Saving Energy in Water Reuse Applications

The 900 megawatt Sandy Creek Energy Station in Riesel, Texas deploys some of the most efficient technology for coal-fueled plants utilizing supercritical steam generators and advanced technology solutions that are designed for sustainability through enhanced efficiency, and lower emissions. Moreover, the cooling water is sourced as reclaimed water from a wastewater treatment plant located two miles away in Waco, Texas.

Not only does the community of Waco benefit from providing reclaimed water to the power plant, but advanced valve systems were used to safely and efficiently deliver the reclaimed water to the energy station. The treated effluent flows by gravity to a below ground wet well for storage and pumping where three 16-inch high service pumps deliver the reclaimed water through a 36-inch pipeline to the energy station. Every pump requires a check valve to prevent reverse flow, but instead of the traditional swing check valve, AWWA ball valves were installed.

Ball valves are used for pump discharge applications because they provide significant energy savings. Pumps consume energy to overcome the static head and friction losses. Calculations show that the use of a 16-in. AWWA ball valve in the place of a swing check valve can save $51,700 per valve over the life of the plant. It is clear that valve selection can play an important role in energy savings. Moreover, saving electrical energy also reduces the need for burning fossil fuels and creating greenhouse gases GHGs. On a national average, for every kW-hr of electricity used, about 1.14 pounds of CO2 emissions are generated. So in the example above, the use of a ball valve instead of a swing check valve would result in savings of 368 tons of CO2 emissions per valve over the 40-year life of the system.

Technological advances related to pump control valves provide a significant contribution to energy savings and mitigating climate change. To read how a pump check ball valve works in this application, click here.

Author: Val-Matic