In a study published online today in Nature Climate Change, Prof Declan Conway and Sabrina Rothausen argue that greater focus on the energy requirements of the water sector will be a crucial part of the policy response to the huge challenges it faces in the coming decades.
Transparency in the water industry's energy use is also likely to be important for it to meet carbon-reduction commitments while responding to other measures of sustainability, such as the need for stricter quality standards and increasing demand.
To date, much attention has been given to the need for sustainable water resource management, but far less to the growing energy use and associated emissions from the water sector, for example through processes involved in water treatment and distribution and domestic heating of water.
"Pressures on water management include stricter water-quality standards, increasing demand for water and the need to adapt to climate change, while reducing emissions of GHGs," said Prof Conway, professor of water resources and climate change.
"The processes of abstraction, transport and treatment of fresh water and wastewater all demand energy. Adapting water management to meet increasing demand, regulatory standards and the effects of climate change will in many cases require greater energy use."
He added: "Energy use in the water sector is growing, yet its importance is under-recognized, and gaps remain in our knowledge. In this study we define the need to integrate energy use further into water resource management and identify opportunities for the water sector to understand and describe more effectively its role in GHG emissions, through regulatory and behavioural responses, to meet future challenges."
Some recent studies have highlighted the importance of GHG emissions from energy use in the water sector. They show that water-related energy use in the US accounts for nearly 5% of total GHG emissions, and the proportion is even higher in the UK, although there it is mostly associated with end uses of water, such as heating. In countries with very high freshwater withdrawals, most of the water is used for irrigation and the energy used in its extraction and transport is often considerable. Estimates for India suggest that emissions from lifting water for irrigation could be as much as 6% of total national emissions.
Climate change represents a huge challenge to the sustainable management of water resources. In recent decades, developments in industrial, agricultural and domestic water use, and in water-quality regulation, have greatly intensified the treatment and transport of water. Moreover, rising demand for food and biofuels, and their international trade, threaten to drive expansion of irrigated cropland and cropping intensity and hence greater use of water for agriculture. These activities generally require high energy consumption and have contributed to increases in energy use in the water sector in many parts of the world.
The 'perfect storm' scenario of sustaining increases in food production given climate change impacts and the need to reduce GHG emissions, together with increasing competition for water, provides a strong rationale for better integration of water and energy use.
There is also a need to achieve better connections between mitigation and adaptation. Consideration of alternative water supply systems, treatment technologies or water allocation may have a tendency to overlook the carbon cost; some measures regarded as sustainable water management, such as desalination, are very energy intensive. This is particularly the case in the absence of regulatory pressure, as is currently the case in most countries.
In Greenhouse-gas emissions from energy use in the water sector, Prof Conway and Ms Rothausen, of the School of International Development, quantify energy use in the water sector and detail the extent of current knowledge on emissions from the water sector and agricultural water use. Their review shows that energy use and GHG emissions in the sector are under-recognized, in part because of differences in the scope of water-sector boundaries, data availability, methodological approaches and whether results are expressed as energy use or GHG emissions.
Ms Rothausen explained: "Although end use often has the highest energy use of all water-sector elements, it has not traditionally been seen as a direct part of the water sector and is often unaccounted for in water management and policy.
"What evidence there is shows that energy use in the water sector is considerable and growing. This growth is likely to continue, sometimes as an unintended policy outcome, with greater pressure to use and maintain quality of water resources. Despite some recent progress, we need to better understand and profile the role of the water sector as a GHG emitter. A co-ordinated view of the water sector will promote more comprehensive assessments of energy use, while standardized methodologies will enable comparisons between assessments of different technologies and processes, and between regions or countries."
Greenhouse-gas emissions from energy use in the water sector is published online on June 26 in Nature Climate Change (DOI: 10.1038/nclimate1147).
Press office | EurekAlert!
Litter is present throughout the world’s oceans: 1,220 species affected
27.03.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung
International network connects experimental research in European waters
21.03.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
27.03.2017 | Earth Sciences
27.03.2017 | Life Sciences
27.03.2017 | Life Sciences