the system is one - there is a difficulty with the transmission of electrical energy through wires to the consumer.

The first wave power station in Russia

In Russia, the first wind farm appeared in 2014 in Primorsky Krai. The team of scientists from the Ural Federal University and the Pacific Oceanological Institute of the Far Eastern Branch of the Russian Academy of Sciences was engaged in the development. The installation is of an experimental nature. Its feature is that it uses the energy not only of waves, but also of tides.

In Moscow, it is planned to build a research laboratory, which will develop and create the first domestic float station. Perhaps, after this, wave power stations in Russia will also have an industrial or commercial purpose.