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Variable renewable generation and load fluctuations induce significant balancing cost in power system operation. To overcome this issue, this paper proposes a control architecture that leverages inherent regulation capabilities of wind turbines to minimize the system‐wide balancing costs. Instead of handling wind power fluctuations via power filtering algorithms that are agnostic to system‐wide power imbalance, this paper aims to optimize the wind power generation profile from system perspective. In the proposed method, wind turbines are modelled as semi‐dispatchable units, where the dispatch command is dynamically generated at every automatic generation control cycle by considering mileage payments as an indicator of system‐wide imbalance. As a result, local resources of wind turbines are optimally leveraged in real‐time to mitigate system‐wide power imbalances. The proposed strategy and state‐of‐the‐art techniques are compared in comprehensive high‐fidelity case studies. Our simulation results demonstrate that the proposed system‐aware regulation scheme can alleviate system balancing costs without investments into energy storage systems.

Microgrids are quickly becoming a great success for the future of electricity. The notion of the microgrid combines several microsources without interfering with the functioning of the larger utility grid. The DC and AC networks of this hybrid Microgrid are powered by photovoltaic and wind generators. Both AC and DC Microgrids may couple with energy storage devices. A microgrid powered by a combination of renewable energy sources, such as wind and solar, is shown and controlled in this project. The wind energy conversion machine is a doubly fed induction generator (DFIG), and it is coupled to a battery bank through a DC bus. Solar power is efficiently converted utilising a DC-DC boost converter from a solar photovoltaic (PV) array and then evacuated at the common DC bus of DFIG. With the line side converter's droop characteristics implemented, voltage and frequency may be regulated using an indirect vector control. A battery's energy level is monitored, and the frequency set point is adjusted accordingly to prevent excessive charging or discharging. When wind power is not available, the system can still function. Maximum power point tracking (MPPT) is a feature of the control algorithm used by both wind and solar energy blocks. All conceivable operational scenarios have been accounted for in the system's design, making it fully autonomous. An external power supply is included into the system and may be used to charge the batteries whenever needed. The feasibility of wind and solar energy, imbalanced and nonlinear loads, and a depleted battery are only some of the scenarios simulated in this paper, along with the corresponding simulation findings.

The purported social, economic and environmental benefits are resulting in increased wind penetration in existing power systems. However, due to inherent uncertainty of wind energy, thermal generators are expected to maintain security and reliability of power systems. Further, in view of the huge investments in existing power plant installations, thermal power may not be completely replaced by renewable energy sources such as wind power in near future. Therefore, reduction in capacity factor of the existing thermal generators due to wind integration is a major policy concern. This aspect must be juxtaposed with benefits of wind integration such as cost savings and emission reduction. The current study introduces a Capacity Factor Violation Index (CFVI) to evaluate the impact of wind integration on capacity factor of thermal generators. A distance metric comprising of cost savings, emission reduction, network losses and CFVI is proposed based on Compromise Programming (CP). Sensitivity analysis is performed by varying the wind penetration and turbine ratings and the impact on the distance metric is investigated. The proposed methodology is comprehensively demonstrated in eleven popular test power systems.

Wind energy has become increasingly important for meeting Europe's energy needs. While onshore wind expansion faces public acceptance problems, for offshore wind the European Commission has introduced ambitious goals to increase capacity from 15GW to 300GW in 2050. Incorporating more offshore wind electricity into the power grid may offer a more widely accepted way to satisfy Europe's energy demand. In particular, the North Sea region has large potential for offshore wind generation. However, to fully exploit the wind potential in the North Sea, the grid integration of offshore wind and floating wind turbines are vital, especially when onshore wind capacity and onshore grid expansion are constrained. For the grid integration, a meshed offshore grid can offer a viable alternative to the standard direct connection of offshore wind parks to the nearest point on land combined with point-to-point HVDC connections. In this paper, we investigate the benefits of having a meshed offshore grid in the North Sea and considering floating wind besides fixed-bottom wind installations. In our analysis, we look at eight different scenarios, where onshore wind potentials and onshore line expansion are limited, to explore the effects of low public acceptance. Our results demonstrate that the presence of an offshore grid can reduce total system costs by up to 2.6 bn Euro/a. In the scenarios with an offshore meshed grid, ~8% more offshore wind capacities are built compared to the scenarios without a meshed grid. Furthermore, the analysis shows that if onshore wind potentials are restricted, floating wind turbines play a key role and compensate for lacking onshore wind capacities.

