The hidden value of large-rotor, tall-tower wind turbines in the United States

Abstract

<jats:p> The significant upscaling of wind turbine size (nameplate capacity, rotor diameter, and tower height) has, to date, been driven primarily by a goal of minimizing the levelized cost of energy. But with wind’s levelized cost of energy now comparable with that of other generating resources, other design considerations besides cost-minimization have grown in importance—particularly as wind’s increasing market penetration begins to impose challenges on the electric grid. We find that taller towers and larger rotors (relative to nameplate capacity) can enhance the value of wind energy to the electricity system and provide other “hidden” benefits. Specifically, in regions where wind penetration has reached around 20%, we find a boost in wholesale market value of US$2–US$3/MWh. This is augmented by transmission, balancing, and financing benefits that sum to roughly US$2/MWh. The aggregate potential value enhancement of US$4–US$5/MWh is comparable with a 10%–15% reduction in levelized costs. </jats:p>

Solar and wind grid system value in the United States: The effect of transmission congestion, generation profiles, and curtailment

“…Although the trend toward lower specific power turbines has been largely driven by the associated reduction of levelized cost (and by production-based tax credits), the profile smoothing can also alleviate value reduction by spreading wind generation into higher-priced hours. 60,61 One consideration related to the prior discussion comparing our empirical results with prior modeling studies of wind and solar integration costs is that some of the modeling studies suggest that there will be an acceleration of value decline as penetration moves past 30%. This acceleration was linked to increased ''overproduction.''…”

“…Modeled profiles of wind and solar output were ''debiased,'' so as to more closely match generation records. This process has been described in prior work 55,60 and essentially ll OPEN ACCESS involves scaling modeled output to simultaneously match monthly generation recorded at each plant and hourly generation recorded across each ISO. Specifically, an iterative process is used: in the first step, modeled plant profiles are scaled to match their monthly totals; and in the second step, each hour's generation is summed across the ISO, and an hourly scaling factor is developed and applied to all plants so that the total generation in each region matches the recorded total.…”

“…Capacity value was calculated as the function of ''capacity credit'' and the cost or price of capacity in each ISO. Details on the capacity valuation can be found in prior work, 60 but an overview is provided here. Capacity credit is the fraction (ranging from 0 to 1) of a power plant's total nameplate capacity that can be relied upon during times of grid-system stress.…”

Development of a wind turbine gearbox virtual load sensor using multibody simulation and artificial neural networks

“…The development in the field of wind energy has been characterized by the installation of new wind turbines with increasing rated power and the repowering of old turbines and wind farms [1][2][3]. As a result, the load situation in the drivetrain components in a wind turbine (WT) is intensifying [3].…”

Power and Wind Shear Implications of Large Wind Turbine Scenarios in the US Central Plains

“…These trends are being driven in part by the desire to harness higher wind speeds aloft (increasing H) and to increase rotor-swept area (via increased D), though the need for turbine installation and operation at lower wind speed sites also contributes to the rapid increase in D [9]. Installing tall turbines with larger rotors also contributes 'hidden benefits' in terms of transmission, balancing and financing [10]. Over much of the USA, expected annual mean wind speeds increase by 0.5-1.0 ms −1 from 80 to 110 m and by up to 1.5 ms −1 to 160 m height [11].…”