Water and Energy Nexus in Middle East, North Africa, and the United States

Transcription

1 Aida Tabakovic Elisabeta Poci CE 397 Transboundary Water Resources Water and Energy Nexus in Middle East, North Africa, and the United States Introduction Water and energy are tied together closely. Water extraction, treatment, distribution, and disposal processes consume energy while many technical processes of harnessing, extracting, and producing energy utilize water. This symbiotic relationship is often called the water-energy nexus. Water and energy systems were largely treated independently before when water resources in many countries were abundant. Yet, with rapid population growth and the increasing changes in regional climate and the water cycle, there is a growing need for integrating the planning and design of energy and water systems (1). Figure 1 shows the water energy nexus cycle. Source: Water, Energy and Climate Change: A Contribution from the Business Community. World Business Council for Sustainable Development Fuel Extraction and Refining Figure 1: Water Energy Nexus Cycle Figure 2 shows the maximum, minimum, and average water consumption for unit production of fuel. The grand ranges in values are due to the variations of technologies and

2 processes used. Note, oil production and refining are the most relevant processes in the MENA countries. Electricity Generation Figure 2: Water consumption for fossil fuel extraction and processing (1) An extensive amount of water is used to generate electricity. Water is consumed in a thermoelectric generation system wherein steam is used to drive a turbine to generate electricity. Water is also used for cooling purposes to condense the steam at the turbine exhaust. Note the United States uses almost 3% of its freshwater usage for such systems. Figure 3 shows the water consumption for electricity generation (1).

3 Figure 3: Water consumption for electricity generation in the United States (1) Energy Requirements for Water Energy is needed for the abstraction, purification, distribution, utilization, and disposal. The energy consumption can differ greatly for each process due to geographical, physical, and technological factors. Figure 4 shows the energy consumption ranges per unit volume of water for different water usage processes. One can see that desalination and long distance conveyance are one of the most energy intensive processes. Note the MENA countries are exploring both these features more and more to expand their water supplies. From an energy perspective wastewater treatment and reuse can be much more efficient than desalination (1).

4 Figure 4: Energy consumption per unit volume of water for different water related segments (1) Water and Energy in MENA Current Water and Energy Availability The MENA region represents an extreme case globally in terms of energy and water resources. The region has two-thirds (66%) of the world s known crude oil reserves, but only 1.4% of the world s fresh water supplies. Figure 5 shows the estimated annual renewable supply of water available per person in The countries in the Arabian Peninsula have almost non-existent renewable supplies to support their populations. Iran, Iraq, and Turkey are the only countries that are currently not water deficient. Figure 6 shows the urban water use for the MENA countries. One can see that the water deficient countries use a similar amount of water as the countries with sufficient water supplies (1).

5 Figure 5: Annual renewable water availability in MENA countries per capita (1) Figure 6: Annual urban municipal withdrawal per capita (1)

6 Figure 7a shows the installed operational capacity of electric power plants in each MENA country. Most of the countries have sufficient capacity to meet their electricity needs, because consumption is not constant over time and different seasons and times of day require more energy. Current data suggests that in the next five years electric capacity will increase in all the MENA countries by at least 7%. Figure 7b shows that most MENA countries produce more oil than they use except for Morocco, Israel, Jordan, Palestine, and Turkey (1). Figure 7: (a) Electric capacity as of 2010 and estimated consumption in (b) Petroleum production and consumption in 2009 (1)

7 Figure 8 shows each country plotted on a water and electricity supply and use chart. The bubble size represents each country s 2009 per capita gross domestic product (GDP). Countries located to the left of 1.0 on the water supply axis are the countries which are withdrawing more water than the renewable supplies that are available. Most of these countries have high GDP. The high GDP has also allowed these countries to implement large-scale desalination and ground water pumping. Yet, the fact that oil and gas and fossil groundwater resources are finite shows that there is a need for re-analization of past energy and water policies which may not be sustainable long term (1). Figure 8: Relationship of renewable water supply and withdrawal and electricity consumption and generation capacity (1) The energy system in MENA countries is largely disconnected from fresh water supplies. In contrast, the United States has a heavy reliance on fresh water for cooling in electric power plants. The dependence on energy for water access and production in MENA countries is perhaps higher than that in many other regions in the world, which may make the coupling of water and energy systems highly skewed. The Arabian Peninsula, for example, depends heavily on energy use for obtaining water from underground aquifers and the sea. Figure 9 shows the different sources of water in the MENA countries. Groundwater is the most significant source of

8 water and there is also a significant amount of desalination occurring in the countries. Both of these sources of water are very energy intensive. Lifting water out of the ground requires more energy than using gravity-based conveyance from a surface source, these countries are highly likely to be using a significant amount of energy to access this form of water. It is estimated that Libya and Saudi Arabia use 14% and 10% of the total fuel consumption for groundwater pumping (1). Water-Energy Nexus in the U.S. Figure 9: Sources of water withdrawal (1) The U.S. energy consumption comprises 1/5 of the world energy consumption (2)while the population in the U.S. is only 4.5% of the world s population (3). The average annual energy consumption per capita in the U.S. is around 345 MMBTU (Million British Thermal Units) versus 75 MMBTU per capita globally (2). Similarly to the global scale, 85% of the energy consumed in the U.S. comes from fossil fuels (2), which means, water is being used and/or consumed in different processes of extraction, refining, processing and transportation of energy stored in the fossil fuels. The graph below shows the water requirements for different types of energy sources (2).

