Offshore Energy Installations Research Articles

Strategic development of environmental impact assessment decision support tool for offshore energy enables decreased costs, increased utilization, and quality

In the transition to a sustainable energy system, there is an urgent need for expansion of offshore renewable energy installations. To ensure sustainable development also with respect to the marine environment, a variety of decision support tools (DSTs) are currently under development, aiming at potentially increased quality and efficiency for environmental risk assessment (EIA) of planned offshore energy installations. However, the savings potential of a DSTs is to a large extent governed by the timing of the DST development, which in turn is directly dependent on the investment rate over time. A set of development scenarios were evaluated, simulating different degrees of strategic implementation and successful utilization of the DST for offshore energy. Using the situation in Sweden as a case study, we demonstrate that a planned investment can lead to considerably lower total costs for the EIA at a national level, at the same time allowing for improved quality of the EIA in line with the ambitions in both marine spatial planning and existing goals within marine environmental management.

Policy action needed to unlock eDNA potential

Policy action needed to unlock <scp>eDNA</scp> potential

An evaluation of an offshore energy installation for the Black Sea region of Turkey and the effects on a regional decrease in greenhouse gas emissions

AbstractOffshore wind power plants (OWPPs), which are not yet installed in Turkey, are becoming a popular method of energy production around the world because of their environmentally friendly nature. Thus, the installation of OWPPs should be an important agenda item in terms of Turkey's renewable energy policies as a contribution to the global greenhouse gas emission targets. This study proposes a model for installing OWPPs in a suitable part of the Black Sea region of Turkey and simulates the results. The suitable locations for OWPP installation were evaluated according to the technical and geographical conditions of this region and site criteria. Meteorological data from these locations were analyzed in the Wind Atlas Analysis and Application Program (WAsP) to determine the best location. In this study, an OWPP model with a 204.6 MW installed power capacity was proposed for the identified location, which has a wind speed of 8.77 m s−1 and a wind power density of 348 W m−2. Then, an OWPP model and regional energy transmission system was modeled using DigSilent software. The load flow analysis was performed using this model, and the results show that 7616 tons of toxic gas and 1.527 million tons of greenhouse gas could be reduced in the region in a year if the proposed OWPP were put into operation. Thus, with the installation of OWPP, this study shows that annual CO2 emissions can be reduced by 7.63% for the entire Black Sea region. © 2020 Society of Chemical Industry and John Wiley &amp; Sons, Ltd.

Marine stepping-stones: Connectivity of Mytilus edulis populations between offshore energy installations.

Recent papers have suggested that epifaunal organisms use artificial structures as stepping‐stones to spread to areas that are too distant to reach in a single generation. With thousands of artificial structures present in the North Sea, we test the hypothesis that these structures are connected by water currents and act as an interconnected reef. Population genetic structure of the blue mussel, Mytilus edulis, was expected to follow a pattern predicted by a particle tracking model (PTM). Correlation between population genetic differentiation, based on microsatellite markers, and particle exchange was tested. Specimens of M. edulis were found at each location, although the PTM indicated that locations >85 km offshore were isolated from coastal subpopulations. The fixation coefficient F ST correlated with the number of arrivals in the PTM. However, the number of effective migrants per generation as inferred from coalescent simulations did not show a strong correlation with the arriving particles. Isolation by distance analysis showed no increase in isolation with increasing distance and we did not find clear structure among the populations. The marine stepping‐stone effect is obviously important for the distribution of M. edulis in the North Sea and it may influence ecologically comparable species in a similar way. In the absence of artificial shallow hard substrates, M. edulis would be unlikely to survive in offshore North Sea waters.

