Mayor's Office

Press Release


Project designed to lower Houston’s electricity and natural gas use, improve efficiency, lower emissions, and improve operations – Plans include converting waste into fuel


January 25, 2010 -- The City of Houston launched the first phase of an innovative approach to reduce the City’s consumption of electricity and natural gas by wastewater treatment, one of the most energy intensive sectors of City operations. Wastewater treatment uses approximately 34% of the electricity purchased by the City of Houston. City Council voted on December 16, 2009 to authorize Siemens Industry, Inc. to perform an Investment Grade Audit on six facilities, the first step towards implementing an energy savings performance contract program.


The first phase of this long-term program addresses six wastewater treatment plants (WWTPs) operated by the City of Houston’s Department of Public Works and Engineering (PWE), as well as the lift stations servicing those plants. The project sets several concrete goals for these facilities: a significant decrease in the amount of energy used, reduction of criteria air pollutants as well as greenhouse gas emissions, development of more sustainable operations, and disaster resilience. This project will also improve life cycle costs of system operations, as well as help PWE avoid future capital expenses for required plant upgrades. Energy savings measures proposed by Siemens in its initial report address both liquid and sludge processing facilities, as well as the possible decommissioning of up to four WWTPs.


Aside from the significant energy and cost savings, this major project will equip PWE with the technologies and knowledge to reduce the amount of sludge produced as a waste product and to reuse that material as a source of renewable energy to make electricity onsite. This project will use anaerobic digestion to significantly reduce the amount of biosolids produced, thus reducing sludge processing and disposal costs.  The two digesters will produce electricity onsite by generation of methane gas that can be combusted to generate electricity.  By turning a waste product into a fuel source, Houston assumes a leading role in reducing costs and increasing efficiency. The waste heat from this process is used to treat the remaining sludge.  Over the next 20 years, these cost savings and reductions will add up to considerable amounts.  In addition, PWE will take a major step toward energy sustainability by reusing waste products in a beneficial way.  This project provides the opportunity to turn wastewater treatment from a cost to the WWTP operating budget to a net positive contribution. The contract is work order based, and it is envisioned that short term energy savings measures will be implemented in as soon as 6 to 12 months, while engineering o long-term improvements will be ongoing.


Performance contracting is authorized by the Texas legislature.  Energy performance contracting (EPC) creates a methodology to utilize the guaranteed energy savings of the project to pay for the capital costs of the project. Additionally, under a Texas EPC, the energy services company, in this case Siemens, provides a contractual energy savings guarantee, that will generate cost savings to the City for the amount of energy reduced. If the energy savings measures do not produce the guaranteed savings, Siemens must reimburse the City for the shortfall. The monetary savings from these energy reductions pay for the project costs over a number of years. The use of an EPC is an innovative way for Houston and its Public Works Department to address critical infrastructure improvements.


“This project is a key part of our goal of making Houston the nation's energy efficiency capital,” said former Houston Mayor Bill White. “This project represents a commitment by City Hall to improve services to residents without increasing fees.”


Siemens Industry, selected through the qualifications based competitive proposal process authorized by Texas statute, is able to draw on an unprecedented range of internal and external resources to deliver the project‘s goals. “Sustainability begins with energy efficiency,” said Mike Kearney, head of Siemens Energy and Environmental Solutions, “and the City’s focus on its wastewater treatment plants will net Houston’s citizens tremendous environmental and cost-controlling benefits. With a team approach that includes our strategic subcontractor Camp Dresser & McKee, Inc., as well as Siemens companies like Siemens Water Technologies and Turblex, Siemens Industry is able to bring the Public Works and Engineering Department a broad range of technologies and expertise that will ensure the project’s success, and ultimately guarantee the terms of our agreement. It’s going to be a winner for everyone involved.”


This project was designed in partnership with the Clinton Climate Initiative, a program of the William J. Clinton Foundation. CCI is the delivery partner of the C40, a group of large cities around the world that are committed to reducing greenhouse gas emissions. Houston is one of five C40 cities in the U.S. that is developing and executing innovative, large-scale projects that will reduce their greenhouse gas emissions.  CCI provided assistance to the City in utilizing the Texas EPC process to create a novel, best-practice wastewater treatment system retrofit that will save Houston money and emissions.


Brian Yeoman, Houston City Director, Clinton Climate Initiative, said, “The City of Houston has one of the largest wastewater utilities in the United States, and should be commended for its vision and foresight in undertaking this immensely challenging and groundbreaking project.  It invested a significant amount of time and effort in understanding global best practices in wastewater management before undertaking this crucial step.  We are proud to have been able to assist the Mayor’s staff and the Department of Public Works and Engineering in developing this project.”


The facilities covered in the first phase are 69th Street, Almeda Sims, Sims North, Sims South, Clinton Park, Homestead, and the lift stations associated with those WWTPs. The six targeted WWTPs are responsible for a significant amount of the electricity and natural gas purchased by the City. Combined, these six facilities treat an average of approximately 100 million gallons of wastewater every day, representing about half of the City’s wastewater treatment volume on a daily basis. The City of Houston has one of the largest wastewater utilities in the United States, with 39 WWTPs, 421 lift stations, and 7,000 miles of sewer lines.


About the Clinton Climate Initiative:
The William J. Clinton Foundation launched the Clinton Climate Initiative (CCI) to create and advance solutions to the core issues driving climate change. Working with governments and businesses around the world to tailor local solutions that are economically and environmentally sustainable, CCI focuses on three strategic program areas: increasing energy efficiency in cities, catalyzing the large-scale supply of clean energy, and working to measure and value the carbon absorbed by forests. In each of these programs, CCI uses a holistic approach to address the major sources of greenhouse gas emissions and the people, policies, and practices that impact them. CCI is the delivery partner of the C40, an association of large cities around the world that have pledged to accelerate their efforts to reduce greenhouse gas emissions. To learn more about the work of the Clinton Climate Initiative and the William J. Clinton Foundation, please visit