(CN) – A hot shower is the perfect place to consider the impact of climate change on the water-electricity nexus, since you need water and electricity to heat it. Research published in the journal Climate Change on Thursday models the relationship between power and water utilities in the U.S. Midwest, as global climate changes.
“There is no debate that we need stable access to energy and water,” said Dr. Roshanak Nateghi, a professor of Industrial Engineering at Purdue University and an author on the paper. “If we want to accurately capture climate-sensitive demand, we need to look at electricity and water together.”
Many projections show how climate will impact utilities in isolation, rarely considering the combined impacts of water use on power and vice versa. This is particularly important in urban areas where 70% of the population is expected to live by 2050.
“It is crucial that electric utilities have access to accurate and credible models that adequately characterize the climate sensitivity of residential electricity use, as it represents the sector that is most likely to be affected by climate change,” explained researchers from Purdue University in Indiana and the Helmholtz Centre for Environmental Research in Leipzig, Germany, in the study.
Water and power needs overlap both where they are generated—with water used to generate power and power used to treat water for residential use—and at consumption where appliances like dishwashers and water heaters require input from both sources to work.
Since warmer temperatures are likely to lead to higher uses of air conditioners and droughts to higher uses of sprinklers, researches stressed the need, “for water and electric utilities to work together to prepare for climate change and make decisions that are the best for both sectors.”
While this study focused on the Midwest, from Cleveland to Chicago and Minneapolis, Nateghi said her team plans to adapt the model to project increased utility demand across the whole country.
As the Midwest experiences higher temperatures and drought, researchers found a likely spike in summer water demand and a drop in electricity use in the winter.
Researchers caution that utility providers will need to prepare for “the additional challenge of managing fluctuations, especially for electric utilities, which lack the storage capabilities of most water utilities.”
This model anticipates Chicago’s power demand increasing by 12% and water demand increasing 4%. Overall, the model projects electricity consumption in the Midwest going up by 19% and water by 7%.
“Chicago is more urban (as opposed to suburban) with less residential green space (i.e., yards) than the other cities on the list. This likely leads to lower summer water consumption for outdoor landscaping, and thus a somewhat lower increase in median water demand when compared to the other cities,” researchers explain. “Minneapolis is the northern-most city in the analysis, and likely to see less of a severe summer temperature increase then the other cities.”
The model doesn’t calculate overall demand, just percentage of increased demand in response to the 2.7 degrees Fahrenheit of warming scenario projected for 2030, and the increase of 3.6 degrees expected to hit the planet by 2055.
In addition to considering water and power use in conjunction with one another, this model factored in humidity and wind speeds, as well as average maximum air temperature, average dew point temperature and accumulated precipitation.
Humidity levels and wind speed affect experienced temperatures but are also important variables in modeling potential water demand.
Since the study focuses on end-user demand, these projections might sound an alarm to spur energy-efficient cultural changes like retrofitting homes, using energy efficient appliance and, yes, turning off lights when you leave the room.
“The overlooked portion is that the climate sensitivity portion has been really underreported in a lot of reports, and if you don’t anticipate for it and you don’t plan for it, you are going to see supply shortages,” Nateghi cautioned.
The ISI-MIP project and creation of the selected feature model was funded by the German Federal Ministry of Education and Research and a grant from the National Science Foundation.