Water crisis on the cusp of clean energy

11/30/20237 min read

The reality of the water crisis is undeniable. The world is currently facing a critical situation and the energy sector must address this pressing issue.

Simultaneously, the global energy system heavily relies on water resources, consuming approximately 54 billion cubic meters (bcm) of freshwater in 2021. This is defined as the volume withdrawn that is not returned to the source (i.e. is evaporated or transported to another location) and is by definition no longer available for any other use.

Water is finite and essential source that plays an indispensable role in various aspects of energy supply, ranging from electricity generation to fossil fuel production and even the cultivation of biofuels. Recognizing the vital relationship between water and energy is crucial in addressing the water crisis and ensuring sustainable energy practices.

An interesting analysis made by the international Energy Agency (IEA),projected two consumption scenarios depicting Water demand in energy sector by the year of 2030. the aim is to put the emphasis on the necessity of an integrated approach of managing water as part of world wide sustainable goals.

The increasing use of renewable energy holds the potential to mitigate the global water crisis and reduce carbon emissions, which could address climate change and conserve water resources

1- Stated Policies Scenario (STEPS)

The scenario takes into account the policies and implementing measures affecting energy markets that had been adopted as of end of September 2022

Within the framework of the Stated Policies Scenario (STEPS), considered as the most conservative scenario, global water consumption by the energy sector is projected to escalate even further. By the year 2030, it is estimated to reach nearly 62 billion cubic meters (bcm). This surge is primarily attributed to the increase in the use of bioenergy. Water consumption accounts for the irrigation of dedicated feedstock and water use for processing.

it's worth noting that the transition from fossil fuels to renewable energy sources like solar photovoltaic (PV) and wind in the power sector does provide some offset to this increase. However, It is clear that under the STEPS hypothesis water demand will continue to surge mainly due to demographic and economic growth which would still depend on fossil energy considered as a major source of carbon emissions.

2- Net Zero Emission by 2050 Scenario (NZE)

The Net Zero Emissions by 2050 Scenario (NZE) is a normative IEA scenario that shows a pathway for the global energy sector to concretize if the world is to achieve net‐zero emissions by 2050.

Under the Net Zero Emissions by 2050 Scenario (NZE), considered as the most ambitious scenario, it is projected that water consumption (which refers to water no longer available for other uses) will increase by approximately 4 billion cubic meters (bcm) from 2021 to 2030. The most significant reductions occur within the fossil energy, with a global consumption declining by approximatively 50%. The decline is primarily attributed to the rapid replacement of coal-fired power generation with solar photovoltaic (PV) and wind energy sources.

On the other hand, this reduction is outweighed by higher water demand associated with bioenergy production mostly due to increasing use of organic waste and forest and wood residues, which have lower carbon footprint.

Does Low carbon footprint mean less water consumption ?

Compared to STEPS scenario, NZE has indeed an impact on reducing projected water consumption. This is mainly because it favors low carbon energy sectors such as Renewables, Hydrogen and Nuclear power as they have less CO2 emissions.

However, the production of energy in renewable-rich but water-stressed regions requires careful assessment. Indeed, the power sector is particularly vulnerable to growing water stress even with the use of clean energy, and increasing water shortages in dry regions are a major source of concern for global security. For instance, Hydropower generation could decline significantly in regions where water flows are likely to decrease, such as Southern Europe, North Africa and the Middle East. Fluctuations in Hydropower output have already exacerbated the global energy crisis. As an indicator, generated hydropower in 2022 was very poor in latin America, Southern Europe and North Africa, added to the strains on gas and electricity markets caused by Russia’s invasion of Ukraine and the related cuts to pipeline gas deliveries.

As for Renewable energy technologies, It's worth noting that compared to traditional thermal power plants, they generally have lower water consumption and lower water withdrawal rates. However, the specific water requirements can still vary depending on the technology, location, and the overall life cycle of the renewable energy system.

  • Solar PV and Wind Power: These technologies have relatively low water consumption during the electricity generation phase. Once installed, solar panels and wind turbines do not require significant amounts of water to produce electricity.

  • Geothermal Power: Geothermal power utilizes the heat from the Earth's core to generate electricity. Water is often used to extract heat from underground reservoirs or in binary cycle power plants, but the water consumption is generally minimal compared to thermal power plants.

  • Biomass and Bioenergy: Bioenergy production, such as burning biomass or biofuels, can involve water-intensive processes. For example, irrigating bioenergy feedstocks or processing biomass into fuel may require significant amounts of water.