9 As it can be noticed, besides fossil fuels, the so called clean energy nuclear power, consumes vast amounts of water in contrast to the renewables such as wind and solar which require minimal water. Source: Figure 10: Water Requirements for different types of energy sources According to the Energy Information Administration, as the U.S. population is expected to grow by about 70 million in the next 20 years the demand for water and energy will increase in the same time. This population growth will be more significant in areas which are already experiencing water shortages, as shown in the map (4).

10 Figure 11: Water Shortages and Population Growth This increased stress on water resources will increase the competition for water among different users, including here the energy sector. Currently, the energy sector in the U.S. is the second largest user of water at 39% after agriculture with 40% (5). The increasing demand for energy will increase in the same time the amount of water withdrawal. In addition, the extraction of the fossil fuels has become more difficult involving advanced technologies such as hydraulic fracturing which uses pressurized water to extract more oil and gas, creating this way a problem of water pollution. A very much anticipated carbon tax or implementation of a cap and trade carbon program will have mixed impacts on the water usage by the energy sector. On one hand, the implementation of a carbon policy would encourage the expansion of green energy such as wind and solar, which require minimal amounts of water. It may in addition encourage the construction of new more efficient power plants. More efficient, means more electricity produced for the same amount of power or heat generated, and therefore less water used (6). On the other hand, the carbon policy will encourage the operation and construction of new nuclear power plants, which are considered to produce clean energy. However, electricity production from nuclear power is very water intensive. As for the existing coal power plants, meeting the standards of carbon emissions once the carbon policy comes in power, will mean

11 decreased efficiency by 25 to 30%, which in turn will increase the amount of water being used during the electricity generation process. Regarding the other energy policies which are already in power such as the Energy Policy Act of 2005, and the Energy Independence and Security Act of 2007, they both highlight the development of domestic energy sources, renewables and nuclear power, and unconventional fuel sources (6). As mentioned above, these policies have mixed impacts on water resources. In terms of energy use by water, considering the predictions for the population increase and the effects of climate change with long periods of drought, severe scenarios of balancing the demand with the resources will represent a real challenge. In order to meet this demand, other water supply sources such as desalination will be considered, but they are associated with a high cost. On the other hand, as the Standards for Water Quality and Environment Protection tend to get more stringent, in order to meet those Standards, the water industry will have to implement more advanced treatment technologies. The advanced water treatment technologies together with desalination are very energy intensive, and here again, we end up in the closed loop between energy and water interdependence. Conclusion Rapid population growth and the increasing changes in regional climate and the water cycle demand for the planning and design of energy and water systems. It is clear that addressing energy and water issues and planning for each of these sectors should be done on a holistic basis considering the strong interdependence between them. Energy policies affect water and water policies affect energy. As the population increases, the demand for water and energy will keep increasing as well. Considering the added effects of climate change, supplying these demands will be a real challenge for the future. Meeting these demands, does not necessarily mean finding new resources of water and energy. Increasing the efficiency of power plants and cars, will make possible to capture and make use of that amount of energy that is currently lost. Practices of conservation should be embraced for both water and energy. Water reuse should be considered as an alternative to water lawns and flush toilets instead of using fresh water. Groundwater aquifers recharge with reclaimed water may be used as a practice to augment the water resources. Questions: 1. President Obama has been following a policy which supports the extraction of oil and gas, as part of the Energy National Security. These policies, do however contradict his plans for energy as a candidate in 2008 where he would speak about combating global

12 warming, carbon capture, and embracement of renewable energies (7). How would you judge President Obama s policies considering the pressure of climate change effects and the troubled Middle East? 2. How can we combat/mitigate the effects of climate change in a world where we do not agree to play by the same rules? U.S. has not implemented yet a carbon policy and Canada withdrew from the Kyoto Protocol, in order to allow for the implementation of the Keystone Pipeline (a project which will supply crude oil from Canada to refineries in the U.S.) 3. The U.S. agricultural water consumption has remained steady overall over the last two decades due to the U.S. economic shift from agriculture to industry. Israel has also seen a decrease of per capita use of water in all sectors of the economy accompanied by an increase in GDP. Can these examples be applied to the MENA countries? 4. Desalination is very energy intensive and yet seems to be increasing in popularity in the MENA region. Considering the different economies of these countries, are there other more environmentally and energy friendly ways these countries can mitigate their water shortage issues? References: 1. The water-energy nexus in Middle East and North Africa. Siddiqi, Afreen and Anadon, Laura D. 8, s.l. : Energy Policy, 2011, Vol Webber, Michael E. Introduction. Energy, Technology & Policy [Online] 4. Energy, U.S. Department of. Energy Demands to Water Resources; Report to Congress on the Interdependency of Energy and Water Bloetscher, Frederic. Energy Management; How can we avoid the coming Power Struggle for Water? Opflow. 2011, Vol. 37, Stillwell, A. Energy-Water Nexus in Texas. s.l. : University of Texas at Austin, New York Times. [Online]