What are the main environmental and social impacts of installing wave energy converters in coastal areas?

1 Types of WECs

There are various types of WECs, depending on the design, location, and mode of operation. Point absorbers are floating devices that capture the energy of waves in all directions and are usually anchored to the seabed or connected to a platform. Attenuators are long and narrow devices that float on the water surface and align with the wave direction, bending and twisting as the waves pass through them to generate electricity. Oscillating water columns are partially submerged structures with a chamber containing air and water, which compresses and decompresses the air as waves enter and exit, driving a turbine. Overtopping devices are reservoirs that collect water from waves that overtop a barrier, which then flows back to the sea through a turbine. Submerged pressure differential devices exploit the pressure difference between wave crest and trough below the water surface using a flexible membrane or piston to move a fluid that powers a generator.

2 Environmental impacts

Installing WECs in coastal areas can have both positive and negative impacts on the environment. Beneficially, it can reduce greenhouse gas emissions and fossil fuel consumption by providing a clean and renewable source of energy, as well as enhance marine biodiversity and habitat by creating artificial reefs and shelter for fish and other organisms. Additionally, it can reduce coastal erosion and flooding by dissipating wave energy and protecting the shorelines. However, it can also alter the wave patterns and currents by absorbing or reflecting wave energy, which can disturb or harm marine wildlife by generating noise, electromagnetic fields, or physical collisions. Furthermore, it can interfere with other marine uses and activities by occupying space, creating hazards, or restricting access.

3 Social impacts

Installing WECs in coastal areas can have both positive and negative impacts on the social and economic aspects of the coastal communities. On one hand, WECs can create jobs and income opportunities by involving local workers in the construction, operation, and maintenance of the technology. It can also support local development and innovation through education, training, and research on wave energy. Furthermore, WECs can improve energy security and resilience by diversifying the energy mix and reducing dependence on imported fuels. On the other hand, WECs can affect the aesthetic and cultural values of the coast by altering the natural scenery, landscape, and soundscape. Additionally, it can cause social conflicts and disputes among different stakeholders over the distribution of costs and benefits. Lastly, it can increase the vulnerability and inequality of coastal communities by creating winners and losers depending on access to wave energy.

4 Mitigation and management strategies

In order to reduce the negative impacts and maximize the positive impacts of installing WECs in coastal areas, comprehensive and participatory environmental and social impact assessments (ESIAs) must be conducted before, during, and after the installation of WECs. This will enable the identification, evaluation, and addressing of potential impacts and trade-offs of WECs. Additionally, best practices and standards for the design, installation, operation, and decommissioning of WECs should be implemented to ensure their safety, efficiency, and compatibility with the marine environment and coastal communities. Furthermore, engaging and involving stakeholders in the planning, decision-making, and monitoring of WECs is necessary to ensure transparency, accountability, legitimacy, acceptance, support, and cooperation.