Offshore wind energy: The future of renewable sources comes from the sea
November 21, 2024
“Tripling the annual renewable energy capacity over the next six years would be the biggest step the world could take to achieve our global climate goals,” stated Jennifer Layke, Global Energy Director of the World Resources Institute, at the end of COP28 in the United Arab Emirates in December 2023, highlighting the agreement signed by 117 countries.
Although renewable energy (RE) is on track to surpass fossil fuels in global installed capacity, this may not be enough to achieve these goals. According to a recent report by the International Renewable Energy Agency (IRENA), meeting these goals requires increasing RE capacity at a minimum annual rate of 16.4% until 2030. The 14% increase seen in 2023 results in a compound annual growth rate of 10% (2017–2023), which, if maintained, would fall short.
In this scenario, it is essential to continue exploring the development of other unconventional renewable energy sources (URE), among which a new player has emerged: offshore wind energy, which has been growing strongly in recent years.
Offshore energy harnesses the wind generated in open seas. To date, it has been developed using fixed devices installed on the seabed at depths of less than 50 meters. However, recent innovations in floating devices, which are nearing commercial viability, “expand the potential geographic areas compatible with this type of technology, especially in countries lacking an extensive continental shelf, such as our own,” notes the report Technologies for Offshore Energy in Chile: Perspectives and Challenges, prepared by Meric in collaboration with Universidad Austral.
In addition to technological advances, the offshore sector has seen significant geographic expansion. Once concentrated in Europe, it now shows development in Asia (together, these regions represent 99.9% of global capacity). More recently, growth has been observed in North America and Oceania.
“Last year was the second-best year in the history of offshore energy,” states the Global Offshore Wind Report 2024 by the Global Wind Energy Council (GWEC), which explains that 10.8 GW of offshore wind capacity were added to the global grid in 2023. This raised the global total to 75.2 GW, a 24% increase in just 12 months.
The GWEC projects that more than 410 GW will be added between 2024 and 2033. “While the monetary costs of offshore wind energy are still higher than those of other land-based RE sources, significant reductions are projected, driven by economies of scale, technological innovations, and serial manufacturing,” the Meric report explains.
Local Perspectives
A study by the World Bank, cited by Meric, identifies a technical potential of more than 7,100 GW of offshore wind energy in Latin America, with Argentina, Brazil, Chile, and Mexico showing the most promise. Brazil is more advanced, with proposals in its environmental evaluation system exceeding 171 GW; Argentina’s potential is estimated at 1,800 GW, while Chile’s is around 957 GW, of which 14% corresponds to fixed-bottom turbines and 86% to floating ones.
Ana Lía Rojas, Executive Director of the Chilean Association of Renewable Energy and Storage (ACERA), recalls that the first wave of URE development was onshore wind, followed by solar photovoltaics, driven by record cost declines. This, combined with the coal phase-out plan, accelerated investment in renewable technologies, introducing concentrated solar power (CSP), pumped hydro storage, battery storage, and, most recently, offshore wind energy.
“What is the common factor of all these technologies? They can provide a more stable daily load curve, which is required in a system with high penetration of variable RE. In other words, we are now seeking baseload energy, which can be delivered by offshore wind turbines with higher capacity factors than solar and onshore wind,” says Rojas.
Carlos Silva, Associate Researcher at the Center for Energy Transition (CENTRA) at UAI, warns that exploiting offshore wind energy is more challenging than onshore. “The marine environment is highly corrosive, problematic for technologies requiring exposed metal parts and sophisticated systems with moving components. Another significant challenge is the need for foundations (conventional technology) or at least anchors (emerging technology) on the seabed. As ocean depth increases, so do implementation costs.” He predicts, however, that “energy development will continue prioritizing more economical and proven alternatives, such as solar, onshore wind, hydro, bioenergy, and even geothermal, before less accessible technologies like marine energy.”
Nonetheless, Ana Lía Rojas notes that offshore technology is becoming more competitive and “should find a place because it contributes to managing URE variability by providing more stable energy to the system and is generally located near consumption centers.”
