By Scott Petty
The upcoming U.S. Department of Energy (DOE) regulations for pool pumps will change the industry more than any other issue in recent memory. All manufacturers—domestic and foreign—must comply with the regulations that go into effect on July 19, 2021. Products made before this date can be sold throughout the channel, and existing inventory does not need to be returned. However, all pumps made after this date must meet the new DOE energy efficiency criteria.
These requirements are based on a new metric named weighted energy factor (WEF). WEF is the first industry-wide efficiency metric and will naturally impact both international and Canadian markets as well. The new WEF rating will be physically labelled on most pumps imported into the market after July 19, 2021, which will allow users to easily compare energy efficiency to other models. As consumers are becoming more educated on performance and the total cost of ownership of a pump purchase, WEF is an easy way to evaluate and compare the energy efficiency of pool pumps and will cultivate a new standard for evaluating efficiency worldwide.
DOE-compliant pumps provide the same installation and performance requirements needed to successfully operate pools and spas while delivering significant energy savings and noticeably quieter operation, too.
Pool pumps often consume the second largest amount of household energy after heating and air conditioning and, as a result, have been part of pool efficiency measures for some time. The origins of WEF can largely be traced to the California Energy Commission’s (CEC’s) Appliance Efficiency Regulations, often referred to as ‘Title 20,’ that have been in place for pool pumps for more than a decade. While Title 20 prescriptively requires the type of pump motor used (two or more speeds for 1.0 total horsepower [HP] and above), it also requires manufacturers to provide data on each listed model including energy factor, which is the ratio of flow divided by power and where higher is better (more efficient). Energy factor is effectively how much water (flow) a pump can provide for a given amount of energy consumption.
The development of the DOE regulation started in 2015, and it was soon noted that energy factor, while useful, could be a misleading value as there are no limitations on how it is measured. For instance, it could be calculated at a speed that delivers an impractical flow such as 38 litres per minute (lpm) (10 gallons per minute [gpm]) or less. This led to the development of WEF, which is the weighted mix of energy factors at different speeds along with minimum flow requirements. The WEF for a single-speed pump is the same as energy factor, since there is only one speed at which to measure. For two-speed and variable-speed pumps (VSPs), WEF is weighted at 80 per cent of the low speed energy factor and 20 per cent of high speed.
Similar to other industries
Many other industries use minimum efficiency requirements and have, in turn, developed efficiency metrics that are a key factor in product selection. Notable examples similar to WEF are miles per gallon (mpg) for vehicles or seasonal energy efficiency ratio (SEER) for air conditioning units. Mpg is a vehicle’s efficiency and is calculated by dividing the distance driven by the amount of fuel consumed. The further one can drive on a tank of gas, the more efficient the vehicle. Air conditioning (AC) units now have a SEER calculated by dividing the amount of cooling produced (British thermal unit [Btu]) by the amount of electricity (watts) used. The more cooling produced by a watt of electricity, the more efficient the AC unit.
Both mpg and SEER are based on a standard set of conditions to assure consistency in measurements and, in turn, comparisons between products. This means the base product is efficient, but its actual energy consumption is determined by usage—the energy bill depends as much on what temperature one sets the AC as the SEER rating. Under the same conditions, a pool pump with a higher WEF will save more energy—and money—than a pump with a lower WEF. There is no doubt manufacturers will strive to improve their WEF efficiency ratings as product technologies and innovations continue to evolve and move forward.