Proposed western water supply projects are energy- and carbon-intensive, research group says.
Proposed water supply projects are more energy- and carbon-intensive compared to their antecedents, while wind and photovoltaic solar are renewable energy sources that put the least amount of strain on water resources, according to a new report. Released last month by the non-profit environmental law and policy organization Western Resources Advocates, Protecting the West: How Climate and Clean Energy Policies Can Safeguard Water examines the water future vis-à-vis energy for the Interior West U.S.
While the current water-energy tandem is a national issue, it is especially salient in the arid West due in part to geography, decreasing run off from climate change and a Colorado River commonly acknowledged as oversubscribed. Water is withdrawn and consumed by power plants to generate electricity, which is then used to move, purify and heat water. More water use requires more energy use and vice versa.
Many of the reviewed projects incorporate hydroelectric generation to meet part of their energy demand, but the balance should comprise renewable, water-efficient energy sources, said Stacy Tellinghuisen, a water and energy analyst for WRA.
“You could have solar panels on pumping stations, or you could install an equivalent amount of renewable energy elsewhere,” Tellinghuisen said. “It’s a matter of partnering with a regional electric utility.”
Of the eight major supply projects surveyed by the WRA, the Southern Delivery System (Colorado), Yuma Desalting Plant (Arizona) and Carlsbad Desalination Plant (California) are the closest to construction and the most energy-intensive. Energy intensity measures the amount of energy per unit of water, and there is a lot of energy tied up in desalination and the 2,500-foot lift for the SDS.
The WRA recommends that utilities reduce demand before looking for more distant and expensive projects. If the project is deemed necessary, then use renewable energy instead of adding to the atmosphere’s carbon burden.
Tellinghuisen hopes that a new evaluation process for federal projects will put more emphasis on greenhouse gas emissions and supply alternatives.
Environmental impact statements required by the National Environmental Policy Act place too little emphasis on energy demands and generally consider the current costs of electricity without projecting for future constraints, she added.
But that might change with new NEPA assessment principles proposed last December by the White House Council on Environmental Quality. The new guidelines would require planners to consider risks from climate change and non-structural alternatives, such as conservation. The proposal is being evaluated by the National Academy of Sciences, which is expected to rule in November.
Not only would it be a practical change but a philosophical shift too, Tellinghuisen said. “It’s important to make a statement that water utilities are aware of their climate change impacts.”