•Temporal characterization of marine energy resources, at varying time scales.•Characterized wave, tidal, and ocean currents, and compared to wind and solar.•Data based exposition of grid benefits ...for wave power at high renewable scenarios.•Data based exposition of higher capacity adequacy and stability for wave power.•Detailed discussion on market implications of grid integration of marine energy.
In this paper, the applicability of marine renewable energy (MRE) for potential grid applications is presented. We show that many of the unique value streams from marine-based electricity generation resources stem from their inherent temporal characteristics, especially when compared to wind and solar. Specifically, in this work, we evaluate the timing value for three types of MRE resources: (a) tidal, (b) wave, and (c) ocean currents. First, through a suite of novel metrics, such as resource availability, persistence, and versatility, we evaluate the temporal value characteristics of these resources. Second, through a more grid-oriented numerical study, we comment on the potential ramifications of those temporal characteristics in context of energy balancing and effective load carrying capability for one marine-based resource i.e., wave. Finally, we further our understanding of the relative advantages that may be leveraged by operating wave-based generation in tandem with more established renewable resources, such as wind and solar. Our results indicate that compared to wind and solar, MRE resources are consistently more available and persistent on an hourly level throughout an entire year of operation. In addition, wave resources are also seen to reduce the balancing requirements within the power system. Our work focuses on sites specific to the United States (US) and a parallel study for a location in Great Britain (GB). Results are found to be consistent for sites in both the US and GB, implying that the grid benefits discussed in this work could apply to a number of locations globally.
This work investigates potential cost reduction trajectories of three emerging offshore renewable energy technologies (floating offshore wind, tidal stream, and wave) with respect to meeting ...ambitious cost targets set out in the Strategic Energy Technology Implementation Plans (SET-Plans) for Offshore Wind and Ocean Energy. A methodology is presented which calculates target costs for current early-stage devices, starting from the 2030 SET-Plan levelised cost targets. Component-based experience curves have been applied as part of the methodology, characterised through the comparative maturity level of each technology-specific cost centre. The resultant early-stage target costs are then compared with actual costs for current devices to highlight where further cost reduction is still required. It has been found that innovation and development requirements to reach these targets vary greatly between different technologies, based on their current level of technological maturity. Future funding calls and programmes should be designed with these variables in mind to support innovative developments in offshore renewables. The method presented in this paper has been applied to publicly available cost data for emerging renewable technologies and is fully adaptable to calculate the innovation requirements for specific early-stage renewable energy devices.
•Temporal characterisation of wave and tidal resource availability for Great Britain.•Ten metrics used to explore temporal characterisation and supply-demand matching.•Generation profiles with marine ...energy consistently outperform those without.•Correlation with load is not a suitable metric to establish supply-demand alignment.•Detailed discussion of potential GB power system benefits from marine energy.
Wave and tidal energy have the potential to provide benefits to power systems with high proportions of stochastic renewable generation. This is particularly applicable in combination with wind and solar photovoltaics, as the offsetting of these renewable resources results in more reliable renewable generation. This study utilises ten metrics to quantify the temporal complementarity and supply-demand balancing requirements of the energy mix in Great Britain, to investigate the potential magnitude of these system benefits. Wave and tidal generation profiles are created using historical resource data and hydrodynamic models. The results show that the inclusion of wave and tidal generation creates a renewable energy mix which is more available under multiple conditions: throughout a year of operation; at times of peak demand; for multiple consecutive hourly time periods; and at times when wind and solar generation are not available. Three regional case studies also show that the inclusion of marine energy allows for improved regional supply-demand matching, reducing instances of energy shortage and excess and potentially relieving transmission congestion at particularly constrained locations within GB. Finally, the implications of these findings are discussed in terms of GB wholesale market operation, system balancing and system security.
The transition to low-carbon energy systems is a complex process that implies radical technological changes, greenhouse gas emission reductions, and benefits to the local economies yet, also ...significant investment, a need for capacity building, strengthening supply chains and supporting legal frameworks. Consequently, the choice of renewable energy technologies should be based on a comprehensive assessment addressing the different dimensions that are affected. Clean energy technologies are traditionally evaluated on the basis of their techno-economic performance. Such an approach penalises emerging energy technologies that are generally more capital-intensive given their innovation requirement and the lack of support mechanisms facilitating their industrial roll-out. In this paper, a multi-criteria evaluation framework is proposed encompassing three important broad dimensions: techno-economics, environment and socio-economics. The applicability and flexibility of the proposed evaluation framework are demonstrated on different case studies. First, the hypothetical deployment of a floating offshore wind farm both in Scotland and Portugal is evaluated. Later, the proposed framework is used to evaluate the deployments of wave energy devices in the same two locations. The results show that this multi-criteria approach provides a more holistic overview of the performance and implications of renewable energy technologies, particularly emerging ones, and can better support decision- and policy-making in the medium- and long-term. Furthermore, the framework can be used by researchers, investors, developers and/or analysts to assess energy planning alternatives.
