한국에 석유는 없지만 세계 최고 수준의 바다가 있었다! 해마다 기름값 988억 원 돈 버는 세계 최대 조력 발전소｜바다로 전기를 만들다｜시화호 조력 발전소｜다큐프라임｜#골라듄다큐

Summary of Scientific Concepts, Discoveries, and Natural Phenomena

• Tidal Power Generation Principle:
  • Utilizes the difference between high and low tides to generate electricity by controlling seawater flow into an artificial reservoir.
  • Best suited for areas with large tidal ranges and wide water containers but narrow entrances (e.g., bays).
  • Sihwa Lake’s geographical features (existing breakwater, lake holding water, narrow entrance) make it ideal for tidal power.
• Sihwa Lake Tidal Power Plant Construction:
  • Built on an 11.2 km breakwater between Oido and Daebudo islands.
  • Used a circular slab dam construction method involving:
    • Connecting 29 circular cells made of 50cm-wide sheet piles into a cylindrical dam (20.4m diameter).
    • Filling the cylindrical structure with sand to create a dam line resistant to currents.
    • Construction done in dry conditions by pumping out seawater inside the dam.
  • Temporary bypass roads and turbidity prevention barriers were installed for construction.
  • After construction, water turbines, flow control devices, and power generation equipment were assembled and installed.
• Key Components of the Tidal Power Plant:
  • Water Turbine Generator:
    • Composed of a rotor (generates magnetic force) and stator (converts magnetic force to electricity).
    • Water turbine blades are 7.5m in diameter with three blades designed to minimize harm to marine life.
    • The turbine shaft transmits rotational power to the generator.
  • Flow Control Device:
    • Controls the amount of water entering the turbine by adjusting 16 blades.
    • Maintains constant turbine rotation speed to ensure stable electricity generation.
    • Weighs over 1 ton and requires precise assembly with torque-wrenched bolts.
  • Sluice Gates:
    • Eight gates, each 15.3m wide and 12m high, controlling water flow.
    • Constructed with thick stainless steel to resist corrosion and marine life attachment.
    • Roller gates move faster than previous drainage gates to quickly manage water levels.
• Environmental and Ecological Context:
  • Sihwa Lake was severely polluted after seawall construction in 1994, turning into a "lake of death" due to lack of oxygen and ecosystem collapse.
  • To improve water quality, tidal gates were opened twice daily to exchange seawater and lake water.
  • The tidal power plant was designed primarily to improve water quality and secondarily to generate electricity.
  • Expected benefits include improved water quality, enhanced biodiversity, and ecosystem restoration.
• Operational Characteristics:
  • The plant operates as a unidirectional tidal power plant, generating electricity only during high tide.
  • Water is pumped into the reservoir at high tide and released to generate power.
  • Generates power for approximately 500,000 people.
  • Provides a stable power supply unaffected by weather conditions (unlike hydroelectric dams dependent on rainfall).
  • Expected to reduce oil imports by 862,000 barrels annually and cut CO2 emissions by 315,000 tons per year.
  • Generates additional income through carbon credit systems.
• Other Marine Energy Technologies Mentioned:
  • Tidal Current Power Plant (e.g., Uldolmok):
    • Uses fast tidal currents to rotate underwater turbines.
    • Requires locations with high current speeds (>2 m/s) for economic viability.
    • Uldolmok has currents up to 6.5 m/s, making it ideal.
  • Wave Power Generation:
    • Converts kinetic and potential energy of waves into electricity.
    • Uses air chambers and turbines to transform wave motion into power.
  • Thermal Power Generation:
    • Research ongoing worldwide; Korea plans test plant in Jeju Island.
• Global Context:
  • The UK is a leader in marine energy development, aiming to supply 20% of its electricity from ocean energy (15% wave energy, 5% tidal/current).
  • Korea has similar marine conditions and potential for large-scale marine energy utilization.
• Scientific and Engineering Challenges:
  • Precise control of water flow and turbine rotation speed is critical.
  • Construction requires advanced marine structure design, power generation system technology, and energy conversion technology.
  • Continuous monitoring and scientific operation are essential for success.
  • Stepwise filling of the reservoir during commissioning to allow inspection and prevent damage.
  • Corrosion resistance and biofouling prevention are important for submerged structures.

Methodology/Construction Process Summary

• Circular Slab Dam Construction:
  • Install fixed barge as workbench.
  • Install pin piles (pillars) as structural support.
  • Assemble 8 sheet piles into a circular cell.
  • Connect 29 cells to form cylindrical dam.
  • Fill cylinder with sand to create dry dam.
  • Pump out water inside.