The Challenge of Balancing Conservation & Efficiency
By Jeff Baldwin
Those interested in water conservation must also promote the development of performance measures that ensure products operate efficiently.
The B-0107-C from T&S Brass and Bronze Works, Inc. was the first prerinse spray valve brought to the market in the 1980s.
For the last few decades, water conservation has been considered merely a response to drought emergencies. More recently, water conservation has become an important component of environmental resource planning. State and local governments have looked to water system managers for direction and funding, but the public and private sectors continue to see significant reductions in available fresh water resources.
Importance of Water Efficiency
In an effort to legislate water conservation into plumbing products, Congress passed the federal Energy Policy Act of 1992. EPAct 1992 attempted to regulate the volume of water that could flow through residential, commercial and industrial equipment in an effort to conserve the valuable resource of fresh water. However, the law neglected to integrate the concept of water performance efficiency–a key factor in water conservation. It became painfully obvious that actual water conservation suffers when performance efficiency is not considered.
As an example, to comply with the 1.6 gallons per flush maximum as mandated by the EPAct 1992, toilet manufacturers introduced low-flow toilets. Most of the early models were quickly associated with performance problems. Consumers were forced to flush multiple times, conserving less water and generating mounting frustration with the lack of performance. Americans consume almost 4.8 billion gallons of water daily by flushing toilets and urinals. Because the industry responded to the market, more recent models have improved designs and performance efficiency.
Conservation and Efficiency
Conservation is an attainable goal for water resources. However, it is counter-productive to limit water flow without improving the technology. We have learned this over the course of the last decade. Instead of merely prescribing a number of gallons per cycle, per flush or per minute for particular products, the plumbing industry and government regulators are developing reliable performance measures to ensure products are operating efficiently.
All organizations interested in water conservation–such as advocacy groups, public utilities, plumbing manufacturers, consumers and regulators–should understand the complementary differences between conservation and efficiency.
Water conservation is typically associated with the regulation of water use. In the Southwest, state and local governments regulate lawn watering and automobile washing to manage how and when water is used. It may be common to hear "conservation" and "efficiency" used interchangeably, but they actually have two different meanings. Water efficiency refers more to improved technologies and practices. For instance, the use of electronic sensor faucets for washing hands is a prime example of water efficiency.
Improving Technology and Changing Behaviors
Improved technology is only half the picture with water efficiency. Changing the behavior of the consumer or the employee is also required in an effort to conserve water–and changing a behavior can often be accomplished without great capital expense. The public utility companies have endeavored to educate consumers on the values of energy conservation for several years, as evidenced by leaflets in our monthly utility bills.
Improving technology and changing behaviors in the commercial environment are important factors in gaining the competitive advantage. Before implementing water efficiency measures, you must consider a few very significant questions:
- Are the measures compliant with public health sanitation requirements, such as USDA, FDA and all state and local health regulations?
- Are the measures compliant with environmental requirements, such as water quality reuse guidelines?
- Are the measures compliant with other health and safety requirements, such as state and local building codes and fire safety codes?
- Are the measures supportive to customer quality expectations, such as product cleanliness?
After you've answered these questions, then you should determine whether your established procedures follow best practices. It is easy to lose control of water use if equipment and behaviors do not follow best practices. One best practice that has proven to save significant dollars is the installation of pre-rinse spray valves as part of the dishwashing area of the kitchen.
Pre-rinse spray valves are used for the rinsing of cooking utensils, pots, pans, soaking dishes and cleaning. They are designed with automatic shut-off valves integral to the unit to supply water only when needed. There are water-efficient pre-rinse spray valves offered that supply from 1.2 gpm to 1.6 gpm at 60 psi. These types of sprayers are designed to meet the rigorous demands of food service operations, where continuous use and periodic abuse is the norm rather than the exception.
Water Efficiency Programs
Concern over water efficiency has grown so fast that several states have established programs for the commercial and industrial sectors. These states have conducted research studies and onsite audits, implemented employee and consumer education efforts and proposed industrial reuse plans. Over the years, the programs in these states have achieved billions of gallons in water savings and proven to cost-effectively extend the lifespanof available water supplies. The programs have been well developed in California, Arizona, Washington, Massachusetts and New York.
As one of the most notable efficiency programs in the nation, the Rinse and Save program in California boasts a proven record of water conservation and efficiency. The program was implemented through the California Urban Water Conservation Council (CUWCC). Before implementing the program, the council conducted a research study to determine the feasibility of proposed conservation and efficiency techniques.
