The Water/Energy Nexus:
The Benefits of Using Integrated Approaches to
Address Water and Energy Supply and Demand
by: Betsy Marcotte
As concerns over
the adequacy of both energy and water supplies increase, more attention
is being focused on the nexus of water and energy supply and demand.
The nexus represents a series of conditions that result from the interdependence
of water and energy resources, and the role that each plays in the generation
and use of the other.
In regions of the
world where there are well-documented shortages of energy and water,
there are significant opportunities for achieving savings in both resources
through combined approaches that address the demand and supply of both
water and energy.
This presentation
will highlight those regions where the water/energy nexus is particularly
relevant and describe in more detail the nature of the relationship
between water and energy supply and demand in these regions. Generally,
these are areas where water resources are in increasingly short supply
and more and more energy is required to transport water longer distances
or pump it from deeper aquifers. The amount of energy required to deliver
these water resources is further increased through the use of old, inadequate
infrastructure and inefficient water and energy management practices.
In addition, the policy framework governing these transactions is inadequate
to provide the right incentives to promote more efficient water and
energy use. Significant benefits can be derived through integrated approaches
that modify the policy framework and promote better management techniques
for both resources.
Municipal Water Efficiency:
Maximizing the Benefits of Water and Energy Resources
by: Kevin James
In their role as
water providers for almost 50 percent of the world's population, municipal
water utilities play a vital role in managing this often-scarce resource.
As global urbanization continues, municipal water utilities have the
complex task o cost effectively providing water to keep cities functioning.
Limited energy resources, sparse freshwater supplies, and mounting environmental
concerns often serve to make water delivery even more challenging.
Most water utilities
in the world neither maximize the benefits of energy and water resources,
nor minimize their negative environmental impacts. By creating and empowering
comprehensive water efficiency management structures, municipal water
utilities can be in a stronger position to cost effectively provide
water services, ensure adequate energy supplies, and protect the environment.
Case Studies based
on work done by the Alliance to Save Energy in Brazil, India and elsewhere
highlight the water and energy efficiency opportunities for municipalities
on both the supply-side (pumping, leak-reduction, O&M, etc.) and
the demand-side (industries, residential, and commercial).
The Energy-Water Nexus in Indian
Agriculture
by: S. Padmanaban
The performance
of the Indian power sector, the sixth largest in the world, is increasingly
dependent on how efficiently irrigation water is pumped, used and paid
for. Water withdrawal is an energy intensive operation performed throughout
the agricultural sector resulting in a third of the power consumption
in the country being used for the roughly 50% of the national irrigation
consumption extracted from groundwater resources. Highly subsidized
power supply policies for agriculture have major implications for the
overall condition of the power sector and associated water resource,
including impairing state financing and overexploitation of water by
farmers. Compounding the problem is a chronic shortage of power and
under investment in the agricultural/rural power distribution grid,
leading to wasteful and inefficient coping behaviors.
Many regions in
India are already witnessing shortages in water supply and severely
lowered groundwater levels, contributing even more to India's growing
carbon emissions, as considerable additional pumping energy is required
to extract ever deeper water supplies. In addition, overwithdrawal coupled
with the lack of effective groundwater management strategies have led
to the widespread use of lower quality groundwater, exposing affected
populations to potentially serious long-term health risks from arsenic,
fluoride, increased salinity, and microbiological contamination.
Addressing the water-energy
nexus in the Indian agricultural sector requires a strategic combination
of several interdependent program components. USAID/India's initial
strategy is to intervene in three areas:
- Central and state
policy dialogue on power and water sector reform—to develop a
energy/water framework.
- Commercial practices
in rural power distribution—to expand the domain of power planning
beyond the customer side of the electrical meter to encompass the
water well, the exploitation and recharge of aquifers and the management
of the watershed as a whole.
- The agricultural/rural
consumer—to engage a neglected, but crucial constituency in partnership
to advance energy and water use efficiency, thereby improving reform
prospects.
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