Hydrogen production’s environmental impact is more complicated than it appears. As an energy carrier, it can be produced through different methods, each with its own implications for water consumption. One common method is steam methane reforming (SMR) where natural gas reacts with high-temperature steam to produce hydrogen and carbon dioxide. This process is widely adopted as it is cost efficient compared to electrolysis method ($3-$6/kg vs $9/kg). However, it requires a significant amount of water, with consumption ranging from 9 to 12 kilograms per kilogram of hydrogen produced. While the water used in SMR can be recycled, the overall water footprint remains relatively high.

In contrast, electrolysis method offers a more water-efficient alternative. it involves using an electric current to split water into hydrogen and oxygen gases. Although water is required as a feedstock, it is a closed-loop system where the water consumed can be replenished and recycled. The specific water consumption in electrolysis depends on factors like system efficiency and operating conditions, but it generally represents a lower water footprint compared to SMR.

Electrolysis may appear to be the truly “green” solution, but the energy grid it draws power from may be powered by coal or any other fossil source. For example, Most electrolysis in the US is powered by grid electricity, which is primarily generated from fossil fuels. In these situations, it may be more eco-friendly to use steam methane reforming (SMR) to produce hydrogen from natural gas.

Can we reach a balance ?

It is essential to strike a balance between the benefits of low-carbon energy production and the potential challenges posed to water resources, emphasizing the need for sustainable water management strategies in the energy sector. Energy and water stewardship should go hand by hand as water availability is an increasingly important measure for assessing the physical, economic and environmental viability of energy projects. With the net-zero emissions scenario, there is a great chance that we could achieve both lower CO2 emissions and better water preservation.

However, attaining net-zero emissions remains a complex goal requiring a comprehensive approach. In this pursuit, a combination of strategies can be employed to minimize water consumption while simultaneously reducing CO2 emissions. These actions encompass the following :

Nuclear power generation does play a crucial role in mitigating carbon dioxide emissions, saving the atmosphere from more than 470 million tons of such emissions annually. However, it is important to note that thermal power plants often have substantial water requirements for cooling purposes.

This reliance on such large amounts can pose a significant risk to water security, particularly during drought periods. For example, France’s Chooz nuclear power plant was closed for around two months when a severe drought hit in 2020, and several other plants had to reduce output in 2022 due to lack of cooling water.

Globally, 2 billion people (26% of the population) do not have safe drinking water and 3.6 billion (46%) lack access to safely managed sanitation

Credit : United Nations : The Sustainable Development Goals Report 2022 (Goal 6)

⫸Transition to Renewable Energy including a life-cycle approach

  • Accelerate the adoption of renewable energy sources such as Solar, Wind, and Hydropower. This reduces reliance on fossil fuels and minimizes both CO2 emissions and water consumption associated with traditional energy production.

  • Integrate decarbonization and water preservation measures for Renewable technologies life-cycle to ensure the efficiency of both production and operational phases.

Lowering Freshwater footprint of hydrogen and bioenergy production

  • Hydrogen : Implementing desalination plants running on renewable to limit both the depletion of freshwater resources and reduce CO2 emissions.

  • Bioenergy : Choosing feedstocks that have lower water requirements and are well-suited to local climatic conditions such as drought-tolerant varieties or perennial crops with deep root systems that require less irrigation.

  • Thermal : improving the efficiency of the power plant fleet and deploying more advanced cooling systems such as hybrid cooling.

Energy Efficiency Measures

  • Implement energy efficiency programs in buildings, industries, and transportation sectors to reduce overall energy demand. Energy-efficient technologies and practices help conserve water indirectly by reducing the need for energy-intensive water extraction, treatment, and distribution processes.

Sustainable Agriculture Practices

  • Encourage sustainable agricultural techniques that minimize water-intensive practices such as excessive irrigation. Precision irrigation systems, crop rotation, soil conservation, and water-efficient farming methods can help conserve water resources while reducing the carbon footprint of agriculture.

Water Recycling and Reuse

  • Implement water recycling and reuse systems in industrial processes and municipal wastewater treatment. This reduces water demand, conserves resources, and minimizes energy requirements for water treatment.

Policy and Regulation

  • Enact policies and regulations that promote water conservation and incentivize the adoption of low-carbon technologies. This can include water-use efficiency standards and carbon pricing to encourage sustainable practices across sectors.

Research and Innovation

  • Invest in research and development of technologies that enable water-efficient and low-carbon solutions. This includes advancements in desalination, water purification, renewable energy storage, and sustainable agricultural practices.

By implementing these strategies, we can strive towards a sustainable future where water resources are conserved and CO2 emissions are minimized, fostering an environmentally resilient world.