BRINGING ENERGY EFFICIENCY TO THE WATER AND WASTEWATER INDUSTRY: HOW DO WE GET THERE?

Electricity use in 2004 for the water and wastewater industries in the U.S. was approximately 107 billion kWh/yr, or about 3% of retail electricity sales, and is projected to grow to 120 billion kWh/yr by 2010. Currently, energy is consumed in over 161,000 public water systems and over 16,000 publicly owned municipal wastewater treatment works. Energy efficiency improvements and advanced treatment technologies have the potential to slow energy growth while improving water and wastewater processes. The main energy consuming aspects of water systems are distribution pumping, untreated water pumping, and treatment processes, with distribution pumping accounting for the majority of energy use. Though currently relatively small, the share of energy consumption in water treatment processes is growing due to improvements in pumping plant efficiency and requirements for greater levels of water treatment. This paper describes the energy use characteristics of water and wastewater systems and provides a methodology for improving energy management practices.