A framework for joint management of regional water-energy ... - Orbit

Production of biofuels, which is encouraged by European climate
change mitigation policy, requires a considerable amount of water for
irrigation and processing, and competes for land and water resources
with traditional crops.
Some renewable energy sources with high potential in dry areas may
become problematic if their water demands cannot be guaranteed.
In most cases, climate change may exacerbate the problem. According to
MMA (2005), changes in the hydrological system may affect Spanish energy
policy by: a) reducing hydropower generation, b) increasing power demand
from new desalination plants, and c) increasing power consumption for
groundwater pumping and conveyance in order to cover new water deficits.
Furthermore, new release policies aimed at satisfying agricultural demands
(over hydropower) may reduce power generation (MMA, 2005). Climate
change may also affect the Spanish power system by (MMA, 2005): a) reducing
the efficiency of the Rankine cycle (used in thermal generation), b) increasing
the environmental impact of cooling towers, and c) reducing transmission
capacity. No such assessments were found for Portugal, but the situation
is expected to be similar.
3.2 Hydrological system
The IP covers an area of 583 000 km 2 . Its location and topography, combined
with the effects of atmospheric circulation patterns create a precipitation gradient
with high precipitation in the northwest and low precipitation in the
southeast (Lorenzo-Lacruz et al., 2013). This causes strong variations in the
distribution of water resources among the basins: the Miño-Sil, Duero, Tajo
and Ebro (in the northern half of the country) have high annual discharge;
Guadiana and Guadalquivir have modest discharge; and Jucar and Segura, in
the southeast of the Peninsula have low annual discharge.
These differences in the spatial distribution of water resources, and the differences
in the temporal distribution of precipitation have been compensated
by the construction of a large number of dams that allows for the regulation
of 40% of the natural annual flows in Spain alone (Berga-Casafont, 2003).
3.2.1 Rainfall-runoff model
The seven major basins of the Peninsula were divided into three subcatchments
each and a rainfall-runoff model was setup for the 21 resulting
subcatchments. The rainfall-runoff model was implemented in NAM (Nielsen
and Hansen, 1973), a lumped conceptual modeling system with water balance
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