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Utredning av möjligheterna till marin förnybar energi i Öresund

Grahn, Desirée LU (2011) FMI820 20111
Environmental and Energy Systems Studies
Abstract (Swedish)
Syftet med denna studie är att utreda möjligheterna för Öresundskraft AB att utvinna marin förnyelsebar energi från norra Öresund. Studien genomförs i två delar där Öresunds fysikaliska egenskaper samt marina krafttekniker kartläggs i den första för att sedan analysera den möjliga miljöpåverkan från de alternativen som kan vara intressanta i Öresund. De marina energitekniker som studerades var OTEC (Ocean Thermal Energy Conversion), saltkraft, vågkraft, marin strömkraft samt möjligheten till ett frikylaupptag. Vid studien av teknologier eftersträvas att hitta information om optimala förhållanden för varje teknik, i form av våghöjd, strömhastighet etc. Sedan identifieras potentiella miljökonsekvenser för de alternativ som är aktuella för... (More)
Syftet med denna studie är att utreda möjligheterna för Öresundskraft AB att utvinna marin förnyelsebar energi från norra Öresund. Studien genomförs i två delar där Öresunds fysikaliska egenskaper samt marina krafttekniker kartläggs i den första för att sedan analysera den möjliga miljöpåverkan från de alternativen som kan vara intressanta i Öresund. De marina energitekniker som studerades var OTEC (Ocean Thermal Energy Conversion), saltkraft, vågkraft, marin strömkraft samt möjligheten till ett frikylaupptag. Vid studien av teknologier eftersträvas att hitta information om optimala förhållanden för varje teknik, i form av våghöjd, strömhastighet etc. Sedan identifieras potentiella miljökonsekvenser för de alternativ som är aktuella för Öresund. Det fungerar som en förstudie till en framtida miljökonsekvensbeskrivning och är tänkt att i ett tidigt skede uppmärksamma möjliga negativa konsekvenser för miljön.
Studien visade på en potential för utvinningen av energi från marina strömkraftverk samt uttaget av frikyla. Upptaget av frikylan kan göras i både ytvatten och djupvatten. Temperaturen är, under vissa perioder på året, för hög för att kunna användas som primakyla direkt i fjärrkylanätet. Den kan då antingen kylas ytterligare eller användas som kondensorkyla. Frikylan fungerar därmed som en baslast i systemet och kan, trots att temperaturen stundtals är hög, användas och förbättra effektiviteten hos systemet. Analysen av data indikerar att för djup större eller lika med 20 m är den årliga temperaturvariationen densamma. Inga allvarliga miljökonsekvenser kan identifieras för frikyla upptaget men uppmärksamhet bör ges till potentiell förlust av biomassa på grund av uppsug i kylsystemet och effekter på den marina miljön på grund av förändrad temperatur.
Strömhastigheterna i Öresund är bland de högsta i Sverige och ligger normalt mellan 0,15 – 1,2 m/s. Data för de lokaliseringarna som kan tänkas vara intressanta för marina strömkraftverk är begränsade. DMI genomförde mätningar under en längre tid vid en mätstation strax norr om Helsingör och dessa kunde användas för att uppskatta den möjliga energiproduktionen från en marin turbin. Antag en horisontalaxlad turbin med en diameter på 15 och en verkningsgrad på 30 %. Det ger upphov till cirka 132 MWh per år. Det finns ingen allvarlig miljöpåverkan förknippad med marin strömkraft heller men det finns risker för kollisioner och effekter i samband med störande ljud, elektromagnetisk strålning och resuspension av sedimenterade miljögifter.
Även om möjligheterna att utvinna marin förnybar energi är begränsade i nuläget kan ökade elpriser och ytterligare framsteg inom forskningen leda till att en investering kan bli aktuell i framtiden. (Less)
Abstract
The purpose of this study is to determine the possibilities for Öresundskraft AB to derive marine renewable energy from northern Öresund, the sound between Sweden and Denmark. The physical properties of the sound, such as temperature, current speed, wave height, salinity gradients, bathymetry, are researched as well as which technologies are present in the current marine renewable energy market. The production technologies researched were OTEC (Ocean Thermal Energy Conversion), osmotic power, wave power, marine current energy and natural cooling. The different methods for energy production were studied according to which conditions they were optimized for. The suitability for the techniques in Öresund could then be analyzed. As a final... (More)
The purpose of this study is to determine the possibilities for Öresundskraft AB to derive marine renewable energy from northern Öresund, the sound between Sweden and Denmark. The physical properties of the sound, such as temperature, current speed, wave height, salinity gradients, bathymetry, are researched as well as which technologies are present in the current marine renewable energy market. The production technologies researched were OTEC (Ocean Thermal Energy Conversion), osmotic power, wave power, marine current energy and natural cooling. The different methods for energy production were studied according to which conditions they were optimized for. The suitability for the techniques in Öresund could then be analyzed. As a final step, to avoid production methods with a negative impact on the environment and as a pre-study for future environmental impact assessments, the possible environmental impacts were identified.
