The blue water footprint of electricity from hydropower

Abstract. Hydropower accounts for about 16% of the world's electricity supply. It has been debated whether hydroelectric generation is merely an in-stream water user or whether it also consumes water. In this paper we provide scientific support for the argument that hydroelectric generation is in most cases a significant water consumer. The study assesses the blue water footprint of hydroelectricity – the water evaporated from manmade reservoirs to produce electric energy – for 35 selected sites. The aggregated blue water footprint of the selected hydropower plants is 90 Gm3 yr−1, which is equivalent to 10% of the blue water footprint of global crop production in the year 2000. The total blue water footprint of hydroelectric generation in the world must be considerably larger if one considers the fact that this study covers only 8% of the global installed hydroelectric capacity. Hydroelectric generation is thus a significant water consumer. The average water footprint of the selected hydropower plants is 68 m3 GJ−1. Great differences in water footprint among hydropower plants exist, due to differences in climate in the places where the plants are situated, but more importantly as a result of large differences in the area flooded per unit of installed hydroelectric capacity. We recommend that water footprint assessment is added as a component in evaluations of newly proposed hydropower plants as well as in the evaluation of existing hydroelectric dams, so that the consequences of the water footprint of hydroelectric generation on downstream environmental flows and other water users can be evaluated.

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The water footprint of electricity from hydropower

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-8-8355-2011 ◽

2011 ◽

Vol 8 (5) ◽

pp. 8355-8372 ◽

Cited By ~ 8

Author(s):

M. M. Mekonnen ◽

A. Y. Hoekstra

Keyword(s):

Crop Production ◽

Water Footprint ◽

Environmental Flows ◽

Stream Water ◽

Electric Energy ◽

Blue Water ◽

Water Users ◽

Hydropower Plants ◽

Average Water ◽

Year 2000

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The green, blue and grey water footprint of crops and derived crop products

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-8-763-2011 ◽

2011 ◽

Vol 8 (1) ◽

pp. 763-809 ◽

Cited By ~ 47

Author(s):

M. M. Mekonnen ◽

A. Y. Hoekstra

Keyword(s):

Water Balance ◽

River Basin ◽

Crop Production ◽

Water Footprint ◽

Grid Cell ◽

Blue Water ◽

Total Water ◽

Grey Water ◽

Global Average ◽

Average Water

Abstract. This study quantifies the green, blue and grey water footprint of global crop production in a spatially-explicit way for the period 1996–2005. The assessment is global and improves upon earlier research by taking a high-resolution approach, estimating the water footprint of 126 crops at a 5 by 5 arc min grid. We have used a grid-based dynamic water balance model to calculate crop water use over time, with a time step of one day. The model takes into account the daily soil water balance and climatic conditions for each grid cell. In addition, the water pollution associated with the use of nitrogen fertilizer in crop production is estimated for each grid cell. The crop evapotranspiration of additional 20 minor crops is calculated with the CROPWAT model. In addition, we have calculated the water footprint of more than two hundred derived crop products, including various flours, beverages, fibres and biofuels. We have used the water footprint assessment framework as in the guideline of the water footprint network. Considering the water footprints of primary crops, we see that global average water footprint per ton of crop increases from sugar crops (roughly 200 m3 ton−1), vegetables (300 m3 ton−1), roots and tubers (400 m3 ton−1), fruits (1000 m3 ton−1), cereals} (1600 m3 ton−1), oil crops (2400 m3 ton−1) to pulses (4000 m3 ton−1). The water footprint varies, however, across different crops per crop category and per production region as well. Besides, if one considers the water footprint per kcal, the picture changes as well. When considered per ton of product, commodities with relatively large water footprints are: coffee, tea, cocoa, tobacco, spices, nuts, rubber and fibres. The analysis of water footprints of different biofuels shows that bio-ethanol has a lower water footprint (in m3 GJ−1) than biodiesel, which supports earlier analyses. The crop used matters significantly as well: the global average water footprint of bio-ethanol based on sugar beet amounts to 51 m3 GJ−1, while this is 121 m3 GJ−1 for maize. The global water footprint related to crop production in the period 1996–2005 was 7404 billion cubic meters per year (78% green, 12% blue, 10% grey). A large total water footprint was calculated for wheat (1087 Gm3 yr−1), rice (992 Gm3 yr−1) and maize (770 Gm3 yr−1). Wheat and rice have the largest blue water footprints, together accounting for 45% of the global blue water footprint. At country level, the total water footprint was largest for India (1047 Gm3 yr−1), China (967 Gm3 yr−1) and the USA (826 Gm3 yr−1). A relatively large total blue water footprint as a result of crop production is observed in the Indus River Basin (117 Gm3 yr−1) and the Ganges River Basin (108 Gm3 yr−1). The two basins together account for 25% of the blue water footprint related to global crop production. Globally, rain-fed agriculture has a water footprint of 5173 Gm3 yr−1 (91% green, 9% grey); irrigated agriculture has a water footprint of 2230 Gm3 yr−1 (48% green, 40% blue, 12% grey).

