Your wastewater will produce green energy at WLSSD

You’re going to help us heat our plant and generate electricity in the very near future. (And you’ll save some money to boot.)

Surprised? Don’t be. This is no “pipe dream”. This is an exciting reality. We’ll be using proven technology, and resources that we already produce!

WLSSD has already started a major project to work toward energy self-sufficiency. This green project uses “biogas” – a methane-rich gas already produced by our wastewater treatment process. That biogas can be used in boilers to heat our plant and in generators to produce electricity.

The gas is produced when we treat and break down wastewater solids that remain after wastewater treatment. We currently use some of the gas to heat buildings, but can’t use it all—the remaining gas is flared off and wasted. With the help of state funding, we plan to heat our plant and produce at least 35 percent of the electricity we need with the gas we are already producing.

Residents and businesses will benefit along with the environment. We serve 17 communities – that’s 140,000 people in three counties – and four large industries. Because electricity is a major part of our expenses and electrical costs are rising, this project will help us control our costs. That’ll help your pocketbook and keep our businesses competitive.

How does it work? Well, bacteria do the work, actually. Wastewater treatment plants, including ours, use helpful bacteria (we call ‘em “bugs”) to break down the nutrient-rich wastes you send us. At our plant, we have two biological stages that bring us to the point where we can generate biogas.

The first stage uses bacteria (“bugs’) to break down and remove solids from wastewater, and uses oxygen to fuel those productive bugs. That’s how we get nutrient-rich materials out of the water and into a second stage to create fertilizer and biogas.

The second stage happens in an oxygen-free environment, where the “bugs” that thrive without oxygen (think swamp bugs) complete the breakdown of pollutants. These bacteria produce the biogas we’ll capture to produce electricity.

We’re asking the legislature for $8.15 million in funding – about a third of the cost – to install two 825 kW generators and equipment to generate electricity with biogas. This simple step will allow us to make about 35 percent of the electricity we use, and also will generate heat we can use in building and for our wastewater treatment processes.

WLSSD spends about $3 million a year on electricity, about one-third of our treatment plant operating costs. We’ve reduced our electricity usage by 18 percent over the last three years, but rising electrical rates have wiped out nearly all those savings.

This project will help us stabilize our costs. That’ll save you some money. And because we also treat wastewater from major industries, it’ll help them compete in a globally competitive economy.

In the future, we have plans to add more wastes, like food scraps or fats, oils and grease, to the digesters so we can produce even more biogas. With additional wastes, we potentially can produce all the electricity we need.

Here’s a short video if you want to watch it: Harnessing Energy from Wastewater

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