A cogeneration project at Atlanta’s R.M. Clayton Water Reclamation Plant didn’t work as well as expected — until the operators found a better place to use the electricity.
In 2012, the plant added a 1,600 kW Caterpillar Inc., Electric Power Division, engine-generator to make better use of biogas from the four anaerobic digesters. Previously the methane had been compressed and stored and used to heat the digesters or to fuel the plant’s two incinerators, but sometimes surplus gas had to be flared. Heat captured from the generator was looped back to the digesters.
The project was a significant sustainability improvement, but