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The green, blue and grey water footprint of crops and derived crop products

Hydrology and Earth System Sciences ◽

10.5194/hess-15-1577-2011 ◽

2011 ◽

Vol 15 (5) ◽

pp. 1577-1600 ◽

Cited By ~ 783

Author(s):

M. M. Mekonnen ◽

A. Y. Hoekstra

Keyword(s):

Water Balance ◽

River Basin ◽

Crop Production ◽

Water Footprint ◽

Grid Cell ◽

Blue Water ◽

Total Water ◽

Grey Water ◽

Global Average ◽

Average Water

Abstract. This study quantifies the green, blue and grey water footprint of global crop production in a spatially-explicit way for the period 1996–2005. The assessment improves upon earlier research by taking a high-resolution approach, estimating the water footprint of 126 crops at a 5 by 5 arc minute grid. We have used a grid-based dynamic water balance model to calculate crop water use over time, with a time step of one day. The model takes into account the daily soil water balance and climatic conditions for each grid cell. In addition, the water pollution associated with the use of nitrogen fertilizer in crop production is estimated for each grid cell. The crop evapotranspiration of additional 20 minor crops is calculated with the CROPWAT model. In addition, we have calculated the water footprint of more than two hundred derived crop products, including various flours, beverages, fibres and biofuels. We have used the water footprint assessment framework as in the guideline of the Water Footprint Network. Considering the water footprints of primary crops, we see that the global average water footprint per ton of crop increases from sugar crops (roughly 200 m3 ton−1), vegetables (300 m3 ton−1), roots and tubers (400 m3 ton−1), fruits (1000 m3 ton−1), cereals (1600 m3 ton−1), oil crops (2400 m3 ton−1) to pulses (4000 m3 ton−1). The water footprint varies, however, across different crops per crop category and per production region as well. Besides, if one considers the water footprint per kcal, the picture changes as well. When considered per ton of product, commodities with relatively large water footprints are: coffee, tea, cocoa, tobacco, spices, nuts, rubber and fibres. The analysis of water footprints of different biofuels shows that bio-ethanol has a lower water footprint (in m3 GJ−1) than biodiesel, which supports earlier analyses. The crop used matters significantly as well: the global average water footprint of bio-ethanol based on sugar beet amounts to 51 m3 GJ−1, while this is 121 m3 GJ−1 for maize. The global water footprint related to crop production in the period 1996–2005 was 7404 billion cubic meters per year (78 % green, 12 % blue, 10 % grey). A large total water footprint was calculated for wheat (1087 Gm3 yr−1), rice (992 Gm3 yr−1) and maize (770 Gm3 yr−1). Wheat and rice have the largest blue water footprints, together accounting for 45 % of the global blue water footprint. At country level, the total water footprint was largest for India (1047 Gm3 yr−1), China (967 Gm3 yr−1) and the USA (826 Gm3 yr−1). A relatively large total blue water footprint as a result of crop production is observed in the Indus river basin (117 Gm3 yr−1) and the Ganges river basin (108 Gm3 yr−1). The two basins together account for 25 % of the blue water footprint related to global crop production. Globally, rain-fed agriculture has a water footprint of 5173 Gm3 yr−1 (91 % green, 9 % grey); irrigated agriculture has a water footprint of 2230 Gm3 yr−1 (48 % green, 40 % blue, 12 % grey).

