12 research outputs found

    Marint mikroskopiskt skrÀp lÀngs SkÄnes kust

    No full text
    Marint skrÀp uppmÀrksammas allt mer av vÄra myndigheter, media och av allmÀnheten. Problemets omfattning tas pÄ sÄ stort allvar att marint skrÀp har utsetts som en av elva deskriptorer som anvÀnds för att beskriva god havsmiljö i havsmiljödirektivet (2008/56/EG). Marint skrÀp omfattar enligt direktivet alla storleksfraktioner och alla typer av material som har mÀnskligt ursprung, d.v.s. som Àr antropogena. SkrÀp som förekommer i havet pÄverkar bÄde de djur som lever i havet men ocksÄ mÀnniskor som vistas vid havet och de som fÄr sin inkomst frÄn havet genom exempelvis fiske och turism. Djuren i havet pÄverkas pÄ flera sÀtt av skrÀp, de kan trassla in sig i skrÀpet och skadas eller strypas eller sÄ fÄr de försÀmrade möjligheter att söka föda. Det Àr ocksÄ mÄnga djurarter som Àter upp skrÀp vilket kan leda till en minskad tillvÀxt men ocksÄ att djuret avlider om mÀngden skrÀp Àr för stor. NÄgra av de djurarter som har visat sig Àta upp skrÀp Àr fÄglar, smÄ valar och havssköldpaddor. Vid svenska vÀstkusten har man exempelvis pÄtrÀffat textilfibrer pÄ gÀlarna hos blÄmusslor. Enligt en artikel frÄn 2015 Àr antalet marina djur som hittills har pÄtrÀffats med skrÀp 693 stycken). Ett annat problem med skrÀp Àr att det finns en risk för att vissa skrÀptyper skulle kunna lÀcka ut giftiga kemikalier. Plastprodukter kan exempelvis innehÄlla giftiga additiv som mjukgörare och flamskyddsmedel. Det har ocksÄ visat sig att engÄngsprodukter som omslagspapper till mat kan innehÄlla svÄrnedbrytbara och skadliga polyfluorerade föreningar. VÀgdamm kan innehÄlla en mÀngd olika skadliga Àmnen som polyaromatiska kolvÀten och olika metaller. Polyaromatiska kolvÀten förekommer i fordonsavgaser men ocksÄ i dÀck- och asfaltspartiklar, och metaller kommer frÄn bland annat avgaser och förslitning av dÀck och bilbromsar. This report is only available in Swedish. English summary is available in the report.I den hÀr studien har det provtagits havsvatten pÄ 16 lokaler utanför SkÄnes kust, frÄn Helsingborg i nordvÀst till Bromölla i nordöst, under hösten 2015

    Underwater radiated noise from Point Absorbing Wave Energy Converters : Noise Characteristics and Possible Environmental Effects

    No full text
    The conversion of wave energy into electrical energy has the potential to become a clean and sustainable form of renewable energy conversion. However, like all forms of energy conversion it will inevitably have an impact on the marine environment, although not in the form of emissions of hazardous substances (gases, oils or chemicals associated with anticorrosion). Possible environmental issues associated with wave energy conversion include electromagnetic fields, alteration of sedimentation and hydrologic regimes and underwater radiated noise. Underwater noise has the potential to propagate over long distances and thus have the potential to disturb marine organisms far away from the noise source. There is great variation in the ability to perceive sound between marine organisms, one sound that is clearly audible to one species can be completely inaudible to another. Thus, to be able to determine potential environmental impact from WECs associated with underwater noise, the noise radiated from the WECs must be known. This thesis presents results from studies on the underwater radiated noise from four different full-scale WECs in the Lysekil Wave Power Project. Hydrophones were used to measure the underwater radiated noise from operating point absorbing linear WECs. The main purpose was to study the radiated noise from the operating WECs with emphasis on characteristics such as spectrum levels, Sound Pressure Level (SPL), noise duration and repetition rate. This to be able to determine the origin of the noise and if possible, implement design changes to minimize radiated noise. The results identified two main operational noises (transients with the bulk of the energy in frequencies &lt;1 kHz). The SPL of the radiated noise fluctuated significantly, depending on wave height. Broadband SPLrms of the measurements ranged between ~110 dB and ~140 dB re 1 ”Pa and SPLpeak of specific noises ranges between ~140 and ~180 dB re ”Pa. Audibility was estimated range from 1km to 15 km depending critically on species and on assumptions of propagation loss. The noise is not expected to have any negative effects on behaviour or mask any signals, unless in the vicinity (&lt;150m) of the WECs in significant wave heights. No physical damage, even in close vicinity are expected on either fish or marine mammals. Having the aim to have as little impact on the environment a possible, these studies are important. This way precautions can be implemented early in the technical development of this kind of renewable energy converters. The benefits from the WECs the Lysekil wave power project are believed to outweigh possible environmental impacts due to underwater radiated noise.Vid avhandlingens trycklÀggning upptÀcktes inte att tidpunkt för disputation var fel.</p

