Oscillating water column wave energy conversion system
"Design and construction of a laboratory sample of wave energy converter with the central idea of oscillating column systems with a maximum power of 100 watts along with the feasibility and technical and economic evaluation of the construction of a 100 kilowatt sample"
" Moderator: Babol Noshirvani University of Technology - Dr. Rouzbeh Shafaqat "
The Mazandaran Sea is the largest lake on earth and fortunately this sea in our country has a deeper coast compared to its neighboring countries and considering that the Mazandaran Sea has suitable waves for the production of renewable energy, in this project conditions of the Mazandaran Sea's waves was investigated and modeled During the year to identify the waves that have the highest probability of occurrence, and the oscillating water column system suitable for the conditions of this sea’s waves was designed and built to be able to produce 100 watts of power in a laboratory scale of 1:10.
Technical, economic and environmental benefits of the project implementation:
- This system is capable of producing clean and free electrical energy.
- The system has a longer service life due to having a PTO system outside the water .
- The system is of multi-chamber type, and this model of systems has higher power compared to single-compartment models.
- The price difference between domestic and foreign samples is 87,314,000,000 Rials, which is almost 613% cheaper than foreign samples.
Summary of the project report :
In this project, at first, due to the high advantages of oscillating water columns, comprehensive studies were conducted on this type of converters, then in the next stage, the characteristics of Mazandaran sea waves were simulated for 17 points along the coastline of Mazandaran province. In this stage, the characteristics of the most probable wave of the Mazandaran sea was extracted. In the next stage, the system was modeled and designed, and in this stage, according to the numerical modeling, Savonius turbine was selected as the best type of turbine, then in the next stage, the system was built in the workshop of the research group, and the system was subjected to various tests to be able to produce electricity equivalent to 100 watts on a laboratory scale, although the results showed that the system has the best performance at a water intake depth of 5 cm and a frequency of 32 rpm.
The cost of the domestic project construction
The costs of wave energy projects can be very different according to the location of the project, because the installation location actually determines the issue of infrastructure as well as the capacity of wave energy sources. The main costs related to sea wave energy systems include the stages of system construction costs, transportation, bracing/foundation, installation, commissioning and maintenance, half-life repairs and deployment. Figure 1 shows the contribution of each of the above parameters in capital costs.
Then the domestic sample was compared with the foreign sample, and the results showed that the domestic sample is almost 6 times cheaper than the foreign sample. As can be seen, in the situation where only one system is considered, the final price for each kilowatt hour is about 1.940 rials, which according to the purchase of renewable electricity by the Ministry of Energy for hydropower plants with a capacity of less than 100 kilowatts, 3.800 rials is a very good price. Considering the power of the system and also considering its operation in half of the year, the return of its investment will be possible in a ten-year period.
Features and benefits of the final product of the project :
* The final system is a multi-chamber oscillating column with a production power of 100 watts on a laboratory scale.
* The production technology of system’s air turbines is available in the country and there is no need to import
* The system has the ability to produce electrical energy from renewable energy sources 24 hours a day.
* Considering that the system is coastal type, it can help the eco-tourism of the region.
* If this system is used throughout the year, the investment return period can be up to 5 years
* The system is 6 times cheaper compared to the foreign model.