•Techno-economic performance of renewable technologies is traditionally assessed.•An alternative multi-criteria evaluation framework is proposed.•A comprehensive assessment including economics, environment and socio-economics.•The proposed framework is suitable to assess emerging offshore technologies.•Offshore technologies will be instrumental for low-carbon energy systems.
The new Energy System Model for Remote Communities (EnerSyM-RC) is implemented to quantify impacts from adopting tidal stream power alongside solar PV, offshore wind and energy storage in the Isle of ...Wight energy system. Based on scenarios with gross renewable energy generation matched to projected annual demand (equivalent to 136 MW mean power), installing 150 MW of solar PV, 150 MW of offshore wind, and 120 MW of tidal stream capacity enhances supply–demand balancing whilst also reducing the magnitude of maximum power surplus, both by 25% relative to the best performing solar+wind system. Tidal stream adoption also reduces total land/sea space by 33%. The economic viability of tidal stream capacity adoption is heavily dependent on the price of reserve energy; when the reserve energy price exceeds the average 2022 forward delivery contracts price (250 £/MWh), adopting tidal stream capacity reduces the levelised cost of whole-system energy relative to solar+wind systems. This tipping point, at which the whole-system levelised cost of energy is 92 £/MWh, occurs when the premium on tidal stream energy is outweighed by savings on reserve energy. In general these system benefits arising from tidal stream adoption are consistent over a range of different demand profiles, and in cases where gross annual renewable supply is oversized relative to demand.
•EnerSyM-RC model quantifies impacts of tidal stream (TS) on energy system security.•Adoption of TS reduces reliance on reserve supply by 26%.•TS limits maximum power surplus magnitude by 24%.•TS reduces the total land/sea space used by renewables by 33%.•TS minimises system LCoE to 92 £/MWh, with 250 £/MWh reserve energy price.
It is understood that electricity generation from the waves and tides can be temporally and spatially offset from other, more established variable renewables, such as wind and solar. However, it is ...less well understood how this offsetting can impact on power system operation. A novel modelling framework has been developed to quantify the potential benefit of including higher proportions of ocean energy within large-scale electricity systems. Economic dispatch modelling is utilised to model hourly supply–demand matching for a range of sensitivity runs, adjusting the proportion of ocean energy within the generation mix. The framework is applied to a 2030 case study of the power system of Great Britain, testing installed wave or tidal stream capacities ranging from 100 MW to 10 GW. For all sensitivity runs it has been found that ocean energy increases renewable dispatch, reduces dispatch costs, reduces generation required from fossil fuels, reduces system carbon emissions, reduces price volatility, and captures higher market prices. For example, including 1 GW of wave displaces up to £137M and 128 ktCO2 over the year of dispatch modelled. Similarly, 1 GW of tidal stream displaces up to £95M and 87 ktCO2. When including 10 GW of ocean energy, dispatch costs reduce by up to 7% and carbon emissions reduce by up to 29%. This analysis has included the development and publication of open source models of the Great British power system.
•Modelling framework developed to quantify power system benefits from ocean energy.•Economic dispatch modelling used to represent power system supply–demand balancing.•Hourly generation timeseries created to represent wave and tidal stream resource.•Sensitivity analyses used to vary proportion of ocean energy within power system.•GB case study quantifies economic and environmental benefits from ocean energy.
Wave energy has a large global resource and thus a great potential to contribute to low-carbon energy systems. This study quantifies the environmental impacts of a 10 MW array of 28 point-absorber ...wave energy converters, by means of a process-based life cycle assessment (LCA). Midpoint and Cumulative Energy Demand LCA results are presented over 19 impact categories, representing impacts encompassing human health, ecosystems and resource availability. Three scenarios are undertaken to represent the use phase of the array, identified as a particularly uncertain input, with very little long-term operation of wave energy arrays available to validate assumptions. The resultant global warming potential of the array ranges from 25.1 to 46.0 gCO2e/kWh over a 95% confidence interval, 23–43 times lower than conventional fossil fuel electricity generation. The Energy Payback Time of the array ranges between 2.6 and 5.2 years. LCA results are found to be particularly sensitive to annual energy production across all impact categories, and to assumptions associated with the frequency of marine operations over a number of categories quantifying the production of greenhouse gases. This LCA has been undertaken at an early stage in the WEC product development and will inform innovative research focused on further reducing the environmental impacts of electricity generation.