    Underwater radiated noise from Point Absorbing Wave Energy Converters : Noise Characteristics and Possible Environmental Effects

    No full text
    The conversion of wave energy into electrical energy has the potential to become a clean and sustainable form of renewable energy conversion. However, like all forms of energy conversion it will inevitably have an impact on the marine environment, although not in the form of emissions of hazardous substances (gases, oils or chemicals associated with anticorrosion). Possible environmental issues associated with wave energy conversion include electromagnetic fields, alteration of sedimentation and hydrologic regimes and underwater radiated noise. Underwater noise has the potential to propagate over long distances and thus have the potential to disturb marine organisms far away from the noise source. There is great variation in the ability to perceive sound between marine organisms, one sound that is clearly audible to one species can be completely inaudible to another. Thus, to be able to determine potential environmental impact from WECs associated with underwater noise, the noise radiated from the WECs must be known. This thesis presents results from studies on the underwater radiated noise from four different full-scale WECs in the Lysekil Wave Power Project. Hydrophones were used to measure the underwater radiated noise from operating point absorbing linear WECs. The main purpose was to study the radiated noise from the operating WECs with emphasis on characteristics such as spectrum levels, Sound Pressure Level (SPL), noise duration and repetition rate. This to be able to determine the origin of the noise and if possible, implement design changes to minimize radiated noise. The results identified two main operational noises (transients with the bulk of the energy in frequencies &lt;1 kHz). The SPL of the radiated noise fluctuated significantly, depending on wave height. Broadband SPLrms of the measurements ranged between ~110 dB and ~140 dB re 1 ”Pa and SPLpeak of specific noises ranges between ~140 and ~180 dB re ”Pa. Audibility was estimated range from 1km to 15 km depending critically on species and on assumptions of propagation loss. The noise is not expected to have any negative effects on behaviour or mask any signals, unless in the vicinity (&lt;150m) of the WECs in significant wave heights. No physical damage, even in close vicinity are expected on either fish or marine mammals. Having the aim to have as little impact on the environment a possible, these studies are important. This way precautions can be implemented early in the technical development of this kind of renewable energy converters. The benefits from the WECs the Lysekil wave power project are believed to outweigh possible environmental impacts due to underwater radiated noise.Vid avhandlingens trycklÀggning upptÀcktes inte att tidpunkt för disputation var fel.</p

    Underwater radiated noise from Point Absorbing Wave Energy Converters : Noise Characteristics and Possible Environmental Effects

