water-electricity nexus in the gcc
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Water & electricity consumptions are closely interdependent. This strong coupling called the “water-
electricity nexus” varies significantly depending on local climate, resources or technological choices. For
Gulf countries, the scarcity of water resources, the high resort to desalination and considerable water
and electricity consumptions make the nexus strongly unbalanced: water supply is critically dependant
on electricity. This implies decision makers to concentrate their efforts on the initiatives that would
improve the energy efficiency of water supply and more particularly on water reuse.
Freshwater consumption for electricity production /
Desalination to face the lack of resources /
Water is required all along the electricity value-chain, from fossil fuels extraction and transformation to
power generation. However one can distinguish three main steps:
1. Power plant construction & decommissioning, negligible in terms of water consumption
2. Power plant operations & maintenance, negligible in GCC countries in terms of water consumption,
since cooling systems mostly rely on seawater (or dry cooling systems in some specific cases). Cooling
system is by far the largest water-intensive step in generation process. However, as seawater
consumption has no impact on the freshwater scarcity in the GCC countries, it can be considered as
marginal.
3. Fuel production (extraction & refining), which is the most water consuming step although it remains
limited (less than 1L/kWh) and varies depending on the considered fuel. Oil-based electricity
production systems are more water intensive than gas-based systems. Thus, countries mainly relying
on gas have lower electric water intensity (Qatar, UAE and Bahrain) than countries with significant
amount of oil in their generation mix (Saudi Arabia, Kuwait and Oman).
WATER-ELECTRICITY NEXUS IN THE GCC HOW CAN MIDDLE EAST DECISION MAKERS REDUCE ENERGY CONSUMPTION
THROUGH A SMARTER MANAGEMENT OF WATER SUPPLY?
INSIGHT
MARCH 2015
Finally, electricity generation in the GCC countries depends to a limited extent on freshwater resources.
Indeed, except Kuwait, which significantly relies on oil to produce electricity no other GCC country
consumes more than 0.5% of its water withdrawals for its electric production. This results in little
incentives for GCC countries to reduce their water consumption.
Electricity consumption for freshwater production /
Desalination to face the lack of resources /
Freshwater is a critical issue in the Arabic Peninsula. The harsh climate and geographical specificities make
freshwater very scarce in the area. All GCC countries withdraw more freshwater than they actually have
as available resources. Today, to cope with the lack of freshwater resources and the high levels of
consumption, GCC countries decided to intensively resort to desalination. Thereby the access to the sea
(Red Sea or the Gulf), indirectly becomes an access to freshwater. The fact that around 50% of worldwide
desalination capacity lies in the region illustrates the high regional dependence on these technologies.
However, desalination is extremely energy-intensive, both in terms of heat and power. Depending on the
technology used, between 3 and 5 kWh are needed to produce 1 m3 of freshwater. Consequently, countries
for which desalination represents a significant share of their supply mix have access to water at higher
energy costs. It results in high differences between countries in terms of energy-intensity of water supply.
Water supply breakdown & average energy intensity for USA, UAE & Australia in 2011
Sources: USGS, 2010-11; FEWA, 2011-12; Australian Bureau of Statistics, 2011-12
Freshwater production in Gulf countries is then much more energy consuming than in most of other
parts of the world. Thus whereas USA and Australia primarily rely on natural and replenishable sources
(surface & ground water), the UAE highly rely on energy consuming desalination to meet their water needs.
In the end, supplying water in the UAE is 3.5 times more energy consuming than in the USA or Australia.
Consequently, the water-electricity nexus in the Gulf countries is strongly unbalanced in the sense that
dependence of electricity generation on water consumption is marginal when compared to dependence
of freshwater production on electricity. Conversely, US or Australian water-electricity consumptions
interdependencies seem rather balanced partially due to the usage of available surface water resources
for plant cooling purposes.
QUANTIFIED WATER- ELECTRICITY NEXUS IN GCC COMPARED TO THE US AND AUSTRALIA - YEAR 2011
Source: computed by the author based on Worldbank data, 2011
As a synthesis, since current and future projects are already water-efficient, energy savings initiatives will
have a limited impact on freshwater consumption in the region. By way of consequence, it is much more
interesting to focus on water savings, since the nexus is imbalanced in that way. Not only will water saving
initiatives directly mitigate high levels of water consumption in the region, but this will indirectly have a
strong impact on electricity consumption. Thus unlike other countries as the USA or Australia, the GCC
countries better ought to focus their sustainability approach on the water side of the nexus, as it will
positively impact both sides.
Improving energy efficiency in freshwater supply /
Several solutions to raise desalination efficiency /
GCC countries will face important population growth in the coming years and the needs in terms of
freshwater should also increase sharply. ADWEA estimates that to meet the UAE 12M inhabitants' water
needs in 2030 (compared to 8.5M today), water consumption level will rise by 30%. That is why it is
particularly important to improve energy-intensity of water supply. This means a more efficient usage of
desalination or a resort to less energy consuming alternatives.
Considering the high amount of energy it represents, the choice of the desalination technology is critical
and should be perfectly aligned with local challenges in order to reduce the final electricity consumption
required to produce water. But contrasting with the rest of the world, desalination within Gulf countries
mainly relies on distillation processes, much more energy intensive. This is due to the high temperature
and salinity levels of the sea (Gulf & Red Sea), as well as the affordable cost of fossil fuel to power these
energy-intensive processes.
However there are several ways to reduce electricity consumption from desalination like coupling with
a power plant or desalination plants combination. In the first case the excess of heat from electricity
generation is used to heat up water to be desalinated. In the second case, preheated water stems from a
thermal plant to feed a membrane-based one. Both aim at reducing the energy bill.
Foster use of reuse /
Water reuse holds a high potential to bridge the water demand gap in Gulf countries. Indeed, regarding
its power intensity, water reuse is 3 to 5 times less energy consuming than desalination. As an illustration,
Abu Dhabi could save 3.5TWh per year if it decided to provide the 30% increase of water supply needed in
2030 (as planned by ADWEA) only through recycled water instead of relying only on desalinated water.
However, as an order of magnitude, the estimated power savings represent the yearly production of one
of the largest UAE power plant. A massive investment in water reuse would thus avoid building one new
power plant by 2030, to supply the growing water needs of the UAE.
Saving water to help mitigating electricity production /
Freshwater demand management should also be taken into consideration when looking at water
conservation policies. In addition to the optimization of freshwater supply (through less energy-intensive
desalination & water reuse), rationalizing the water consumptions remains one of the most direct ways to
save the energy needed to produce it. In this purpose, two options are worth being considered: water-
saving initiatives for agriculture - the main water consumption centre - and a revaluation of water subsidies
to create incentives for the mitigation of water consumption
Policy makers in the Middle East benefit from several levers in order to implement an integrated water
management within their respective countries. All along the water lifecycle, from its production
(through building best-in-class technologies), its consumption (by mitigating the subsidies) and its
recycling (by increasing the amount of water reused), GCC countries have strong opportunities to reduce
the power intensity of their freshwater and support their development in a more sustainable manner.
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