Are There Synergies in Water Consumption and Greenhouse Emissions Reductions in the Green Electricity Transition between Now and 2050?

Carbon
emissions and water consumption are inextricably
linked
through energy systems, yet the water implications of electricity
defossilization remain under-investigated despite their importance
for economic and energy security, particularly in water-scarce regions.
A considered energy transition can foster reduction synergies in greenhouse
gas (GHG) emissions and water consumption. This study quantifies life-cycle
GHG and water intensities of national and subnational electricity
mixes in the United States, China, and the European Union+ for current
operations and systematically projected scenarios through 2050. A
novel global-warming-potential-to-water-consumption ratio was introduced
to elucidate their relationship and identify synergistic trends. Results
show that ongoing electricity defossilization generally lowers both
GHG and water intensities, but the magnitude and timing of benefits
vary across regions: China’s coal-heavy profile sustains higher
burdens, while the US sees most gains accrue by 2030 under its current
trajectory; however, recent US policy shifts have weakened defossilization
incentives, risking elevated regional water stress. Policy, economic,
and technological uncertainties in US electricity mixes were further
captured by a rigorous Monte Carlo simulation, generating plausible
technology-share ranges across regional grids at three-year intervals.
By decomposing the drivers of GHG and water intensities, this work
offers actionable, region-specific insights to inform low-carbon,
water-efficient electricity planning amid global climate and water-security
challenges.