The study showed a possibility of natural cooling energy for the local district cooling system and marine current energy. The derivation of cooling water can be alternated between surface-adjacent resources and volumes from larger depths. The temperature is, during certain periods of the year, too high to be used as premium cooling in the district cooling system. It can then either be additionally cooled or used as cooling in the condenser. Natural cooling can therefore function as a base load in the system and increase the total efficiency, even though the temperature is too high at times. Data for different depths indicate that the yearly variation of the temperature is the same for all depths beneath 20 m. No severe environmental impacts are associated with this category of marine renewable energy but further research should be focused on the consequences of emission of water at a higher temperature and the risk for loss of biomass in the system.
The currents in Öresund are known for being among the highest in Sweden. Normally they are between 0, 15 – 1, 2 m/s. Unfortunately data to quantify the current speeds are sparse in locations where it is believed to be high. Data was found from The Danish Hydrological Institute for a location north of Helsingör which were used to estimate the possible energy yield. Presumed that production is technically possible for a horizontal turbine, with a diameter of 15 m and an efficiency of 30 % the yield is 132 MWh per year. No severe consequences are probable from a marine current turbine but there is a risk for extensive noise, collision risk, electromagnetic fields and the resuspension of environmental pollutants during dredging.
Even though the possibilities to derive marine renewable energy from the sound are limited today an increasing energy cost combined with advances in development and research it could become viable in the future. (Less)
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author
Grahn, Desirée LU
supervisor
organization
course
FMI820 20111
year
type
H3 - Professional qualifications (4 Years - )
subject
keywords
Marin förnybar energi, OTEC (Ocean Thermal Energy Conversion), vågkraft, marin strömkraft, saltkraft, frikyla, Öresund, temperatur, salthalt, strömhastighet, våghöjd, miljökonsekvensbeskrivning
report number
TFEM--11 / 5054
ISSN
1102-3651
language
Swedish
id
2157137
date added to LUP
2011-09-13 10:04:11
date last changed
2011-09-13 10:04:11
@misc{2157137,
  abstract     = {The purpose of this study is to determine the possibilities for Öresundskraft AB to derive marine renewable energy from northern Öresund, the sound between Sweden and Denmark. The physical properties of the sound, such as temperature, current speed, wave height, salinity gradients, bathymetry, are researched as well as which technologies are present in the current marine renewable energy market. The production technologies researched were OTEC (Ocean Thermal Energy Conversion), osmotic power, wave power, marine current energy and natural cooling. The different methods for energy production were studied according to which conditions they were optimized for. The suitability for the techniques in Öresund could then be analyzed. As a final step, to avoid production methods with a negative impact on the environment and as a pre-study for future environmental impact assessments, the possible environmental impacts were identified.
The study showed a possibility of natural cooling energy for the local district cooling system and marine current energy. The derivation of cooling water can be alternated between surface-adjacent resources and volumes from larger depths. The temperature is, during certain periods of the year, too high to be used as premium cooling in the district cooling system. It can then either be additionally cooled or used as cooling in the condenser. Natural cooling can therefore function as a base load in the system and increase the total efficiency, even though the temperature is too high at times. Data for different depths indicate that the yearly variation of the temperature is the same for all depths beneath 20 m. No severe environmental impacts are associated with this category of marine renewable energy but further research should be focused on the consequences of emission of water at a higher temperature and the risk for loss of biomass in the system.
The currents in Öresund are known for being among the highest in Sweden. Normally they are between 0, 15 – 1, 2 m/s. Unfortunately data to quantify the current speeds are sparse in locations where it is believed to be high. Data was found from The Danish Hydrological Institute for a location north of Helsingör which were used to estimate the possible energy yield. Presumed that production is technically possible for a horizontal turbine, with a diameter of 15 m and an efficiency of 30 % the yield is 132 MWh per year. No severe consequences are probable from a marine current turbine but there is a risk for extensive noise, collision risk, electromagnetic fields and the resuspension of environmental pollutants during dredging.
Even though the possibilities to derive marine renewable energy from the sound are limited today an increasing energy cost combined with advances in development and research it could become viable in the future.},
  author       = {Grahn, Desirée},
  issn         = {1102-3651},
  keyword      = {Marin förnybar energi,OTEC (Ocean Thermal Energy Conversion),vågkraft,marin strömkraft,saltkraft,frikyla,Öresund,temperatur,salthalt,strömhastighet,våghöjd,miljökonsekvensbeskrivning},
  language     = {swe},
  note         = {Student Paper},
  title        = {Utredning av möjligheterna till marin förnybar energi i Öresund},
  year         = {2011},
}