Key Advantage
This proximity to consumption centers is one of the greatest advantages. While there is significant onshore wind potential in regions like Antofagasta, Coquimbo, Biobío, and La Araucanía, it decreases when considering territorial restrictions (terrain slope, proximity to urban areas, etc.) and technical constraints (optimal capacity factor and electrical transmission).
In contrast, as a narrow country, Chile’s coastal zones are much closer, enabling “efficient distribution of the generated energy to where it is most needed,” highlights Juan Gari, Regional Manager for Latin America at Deep Wind Offshore, a Norwegian company that has just officially announced plans to install two offshore wind farms in the Gulf of Arauco in the Biobío region. “We can only reveal that we are working on two projects: one with fixed structures, expected to have a capacity of around 900 MW, and another floating project,” he explains.
Geologically and meteorologically, Chile’s coast has surface winds “largely determined by the South Pacific anticyclone, which favors southern winds along the northern and central coasts, and the mid-latitude low-pressure belt generating cyclonic circulation. These winds, which flow uninterrupted over the sea, have greater potential than onshore winds,” Meric’s report details.
An initial estimate suggests the central region could generate approximately 30 gigawatt-hours (GWh) annually with a capacity factor above 40% for a reference 8 MW turbine. The three most promising regions are Valparaíso, Biobío, and Los Ríos.
“Choosing the most suitable locations involves analyzing wind resources and ocean depth. Based on these criteria, southern Chile, particularly Los Lagos and Magallanes, stands out,” says Carlos Silva from CENTRA.
“In our case, we’ve prioritized Biobío for its rich history and potential, with world-class universities, industrial capacity and experience, excellent port infrastructure, and marine management,” explains Gari, adding that Chile “has robust infrastructure, with ports and shipyards capable of supporting the development and implementation of complex technologies like this.”
Roadmap
Gari shares that they chose Chile for their first Latin American project because the country “is committed to achieving carbon neutrality, has a stable and reasonable regulatory framework, and offers an attractive market, allowing companies like ours to invest and plan for the long term.”
However, Ana Lía Rojas notes that, overall, “institutions and the permitting system fall short of the requirements for new renewable investment projects, regardless of their technology. With a new technology that has never been developed or built in Chile, a suitable response from the permitting and authorization system is even less likely.”
The Ministry of Energy told El Mercurio that geographic features and technological advancements have increased the feasibility of offshore projects. “Numerous international consortia have expressed interest,” some of which “have made concrete progress toward development.”
“In light of this, the ministry announced plans this year to draft a roadmap for developing offshore wind energy to close the gaps hindering the implementation of this technology in the country and contribute to the decarbonization and energy transition goals we have set,” the ministry explained.
“This roadmap will evaluate resources, technical potential, and economic viability for advancing this technology in Chile through various technical and economic analyses and modeling. It will also consider gaps in infrastructure, public policy, regulatory, economic, and market conditions,” they elaborated. To advance this document, the ministry is collaborating with the U.S. Department of Energy’s Net Zero World initiative, the World Bank, and experts from the U.S. National Renewable Energy Laboratory (NREL).
Social and Environmental Impacts
The roadmap must also address the social and environmental challenges of offshore development, which vary by location and require adequate study.
In general, the Meric report mentions moderate to high negative impacts, such as mortality and displacement effects on birds and marine mammals, and ecosystem structure alterations. However, a potential positive effect could be the use of installations by marine species, simulating artificial reefs. Another debatable aspect, depending on perspective, is “the mitigation of trawling impacts due to its prohibition in areas near installations for safety reasons,” the study notes. In some countries, this has led to protests from fishers.
There may also be visual impacts, as some find installations along a coastline disruptive to the view. Research found that turbines located more than 40 km offshore are only visible when one focuses on them, at about 29 km they are occasionally noticeable, and at less than 16 km, they become a significant visual focal point.
Another consideration is the multiple uses of maritime space, which involves economic, recreational, and environmental interests, among others.