    No full text
    The conversion of wave energy into electrical energy has the potential to become a clean and sustainable form of renewable energy conversion. However, like all forms of energy conversion it will inevitably have an impact on the marine environment, although not in the form of emissions of hazardous substances (gases, oils or chemicals associated with anticorrosion). Possible environmental issues associated with wave energy conversion include electromagnetic fields, alteration of sedimentation and hydrologic regimes and underwater radiated noise. Underwater noise has the potential to propagate over long distances and thus have the potential to disturb marine organisms far away from the noise source. There is great variation in the ability to perceive sound between marine organisms, one sound that is clearly audible to one species can be completely inaudible to another. Thus, to be able to determine potential environmental impact from WECs associated with underwater noise, the noise radiated from the WECs must be known. This thesis presents results from studies on the underwater radiated noise from four different full-scale WECs in the Lysekil Wave Power Project. Hydrophones were used to measure the underwater radiated noise from operating point absorbing linear WECs. The main purpose was to study the radiated noise from the operating WECs with emphasis on characteristics such as spectrum levels, Sound Pressure Level (SPL), noise duration and repetition rate. This to be able to determine the origin of the noise and if possible, implement design changes to minimize radiated noise. The results identified two main operational noises (transients with the bulk of the energy in frequencies &lt;1 kHz). The SPL of the radiated noise fluctuated significantly, depending on wave height. Broadband SPLrms of the measurements ranged between ~110 dB and ~140 dB re 1 ”Pa and SPLpeak of specific noises ranges between ~140 and ~180 dB re ”Pa. Audibility was estimated range from 1km to 15 km depending critically on species and on assumptions of propagation loss. The noise is not expected to have any negative effects on behaviour or mask any signals, unless in the vicinity (&lt;150m) of the WECs in significant wave heights. No physical damage, even in close vicinity are expected on either fish or marine mammals. Having the aim to have as little impact on the environment a possible, these studies are important. This way precautions can be implemented early in the technical development of this kind of renewable energy converters. The benefits from the WECs the Lysekil wave power project are believed to outweigh possible environmental impacts due to underwater radiated noise.<p>Vid avhandlingens trycklÀggning upptÀcktes inte att tidpunkt för disputation var fel.</p

    Characteristics of the Operational Noise from Full Scale Wave Energy Converters in the Lysekil Project : Estimation of Potential Environmental Impacts

    No full text
    Wave energy conversion is a clean electric power production technology. During operation there are no emissions in the form of harmful gases. However there are unsolved issues considering environmental impacts such as: electromagnetism; the artificial reef effect and underwater noise. Anthropogenic noise is increasing in the oceans worldwide and wave power will contribute to this sound pollution in the oceans; but to what extent? The main purpose of this study was to examine the noise emitted by a full scale operating Wave Energy Converter (WEC) in the Lysekil project at Uppsala University in Sweden. A minor review of the hearing capabilities of fish and marine mammals is presented to aid in the conclusions of impact from anthropogenic sound. A hydrophone was deployed to the seabed in the Lysekil research site park at distance of 20 and 40 m away from two operational WECs. The measurements were performed in the spring of 2011. The results showed that the main noise was a transient noise with most of its energy in frequencies below 1 kHz. These results indicate that several marine organisms (fish and mammals) will be able to hear the operating WECs of a distance of at least 20 m

    Hydroacoustic measurements of the radiated noise from Wave Energy Converters in the Lysekil project and project WESA

    No full text
    Field measurements of the hydroacoustic noise from Wave Energy Converters (WECs) in the Lysekil project at Uppsala University and the Project WESA (joint effort between Uppsala University (Lead Partner), Ålands Teknikkluster r.f. and University of Turku) are presented. Anthropogenic noise is increasing in the oceans world wide and wave energy conversion may contribute to this noise, but to what extent? The main objective in this study is to examine the noise from full scale operating WECs in the Lysekil and project WESA. Acoustic measurements were made in order to be able to estimate potential environmental impact. Submersible recording devices (SRD) were deployed at 1 m from WECs at a depth of approximately 24 meters. Both WECs are a full scale point absorber with a directly driven linear generator, placed on gravitation foundations at the seabed with a connected buoy at the surface that absorbs energy from the heaving waves. The SRDs used to measure the noise from the WECs, consists of a SM2-recorder from Wildlife Acoustics and hydrophones from High Tech Inc. (HTI 96 MIN and HTI 99 HF). Measurements at in the Lysekil project were carried out in the spring of 2013 and in the project WESA in Jan-Feb of 2012. Preliminary results show that the main operating noise radiated from the WEC are short transients with instant rise time when the translator moves past the stator and when the stator hits the end stop springs of the generator. Most of the power in the noise is between 20 – 1000 Hz.LysekilsprojektetProjekt WES

