How a Wastewater Plant Hits Net Zero Energy
A wastewater treatment facility in Gresham, Ore., went beyond net zero energy consumption within 10 years after beginning the journey.
While other cities across the country are working to mitigate the exorbitant amount of energy their wastewater treatment plants consume, the city of Gresham, Ore., has found a way to achieve net zero energy consumption.
Through a 2005 partnership with a private contractor, Gresham's wastewater treatment plant began the process of green energy creation as well as reducing their overall energy consumption. A mere 10 years later, in March 2015, the plant hit net zero for the month, proving they could create as much energy on site as they needed to consume for operations. It was a milestone victory for the city.
Reaching Net Zero Energy Means Reusing Resources
The first to minimizing energy costs was investing in the right tools that would help the plant harness what it already had: methane gas, and plenty of it. In 2005, the city installed its first biogas generator, which would allow the plant to convert methane gas that naturally exudes from wastewater into energy. Five years later, the facility installed solar panels to add to the green energy they were producing.
In 2012, the wastewater plant began accepting restaurant waste, which includes fats, oil and grease, and harnessed the energy by turning the sludge into biogas. This move helped double the facility's production of biogas, and eventually helped push the plant towards its goal of net zero energy.