Department of Energy Study to Assess Offshore Wind Farm Effects on Radar, Sonar and Communications Systems

Offshore wind energy is a valuable resource that can provide a significant boost to the US renewable energy portfolio. A current constraint to the development of offshore wind farms is the potential for interference to be caused by large wind farms on existing electronic and acoustical equipment for surveillance, navigation and communications. Therefore, the U.S. Department of Energy funded this study as an objective assessment of possible interference to various types of equipment operating in the marine environment where offshore wind farms could be installed.

The interference due to land-based wind farms on radar under certain circumstances has already been widely publicized and studied. The rotation of the turbine blades can give rise to strong Doppler clutter, which can interfere with the operation of existing military, aviation and weather radar systems. In Europe, investigations on the effect of offshore wind farms on marine navigation have been conducted as early as 2004. To date, no comprehensive study of the potential for electromagnetic interference has yet taken place in the US for offshore wind farms. This is due in large part to the lack of any operating offshore wind farms in the US.

For acoustics, while there have been many studies of whether airborne noise generated by wind turbines impacts communities, none was found describing how the sound radiated underwater by offshore installations impacts acoustical equipment. Except in relatively close proximity to the wind farms, a distance that depends on many factors including environmental and those specific to the wind farm itself, the radiated sound pressure levels are comparable to ambient noise levels in coastal waters.

The objective of this project was to conduct a baseline evaluation of electromagnetic and acoustical challenges to sea surface, subsurface and airborne electronic systems presented by offshore wind farms. To accomplish that goal, the following tasks were carried out:

  1. i. Survey electronic systems that can potentially be impacted by large offshore wind farms, and identify impact assessment studies and research and development activities both within and outside the US,
  2. ii. Engage key stakeholders to identify their possible concerns and operating requirements,
  3. iii. Conduct first-principle simulations on the interactions of electromagnetic signals with, and the radiation of underwater acoustic signals from, offshore wind farms to evaluate the effect of such interactions on electronic systems, and
  4. iv. Provide impact assessments, recommend mitigation methods, prioritize future research directions, and disseminate project findings.

Final Report 9/30/13

Webinar 9/4/13

Marine radar movie