The CUWCC program has been so successful that it has grown to the national level. The Alliance for Water Efficiency (AWE) was created as a joint effort between the Environmental Protection Agency (EPA) and the CUWCC. It will serve as a clearinghouse and advocate for water efficiency research and education, and help to develop national programs for water conservation and efficiency.
The AWE will work through many different organizations to educate the water efficiency community on the application of water efficiency standards. It is hoped that the proactive involvement of water conservation interests will generate more-efficient products. For example, the maximum urinal flush volume may be reduced from 1.0 gallons to 0.5 gallons. The standard for commercial pre-rinse spray valves may also be adjusted accordingly to maximize cleaning times. In order to achieve this success, the water conservation community is expected to significantly increase its role with the national plumbing codes and product standards.
Commercial Pre-Rinse Spray Valves
The creation of the AWE will mean that product standards previously accepted on the state level will be considered on the national level. Pre-rinse spray valves are sure to be on the national product standards list. The CUWCC Pre-Rinse Spray Valve Distribution program has been very successful. In addition to conserving water, the program also has a documented record of reducing the gas and electric energy required to heat the water. Although these sprayers are limited to 1.6 gpm, they must perform sufficiently to meet all health regulations and customer expectations.
A low-flow pre-rinse spray valve is one of the easiest and most cost-efficient energy-saving devices available to the food service operator. Just as the industry responded to the 1.6 gallons per flush regulations on toilets and urinals, it also is responding to current regulations for pre-rinse sprayers to maintain efficiency. Newer spray valves now provide both water savings and performance efficiency.
Pre-rinse spray valves typically include a nozzle, squeeze lever and dish guard bumper. The spray valves usually have a clip to lock the handle in the ON position. The older spray valves typically provide a flow of 4 to 6 gpm. Replacing these typical spray valves with a low-flow unit can yield the results shown in Table 1.
Food Service Technology Center
The Food Service Technology Center (FSTC) is the industry leader in commercial kitchen energy efficiency and appliance performance testing. The FSTC is based in San Ramon, CA, and operated by Fisher-Nickel. The organization has developed more than 30 standard test methods for evaluating commercial kitchen appliance performance.
Figure 1. Pre-Rinse Spray Valves B-0107-C (top) and B-0108 perform a "cleanability test" to the standard ASTM F2324-03 at the lab of T&S Brass and Bronze. Performance and approval are based upon the timed usage constraints and water consumption when applied in warewashing conditions. The test requires that the valves clean at a flow rate of 1.6 gpm within 26 seconds per plate. Valve 0107 produces a fan spray at less than 1.24 gpm; valve 0108 produces a showerhead spray at less than 1.48 gpm.
The FSTC recommends that a prerinse spray valve with a flow rate of 1.6 gallons per minute have an efficiency performance of 26 seconds per plate or less, based on the ASTM F2324-03 test method (see Figure 1). The Federal Energy Management Program (FEMP) also outlines very similar recommendations for commercial pre-rinse spray valves.
One key feature available from the FSTC Web site is a tool that calculates savings based on water flow rates (new vs. old unit), operating hours per day and days per year, water heater fuel type and efficiency, and water temperature. All of these factors have significant impact on water efficiency and performance. Find the Pre-Rinse Spray Valve Calculator at http://www.fishnick.com/tools/watercost.
Spray valves with high-velocity spray patterns have shown better cleaning performance than those that use a flow restrictor to achieve the required flow rates. Pre-rinsespray valves are inexpensive and easily interchangeable with different manufacturers' pre-rinse faucet assemblies. A typical pre-rinse valve lasts about five years unless it is of substandard manufacture, improperly installed or used in a facility with poor water quality.
Because scale buildup reduces their effectiveness and lengthens dishwashing times, pre-rinse spray valves should be cleaned at least once a year. However, for severely clogged valves, it is more cost-effective to replace the valve with a new lowflow model instead of "drilling out" the scale–a practice that lowers spray velocity, increases water use and reduces the overall cleaning performance.
Conclusion
The water conservation challenges of the last decade have taught us much about the differences between conservation and efficiency. Participation by the plumbing industry in the efforts of national organizations such as the Alliance for Water Efficiency will help to move water-conserving technology forward. Only through a combination of improved technology and behavior changes will we be able to achieve water conservation objectives.
Water conservation is not merely an emergency measure, but one that will help to preserve water supplies (both surface and groundwater) and provide cost savings in water treatment. Water efficiency will indeed support the bottom line profitability of any commercial establishment. Companies that have a holistic strategy for water management will have a competitive advantage over companies that choose to wait.