  In recent years, the energy-water nexus literature has recognized that the
electricity and water infrastructure that enable the production, distribution,
and consumption of these two commodities is fundamentally intertwined. Electric
power is used to produce, treat, distribute, and recycle water while water is
used to generate and consume electricity. In the meantime, significant
attention has been given to renewable energy integration within the context of
global climate change. While these two issues may seem unrelated, their
resolution is potentially synergistic in that renewable energy technologies not
only present low CO2 emissions but also low water-intensities. Furthermore,
because water is readily stored, it has the potential to act as a flexible
energy resource on both the supply and the demand-side of the electricity grid.
Despite these synergies, the renewable energy integration and energy-water
nexus literature have yet to methodologically converge to systematically
address potential synergies. This paper advances an enterprise control
methodology as a means of assessing the techno-economic performance of the
energy water nexus. The enterprise control methodology has been developed in
recent years to advance the methodological state of the art of renewable energy
integration studies and used recently to carry out a full-scale study for the
Independent System Operator (ISO) New England system. The methodology
quantifies day-ahead and real-time energy market production costs, dispatched
energy mixes, required operating reserves, levels of curtailment, and grid
imbalances. This energy-water nexus methodological extension now includes
flexible water-energy resources within the grid's energy resource portfolio and
quantifies the amounts of water withdrawn and consumed. The simulation
methodology is demonstrated on a modified version of the RTS-96 (RTS-GMLC) test
case.
