China’s Rising Hydropower Demand Challenges Water Sector? Beijing Forestry University 20 October 2015@ Beijing, China Junguo Liu, Dandan Zhao, Gerbens-Leenes

China’s Rising Hydropower Demand

Challenges Water Sector?

Beijing Forestry University

20 October 2015@ Beijing, China

Junguo Liu, Dandan Zhao,

Gerbens-Leenes P.W., Dabo Guan

G-science Academies Statements 2012

According to the G-science Academies Statement for the G8 Summit

in 2012,“How to meet human’s water and energy demand”is one of

the three largest global challenges

According to the “Global Risks 2014” of the World Economic Forum Report, water crisis

has been identified as one of the top 10 global risks.

Impa

ct o

n W

orld

Eco

nom

y

Global Risks Landscape 2014

Water Crisis

Likelihood

One third world people already lives in a country with moderate to high water stress

By 2030 nearly half the global population could be facing water scarcity

Oki and Kanae, 2006. Science; Vörösmarty et al., 2000. Science; Vörösmarty et al., 2010. Nature

Global Water Scarcity Assessment

China’s Water Scarcity

Liu et al., 2013. Global Environmental Change 23: 633-643

Water scarcity is a great challenge in China

Water-Food-Energy Nexus: what we have done

1. Food-induced water (and land) footprint in China

2. Biofuel-induced water (and land) footprint in China

3. Biofuel-induced water footprint in US

4. Hydropower-induced water footprint in China

5. Coal-induced water footprint in China

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Animal products Alcoholic beverages Vegetables & Fruits Oil crops & Vegetable oils

Sugar & Sweeteners Cereals & Roots

CWRF

(m3

cap-

1 y-

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Per Capita Water Footprint in China

Source: Liu and Savenije, 2008. HESS

Animal Products

Cereals & Roots

Changing food-consumption patterns are the main cause of the worsening water scarcity in China (Liu et al., 2008. Nature)

Food losses from field to folk

WF of Canada Arable area of Mexico

Liu et al., 2013. Environmental Science & Technology

Biofuel

Type

Feedstock Feedstock biofuel

conversion ratio

Crop

yield

Specific

water

demand

Water

footprint of

biofuel

Land

footprint of

biofuel

kg kg-1 (ton/ton) kg ha-1 m3 kg-1 m3 l-1 m2 l-1

Bioethanol Maize 3 5001 0.844 2.01 4.75

Bioethanol Cassava 6 16226 0.555 2.64 2.93

Bioethanol Sugarcane 15 62563 0.124 1.47 1.9

Bioethanol Sugarbeets 14 20196 0.202 2.24 5.49

Bioethanol Sweet potato 10 20968 0.23 1.83 3.78

Biodiesel rapeseeds 3.27 1595 2.02 5.82 18.05

Biodiesel soybeans 5.57 1741 3.203 15.7 28.16

Average water and land footprint of biofuel produced with different feedstock crops

Yang, Zhou and Liu, 2009.Energy Policy

We were the very few scholars that first question the

Sustainability of first-generation biofuel development.

Results

Dominguez-Faus, Folberth, Liu, et al. 2013. Environmental Science & Technology

Water footprint of corn-based biofuel in the USA

Large-scale hydro-engineering projectsChina’s Annual Hydropower Electricity Production

The Medium- and Long-term Plan of Renewable Energy Development proposed an installed

capacity of hydropower of 300 million kW by 2020, more than double the size in 2007. China’s 12th five-year plan (2011–2015) sets a goal for non-fossil fuel energy to account for

15% of total energy consumption by 2020, with more than half from hydropower

Hydropower energy in China has increased from 1.2 billion kWh in 1949 to 721 billion kWh in 2010 (600 times!!)

Since 2007, China’s gross installed hydropower capacity and hydropower energy generation have been ranked the highest in the world


Large-scale hydro-engineering projectsEnvironmental and Ecological Concerns of Dams and Hydropower

Reduce sediment flux and change temporal

pattern of river discharge to downstream and

ultimately the ocean

Affect biodiversity by inundation, flow

manipulation, fragmentation of habitat

Impact emission of GHGs

Affect regional water supply and water use

(water footprint of hydropower)


Yangtze finless porpoise

An increasing concern about water sustainability of hydropower leads to the need of

an in-depth study on energy-water nexus of hydropower As of 2013, few researchers had attempted to quantify the water footprint of

hydropower production When a reservoir provides multiple functions (e.g. hydropower, flood control,

irrigation and navigation), its WF should be allocated among the different purposes Most studies have attributed a hydroelectric reservoir’s water consumption entirely

to power generation, overestimating the hydroelectric WF Aim: we analyzed the reservoir WFs in China by determining the volume of

freshwater that evaporates from reservoirs and the hydroelectric WF of reservoirs

that generate power

Background

Methodology

Reservoir Water Footprint

Reservoir WF at river basin and national levels

Hydroelectric WF

Product WF of hydropower

Fi, j = 10 × Ei, j × Ai, j

Hi,j = Fi,j × ηi,j

ηi,j = ri,j / Ri,j

fi,j = Hi,j / Gi,j

ratio of annual revenue generated from hydroelectric power (r) to total annual revenue (R) generated by hydroelectric reservoirs

