2.b Wave and tidal energy

Fossil fuel global consumption

75-80%

Reasons for alternative energy

Rising population, higher living standards, and fossil fuel impacts

Flow resources

Resources naturally replenished by the sun and moon's gravity

Current UK jobs in wave and tidal

2,400 jobs

Projected UK jobs in wave and tidal

Over 23,000 in the next decade

Projected UK economic boost from wave and tidal

£6.1 billion in the next decade

Potential UK electricity provision from wave and tidal

Up to 20%

Key UK locations for wave and tidal

Scotland and the South West of England

Effect of increasing wave and tidal capacity

Costs reduce faster

Arguments against wave and tidal energy

Lack of funding elsewhere, disruptive pollution, and unreliability

UK global energy standing

Global leader in tidal energy

Tidal energy predictability

2 high tides and 2 low tides per 24 hours

Main drawback of tidal energy

Very expensive

Tidal energy limitations

Dependent on local geography and economic travel limits

Tidal barrage

A dam-like structure built across a coast or estuary

Wave energy potential compared to tidal

Enormous and much greater

Absorber Design

Utilises vertical rising and falling motion of waves to drive a pump, creating hydraulic pressure that forces air through a turbine.

Attenuator (e.g., Pelamis)

Interconnected semi-submerged buoys aligned parallel to wave direction; adjacent sections articulate to drive hydraulic pistons.

Oscillator (e.g., WaveRoller)

Bottom-mounted seabed flap that oscillates with surge currents to directly transfer kinetic force to a generator.

Oscillating Water Column (OWC)

Waves enter an enclosed chamber, compressing and decompressing air to drive bi-directional airflow through an orifice to spin a turbine.

Decarbonisation and Energy Security (Wave)

Provides emission-free energy to diversify grids and reduce dependency on volatile foreign energy markets.

Coastal Abundance (Wave)

Offers high energy density and continuous power off coasts exposed to major ocean winds, such as Scotland's 6,000+ miles of coastline.

Land Footprint (Wave)

Marine deployments avoid terrestrial land disruption.

Socio-Economic Development (Wave)

Fosters highly skilled employment in marine engineering and manufacturing.

Geographic Concentration (Wave)

Over 80% of harvestable wave energy is in high-latitude temperate regions (30°-60° N/S), leaving equatorial zones unviable.

Intermittency and Grid Constraints (Wave)

Energy varies with weather, making long-term forecasting difficult and necessitating grid reinforcement.

Harsh Operating Conditions (Wave)

High-energy marine environments cause structural fatigue and storm survivability issues, increasing maintenance costs.

Ecological and Spatial Conflicts (Wave)

Mooring lines, devices, and noise disrupt ecosystems, fish migration, habitats, and shipping routes.

Aesthetic and Tourism Impact (Wave)

Coastal installations alter shoreline scenery, potentially affecting the ~$4.6 trillion global marine and coastal tourism industry.

Technological Innovation (WECs)

Engineering resilient Wave Energy Converters generates skilled jobs, though device failure during extreme sea states remains a risk.

Environmental Impact Assessments (EIAs)

Vital for protecting marine biodiversity prior to development, though multi-year data collection can delay commercial deployment.

Marine Spatial Planning (MSP)

Helps avoid conflicts with shipping and fishing while shielding sensitive habitats, requiring high-resolution oceanographic data.

Energy Storage Integration

Battery and auxiliary storage smooth supply fluctuations for grid resilience, though manufacturing and disposal present hazards.

Subsidies and International Collaboration

Public funding accelerates research and tech transfer, though widespread adoption requires local infrastructure and specialised labour.

UK - Limpet Wave Power Station

World's first commercial-scale on-shore wave power generator, located in Isle of Islay, Scotland (1998-2011).

Limpet Wave Power Station Capacity

Featured 2x 250 kW generators powering 40-50 homes at peak or 250-500 homes day-to-day.

Limpet Closure Reasons

Closed down in 2011 due to local grid limitations and ownership changes.

Mutriku Wave Power Plant Location & Opening

Located in the harbour of Mutriku, Spain; opened on July 8, 2011 as the world's first multi-turbine breakwater wave-energy facility.

Mutriku Annual Production

Produces 300,000 kWh annually (powering 250 households) and offsets approx. 600 tonnes of CO2.

Mutriku Working Principle

Waves compress air inside columns forcing it out through an opening to spin a turbine, and draw air back in as waves recede.