There has been a growing concern to supply power to customers mainly when their processes are based on susceptible loads. In such a scenario, power quality becomes extremely relevant. This study investigates the power flow operation in a three-phase unbalanced radial distribution network for dynamic load intervals, in order to regulate the wind production. This paper presents the power loss and voltage improvement benefits for wind integration in a three-phase unbalanced radial distribution network (URDN) by choosing the best location and the right amount of penetration of wind generation. The combination of constant power, constant current, and constant impedance load models are incorporated into the power flow method of the backward forward sweep. The IEEE 37-bus URDN is contemplated to test the proposed method.

This paper investigates the combination of dynamic line rating (DLR) and FACTS to mitigate the network congestions due to wind integration. A novel co-allocation model is proposed to select the optimal transmission lines for the installations of DLR and FACTS. The formulation explicitly considers the forecast uncertainties of DLR and wind power with the adoption of chance constraints to limit the operational uncertainty of the network. To deal with the computational intractability of the original allocation model, a reformulation and decomposition methodology is developed. The case study on the IEEE 118-bus system demonstrates the benefit of the combination of DLR and FACTS in congestion mitigation and the effectiveness of the proposed allocation model.

This paper proposes a methodology for optimal cable replacement based on utility financial benefits that are calculated by considering the entire network in the planning period. The overall problem is set within a sequential Monte Carlo simulation framework and uses novel reliability modelling of ageing distribution cable using the ‘IEC-Arrhenius-Weibull’ model. Optimal cable replacement schemes are developed by considering the connection of new wind sources and network reconfiguration to reduce cable ageing and defer its replacement. The core concepts of the proposed methodology are two new mixed-integer non-linear optimization models. The first optimizes the connection of new wind sources by minimizing the connection and reinforcement costs, as well as minimizing the cost of the cable thermal-loss-of-lives in the planning period. In the operations stage, the network is optimally reconfigured to minimize the cost of losses, the thermal-loss-of-life of cable, and reliability. Both optimization models are applicable to radially operated medium voltage networks that are backfed from several normally open points. The final outputs are proposed cable ranking lists for replacement and reliability and cost metrics.

Due to environmental concerns and to meet the increasing load growth, the renewables penetration, mainly wind, is increasing rapidly. This leads to changes in system configuration and load flow. Due to this the dynamic interaction due to converters increases, and this amplifies the low frequency oscillations (LFOs) issues in the grid. The study presented analyzed the impact of doubly fed induction generator (DFIG) wind farms location on the small signal stability of the system. The analysis is performed using well established modal analysis technique. The study is carried out on the IEEE benchmark 39-bus test system. The investigations performed can be utilised for the initial phases of grid planning to be integrated with DFIG wind farms.

This case study highlights the challenges, innovations and recommendations of wind-diesel integration projects in remote Alaska through the lens of the Chaninik Wind Group. Although energy access and affordability is extremely difficult in remote areas, renewable energy technologies prove valuable in reducing the cost of energy for consumers.

In this paper, we present an optimal capacity decision model for energy storage systems (ESSs) in combined operation with wind energy in power systems. We use a two-stage stochastic programming approach to take into account both wind and load uncertainties. The planning problem is formulated as an AC optimal power flow (OPF) model with the objective of minimizing ESS installation cost and system operation cost. Stochastic wind and load inputs for the model are generated from historical data using clustering technique. The model is tested on the IEEE 39-bus system.

System integrity protection schemes (SIPS) are widely applied to power networks to ensure their operating security. This is particularly important when a network is operating close to its limits. As a result of green initiatives, SIPS are being applied on many national networks to accommodate new generation interconnections and especially wind farms. However, this results in an increased probability of undesirable interactions between multiple SIPS and raises concerns about SIPS reliability. A procedure to assess the risk of SIPS maloperations and undesirable interactions between different SIPS on the same or neighboring systems is proposed in this paper. A numerical illustration of this method is presented using the PJM 5-bus system to demonstrate the performance of various SIPS solutions that involve advanced information communication technologies and wide area monitoring, protection, and control. The risk assessment method can be used to integrate the impact of SIPS into a SIPS-aided transmission expansion plan. A new type of SIPS with adaptive protection logics that adjusts to the increasingly variable system conditions and the performance of other protection schemes is proposed to manage the induced risk.

