A review of land use, visibility and public perception of renewable energy in the context of landscape impact

Highlights

• Wind energy ranks 1st, solar 2nd and hydro 3rd on land use and visibility.

• In the negative perception index wind energy scores 60%, solar 22% and hydro 15%.

• Depending on landscape type any technology can potentially be the least impactful.

• Opposition to renewable energy should not be uncritically attributed to NIMBY.

• Hydroelectric dams have untapped potential for high quality architectural design.

Abstract

Landscape impacts associated with aesthetics have been a persistent cause of opposition against renewable energy projects. However, the current uncertainty over the spatial extents and the rationality of reported impacts impedes the development of optimal strategies for their mitigation. In this paper, a typology of landscape impacts is formed for hydroelectric, wind and solar energy through the review of three metrics that have been used extensively for impact-assessment: land use, visibility and public perception. Additionally, a generic landscape-impact ranking is formed, based on data from realized projects, demonstrating that hydroelectric energy has been the least impactful to landscapes per unit energy generation, followed by solar and wind energy, respectively. More importantly, the analysis highlights the strengths and weaknesses of each technology, in a landscape impact context, and demonstrates that, depending on landscape attributes, any technology can potentially be the least impactful. Finally, a holistic approach is proposed for future research and policy for the integration of renewable energy to landscapes, introducing the maximum utilization of the advantages of each technology as an additional strategy in an effort to expand beyond the mitigation of negative impacts.

Introduction

In the hierarchy of scientific research on renewable energy (RE), landscape impact analysis is generally considered to rank low. Drawing an analogy with the physiological needs of humans that are more fundamental to survival than the needs of belonging and self-completion [1], the generation of energy is arguably of greater significance to humanity than the impact of the utilized technologies on the landscape. Accordingly, matters of efficiency, costs and environmental impacts are generally prioritized over landscape impact analysis of RE.

In countries with developed economies however, the impact of RE on landscapes has been intertwining with its expansion, raising complex social and cultural questions and creating unexpectant economic and developmental implications. Landscape impact analysis has a dual nature, quantitative and qualitative, and is thus described both by variables that can be objectively quantified, such as land use, and more subjective qualitative variables, such as public perception. This complexity, renders the management and mitigation of landscape impact a challenging problem, requiring interdisciplinary analysis. In this study, landscape impact of RE is placed thematically on the field of research on the sustainability and expansion of RE, but its analysis is generally recognized to pertain to several disciplines of applied natural and social sciences, which may approach the issue from different scientific perspectives.

The motivation of this study lies in addressing and reversing the problems associated with the integration of RE into landscapes. In brief, the relationship between RE and landscapes can be characterized as lose-lose because, in the absence of targeted impact-mitigation plans, it can become detrimental to both the development of RE and the quality of landscapes. On the one hand, the development of RE has been delayed, due to landscape-impact opposition, and on the other, in cases where the integration of RE into landscapes is not properly addressed, significant and problematic landscape transformations have emerged.

In the short term, opposition against RE developments on landscape impact grounds, has been causing delays and cancellations, impeding the effort to reduce dependency from fossil fuel and causing significant economic implications. The relevant examples are abundant. In the USA, for example, lawsuits with legal arguments related to landscape, visibility and aesthetics have been consistently filed against wind and, to a lesser extent. Solar energy developments¹ [3], [4], [5], [6], [7], [8]. Renewable energy projects constitute a significant percentage of the large number of projects that have been challenged on environmental grounds, with reference to the National Environmental Protection Act, federal Environmental Quality Acts and Environmental Protection Acts [9], [10]. Indicatively, the economic impact of litigations related to energy projects was addressed in 2010 in a study of 351 challenged and delayed projects, by the US Chamber of Commerce. In that study, it was estimated that the US economy was deprived of a $1.1 trillion short-term economic boost and of 1.9 million jobs annually, due to these legal challenges [10]; a significant percentage of which (45%) was related to RE projects, is grounded on legal arguments on visual and landscape impact. Since specific data on the economic impact of landscape-related cancellations were not found, this study is cited here to demonstrate the general scale of the economic repercussions from the cancellation or delay of large-scale energy projects.

Similar problems have also emerged in the European Union[11], [12], [13], [14]. We present the case of Greece as an example [15]. In Greece, in 2017 and 2018, the installed capacity of only a portion of the major wind energy projects that were challenged summed 1237.7 MW (Table 1). In some of these litigations, landscape impact was not mentioned, but it was often evident from the channels of communication of the opposing groups (public statements and webpages) that it was a significant implicit motivation for opposition. In such cases, other sections of environmental impact assessment studies which are more technical and objective than landscape impact, were mainly targeted, as they are expected to increase the odds of winning the cases [16]. Even though such legal challenges are also affected by landscape impacts, various other challenges that explicitly included legal arguments on landscape impact against wind energy developments, have also been handled by the Hellenic Council of state [17], [18], [19], [20], [21], [22]. The repercussions of this type of opposition are demonstrated by the fact that even though the current installed capacity of wind energy in Greece is 2651 MW (for 2017) [23], the national target set for 2020, in accordance to directives from the European Union [24], is 7500 MW [25]. Therefore, the delay or cancellation of more projects prompts the imposition of fines from the European Union. The exact method of calculation of the fines has not been published yet, but in a relevant study for Ireland, which is almost double the percentage of Greece away from the target of RE utilization, the fines were anticipated in the range of €300–600 million [26].

