Tidal Stream vs. Wind Energy: The Value of Cyclic Power When Combined with Short-Term Storage in Hybrid Systems

This study quantifies the technical, economic and environmental performance of hybrid systems that use either a tidal stream or wind turbine, alongside short-term battery storage and back-up oil generators. The systems are designed to partially displace oil generators on the island of Alderney, loca...

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Main Authors: Daniel Coles, Athanasios Angeloudis, Zoe Goss, Jon Miles
Format: Article
Language:English
Published: MDPI AG 2021-02-01
Series:Energies
Subjects:
Online Access:https://www.mdpi.com/1996-1073/14/4/1106
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author Daniel Coles
Athanasios Angeloudis
Zoe Goss
Jon Miles
author_facet Daniel Coles
Athanasios Angeloudis
Zoe Goss
Jon Miles
author_sort Daniel Coles
collection DOAJ
description This study quantifies the technical, economic and environmental performance of hybrid systems that use either a tidal stream or wind turbine, alongside short-term battery storage and back-up oil generators. The systems are designed to partially displace oil generators on the island of Alderney, located in the British Channel Islands. The tidal stream turbine provides four power generation periods per day, every day. This relatively high frequency power cycling limits the use of the oil generators to 1.6 GWh/year. In contrast, low wind resource periods can last for days, forcing the wind hybrid system to rely on the back-up oil generators over long periods, totalling 2.4 GWh/year (50% higher). For this reason the tidal hybrid system spends £0.25 million/year less on fuel by displacing a greater volume of oil, or £6.4 million over a 25 year operating life, assuming a flat cost of oil over this period. The tidal and wind hybrid systems achieve an oil displacement of 78% and 67% respectively (the same as the reduction in carbon emissions). For the wind hybrid system to displace the same amount of oil as the tidal hybrid system, two additional wind turbines are needed. The ability of the battery to store excess turbine energy during high tidal/wind resource periods relies on opportunities to regularly discharge stored energy. The tidal hybrid system achieves this during slack tides. Periods of high wind resource outlast those of high tidal resource, causing the battery to often remain fully charged and excess wind power to be curtailed. Consequently the wind hybrid system curtails 1.9 GWh/year, whilst the tidal turbine curtails 0.2 GWh/year. The ability of the tidal stream turbines to reduce curtailment, fuel costs and carbon emissions may provide a case for implementing them in hybrid systems, if these benefits outweigh their relatively high capital and operating expenditure.
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spelling doaj.art-5c0a84749cbf4f9c8b4f8a35278981722023-12-11T17:40:22ZengMDPI AGEnergies1996-10732021-02-01144110610.3390/en14041106Tidal Stream vs. Wind Energy: The Value of Cyclic Power When Combined with Short-Term Storage in Hybrid SystemsDaniel Coles0Athanasios Angeloudis1Zoe Goss2Jon Miles3School of Engineering, Computing and Mathematics, Faculty of Science and Engineering, University of Plymouth, Plymouth PL4 8AA, UKInstitute for Infrastructure and the Environment, School of Engineering, The University of Edinburgh, Edinburgh EH8 9YL, UKDepartment of Earth Science and Engineering, Imperial College London, London SW7 2AZ, UKSchool of Engineering, Computing and Mathematics, Faculty of Science and Engineering, University of Plymouth, Plymouth PL4 8AA, UKThis study quantifies the technical, economic and environmental performance of hybrid systems that use either a tidal stream or wind turbine, alongside short-term battery storage and back-up oil generators. The systems are designed to partially displace oil generators on the island of Alderney, located in the British Channel Islands. The tidal stream turbine provides four power generation periods per day, every day. This relatively high frequency power cycling limits the use of the oil generators to 1.6 GWh/year. In contrast, low wind resource periods can last for days, forcing the wind hybrid system to rely on the back-up oil generators over long periods, totalling 2.4 GWh/year (50% higher). For this reason the tidal hybrid system spends £0.25 million/year less on fuel by displacing a greater volume of oil, or £6.4 million over a 25 year operating life, assuming a flat cost of oil over this period. The tidal and wind hybrid systems achieve an oil displacement of 78% and 67% respectively (the same as the reduction in carbon emissions). For the wind hybrid system to displace the same amount of oil as the tidal hybrid system, two additional wind turbines are needed. The ability of the battery to store excess turbine energy during high tidal/wind resource periods relies on opportunities to regularly discharge stored energy. The tidal hybrid system achieves this during slack tides. Periods of high wind resource outlast those of high tidal resource, causing the battery to often remain fully charged and excess wind power to be curtailed. Consequently the wind hybrid system curtails 1.9 GWh/year, whilst the tidal turbine curtails 0.2 GWh/year. The ability of the tidal stream turbines to reduce curtailment, fuel costs and carbon emissions may provide a case for implementing them in hybrid systems, if these benefits outweigh their relatively high capital and operating expenditure.https://www.mdpi.com/1996-1073/14/4/1106tidal stream energywind energyhybrid systemintermittencyAlderney
spellingShingle Daniel Coles
Athanasios Angeloudis
Zoe Goss
Jon Miles
Tidal Stream vs. Wind Energy: The Value of Cyclic Power When Combined with Short-Term Storage in Hybrid Systems
Energies
tidal stream energy
wind energy
hybrid system
intermittency
Alderney
title Tidal Stream vs. Wind Energy: The Value of Cyclic Power When Combined with Short-Term Storage in Hybrid Systems
title_full Tidal Stream vs. Wind Energy: The Value of Cyclic Power When Combined with Short-Term Storage in Hybrid Systems
title_fullStr Tidal Stream vs. Wind Energy: The Value of Cyclic Power When Combined with Short-Term Storage in Hybrid Systems
title_full_unstemmed Tidal Stream vs. Wind Energy: The Value of Cyclic Power When Combined with Short-Term Storage in Hybrid Systems
title_short Tidal Stream vs. Wind Energy: The Value of Cyclic Power When Combined with Short-Term Storage in Hybrid Systems
title_sort tidal stream vs wind energy the value of cyclic power when combined with short term storage in hybrid systems
topic tidal stream energy
wind energy
hybrid system
intermittency
Alderney
url https://www.mdpi.com/1996-1073/14/4/1106
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AT athanasiosangeloudis tidalstreamvswindenergythevalueofcyclicpowerwhencombinedwithshorttermstorageinhybridsystems
AT zoegoss tidalstreamvswindenergythevalueofcyclicpowerwhencombinedwithshorttermstorageinhybridsystems
AT jonmiles tidalstreamvswindenergythevalueofcyclicpowerwhencombinedwithshorttermstorageinhybridsystems