In power systems today, considerable developments are being made in the energy transition from centralized fossil fuels to renewable distributed generation (DG) sources. However, this ongoing progress has presented several challenges to the operation and planning of distribution systems due to the variability of intermittent renewable generation. Demand response (DR) is widely regarded as a feasible tool to provide a seamless transition by altering the load profiles according to the intermittent generation profile. However, the resultant volatile power flows can be taxing for network capacity. This paper offers a framework from the distribution system operator's perspective for the optimal utilization of DR between DG curtailment mitigation and network management. The application of the developed framework to a generic Finnish distribution system demonstrates that the benefits of DR should be envisioned for network management as long as the wind curtailment rate is below a certain level. This means that, beyond the threshold energy curtailment rate, the distribution system operator would be more economically efficient by making network reinforcements.

Racing sailboats are becoming more and more complex systems, especially with the increasing interest in total 3D attitude control. In such competitive context, realistic simulation appears as a key point for new developments. This paper presents AVS, a framework dedicated to sailboat simulation, integrating both requirements of a generic simulation framework and domain-specific aspects. The AVS framework provides a collection of models and tools to design, generate and evaluate racing sailboat simulations. Tools are also provided to integrate heterogeneous wind sources in simulation. Thanks to component-based approach, different simulation scenarios can be considered by adding or configuring components. Two simulation examples illustrate the AVS framework agility to evaluate sailing boat control law.

This chapter describes the experience in the analysis of wind and solar integration in largescale power grids with complex dynamics and operating characteristics. It presents the methods for interpreting and understanding the impact of distributed renewable energy resources on global oscillatory behavior and discusses the processes involved in development and testing of tools for studying wind and hydro generation. The chapter also discusses the issues of network reactive control performance and tuning, inertia reduction, generation commitment, grid stability, and power system frequency response in detail. Steady‐state eigenvalue analyses and detailed step‐by‐step simulations are used for assessing issues regarding wind and solar integration. The advent of modern, inverter‐based wind and solar farms offers a direct means for controlling system voltage. Specifically, the wind farms in the south systems are expected to provide local voltage support.

Flexibility in plug-in electric vehicle (PEV) charging can reduce the ancillary cost effects of wind variability and uncertainty on electric power systems. In this paper, we study these benefits of PEV charging, demonstrating that controlled PEV charging can reduce costs associated with wind uncertainty and variability. Interestingly, we show that the system does not require complete control of PEV-charging loads to mitigate the negative cost impacts of wind variability and uncertainty. Rather, PEV owners giving the system a two-hour window of flexibility in which to recharge their vehicles provides much of the benefits that giving full charging control does.

With competitive electricity market operation, open access to the transmission and distribution network is essential for transparent and efficient market operation. Like transmission pricing, distribution network pricing must also be transparent and must include tile variations based on the change in the operating state of the system, integration of renewable sources and must be real time. In this paper, a distribution system nodal pricing scheme is proposed for radial distribution system with integration of wind power in the system. The main objective of the paper is: (i) an optimal power flow based approach for determination of nodal prices for distribution system, (ii) impact of wind generation on nodal prices. The results have been obtained for IEEE 33 bus test system.Keywords: Distribution system, electricity market; nodal prices, wind power integration

In this paper a probabilistic multi-objective Reactive Power Planning (RPP) framework is presented for power systems with high penetration of wind energy. Investment cost of reactive resources, total generation costs, voltage stability index and total voltage deviation of buses are considered as objective functions. Here effects of different strategies for controlling reactive power of wind turbines on reactive power planning are investigated. To cope with load and wind speed uncertainties a Two Point Estimation Method (2PEM) is utilized. Non-dominated sorting Genetic Algorithm II (NSGA II) is used to solve the problem. The proposed method is implemented on IEEE 24-bus test system to verify its capabilities.

The virtual synchronous machine (VSM) control strategy has been demonstrated as an effective method to improve system stability in recent research. It mimics the dynamic characteristics of traditional synchronous generator (SG), and therefore can provide frequency support under disturbances. However, the integration of multiple VSMs may deteriorate the power system performance by participating in the system oscillations due to their emulations of SG’s swing equation. Therefore this paper investigates the system performance with multiple VSMs integrated. Besides, a supplementary controller is designed to enhance system stability. A modified two-area system is utilized to validate the effectiveness of the designed controller in Real-Time Digital Simulator (RTDS) platform.