Results

The Chinese reservoir WF totaled

27.9×109 m3 (Gm3) in 2010, with

values ranging from 0.7 Gm3 for

Northwest rivers basin to 8.0 Gm3

for the Yangtze River basin The reservoir WF accounted for

22% of the total blue water WF of

China; this proportion ranged from

5% for Northwest rivers basin to

57% for Southeast rivers basin. Neglecting reservoir WF seriously

underestimates the blue water WF875 reservoirs

Liu* et al., 2015. Scientific Reports 5: 11446

Results

When the reservoir WF is not considered, 3 river basins suffered from a moderate to severe annual water scarcity: Haihe (371%), Huaihe (154%),Liaohe (102%).

When reservoir WF is considered, 4 river basins suffered from a moderate to severe annual water scarcity: Haihe (378%), Huaihe (182%), Liaohe (127%), Huanghe (104%).

Water scarcity is significantly underestimated

when the reservoir WF is not considered.


Results

A moderate to severe water scarcity in six river basins for at least two months

per year: Haihe (12 months), Huaihe (10 months), Liaohe (6 months), Yellow

river (6 months), Northwest rivers (4 months),Songhuajiang (2 months) basins

Monthly assessments can reveal critical seasons when measures should be taken to mitigate or adapt to water scarcity


Results • China's hydroelectric WF totaled 6.6 Gm3

yr-1 in 2010. This was about 24% of the

reservoir WF

• Average hydroelectric product water

footprint (PWF) of 3.6 m3 GJ-1

• PWF varied from 0.001 for Hongyi plant

to 4234 m3 GJ-1 for Zhanggang plant

• Hydropower resources are concentrated

in western regions, where PWF is low;

but energy demand is dominant in eastern

regions with a high PWF. 209 hydropower plants Liu* et al., 2015. Scientific Reports 5: 11446

Discussion The PWF of 3.6 m3 GJ-1 is lower than

several reported hydroelectric PWFs Although many reservoirs are used for

multiple purposes, WF was attributed only

to hydropower in almost all studies before Mekonnen and Hoekstra considered only 35

of the world’s 8689 plants, which accounted

for 8% of global electricity generation We are the first to analyze variances based

on a large number of reservoirs (i.e. 875)

and hydropower plants (i.e. 209) and to

demonstrate the spatial distribution of WF

of reservoirs and hydropower


DiscussionThe Chinese national average

hydroelectric PWF of 3.6 m3 GJ-1 (3600

m3/1012 J) is higher than that of most

other technologiesPWF of wind energy and underground

uranium mining is negligibleWater footprint of electricity from solar

energy, coal-fired and nuclear thermal

energy is generally far below 1.0 m3 GJ-1

Hydropower is not an efficient solution to

energy supply from a water consumption

perspective


Large variation of PWF was

mainly determined by reservoir

area per unit of installed

hydroelectric capacity (). A linear relationship between

PWF and Linear relationship was much

stronger for plants with

hydropower as their main

purpose than those with power

as secondary purpose


The procedure of determining allocation

coefficient:

1. Assess the total economic value of all

ecosystem services provided by the reservoir.

2. Calculate ratio of economic value of

hydroelectricity to total economic value of all

ecosystem services. This ratio is allocation

coefficient

Three Gorges Reservoir is a multi-purpose reservoir with main ecosystem services of flood control, hydroelectricity, navigation, water supply, aquaculture, and recreation

Zhao and Liu*, 2015. Physics and Chemistry of the Earth 79-82: 40-46

Before 2009, hydroelectricity was main service provided by the reservoir, with ηh > 0.6.

The next-largest ecosystem service values were from navigation and aquaculture Before 2009, reservoir provided little flood control, but thereafter, flood control service

increased greatly, accounting for nearly half of total benefit

ηh decreased gradually to 0.41 in 2012Zhao and Liu*, 2015. Physics and Chemistry of the Earth 79-82: 40-46

Take-home Messages

We provided a spatially explicit assessment of reservoir and hydropower WFs by using 875

representative reservoirs and 209 hydropower plants in China

For multi-purpose reservoirs, it is more logical to “share the burden of water consumption”

among the different beneficiaries

Hydropower development pose challenges on water sector; hence, WF should be assessed in

any sustainability evaluation for reservoirs

From a water conservation point of view, eastern China should not further expand its

capacity in hydropower

More holistic analysis should be further done for water-energy nexus of hydropower

Thank you for your [email protected]

Documents

China’s Rising Hydropower Demand Challenges Water Sector? Beijing Forestry University 20 October 2015@ Beijing, China Junguo Liu, Dandan Zhao, Gerbens-Leenes