Energy supply chain needs water. Water supply chain needs energy. The connection between water and energy could intensify because of climate change and population growth impacting both sectors.
Water for Energy
The world has a water problem: repeated droughts, floods. The energy sector needs to deal with it. In fact, energy depends on water in its production process including raw materials extraction, cooling in nuclear and thermal processes, hydropower, biofuels production, etc.
World Energy Outlook, released in November 2016, shows that the power sector (including fossil fuels, nuclear and renewables) is the primary source of water withdrawals accounting for 350 billion cubic metres (bcm) and in addition, primary energy production represents the largest source of water consumption with 30 bcm [1]. The above shows that the energy sector’s dependance on water resources is significant.
Many of the climate impacts will be felt through water, which has implications for energy security. For instance, recent droughts have consequences on nuclear and hydropower plants (you can read my article on drought impacts on hydropower).
Water is used to cool the nuclear process. Often nuclear power plants are located near a river, but with droughts there is less water. Water withdrawal limitations are required to protect the water resources and the biodiversity.
Can low carbon energy solve the water problem ?
In advance, we can think that renewable energy causes less water consumption than other energy sources. In reality, the water demand can increase or decrease depending on the technology employed. Indeed, renewable energy such as solar photovoltaic (PV) and wind energy require minimal or no water (except for PV cleaning) because they don’t need water to cool during electricity production. Geothermal power or concentrating solar power (CSP), however, do need water for cooling. World Energy Outlook underlines that the deployment of low-carbon technologies such as nuclear and CSP which require water to cool can have more impact on water resources.
Hydropower is another renewable energy which needs water to generate electricity. Water withdrawing is returned to the river or lake but the water consumption depends on the technology employed : reservoir versus run-of-river projects.
So, low carbon energy doesn’t necessarily mean low water, it really depends on the technology employed.
Energy for Water
Water requires energy to be transformed into resources available for human consumption. The energy is employed to pump, transport, treat, and desalinate water. With repeated drought, water stress could increase over next decades. This phenomenon lead to the use of “non-traditional resources such as saltwater” [2].
Desalination, the process of separating saltwater from freshwater, demands substantial energy. For example, the International Energy Agency (IEA) reported that “in 2023, the energy used by desalination services in the Middle East was equivalent to almost half of all energy consumed by the region’s residential sector” [3].
World Energy Outlook shows that “The water sector accounted for 4% of global electricity consumption in 2014” [4]. The extraction of groundwater and surface water are the main electricity consumers followed by the water treatment.
However, the energy use in the water sector is expected to double (and more) from 2040 [5]. To limit this rise energy, efficiency measures could be implemented such as more efficient equipment.
As a result, the interdependence between energy and water requires a comprehensive approach to preserve these essential resources. It is crucial to strike a balance between their utilisation and implement sustainable measures to ensure long-term availability.
Sources
[1] World Energy Outlook 2016 (iea.blob.core.windows.net)
[2] Energy is vital to a well-functioning water sector – Analysis – IEA
[3] Energy is vital to a well-functioning water sector – Analysis – IEA
[4] World Energy Outlook 2016 (iea.blob.core.windows.net)
[5] World Energy Outlook 2016 (iea.blob.core.windows.net)
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