A large number of advantages are offered by multi level inverters and hence a number of topologies are proposed over the years. There has been an evolution of new topologies with reduced number of switching devices. Not a single topology is enough for all the applications, so these topologies are developed with orientation based upon the application. Some topologies suites one application but do not suite well to the other application. The paper presents a comparative modelling analysis of a number of multilevel inverter topologies with reduced device count with the purpose of proposing the better options out of reduced device count topologies for economic optimization of grid interface inverter.

As the offshore wind installations are moving further from shore, the transmission distance also increases. Synthesize the cost of construction and maintenance, as well as the technical maturity, grid-connection via AC network will still be a preferred power delivery method for offshore wind power projects in the near future. However, according to the “8•9” blackout in the UK, there is sub-synchronous oscillation (SSO) risk in the AC network connected offshore wind projects, which was attributed to the mismatch between the power electronic source and the power grid. In this article, both eigenvalue analysis and time-domain simulation method are used to evaluate the operating SSO stability of grid integration of large scale offshore wind power. It suggests that transmission system via long distance cables naturally forms a weak AC network, and the SSO characteristics of AC grid connected offshore wind farm is closely related to the wind turbine parameters, offshore distance and the active power output level. At last, the principle of parameter configuration in offshore wind turbines is proposed based on different offshore distances.

Thermal storage capability of residential heating loads can enhance power system flexibility and can potentially facilitate grid integration of variable renewable generation. This paper presents a detailed assessment of the wind integration potential of both active and passive residential thermal storage using the Building-to-Grid (B2G) model. The B2G model integrates buildings’ thermal dynamics and end-use constraints within a reserve-constrained unit commitment tool. The presented case studies evaluate the impact of various factors on the wind integration potential of residential thermal storage. These factors include storage capability of active and passive thermal storage, wind penetration levels, and participation of heating loads in various categories of system reserve. The results depict that utilisation of residential thermal storage can facilitate wind curtailment reduction. However, analysis of the results highlights that the curtailment reduction potential of thermal storage is constrained during large wind curtailment events. The start-up costs reduction potential of thermal storage becomes more important with increasing wind penetration levels. It was also observed that for the considered test system, participation of heating loads in over-frequency reserves is more important than under-frequency reserves in terms of wind curtailment reduction.

The penetration of renewable energy sources, particularly wind energy, into power systems has been rapidly increasing in recent years. However, the integration of wind power has posed many challenges for power system operation. For instance, this type of energy source is relatively variable and unpredictable. The installation of this renewable source might require the grid to transmit power at full capacity and some transmission lines could become congested. As a result, in some operating conditions, wind power could be curtailed, which will drive up costs for system operators. One of the actions that can be taken to support the integration of the wind is using energy storage systems. In this paper, a multiperiod ac optimal power flow problem with battery energy storages (BESs) is formulated and sets of candidate buses for BES installation are identified based on an economic criterion. Tests are carried out on IEEE 14-bus and IEEE 118-bus systems to assess the robustness of storage location on system operation.

This paper studies centralized and distributed schemes for the coordinationof power injection in an HVDC grid connected to large wind generation.This coordination of power injection aims to keep th ...

A critical step in stochastic optimization models of power system analysis is to select a set of appropriate scenarios and significant numbers of scenario generation methods exist in the literature. This paper develops a clustering based scenario generation method, which aims to improve the performance of existing scenario generation techniques by grouping a set of correlated wind sites into clusters according to their cross-correlations. Copula based models are utilized to model spatiotemporal correlations and the Gibbs sampling is then used to generate scenarios for day-ahead markets. Our results show that the generated scenarios based on clustered wind sites outperform existing approaches in terms of reliability and sharpness and can reduce the total computational time for scenario generation and reduction significantly. The clustering-based framework can therefore provide a better support for real-world market simulations with high wind penetration.

Along with development of remote wind farms, offshore transmission networks become an integral part of wider transmission system. In this paper, an offshore transmission network planning (TNP) model is proposed for large-scale wind integration. The proposed approach allows system planners to evaluate the economic and technical feasibility of a range of potential network and non-network options considering a variety of uncertainties. The framework can be divided into one high-level planning problem determining a suitable type of power transmission technology and network routine over given planning horizon, and several low-level problems that examine the feasibility and optimality of the solution from the high-level problem considering different remedial action schemes, which is expected to reduce the need for adding new lines considering a broad range of uncertainty during system operation. Numerical examples on an IEEE 14-bus test system and an Australian regional transmission grid illustrate the performance of the proposed TNP model.

