Colorado’s water utilities, seeking environmental street cred and pushed by citizens, are slashing energy use and carbon emissions.
Denver Water, the state’s largest water utility, uses lots, and lots, and lots of energy every year, some 56 million kilowatt hours. That’s roughly the same amount of power that 6,900 homes would use during that same period, according to the U.S. EPA.
Brian Good, the utility’s chief administrative officer, can cite, almost without limit, one energy use statistic after another. That’s because it is his job to take the utility into a new uber sustainable world, one in which it produces as much clean energy as it uses, a quest in the energy world known as “net zero.”
The utility is on track to hit that mark, system-wide, by the end of next year, according to Good.
The heart of the initiative is the utility’s new headquarters on the west side of central Denver. When it is finished it will generate the electricity it needs and will be able to capture rainwater and wastewater on site, treating it so that it can be reused.
Good and others believe the facility will be the most sustainable facility in Colorado. By operating in a way that reduces climate-damaging greenhouse gas emissions, Good said the utility is helping protect the watersheds that are threatened by a warming climate.
“Our water comes from the environment,” Good said, “so we have to demonstrate that we are doing our part to take care of it.”
Large industrial users, such as water utilities and wastewater treatment plants, are among the biggest users of electricity and, as a result, among the biggest emitters of greenhouse gases.
But that may be changing. Utilities from Grand Junction to Englewood, from Colorado Springs to Boulder and Longmont, are investing heavily in climate-friendly technology.
According to a report by the Colorado Energy Office, industrial operations account for one-third of total energy consumption in the United States.
The state is working hard to change that with new laws and emissions goals. By 2050, Colorado plans to have greenhouse gas emissions slashed to the same levels as 2005, according to Michael Turner, director of commercial and industrial energy services for the Governor’s Energy Office.
Water and wastewater utilities are key players in that initiative, according to Turner. He is leading an effort to help major industrial sectors across the state become more sustainable, and he said water and wastewater utilities, as well as large breweries, are poised to make major contributions to the greenhouse gas reduction effort.
“Denver Water has demonstrated that they want to be at the forefront of the conversation,” Turner said. “But a lot of [utilities] have expansive industrial complexes and they have invested in significant reduction goals and projects.”
Net zero is a sort of holy grail in the sustainability world and Denver Water has been chasing it since 2014.
In 18 months, by the end of 2020, the agency will have replaced its 40-year-old, administration building with a new structure that is net zero and whose inner workings include the ability to use carefully constructed interior wetlands to process rainwater from the roof and wastewater generated on-site so that it all can be reused on the campus. The entire seven-building complex will use nearly 60 percent less energy than the old complex, according to Denver Water spokesman Todd Hartman, dropping from 6.25 million kilowatt hours annually to 2.5 million.
“We need to demonstrate the future of sustainable urban water use but also demonstrate that it is not just water. It’s energy as well,” Good said.
Once the complex opens, it will have one of the smallest eco footprints possible with existing technologies, Good said. Several of the buildings will be at least partially buried to help reduce heating and cooling loads. Electricity use will be offset by an extensive solar grid and by the utility’s seven hydroelectric plants. All told, the $204 million project is expected to save about $4 million a year in energy costs.
In some parts of the project, Denver Water has pushed out ahead of technologies and the regulators who oversee them.
One Denver building inspector visited the site several months ago to examine its hyper-sophisticated plumbing system for wastewater reuse, only to leave early because he had never seen the technology being deployed and could not render a decision on whether it had been properly installed, according to Good.
The effort to reuse wastewater has been particularly challenging with state regulations still being written for on-site wastewater reuse systems.
“We thought it would be great to capture the rainwater off our roof before it hits the ground. We also thought it would be great to capture our wastewater and use it to flush our toilets. Neither of these was legal at the time [planning began],” Good said.
Since then the utility secured a water right to capture the rainwater, but regulations governing how wastewater can be treated on-site and reused have yet to be finalized, though Denver Water is working with the Colorado Department of Public Health and Environment to develop them.
“We eventually got a permit to build the [wastewater] system,” Good said. “But we still don’t have a permit to run it.”
Denver Water’s net-zero initiative comes as concerns over climate change and rising greenhouse gas emissions grow.
But it isn’t the only large utility spending big bucks to slash emissions.
South Platte Water Renewal Partners, which processes wastewater for Englewood, Littleton and several small water districts, next month will become the first wastewater utility in the state to capture the biogas emitted from its waste treatment facility, converting it to natural gas, and injecting it into a pipeline for Xcel Energy. The program benefits the environment by reducing the amount of methane, a highly damaging greenhouse gas, released into the atmosphere. It also allows SPWRP to earn a climate credit, which it then sells in a climate exchange marketplace.
Grand Junction was the leader in biogas capture and conversion, using the natural gas to fuel its fleet operations.
The City of Boulder’s utility division too is preparing to capture and convert its biogas, rather than flaring it off, and will likely sell it to Western Disposal, a regional trash hauler, according to Cole Sigmon, the project engineer overseeing the program. Western will use the gas to power 15 of its trucks as part of a fleet conversion from diesel to natural gas.
Longmont is close to finalizing its own biogas recapture facility and Colorado Springs is in the midst of a feasibility study.
In addition, when the new National Western Center is completed in 2025, it will be heated with waste heat captured from the Metropolitan Wastewater Reclamation District’s wastewater collection system.
At SPWRP, much of the work has been driven by the cities, their citizenry, and their joint quest for sustainability, said Dan DeLaughter, data and regulatory program manager.
“Water and wastewater [operations] account for 35 percent of municipal energy bills,” DeLaughter said. “So we are continuously looking for ways to reduce energy use.”
As the solar panels go up at Denver Water’s new complex and the high-tech interior wetlands are built, Good continues to watch the electric meter reports.
Two years ago, he said, even before the complex was complete, the utility almost hit net zero, thanks to the large amounts of power its hydroelectric plants were able to produce that year.
By the end of 2020, Good believes the utility should be able to fully hit the net zero mark.
“It’s going to be close, but we set a stretch goal. If we miss, we’ll keep plugging away. If we hit it, we will set a new goal,” he said.
Jerd Smith is editor of Fresh Water News. She can be reached at 720-398-6474, via email at firstname.lastname@example.org or @jerd_smith.