ArticlePublisher preview available

Impacts from hydropower production on biodiversity in an LCA framework—review and recommendations

The International Journal of Life Cycle Assessment

March 2016
21(3)

DOI:10.1007/s11367-016-1039-3

Authors:

Erik Olav Gracey

BioMar Group

Francesca Verones

Norwegian University of Science and Technology

Purpose Expanding renewable energy production is widely accepted as a promising strategy in climate change mitigation. However, even renewable energy production has some environmental impacts, some of which are not (yet) covered in life cycle impact assessment (LCIA). We aim to identify the most important cause-effect pathways related to hydropower production on biodiversity, as one of the most common renewable energy sources, and to provide recommendations for future characterization factor (CF) development. Methods We start with a comprehensive review of cause-effect chains related to hydropower production for both aquatic and terrestrial biodiversity. Next, we explore contemporary coverage of impacts on biodiversity from hydropower production in LCA. Further, we select cause-effect pathways displaying some degree of consistency with existing LCA frameworks for method development recommendations. For this, we compare and contrast different hydrologic models and discuss how existing LCIA methodologies might be modified or combined to improve the assessment of biodiversity impacts from hydropower production. Results and discussion Hydropower impacts were categorized into three overarching impact pathways: (1) freshwater habitat alteration, (2) water quality degradation, and (3) land use change. Impacts included within these pathways are flow alteration, geomorphological alteration to habitats, changes in water quality, habitat fragmentation, and land use transformation. For the majority of these impacts, no operational methodology exists currently. Furthermore, the seasonal nature of river dynamics requires a level of temporal resolution currently beyond LCIA modeling capabilities. State-of-the-art LCIA methods covering biodiversity impacts exist for land use and impacts from consumptive water use that can potentially be adapted to cases involving hydropower production, while other impact pathways need novel development. Conclusions In the short term, coverage of biodiversity impacts from hydropower could be significantly improved by adding a time step representing seasonal ecological water demands to existing LCIA methods. In the long term, LCIA should focus on ecological response curves based on multiple hydrologic indices to capture the spatiotemporal aspects of river flow, by using models based on the “ecological limits to hydrologic alteration” (ELOHA) approach. This approach is based on hydrologic alteration-ecological response curves, including site-specific environmental impact data. Though data-intensive, ELOHA represents the potential to build a global impact assessment framework covering multiple ecological indicators from local impacts. Further, we recommend LCIA methods based on degree of regulation for geomorphologic alteration and a fragmentation index based on dam density for “freshwater habitat alteration,” which our review identified as significant unquantified threats to aquatic biodiversity.

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WATER USE IN LCA

Impacts from hydropower production on biodiversity in an LCA

framework—review and recommendations

Erik Olav Gracey

&Francesca Verones

Received: 15 May 2015 /Accepted: 13 January 2016 /Published online: 28 January 2016

#Springer-Verlag Berlin Heidelberg 2016

Abstract

Purpose Expanding renewable energy production is widely

accepted as a promising strategy in climate change mitigation.

However, even renewable energy production has some envi-

ronmental impacts, some of which are not (yet) covered in life

cycle impact assessment (LCIA). We aim to identify the most

important cause-effect pathways related to hydropower pro-

duction on biodiversity, as one of the most common renew-

able energy sources, and to provide recommendations for fu-

ture characterization factor (CF) development.

Methods We start with a comprehensive review of cause-

effect chains related to hydropower production for both aquat-

ic and terrestrial biodiversity. Next, we explore contemporary

coverage of impacts on biodiversity from hydropower produc-

tion in LCA. Further, we select cause-effect pathways

displaying some degree of consistency with existing LCA

frameworks for method development recommendations. For

this, we compare and contrast different hydrologic models and

discuss how existing LCIA methodologies might be modified

or combined to improve the assessment of biodiversity im-

pacts from hydropower production.

Results and discussion Hydropower impacts were catego-

rized into three overarching impact pathways: (1) freshwater

habitat alteration, (2) water quality degradation, and (3) land

use change. Impacts included within these pathways are flow

alteration, geomorphological alteration to habitats, changes in

water quality, habitat fragmentation, and land use

transformation. For the majority of these impacts, no opera-

tional methodology exists currently. Furthermore, the seasonal

nature of river dynamics requires a level of temporal resolu-

tion currently beyond LCIA modeling capabilities. State-of-

the-art LCIA methods covering biodiversity impacts exist for

land use and impacts from consumptive water use that can

potentially be adapted to cases involving hydropower produc-

tion, while other impact pathways need novel development.

Conclusions In the short term, coverage of biodiversity

impacts from hydropower could be significantly improved

by adding a time step representing seasonal ecological

water demands to existing LCIA methods. In the long term,

LCIA should focus on ecological response curves based on

multiple hydrologic indices to capture the spatiotemporal

aspects of river flow, by using models based on the

Becological limits to hydrologic alteration^(ELOHA) ap-

proach. This approach is based on hydrologic alteration-

ecological response curves, including site-specific environ-

mental impact data. Though data-intensive, ELOHA repre-

sents the potential to build a global impact assessment

framework covering multiple ecological indicators from

local impacts. Further, we recommend LCIA methods

based on degree of regulation for geomorphologic alter-

ation and a fragmentation index based on dam density for

Bfreshwater habitat alteration,^which our review identified

as significant unquantified threats to aquatic biodiversity.

Keywords Biodiversity .Ecosystem quality .Freshwater

use .Hydropower .Life cycle impact assessment .Review

1 Introduction

In 2011, hydropower contributed 16 % of global installed

capacity of power production (Kumar et al. 2011). There

Responsible editor: Stephan Pfister

*Francesca Verones

francesca.verones@ntnu.no

Industrial Ecology Programme, Department of Energy and Process

Engineering, NTNU, Trondheim 7491, Norway

Int J Life Cycle Assess (2016) 21:412–428

DOI 10.1007/s11367-016-1039-3

Content courtesy of Springer Nature, terms of use apply. Rights reserved.

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A broad range of hydropower systems, classified by project type, system, head or purpose, can be designed to suit particular needs and site-specific conditions. The major hydropower project types are: run-of-river, storage- (reservoir) based, pumped storage and in�stream technologies. There is no worldwide consensus on classification by project size (installed capacity, MW) due to varying development policies in different countries. Classification according to size, while both common and administratively simple, is—to a degree—arbitrary: concepts like ‘small’ or ‘large hydro’ are not technically or scientifically rigorous indicators of impacts, economics or characteristics. Hydropower projects cover a continuum in scale and it may ultimately be more useful to evaluate hydropower projects based on their sustainability or economic performance, thus setting out more realistic indicators. The total worldwide technical potential for hydropower generation is 14,576 TWh/yr (52.47 EJ/yr) with a corresponding installed capacity of 3,721 GW, roughly four times the current installed capacity. Worldwide total installed hydropower capacity in 2009 was 926 GW, producing annual generation of 3,551 TWh/y (12.8 EJ/y), and representing a global average capacity factor of 44%. Of the total technical potential for hydropower, undeveloped capacity ranges from about 47% in Europe and North America to 92% in Africa, which indicates large opportunities for continued hydropower development worldwide, with the largest growth potential in Africa, Asia and Latin America. Additionally, possible renovation, modernization and upgrading of old power stations are often less costly than developing a new power plant, have relatively smaller environment and social impacts, and require less time for implementation. 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