In this paper, a two-stage stochastic unit commitment (UC) model considering flexible scheduling of demand response (DR) is proposed. In the proposed UC model, the DR resources can be scheduled: (1) in the first stage, as resources on a day-ahead basis to integrate the predicted wind fluctuation with lower uncertainty, (2) in the second stage, as resources on an intra-day basis to compensate for the deviation among multiple wind power scenarios considering the coupling relationship of DR on available time and capacity. Simulation results on the Pennsylvania-New Jersey-Maryland (PJM) 5-bus system and IEEE 118-bus system indicate that the proposed model can maximize the DR value with lower cost. Moreover, different types of DR resources may vary in the contract costs (capacity costs), the responsive costs (energy costs), the time of advance notice, and the minimum on-site hours. The responsive cost is considered as the most important factor affecting DR scheduling. In addition, the first-stage DR is dispatched more frequently when transmission constraints congestion occurs.

Integrating wind power into power systems contributes to existing variability in system operations. Current methods to mitigate this variability and uncertainty focus on using conventional generator ramping capability. There is also the option of using wind power itself to mitigate the variability and uncertainty that it introduces into the system. This paper introduces the concept of a flexible dispatch margin as a means for wind to participate in mitigating net variability and net uncertainty. In providing a flexible dispatch margin, wind generators under-schedule in the hour-ahead energy market in order to have additional expected flexibility available for the real-time market. The implementation of the flexible dispatch margin is analyzed in a two-stage optimization model with recourse to the flexible dispatch margin, flexible demand and generator ramping. This modeling framework combines Monte Carlo simulations with AC OPF analysis, using the IEEE 39-bus test system. Results show that use of the flexible dispatch margin decreases the reliance on peaking generators to mitigate net variability and uncertainty, and also decreases the frequency of price spike events, particularly as wind penetration increases from 10% to 30%. The analysis emphasizes the importance of increasing flexible resource capability as power system variability and uncertainty increase.

Introducing wind generation into an electricity market can incur an extra cost resulting from the volatile nature of wind. To reduce this cost, an alternative stochastic market clearing mechanism is proposed in the literature (Wong and Fuller in IEEE Trans Power Syst 22(2):631–638, 2007; Pritchard et al. in Oper Res 2010; Bouffard et al. in IEEE Trans Power Syst 20(4):1818–1826, 2005). However, implementing a stochastic market clearing can also impose some extra cost on the market. Therefore, it is essential to estimate the efficiency gain resulting from implementing a stochastic market clearing mechanism. We describe the result of an empirical study to quantify value of a stochastic clearing mechanism for the New Zealand electricity market. We extend our analysis for possible larger wind integration in the future.

This paper presents the influence of different regulation strategies on wind energy integration into the existing energy system of Jiangsu. The ability of wind integration is defined in terms of the ability to avoid excess electricity production, to conserve primary energy consumption and to reduce CO2 emissions in the system. Firstly, a reference model of Jiangsu’s energy system is built using the energy system analysis tool EnergyPLAN based on the year 2009. The model results are then compared to actual values from 2009 to validate their accuracy. Based on the reference model, different regulations of Jiangsu’s energy system are compared and analyzed in the range of a wind input from 0% to 42% of the total electricity demand. It is concluded that operating power plants in a flexible way facilitates the promotion of more intermittent wind integration.

This presentation was part of theSP5 & SP6 WEBINAR on Grid solutions to realize 450 GW of offshore wind capacity by 2050.

The authors employed a novel optimization framework coupled with an econometric model of wind to study market performance. One conclusion: in circumstances with high uncertainty in the market – as with high penetration of renewables – relying more on a real-time market, similar to the National Electricity Market in Australia, may be a better way to deal with this uncertainty because it uses updated and more accurate information about the wind variability.

