The rising need for alternative energy sources has led to some creative solutions. One of these solutions is using wastewater as a power source. University Health Network’s (UHN) Toronto Western Hospital and Krembil Discovery Tower are home to a raw wastewater energy transfer (WET) system that reduces the organization’s overall carbon emissions.
The target is to reduce the facility’s emissions by a quarter of 1,000,000 tons over the next three decades.
Wastewater can be converted into a renewable energy source through decomposition. When organic matter decomposes, it releases methane gas. With the organic waste decomposing in wastewater, the resulting methane gas can be used for power.
“Essentially you could think of this sort of like a geo exchange, except instead of just using the ground, we are using a constantly renewing source of thermal energy,” says Edward Rubinstein, director of environmental compliance, energy and sustainability at UHN.
Wastewater still has a lot of contaminants in it, however, that gets filtered out at a certain stage of the process. UHN has had to work with two other entities to make sure the wastewater gets cleaned out so it can be used.
“There is a company we partnered with called Noventa Energy Partners and they have the rights to a technology that can handle the sewage," says Rubinstein. “Sewer water, as you can imagine, can have a lot of stuff in it. You have to be concerned about biofilms. For that, there is a German company called Huber which is a wastewater management company. They have equipment that can extract the wastewater from the sewer and then put it through the shell and tube heat exchanger. However, that heat exchanger is specially designed where they can manage biofilms and things like that.”
The overall project for implementing this WET system has been a success for the Toronto Western Hospital and Krembil Discovery Tower.
According to Rubinstein, there were many benefits from putting the system in place. The main benefits he noted were:
- Significant operational and capital cost savings
- Significant reduction in greenhouse gas emissions
- Added resiliency and redundancy for their heating and cooling systems
Innovative solutions for energy sources such as wastewater being added to the growing list of green energy alternatives increases the options for healthcare facilities to choose from. More and more of these energy sources are being tested in hopes of finding feasible alternatives.
Jeff Wardon, Jr. is the assistant editor for the facilities market.