Overall, it is evident that, in the long term, RE projects will indeed be the cause of massive landscape changes. It is the first time in human history that energy generation has so high land-use demands [27], [28], [29], [30] and that the required infrastructure generates such extensive visual impacts [31], [32], [33]. The scale of the landscape and visual impacts generated from RE, is excellently demonstrated in the calculations of zones of theoretical visibility (ZTV) for wind energy, in literature. Results from large-scale ZTV analyses showed that wind turbines were visible from approximately 17% of the land area of Spain² [34], 21% of the Netherlands [35], 46% of Scotland [33] and 96% of the region of North Jutland, in Denmark [31]. Furthermore, the global effort to increase energy generation from RE, will inevitably further perplex the problematic relationship between energy generation and landscapes. In Europe, for example, the share of RΕ in energy consumption, which in 2018 was 18%, is planned to increase to 27%, by 2030 [36]. It thus becomes evident that the RE transition will continue to be one the greatest forces of transformation of European landscapes in the following decades. Moreover, this transformation is expected to be even more perceivable than the transition from 17% to 27% might indicate. This is due to the fact that RE projects will gradually have to be sited closer to more sensitive locations, from a landscape impact perspective, as suitable locations have decreased due to the current RE expansion [15], [37], [38]. In conclusion, it is clear that, without specialized impact management and mitigation strategies, long-term landscape impacts from RE can be particularly extensive and intrusive.

In the last few decades, significant effort has been put into estimating, managing and reducing the landscape impacts of RE projects. However, so far, research has mostly focused on localized analyses of impacts rather than generic cumulative analyses. With global RE capacity reaching more than 1856 GW [39], [40], [41] at the moment, extensive national and regional data for RE have emerged, allowing for fact-based analyses of landscape impacts that were so far impossible. This study focuses in this exact direction, through the review of literature and data on established metrics of landscape impact. Specifically, the following research questions are addressed: What are the typical landscape impacts of major RE technologies and how do they differentiate? What is the generic ranking of major RE technologies, in terms of landscape impact, based on data from realized projects?

Through the investigation of these questions, the distinct characteristics that render each RE technology impactful are identified and quantified. Thus, the problem of landscape impact of RE is more clearly defined, laying the proper scientific foundations for its mitigation. This concerns both the formulation of better informed and fact-based spatial planning policies as well as the demonstration of novel directions for research on managing and minimizing landscape impacts [7], [42]. Even though some level of landscape impact from the development of RE is unavoidable, there is arguably still room for optimization of the spatial and architectural design of RE, especially in cases where cultural or natural heritage is affected and key elements of local economies, such as tourism or real estate, are threatened [43].

An initial observation in the review of data and literature was that the various RE technologies have been disproportionately researched over their landscape impact. In particular, wind turbines are the basic topic in the majority of literature [44], [45], [46], design guidelines [47], [48], [49], [50], [51], institutional publications [52], [53], [54], [55], [56] and news articles [14], [57], [58] on landscape impact, followed by solar panels [5], [59] and lastly hydroelectric dams. This observation was partially unexpected due to the fact that the type of RE with the highest installed capacity globally is hydroelectricity, followed by wind energy and lastly, solar energy, which could suggest that research interest might be analogous. Since that was not the case, a hypothesis was formed, that this disproportionate distribution of scientific interest, might be indicative of the actual magnitude of impacts generated from each technology. In accordance with this logic, wind energy would be expected to generate the largest impact, followed by solar and hydroelectric energy, in order. Even though parts of this conclusion have already been produced in literature [60], [61], [62], [63], it has neither been completely formulated yet nor been investigated through specialized analysis of large-scale datasets and specialized analysis.

In the introductory Section 1, the context of this study, the research questions and the initial observations and hypothesis were presented. In Section 2 we review three metrics that have been consistently used in the analysis of landscape impacts from RE: land use, visibility and public perception. In particular, in 2.1 Selection of metrics and technologies, 2.2 Study screening we describe the arguments for the selection of these specific metrics and the study-screening procedures and subsequently, in 2.3 Land use, 2.4 Visibility, 2.5 Public perception we describe the literature analyzed, the methods used and the results obtained for each of the three metrics, in sequence. Then, in Section 2.6 we present generic estimates for the landscape impacts of major RE technologies based on statistical analysis and on the utilization of scientific analyses whose results were distinguished for their generic applicability. In Section 3 we discuss the results and explore their significance and their correlations with existing literature. Finally, we present the conclusions in Section 4 and propose directions for policy and future research in Section 5.