In this paper, a frequency control strategy that overcomes some of the problems associated with the integration of large wind farms into the Mexican Interconnected System (MIS) is presented. In recent years, several wind farms have been installed in the MIS, especially in the southeastern network of the system. Installed wind energy capacity is around 2.2 GW, representing about 3.5 % of the total installed electric power in the grid. Increase of this kind of renewable generation is expected to have a strong effect on the dynamic performance at the MIS, especially when the penetration level of wind farms will be an important contribution of total generation. Transient stability studies conducted on a 3500-bus system of the Mexican grid shows that the developed procedures can greatly improve system frequency performance of the entire Mexican interconnected system.

The integration of offshore wind energy into the existing power system is continuously growing. With the increasing distance of the offshore wind farms (OWF) to the onshore AC transmission systems, HVDC systems are emerging as a preferable solution for the connection of OWF due to their techno-economic advantages in comparison to AC subsea connections. Integrating HVDC systems into the existing AC systems poses various planning and technological challenges. To be able to overcome these challenges a variety of studies has to be conducted, e.g. the HVDC system behaviour under faults. Simulations using electromagnetic transient (EMT) tools represent a generally accepted method to conduct the relevant studies. To increase the trust in the developed concepts subsequent hardware demonstrations would be preferable. However, performing these investigations with full-scale components is often not an option due to unavailability and high costs. As an alternative way, Power-Hardware-in-the-Loop (PHiL) approaches are considered. In this context, a new and worldwide unique laboratory demonstrator - the MMC Test Bench - is set up at RWTH Aachen University as part of the Horizon2020 project PROMOTioN. Here, laboratory-scaled Modular Multilevel Converters (MMCs) are used, which are connected on the DC side by cascaded Pi-line segments. The adjacent AC grids (i.e. offshore wind farms, AC transmission networks) are represented by real-time simulators (RTS) and connected to the MMCs via high bandwidth linear power amplifiers (PA). In this work, the MMC Test Bench is initially described. Afterwards, the PHiL set-up to demonstrate the implemented controls for an OWF connected to shore via an HVDC link is explained. To allow the joint operation of the hardware set-up and the RTS in a stable manner, adequate PHIL interfaces algorithms have to be designed and the scaling between the RTS, the power amplifiers and the hardware is explained. The connection of the OWF represents a special challenge for PHiL demonstrations as the OWF represents a weak AC system with the MMC in grid forming mode. In a next step, the results of the successful demonstration of the interconnection of the OWF via an HVDC link with the MMC Test Bench are presented. The system behaviour in stationary and transient operation is analysed based on the wind farm start-up sequence as well as different cases of wind infeed fluctuations. The results are compared to a simulated full-scale model and deviations are discussed.

Floating offshore wind energy is one of the solutions that can foster the ongoing climate transition in Europe. The ARCWIND project aims to contribute to this topic by considering multiple research activities designed to contribute to the development of multiple floating technologies, identifying high-potential deployment areas while considering their economic viability and the impact that these would have in existing power systems. Regarding the latter activity, a two-step methodology was implemented to first calculate the nodal capacity that existing electricity networks have to absorb energy from these potential new wind farms and secondly to assess the impact at the point of connection. This assessment is performed by identifying grid reinforcement needs, verifying the impact on short circuit current levels and measuring the impact on the existing energy mix at countrywide level. This article includes the description of this methodology as well as its application to six different use cases covering five European countries: Portugal, Spain, France, the United Kingdom, and Ireland. Results obtained seem to indicate that, in most cases, the current power systems have enough capacity for the possible connection of new floating offshore wind farms without major reinforcement needs and that these wind farms can have a major contribution to the countries’ energy mix and to the achievement of established climate targets.

High levels of energy from variable generation sources such as wind and solar photovoltaics (PV) can result in significant curtailment, in which the wind and PV energy cannot be used to serve demand. Adding transmission and energy storage can assist in reducing renewable curtailment, but the relative merits of each enabling technology individually or combined is not well understood. Thus, we compare the role of transmission and storage in reducing curtailment, as well as reducing generation costs from conventional sources. Using a high-fidelity model of the electric power grid, we examine a scenario in which the western portion of the U.S. and Canada reaches 37% energy from wind and 12% energy from solar PV. In the case studied, we find that transmission is generally more effective than energy storage in reducing curtailment, due to the curtailment patterns of wind. However, the interaction between transmission and energy storage shows that the two technologies act symbiotically, meaning that their combined energy value is greater than that of each individually. This analysis demonstrates that fully realizing the benefits of wind resources located far from demand centers will require an effective method to deliver wind power at the right times to the right locations.