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Agro-economic and socio-environmental assessments of food and virtual water trades of Iran

Scientific Reports ◽

10.1038/s41598-021-93928-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Fatemeh Karandish ◽

Hamideh Nouri ◽

Marcela Brugnach

Keyword(s):

Food Security ◽

Water Consumption ◽

Crop Production ◽

Water Footprint ◽

Virtual Water ◽

Environmental Indicators ◽

Blue Water ◽

Water Crisis ◽

Food Trade ◽

Water Limitations

AbstractEnding hunger and ensuring food security are among targets of 2030’s SDGs. While food trade and the embedded (virtual) water (VW) may improve food availability and accessibility for more people all year round, the sustainability and efficiency of food and VW trade needs to be revisited. In this research, we assess the sustainability and efficiency of food and VW trades under two food security scenarios for Iran, a country suffering from an escalating water crisis. These scenarios are (1) Individual Crop Food Security (ICFS), which restricts calorie fulfillment from individual crops and (2) Crop Category Food Security (CCFS), which promotes “eating local” by suggesting food substitution within the crop category. To this end, we simulate the water footprint and VW trades of 27 major crops, within 8 crop categories, in 30 provinces of Iran (2005–2015). We investigate the impacts of these two scenarios on (a) provincial food security (FSp) and exports; (b) sustainable and efficient blue water consumption, and (c) blue VW export. We then test the correlation between agro-economic and socio-environmental indicators and provincial food security. Our results show that most provinces were threatened by unsustainable and inefficient blue water consumption for crop production, particularly in the summertime. This water mismanagement results in 14.41 and 8.45 billion m3 y−1 unsustainable and inefficient blue VW exports under ICFS. “Eating local” improves the FSp value by up to 210% which lessens the unsustainable and inefficient blue VW export from hotspots. As illustrated in the graphical abstract, the FSp value strongly correlates with different agro-economic and socio-environmental indicators, but in different ways. Our findings promote “eating local” besides improving agro-economic and socio-environmental conditions to take transformative steps toward eradicating food insecurity not only in Iran but also in other countries facing water limitations.

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The Water Footprint of Global Food Production

Water ◽

10.3390/w12102696 ◽

2020 ◽

Vol 12 (10) ◽

pp. 2696

Author(s):

Mesfin M. Mekonnen ◽

Winnie Gerbens-Leenes

Keyword(s):

Agricultural Production ◽

Food Production ◽

Crop Production ◽

Water Footprint ◽

Water Productivity ◽

Blue Water ◽

Dietary Shifts ◽

Global Food ◽

Main Consumer ◽

Future Population

Agricultural production is the main consumer of water. Future population growth, income growth, and dietary shifts are expected to increase demand for water. The paper presents a brief review of the water footprint of crop production and the sustainability of the blue water footprint. The estimated global consumptive (green plus blue) water footprint ranges from 5938 to 8508 km3/year. The water footprint is projected to increase by as much as 22% due to climate change and land use change by 2090. Approximately 57% of the global blue water footprint is shown to violate the environmental flow requirements. This calls for action to improve the sustainability of water and protect ecosystems that depend on it. Some of the measures include increasing water productivity, setting benchmarks, setting caps on the water footprint per river basin, shifting the diets to food items with low water requirements, and reducing food waste.

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Assessment of Water Footprint for Koshi River Basin (KRB), Nepal

10.5194/egusphere-egu2020-4395 ◽

2020 ◽

Author(s):

Raj Deva Singh ◽

Kumar Ghimire ◽

Ashish Pandey

Keyword(s):

