Understanding the Nexus

The document argues that conventional 'siloed' policy-making is insufficient to address the interconnected pressures of population growth, urbanization, and climate change on water, energy, and food security. It proposes a 'nexus approach' that integrates management across sectors to identify synergies and minimize negative externalities. The paper details the specific interactions between these sectors—such as the high water intensity of biofuels and the energy requirements of water desalination—and provides case studies from Jordan, Ethiopia, India, and Brazil to illustrate both the risks of non-integrated development and the potential for sustainable, pro-poor intensification.

• Global demand for resources is increasing rapidly, with projections that agricultural production must increase by approximately 70% by 2050 and primary energy availability by 50% by 2035 to meet needs.
• Biofuels are significantly more water-intensive than fossil fuels, requiring between 10,000 and 100,000 litres per GJ of energy, most of which is used for growing feedstock.
• The energy intensity of water production varies greatly by source, with desalinated seawater being the most intensive at 2.6–4.36 kWh per m3, compared to 0.37 kWh for surface water.
• Food production is the primary driver of global water consumption, accounting for 80–90% of consumptive blue water use.
• Climate change mitigation strategies can create new resource pressures; for example, sequestering 3 Gt of carbon per year is estimated to require approximately 2,300 km3 of water annually.
• Urbanization concentrates resource demand and waste, with cities currently accounting for approximately 75% of all greenhouse gas emissions.
• A significant opportunity to increase food security without additional resource costs lies in reducing food losses and wastage, which could be reduced by up to 50% by 2025.
• The 'bottom billion' of the world's population faces severe nexus insecurity, with over a billion people lacking access to sanitation or modern energy sources.

APA

Hoff, H. (2011). Understanding the Nexus. Stockholm Environment Institute. https://www.sei.org/mediamanager/documents/Publications/SEI-Paper-Hoff-UnderstandingTheNexus-2011.pdf

Chicago

Hoff, Holger. Understanding the Nexus. Stockholm Environment Institute, 2011. https://www.sei.org/mediamanager/documents/Publications/SEI-Paper-Hoff-UnderstandingTheNexus-2011.pdf.

Wikipedia

{{cite report |last1=Hoff |first1=Holger |title=Understanding the Nexus |publisher=Stockholm Environment Institute |date=2011 |url=https://www.sei.org/mediamanager/documents/Publications/SEI-Paper-Hoff-UnderstandingTheNexus-2011.pdf |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{hoff2011understanding, author = {Hoff, Holger}, title = {{Understanding the Nexus}}, institution = {Stockholm Environment Institute}, year = {2011}, url = {https://www.sei.org/mediamanager/documents/Publications/SEI-Paper-Hoff-UnderstandingTheNexus-2011.pdf}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }