Countries like Scotland are leading the world by example. It is making the switch to renewable sources of energy for good. Although it aims to go 100% on renewable energy by 2020, even right now it isn’t far behind. At present, Scotland generates about 70% of its energy from renewable resources. However, it wouldn’t be possible if the country didn’t utilize its potential for tidal energy. As a part of its great multi turbine tidal energy plan, the country aims to further their present efforts by putting a 150-ton turbine under the sea. This turbine, while in operation, would generate energy for up to 1000 homes.
Tidal Energy Company Atlantis is the largest of its kind in Europe. And right now it is focusing on completing a four-phased MeyGen Tidal Energy Project in coasts of Scotland. The project is one of a kind Multi Turbine Tidal Energy field that will be powering nearly 175,000 Scotland houses after its completion. Right now the project is in the first phase of its development but it has already received a funding of €37 million from EU for its second phase. Here are some interesting facts that you might want to know about it.
Where exactly is it?
The turbines are being installed in the Pentland Firth region which is very near to the Scottish coast. To be exact, they are at a distance of approximately 1.5 Km from the coast. The turbines will always be under a depth of approximately 40 metres. The nearness of the turbines from the coast will make it easier for the operators to access them.
The Pentland Firth is considered as one of the most turbulent oceanic regions. There is no other place in Europe that provides a better opportunity of harnessing ocean tides.
How big is the project?
The project is gargantuan. Right now the company is planning to install 269 turbines at a distance of 160 meters from each other. And if this proves successful then the company is ready to install many more. Atlantis has already taken the area on a lease of 25 years.
Even the dimensions of the turbines are no less. Though they are smaller when compared to wind turbines but still they are huge. An average turbine is about 15m tall and its blades have a diameter of 16m. And together they weigh about 200 tonnes.
How effective will it be?
Each turbine is capable of producing 1.5 MW of electricity. The underwater turbines are as efficient as wind turbines in terms of producing electricity. Moreover, underwater turbines have many great advantages over wind turbines. The wind is not a constant source of energy. But waves, on the other hand, are ever-present. So there won’t be any time when the turbines would stop. And waves carry much more power when compared to wind. For example, an ocean current of 5 knots can provide more power than the wind when it’s blowing at 340 Km/h.
These underwater turbines, in particular, carry one more advantage. Depending upon the direction of the current they can change their direction. Yaw mechanism would help them in making a free 180-degree movement.
How does it work?
Using efficient cranes, the turbines are placed upon already constructed platforms in the ocean. And through cables that run through underwater tunnels, these turbines are connected to Electrical Substation on the coast. When the turbines will move, they will generate electricity and that electricity will reach Electrical Substation. And the Electrical Substation is connected to the nation’s electricity grid. So, it will provide the electricity directly to the consumers.
Won’t it be harmful?
At present this project isn’t expected to cause any harm. It is underwater so it won’t give rise to any problems to the people on coast. No military submarine can enter this region. Waters of this region are too turbulent for fishing.
The fans of the turbines aren’t capable of harming the marine life. They move very slowly, about 12-14 times in a minute. And as far as the turbines are concerned, nothing can blow them away as the bases upon which they are fixed weigh nearly 1000 tonnes.
The only problem with these wind turbines is their cost. They are extremely expensive. Atlantis Resources is facing many financial issues because of this project. But financial support has been provided to them by EU and they are going on with the project.
Some trends in Tidal Energy
1. Tidal Stream Generators:
The density of sea water is 832 times that of air. Further, the salt content and the ions increase the density of sea water. It may be utilized in such a way that a single generator can provide significant power at low rate of water flow. Tidal movement must be at least 2 knots in order to take advantage of the tidal horizontal energy. There are four angles engaged in gaining energy while using stream generators for which the horizontal axis turbines and vertical axis turbines are used. The other two are the oscillating devices and venturi effect generators to produce more electricity.
2. Barrage tidal power generation:
A barrage wall acts as a channel for water to move in and out of the basin or estuary to derive energy in the useful form. Variability in water level outside the basin and inside the channel helps in turbine rotation which results in power generation.
3. EBB generation:
Generation of power when the basin is filled through sluices in the high tide and when the gates are closed; pumping may be used to raise the level of water further. When the water drops, turbine gates are opened for power generation. The cycle repeats twice a day, when there is a drop in water and when the water is filled again. Another interesting feature that is needed to be known is the energy derived from the process is used to start the motor.
4. Flood generation:
Lesser possibility than EBB generation, but power may be generated from this as well. The difference relates to the sea side and basin side in power generation and works effectively in suitable geography.
5. Dual basin types:
Aids in continuous power supply between the two basins. One basin is filled at high tide and the other emptied at low tide and the energy turbines are placed between the two basins. but It is more expensive for individual construction.
Final Words
Tidal Energy has always been called the underdog of sustainable energy. It is not as popular as other sources of renewable energy like solar energy and wind energy. Its high cost is its only disadvantage. But researches are being done to make it more cost-effective. The MeyGen Tidal Energy Project is very important for the development of Multi Turbine Tidal Energy. If it succeeds then it will surely give Tidal Energy the fame that it deserves.