Q. What got you interested in the energy industry?
A. The importance of energy really grabbed my attention during the oil embargo of the 1970s. Imagine turning 16, getting your driver’s license, and immediately dealing with an energy crisis as gasoline is rationed by your license plate number. It really hit home how energy issues could have such a huge global impact. I went to college and studied mechanical engineering with an emphasis on thermodynamics and energy. After graduating, my first job was designing a biogas-fueled cogeneration system at a wastewater treatment plant.
What keeps me in the industry is that I feel we’re making a difference. I believe that one of our greatest global risks is our interdependence on oil. Energy solutions need to be multifaceted, and our work can be part of the solution by turning waste products into renewable energy sources. It’s very satisfying to look at something that others might consider waste and turn it into a resource.
Q. Can you describe how energy resources can be created from wastewater treatment plants?
A. It comes from a process called cogeneration, which is the simultaneous creation of electricity and heat. Solids resulting from the wastewater treatment process can be sent to an anaerobic digester, where organic matter in the wastewater solids is converted into methane by micro-organisms. This process makes methane, the main component of natural gas, as part of a renewable carbon cycle—what nature takes thousands of years to create, we do in a few days. The fuel that is produced is called biogas, and can be fed to a cogeneration system to simultaneously produce electricity and heat in the form of hot water or steam. Biogas can also be treated into biomethane and used as fuel wherever natural gas is used.
Whether biogas is used for biomethane or cogeneration, it reduces the plant’s carbon footprint, provides clean fuel, and improves community relations, since renewable energy is an important social issue right now. It’s not only good for the environment, but eventually starts paying the client back. Projects may have a higher cost up front, but have a return on investment that makes beneficially using biogas economically sound on its own merit. Ultimately, this nexus of water and energy solutions helps the environment and saves energy costs.
Q. What are some of the driving issues affecting these energy solutions?
A. Many times, we look to technology as a trend-setter and driver of new business, but the necessary tools and technology are available right now. New technology is certainly part of the solution, but often times, the client’s decision-making process drives these projects. Clients may be concerned with the required investment in renewable energy solutions. However, even when money is limited, many clients still want to do the right thing and move forward with projects that benefit their operations, their sustainability, and their bottom line.
Q. Where do you see the industry in 5 years?
A. I don’t see any drastic changes in the immediate future, but rather continued progress towards a sustainable energy portfolio. Eventually, more people will see wastewater treatment plants as resource centers for clean water, fertilizer, and energy.
In the past, interest in renewable energy grew when oil prices increased and waned when prices dropped. Now, we’re starting to get sustainable momentum. We’re at a global breaking point where we are committed to implementing energy solutions that are economically viable, environmentally sound, operationally friendly, and socially acceptable. Energy conversion and resource management will be key global issues moving forward.
Dr. David L. Parry, Ph.D., P.E., BCEE, Senior Vice President, has nearly 30 years of experience in every aspect of wastewater treatment, solids processing, and energy management. He is actively involved as project director, technical advisor, or project manager in wastewater treatment plant projects and other industrial facilities in the United States and Canada.
