Cleaning water, creating energy

What if a common, familiar organism, considered a nuisance by many, could be used to clean a city's water supply while simultaneously creating the power it takes to do so? That's a question that Dr. Scott James, assistant professor in Baylor's departments of geosciences and mechanical engineering, seeks to answer.

The focus of his research is algae. He says the slippery substance we find along lakes and rivers can be a tool that creates sustainable sources of energy to help alleviate the high costs cities face to produce clean water.

"There's no silver bullet for the energy crisis that we face," James said. "But, perhaps a piece of silver buckshot is in algal-biofuels."

James' research synthesizes two specific characteristics of algae--they naturally clean water and produce biomass. Algae consume the very impurities wastewater treatment plants seek to remove, making them an efficient filtration system. That consumption creates biomass, which can be converted into algal-biofuels, sustainable sources of energy that could provide much-needed alternatives to fossil fuels.

"The nitrates and phosphates that have to be removed from water anyway are food for algae," James said, "so that's why we use algae to remove it. And if you can remove them with algae and produce biomass, we're killing two birds with one stone."

Baylor's algae research is taking place in partnership with the Waco Metropolitan Area Regional Sewage System (WMARRS). The Baylor Wastewater Research Program is located on-site at WMARSS, providing James and his students with a real-world research lab. Wastewater treatment plants use up to 3 percent of all electricity produced in the United States--a staggering amount for such a relatively small segment of industry.

"Wastewater treatment is typically a municipality or city's largest electrical bill," James said. "But the chemical energy that comes into a wastewater treatment plant is typically 10 times the amount needed to run it. So, if instead of just getting rid of those chemicals, we turned them into biomass and in turn used it to power the wastewater treatment plant, we could save money, and potentially have each wastewater treatment plant be a local power plant that could export energy."

The initial goal of his research is to identify the strains of algae that most efficiently filter wastewater and produce biomass. It's a three-step process. First, James tests algae growing in natural water, then synthetic wastewater. The algae species that make it through those first two phases are then tested in actual wastewater.

"We want to select a strain," James said, "that can quickly consume the nitrates and phosphates so that we can clarify the wastewater, and a strain that grows the biomass to have as an energy source."

The algae strains that pass the test in all three phases are then grown onsite at WMARSS for an outdoor pilot project. If the pilot project proves successful, James envisions WMARSS expanding it into a full-scale project using algae as a sustainable source of water filtration and energy production. It also could lead to this Baylor research and Waco’s adoption of it serving as a model for others in the global push to discover sustainable energy solutions.