Improved Detection of the First-Order Region for Direction-Finding HF Radars Using Image Processing Techniques

AbstractFor direction-finding high-frequency (HF) radar systems, the correct separation of backscattered spectral energy due to Bragg resonant waves from that due to more complex double-scattering represents a critical first step toward attaining accurate estimates of surface currents from the range-dependent radar backscatter. Existing methods to identify this “first order” region of the spectra, generally sufficient for lower-frequency radars and low-velocity or low-surface gravity wave conditions, are more likely to fail in higher-frequency systems or locations with more variable current, wave, or noise regimes, leading to elevated velocity errors. An alternative methodology is presented that uses a single and globally relevant smoothing length scale, careful pretreatment of the spectra, and marker-controlled watershed segmentation, an image processing technique, to separate areas of spectral energy due to surface currents from areas of spectral energy due to more complex scattering by the wave field or background noise present. Applied to a number of HF radar datasets with a range of operating frequencies and characteristic issues, the new methodology attains a higher percentage of successful first-order identification, particularly during complex current and wave conditions. As operational radar systems continue to expand to more systematically cover areas of high marine traffic, close approaches to ports and harbors, or offshore energy installations, use of this type of updated methodology will become increasingly important to attain accurate current estimates that serve both research and operational interests.

Artificial Reef Effect in relation to Offshore Renewable Energy Conversion: State of the Art

The rapid worldwide growth of offshore renewable energy production will provide marine organisms with new hard substrate for colonization, thus acting as artificial reefs. The artificial reef effect is important when constructing, for example, scour protections since it can generate an enhanced habitat. Specifically, artificial structures can create increased heterogeneity in the area important for species diversity and density. Offshore energy installations also have the positive side effect as they are a sanctuary area for trawled organisms. Higher survival of fish and bigger fish is an expected outcome that can contribute to a spillover to outer areas. One negative side effect is that invasive species can find new habitats in artificial reefs and thus influence the native habitats and their associated environment negatively. Different scour protections in offshore wind farms can create new habitats compensating for habitat loss by offshore energy installations. These created habitats differ from the lost habitat in species composition substantially. A positive reef effect is dependent on the nature and the location of the reef and the characteristics of the native populations. An increase in surface area of scour protections by using specially designed material can also support the reef effect and its productivity.

Losing control? The privatisation of anti-piracy services in Southeast Asia

Private security companies (PSCs) have emerged in the past 20 years, offering a vast menu of military and security services that were in the past largely the responsibility of government agencies. While PSC operations are often thought to be largely confined to war/conflict zones and failed states in Africa and the Middle East, many PSCs are currently active in Southeast Asia, where they operate within the context of growing economies and comparatively stable polities. The demand for private military and security services in this region comes in part from the maritime sector, where PSCs are today employed to secure ports, vessels and offshore energy installations. Using an analytical framework based on new institutionalism theory, this article focuses on anti-piracy services provided by PSCs in Southeast Asia and examines how the employment of PSCs to secure shipping affects the control of force by states.

Artificial reef effect and fouling impacts on offshore wave power foundations and buoys – a pilot study

Little is known about the effects of offshore energy installations on the marine environment, and further research could assist in minimizing environmental risks as well as in enhancing potential positive effects on the marine environment. While biofouling on marine energy conversion devices on one hand has the potential to be an engineering concern, these structures can also affect biodiversity by functioning as artificial reefs. The Lysekil Project is a test park for wave power located at the Swedish west coast. Here, buoys acting as point absorbers on the surface are connected to generators anchored on concrete foundations on the seabed. In this study we investigated the colonisation of foundations by invertebrates and fish, as well as fouling assemblages on buoys. We examined the influence of surface orientation of the wave power foundations on epibenthic colonisation, and made observations of habitat use by fish and crustaceans during three years of submergence. We also examined fouling assemblages on buoys and calculated the effects of biofouling on the energy absorption of the wave power buoys. On foundations we demonstrated a succession in colonisation over time with a higher degree of coverage on vertical surfaces. Buoys were dominated by the blue mussel Mytilus edulis. Calculations indicated that biofouling have no significant effect in the energy absorption on a buoy working as a point absorber. This study is the first structured investigation on marine organisms associated with wave power devices.