River Basin ◽

Water Use ◽

Crop Production ◽

Agricultural Land ◽

Water Footprint ◽

Green Water ◽

Blue Water ◽

Total Water ◽

Green And Blue Water ◽

Koshi River Basin

Nepal is an agrarian country and almost one-third of Gross Domestic Product (GDP) is dependent on agricultural sector. Koshi river basin is the largest basin in the country and serves large share on agricultural production. Like another country, Nepalese agriculture holds largest water use in agriculture. In this context, it is necessary to reduce water use pressure. In this study, water footprint of different crop (rice, maize, wheat, millet, sugarcane, potato and barley) have been estimated for the year 2005 -2014 to get the average water footprint of crop production during study period. CROPWAT model, developed by Food and Agriculture Organization (FAO 2010b).For the computation of the green and blue water footprints, estimated values of ET (the output of CROPWAT model) and yield (derived from statistical data) are utilised. Blue and green water footprint are computed for different districts (16 districts within KRB) / for KRB in different years (10 years from 2005 to 2014) and crops (considered 7 local crops). The water footprint of crops production for any district or basin represents the average of WF production of seven crops in the respective district or basin.The study provides a picture of green and blue water use in crop production in the field and reduction in the water footprint of crop production by selecting suitable crops at different places in the field. The Crop, that has lower water footprint, can be intensified at that location and the crops, having higher water footprint, can be discontinued for production or measure for water saving technique needs to be implemented reducing evapotranspiration. The water footprint of agriculture crop production can be reduced by increasing the yield of the crops. Some measures like use of an improved variety of seed, fertilizer, mechanized farming and soil moisture conservation technology may also be used to increase the crop yields.The crop harvested areas include both rainfed as well as irrigated land. Agricultural land occupies 22% of the study area, out of which 94% areas are rainfed whereas remaining 6% areas are under irrigation. The study shows 98% of total water use in crop production is due to green water use (received from rainfall) and remaining 2 % is due to blue water use received from irrigation (surface and ground water as source). Potato has 22% blue water proportion and contributes 85% share to the total blue water use in the basin. Maize and rice together hold 77% share of total water use in crops production. The average annual water footprint of crop production in KRB is 1248 cubic meter/ton having the variation of 9% during the period of 2005-2014. Sunsari, Dhankuta districts have lower water footprint of crop production. The coefficient of variation of water footprint of millet crop production is lower as compared to those of other crops considered for study whereas sugarcane has a higher variation of water footprint for its production.

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A global and high-resolution assessment of the green, blue and grey water footprint of wheat

Hydrology and Earth System Sciences ◽

10.5194/hess-14-1259-2010 ◽

2010 ◽

Vol 14 (7) ◽

pp. 1259-1276 ◽

Cited By ~ 185

Author(s):

M. M. Mekonnen ◽

A. Y. Hoekstra

Keyword(s):

High Resolution ◽

Water Balance ◽

Water Footprint ◽

Grid Cell ◽

Virtual Water ◽

Blue Water ◽

Grey Water ◽

Wheat Production ◽

The Usa ◽

Average Water

Abstract. The aim of this study is to estimate the green, blue and grey water footprint of wheat in a spatially-explicit way, both from a production and consumption perspective. The assessment is global and improves upon earlier research by taking a high-resolution approach, estimating the water footprint of the crop at a 5 by 5 arc minute grid. We have used a grid-based dynamic water balance model to calculate crop water use over time, with a time step of one day. The model takes into account the daily soil water balance and climatic conditions for each grid cell. In addition, the water pollution associated with the use of nitrogen fertilizer in wheat production is estimated for each grid cell. We have used the water footprint and virtual water flow assessment framework as in the guideline of the Water Footprint Network. The global wheat production in the period 1996–2005 required about 108 billion cubic meters of water per year. The major portion of this water (70%) comes from green water, about 19% comes from blue water, and the remaining 11% is grey water. The global average water footprint of wheat per ton of crop was 1830 m3/ton. About 18% of the water footprint related to the production of wheat is meant not for domestic consumption but for export. About 55% of the virtual water export comes from the USA, Canada and Australia alone. For the period 1996–2005, the global average water saving from international trade in wheat products was 65 Gm3/yr. A relatively large total blue water footprint as a result of wheat production is observed in the Ganges and Indus river basins, which are known for their water stress problems. The two basins alone account for about 47% of the blue water footprint related to global wheat production. About 93% of the water footprint of wheat consumption in Japan lies in other countries, particularly the USA, Australia and Canada. In Italy, with an average wheat consumption of 150 kg/yr per person, more than two times the word average, about 44% of the total water footprint related to this wheat consumption lies outside Italy. The major part of this external water footprint of Italy lies in France and the USA.

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Understanding the Spatial-Temporal Changes of Oasis Farmland in the Tarim River Basin from the Perspective of Agricultural Water Footprint

Water ◽

10.3390/w13050696 ◽

2021 ◽

Vol 13 (5) ◽

pp. 696

Author(s):

Aihua Long ◽

Jiawen Yu ◽

Xiaoya Deng ◽

Xinlin He ◽

Haifeng Gao ◽

...