•Evaluation of the environmental impacts for a 10 MW array of wave energy converters.•Inclusion of three scenarios to investigate impacts of use phase marine operations.•Monte Carlo uncertainty analysis presents results over 95% confidence intervals.•Environmental hotspots are identified to inform future design considerations.
Abstract
There is about to be an abrupt step-change in the use of coastal seas around the globe, specifically by the addition of large-scale offshore renewable energy (ORE) developments to combat ...climate change. Developing this sustainable energy supply will require trade-offs between both direct and indirect environmental effects, as well as spatial conflicts with marine uses like shipping, fishing, and recreation. However, the nexus between drivers, such as changes in the bio-physical environment from the introduction of structures and extraction of energy, and the consequent impacts on ecosystem services delivery and natural capital assets is poorly understood and rarely considered through a whole ecosystem perspective. Future marine planning needs to assess these changes as part of national policy level assessments but also to inform practitioners about the benefits and trade-offs between different uses of natural resources when making decisions to balance environmental and energy sustainability and socio-economic impacts. To address this shortfall, we propose an ecosystem-based natural capital evaluation framework that builds on a dynamic Bayesian modelling approach which accounts for the multiplicity of interactions between physical (e.g. bottom temperature), biological (e.g. net primary production) indicators and anthropogenic marine use (i.e. fishing) and their changes across space and over time. The proposed assessment framework measures ecosystem change, changes in ecosystem goods and services and changes in socio-economic value in response to ORE deployment scenarios as well as climate change, to provide objective information for decision processes seeking to integrate new uses into our marine ecosystems. Such a framework has the potential of exploring the likely outcomes in the same metrics (both ecological and socio-economic) from alternative management and climate scenarios, such that objective judgements and decisions can be made, as to how to balance the benefits and trade-offs between a range of marine uses to deliver long-term environmental sustainability, economic benefits, and social welfare.
This work has investigated the premise that utilising zonal pricing for congestion management within Great Britain (GB) with Scotland as a separate price zone than the rest of GB could disincentivise ...investment in wind generation within areas of the highest wind resource. Computational modelling has shown consistently less installed wind capacity in Scotland in scenarios representing zonal pricing compared with scenarios representing the current GB system. This suggests that in the long term implementing zonal pricing within GB could negatively impact on the investment of low carbon generation in locations with the best renewable resource, which would be the most cost-effective method of meeting carbon reduction targets under the UK Levy Control Framework The interaction between investing in low carbon generation within multiple price zones and the subsidy framework including a feed-in tariff with Contracts for Difference (CfDs) is a key focus of this work. Multiple scenarios are developed following a discussion of form that the CfD scheme could take in a two-zone GB. These comprise of a base case scenario representing current electricity trading within GB, a scenario in which the current competitive auction system does not change and CfD strike prices remain GB-wide and a scenario in which locational strike prices are introduced. Computational modelling has taken the form of a two-node linear solver to introduce and discuss the potential impacts of two price zones in GB on investment in low carbon generation and the Scottish Electricity Dispatch Model (SEDM), an eighteen node investment and dispatch model with greater spatial and temporal complexity and thus a more accurate representation of the GB system. The modelling methodology includes representing a range of objective functions, which has been shown to significantly affect the zonal results. Cases have also been revealed in which the SRMC iteration process did not converge for the two zone solver, highlighting the potential issues involved with modelling a subsidy framework like the CfD mechanism within multiple price zones.
The development of new renewable energy technologies is generally perceived as a critical factor in the fight against climate change. However, significant difficulties arise when estimating the ...future performance and costs of nascent technologies such as wave energy. Robust methods to estimate the commercial costs that emerging technologies may reach in the future are needed to inform decision-making. The aim of this paper is to increase the clarity, consistency, and utility of future cost estimates for emerging wave energy technologies. It proposes a novel three-step method: (1) using a combination of existing bottom-up and top-down approaches to derive the current cost breakdown; (2) assigning uncertainty ranges, depending on the estimation reliability then used, to derive the first-of-a-kind cost of the commercial technology; and (3) applying component-based learning rates to produce the LCOE of a mature technology using the upper bound from (2) to account for optimism bias. This novel method counters the human propensity toward over-optimism. Compared with state-of-the-art direct estimation approaches, it provides a tool that can be used to explore uncertainties and focus attention on the accuracy of cost estimates and potential learning from the early stage of technology development. Moreover, this approach delivers useful information to identify remaining technology challenges, concentrate innovation efforts, and collect evidence through testing activities.
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