Public Sector


City of Austin, texas

Austin City Landscape

The Opportunity

In early 2007, the City of Austin sought out a partner to help address infrastructure improvement needs at key city facilities and sites – without having to tap in to other designated budgets for city programs. Key facility improvements were needed at the biosolid treatment facility, first responder outpost building, and across city administrative buildings and public parks. Due to historic generator failures at the Hornsby Bend Biosolids Management Plant, the city wanted to reinstitute a cogeneration facility and address historical operational and maintenance problems associated with the on-site combined heat and power system. From interconnection issues with the local utility to streamlining new water conservation technology, the city was ready to implement new measures to drive toward long-term sustainability while improving the functionality and safety of city assets.

The Partnership

The OpTerra team started working with the City of Austin to help address their critical goals for the biogas-to-energy component of the Hornsby Bend Plant’s overall improvement and sustain­ability project. Focused on providing comprehensive solutions that would promote long-term impact for occupants at other city locations, OpTerra subsequently designed and installed various improvements at additional city facilities including HVAC equipment renovations and new direct digital controls in the Adminis­tration and Maintenance Buildings, as well as lighting upgrades in the Administration Building. Energy conservation measures at Austin’s Technicenter, which houses the city’s first responders including the Fire Department, Emergency Medical Services (EMS), warehousing for Fire and EMS, Police Department offices, and the Depart­ment of Small and Minority Business Resources significantly improved performance and reliability of these essential city services. Building off of these successes in city-owned structures, OpTerra installed water utility lines and a water irrigation system that allows reclaimed, non-potable water to be used to irrigate 80 acres the Krieg Field Softball complex.

The Impact

Through their comprehensive energy program with OpTerra, the City of Austin now purchases enough green power to meet 100 percent of its electricity use. Under a net metering agreement supported by OpTerra, excess power will be sold to Austin Energy, creating a new revenue stream for the city. Addressing the city’s demands for a comprehensive program, OpTerra helped ensure that all energy improvements were funded without cutting into the city’s budget. As a result of their strides to improve their carbon footprint in a fiscally responsible way, the U.S. Environmental Protection Agency presented the City of Austin with its Green Power Leadership Award in 2012.

The Technical Scope

  • Digester gas single-engine generator with provision for a second unit
  • Cogeneration system improvements
  • New equipment and upgrades to digester gas handling systems – sulfide removal, digester gas blower/ compressor, moisture and siloxane removal
  • Electrical system integration and utility interconnections
  • New chilled water thermal energy storage tank at building for city’s first responders
  • Instrumentation and control system integration
  • HVAC equipment renovations and new direct digital controls