Keyword(s):

River Basin ◽

Crop Production ◽

Water Footprint ◽

Tarim River ◽

Tarim River Basin ◽

Blue Water ◽

Agricultural Water ◽

The Tarim River ◽

Production Water ◽

The Tarim River Basin

The Tarim River Basin in China has predominantly assumed the task of commodity cotton and other high water-intensive crop production in recent years. The spatial matching status of agricultural water and land resources is a prerequisite for local economic development. This paper provides an insight into the spatiotemporal variation trends of agricultural production water footprint and oasis farmland in the Tarim River Basin. The degree of spatial mismatching between oasis farmland and crop production water footprints studied in this paper found how the crop water footprint affected the change in oasis farmland area by sensitivity analysis. Time series data covering the period of 1990–2015 were used for the study. The results showed that the annual variation of crop production water footprint and oasis farmland area have experienced upward trends in Tarim River Basin. The blue water makes the largest contribution to the components of the crop production water footprint in each district (all exceeded 77%). The crop production water footprint and oasis farmland area tend to aggregate towards the eastern region. The level of spatial mismatch between the blue water footprint and farmland area fluctuated during the study period, but it was gradually remedied after 2000, while the spatial mismatch between green water footprint and farmland area gradually worsened. The number of districts with mid and high sensitivity to changes in blue water footprint continuously increased during 1990–2005, which revealed that the change in blue water footprint has an increasing influence on oasis farmland. The results can provide operable recommendations for efficient use of water resources, maintaining oasis suitable farmland scale and agricultural sustainable development in the Tarim River Basin.

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Evaporation from Camargos hydropower plant reservoir: water footprint characterization

RBRH ◽

10.1590/2318-0331.011616021 ◽

2016 ◽

Vol 21 (3) ◽

pp. 570-575 ◽

Cited By ~ 4

Author(s):

Eduardo de Oliveira Bueno ◽

Carlos Rogério de Mello ◽

Geovane Junqueira Alves

Keyword(s):

Water Footprint ◽

Seasonal Pattern ◽

Electric Energy ◽

High Water ◽

Hydropower Plant ◽

Reservoir Water ◽

Hydropower Plants ◽

Minas Gerais State ◽

Meteorological Elements ◽

Installed Capacity

ABSTRACT In recent years, a relevant debate has been raised by a question related to if the hydropower plants indeed represent a non-consumptive use of water resources. In this context, this work was developed at the Camargos Hydropower Plant reservoir, Grande river basin, southern Minas Gerais state, aiming to estimate evaporation rates, which allow the characterization of the Water Footprint in this facility, between the years of 2010 and 2014. Evaporation rates were estimated based on Linacre, Penman and Penman-Monteith methods. Regarding the distribution of evaporation throughout the year, all methods showed the same seasonal pattern, consistent with the meteorological elements behavior that influence this physical process. Although an annual average evaporation considered normal for the studied region (1329 mm) and a small reservoir area (64 km2), this hydropower plant has presented low electric energy production as it is an old facility (more than 50 years) and has low installed capacity. Therefore, Camargos Hydropower Plant has presented, by all methods, a high Water Footprint (130 m3.GJ–1 on average) compared to estimates for other hydropower plants in Brazil and worldwide.

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WATER FOOTPRINT OF CROP PRODUCTION IN TEHRAN PROVINCE

PLANNING MALAYSIA JOURNAL ◽

10.21837/pm.v17i10.634 ◽

2019 ◽

Vol 17 ◽

Author(s):

Somayeh Rezaei Kalvani ◽

Amir Hamzah Sharaai ◽

Latifah Abd Manaf ◽

Amir Hossein Hamidian

Keyword(s):

Water Consumption ◽

Water Scarcity ◽

Crop Production ◽

Agricultural Sector ◽

Water Footprint ◽

Water Productivity ◽

Blue Water ◽

Agricultural Water ◽

Severe Water Stress ◽

Tehran Province

Evaluation of supply chain of water consumption contributes toward reducing water scarcity, as it allows for increased water productivity in the agricultural sector. Water Footprint (WF) is a powerful tool for water management; it accounts for the volume of water consumption at high spatial and temporal resolution. The objective of this research is to investigate the water footprint trend of crop production in Tehran from 2008 to 2015 and to assess blue water scarcity in the agricultural sector. Water consumption of crop production was evaluated based on the WF method. Evapotranspiration was evaluated by applying the CROPWAT model. Blue water scarcity was evaluated using the blue water footprint-to-blue water availability formula. The results demonstrate that pistachio, cotton, walnut, almond, and wheat have a large WF, amounting to 11.111 m3/kg, 4,703 m3/kg, 3,932 m3/kg, 3,217 m3/kg, and 1.817 m3/kg, respectively. Agricultural blue water scarcity amounted to 0.6 (severe water stress class) (2015–2016). Agricultural water consumption in Tehran is unsustainable since it contributes to severe blue water scarcity. Tehran should reduce agricultural water scarcity by reducing the water footprint of the agricultural sector.

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