Overplanting in offshore wind power plants in different regulatory regimes

Abstract

The development of offshore wind farms depends on many technical and economic parameters, which requires an integrated planning approach. Some parameters can be controlled by the wind farm developer, and some are determined by the regulatory authorities. Others can be outside control of both. One aspect of optimizing wind farm development is overplanting, which represents the capacity optimization between installed generation capacity and transmission capacity, which allows for a minor share of energy curtailment to increase the overall value of the farm. Quantifying this value also depends on the regulatory framework, which is analyzed here by comparing United Kingdom and Danish conditions. Using a discounted cash flow model, we find that UK conditions are favorable to overplanting from the developer perspective, where the benefit of using the transmission cable more efficiently supports overplanting. In the Danish case, the private‐economic incentive to overplant is minor due to the constraint of linking subsidies to a certain energy output. On the other hand, when the cost of turbines declines relative to transmission system costs, overplanting tends to become more attractive. This is mostly the case when installing wind farms further offshore compared to projects closer to the coast, which has been exerted more and more exerted in the recent years. In a socioeconomic perspective, overplanting is also a viable method to optimize the wind farm technically and economically, if the cost of the additional turbines is less than the value of the additional generation that can be fed into the grid by the transmission line. This article is categorized under: Wind Power > Economics and Policy Wind Power > Systems and Infrastructure

Design and Operation of Energy Systems with Large Amounts of Variable Generation: IEA Wind TCP Task 25 (Final Summary Report)

“…A technically straightforward concept (Figure 33), overplanting's value is mainly determined by the regulatory regime. Offshore WPPs in the United Kingdom show benefits in overplanting (Wolter et al, 2016). The overplanting concept, also referred to as overcapacity, has been applied to WPPs in Portugal since 2007, allowing for the installation of wind capacity of a maximum of 120% of the original grid connection permit.…”

Wind power costs driven by innovation and experience with further reductions on the horizon

“…These may become more prevalent as wind penetrations increase and as wind power plants are increasingly exposed to varying power market prices (e.g., because of the phase‐out of fixed‐price support regimes) (Simpson et al, 2020). Examples of “value‐tailored” design choices include high‐capacity‐factor (i.e., low specific power) wind turbines (Bolinger et al, 2020; Dalla Riva et al, 2017; Hirth & Müller, 2016; Johansson et al, 2017; Wiser, Millstein, et al, 2020), low‐wind speed turbines, overplanting strategies (Wolter et al, 2020), and hybridization (e.g., by incorporating solar photovoltaics or storage) (Dykes, 2020; Gorman et al, 2020). Many of these choices entail higher LCOE (e.g., because larger blades are used) but can result in higher market prices, and hence deliver an improved economic offering of the wind power asset.…”

Export cable rating optimisation by wind power ramp and thermal risk estimation

“…This paper approaches the optimisation of export cable utilisation by means of a novel thermal risk estimation (TRE) algorithm that identify wind power ramp events and estimate its thermal consequences in submarine power cables. The algorithm is tested under hypothetical wind farm over‐planting (WFO) scenarios (where installed capacity is higher than the static cable rating) [3], considering realistic wind power generation profiles and time‐varying ocean bottom temperatures.…”