    Hydroacoustic measurements of the radiated noise from Wave Energy Converters in the Lysekil project and project WESA

    No full text
    Field measurements of the hydroacoustic noise from Wave Energy Converters (WECs) in the Lysekil project at Uppsala University and the Project WESA (joint effort between Uppsala University (Lead Partner), Ålands Teknikkluster r.f. and University of Turku) are presented. Anthropogenic noise is increasing in the oceans world wide and wave energy conversion may contribute to this noise, but to what extent? The main objective in this study is to examine the noise from full scale operating WECs in the Lysekil and project WESA. Acoustic measurements were made in order to be able to estimate potential environmental impact. Submersible recording devices (SRD) were deployed at 1 m from WECs at a depth of approximately 24 meters. Both WECs are a full scale point absorber with a directly driven linear generator, placed on gravitation foundations at the seabed with a connected buoy at the surface that absorbs energy from the heaving waves. The SRDs used to measure the noise from the WECs, consists of a SM2-recorder from Wildlife Acoustics and hydrophones from High Tech Inc. (HTI 96 MIN and HTI 99 HF). Measurements at in the Lysekil project were carried out in the spring of 2013 and in the project WESA in Jan-Feb of 2012. Preliminary results show that the main operating noise radiated from the WEC are short transients with instant rise time when the translator moves past the stator and when the stator hits the end stop springs of the generator. Most of the power in the noise is between 20 – 1000 Hz.LysekilsprojektetProjekt WES

    El canto de las sirenas

    No full text
    Wave energy conversion is a clean electric power production technology. During operation there are no emissions in the form of harmful gases. However there are unsolved issues considering environmental impacts such as: electromagnetism; the artificial reef effect and underwater noise. Anthropogenic noise is increasing in the oceans worldwide and wave power will contribute to this sound pollution in the oceans; but to what extent? The main purpose of this study was to examine the noise emitted by a full scale operating Wave Energy Converter (WEC) in the Lysekil project at Uppsala University in Sweden. A minor review of the hearing capabilities of fish and marine mammals is presented to aid in the conclusions of impact from anthropogenic sound. A hydrophone was deployed to the seabed in the Lysekil research site park at distance of 20 and 40 m away from two operational WECs. The measurements were performed in the spring of 2011. The results showed that the main noise was a transient noise with most of its energy in frequencies below 1 kHz. These results indicate that several marine organisms (fish and mammals) will be able to hear the operating WECs of a distance of at least 20 m

    Wave power--Sustainable energy or environmentally costly? A review with special emphasis on linear wave energy converters

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    Generating electricity from waves is predicted to be a new source of renewable energy conversion expanding significantly, with a global potential in the range of wind and hydropower. Several wave power techniques are on the merge of commercialisation, and thus evoke questions of environmental concern. Conservation matters are to some extent valid independent of technique but we mainly focus on point absorbing linear generators. By giving examples from the Lysekil project, run by Uppsala University and situated on the Swedish west coast, we demonstrate ongoing and future environmental studies to be performed along with technical research and development. We describe general environmental aspects generated by wave power projects; issues also likely to appear in Environmental Impact Assessment studies. Colonisation patterns and biofouling are discussed with particular reference to changes of the seabed and alterations due to new substrates. A purposeful artificial reef design to specially cater for economically important or threatened species is also discussed. Questions related to fish, fishery and marine mammals are other examples of topics where, e.g. no-take zones, marine bioacoustics and electromagnetic fields are important areas. In this review we point out areas in which studies likely will be needed, as ventures out in the oceans also will give ample opportunities for marine environmental research in general and in areas not previously studied. Marine environmental and ecological aspects appear to be unavoidable for application processes and in post-deployment studies concerning renewable energy extraction. Still, all large-scale renewable energy conversion will cause some impact mainly by being area demanding. An early incorporation of multidisciplinary and high quality research might be a key for new ocean-based techniques.Artificial reef Biofouling Environmental impact Offshore renewable energy Sweden Wave energy converters
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