All waterbodies, whether small retention ponds or large-acreage ponds and lakes, benefit from increased dissolved oxygen levels provided through aeration. While ponds receive some aeration simply through water movement created by nature, it is not enough to optimize the health of the waterbody for aquatic life and rid the water column of toxic gases that build up over time. Therefore, pond owners should always consider maximizing aeration through the use of decorative fountains, surface aerators or diffused aeration systems.
Decorative fountains and surface aerators typically aerate 6 to 8 feet deep and provide some aesthetic value. Diffused aeration systems, on the other hand, provide whole-pond aeration through subsurface water movement that begins at the pond floor. Regardless of which type of system a pond owner chooses, a few other factors may determine whether water aeration powered by renewable energy or traditional electric provide the best fit.
Solar: A Renewable Power Source for Water Aeration
One renewable power source for water aeration is solar. Solar-powered fountains and aerators have become more popular in recent years due to improved photovoltaic (PV) technology as well as their ability to provide aeration for ponds in more remote locations where access to electricity is either limited or nonexistent. Solar-driven fountain and aeration systems can be installed virtually anywhere, provided the system can receive optimal southern exposure and is free from obstructions such as trees and vegetation growth, privacy fences or buildings.
Given that solar panel mounting equipment can often be installed pondside, some cost savings can be achieved on power cords for fountains and on airlines for diffused aeration systems. The savings on these items, however, only equates to a fraction of the cost of solar-powered equipment, which is typically 2 to 2 ½ times the cost of a traditional electric system. Therefore, the average return on investment occurs between years 6 and 8 of run time on a solar unit. Conversely, even if electric power is possible in some remote locations, the costs involved in running power to the desired location can often exceed the overall price of a solar unit.
Wind: An Unreliable Renewable Power Source for Water Aeration
Some have turned to the use of windmill aeration when looking to improve pond health, believing it to be a comparable, less expensive option to solar; however, this is not the case. Windmill aeration is wholly inconsistent, given that it is completely dependent on natural air movement, which can vary by the hour. Wind levels often decrease at night and in the hottest parts of the day, when aeration is most critical.
I have often been disappointed with the performance and results of wind-powered systems. Well-designed solar powered systems provide consistent aeration, even under cloudy conditions, and can run up to 12 hours per day on direct-drive systems, providing supplemental oxygen during the hot summer months while also preventing winter fish kills.
The only downside of a direct-drive system is that as daylight hours decrease in winter months, so do the hours of operation. A premium solar aerator with battery backup can provide aeration for up to 24 hours per day, providing all the same benefits, plus increasing oxygen levels at night and providing more consistent enhancement of beneficial bacteria treatment products. Therefore, when truly concerned about improving the water quality of ponds in more remote areas, solar is the only viable option.
Limitations of Solar-Powered Water Aeration
Despite the flexibility and green energy benefits of solar fountains and aerators, they do have their limitations. Solar fountains and surface aerators, which are also direct-drive units, are unable to run at night during times when aeration is needed most, since aquatic plants only give off additional oxygen during daylight hours through photosynthesis. The same goes for direct-drive solar aeration systems — although this could be resolved with a slightly more expensive battery-backup aeration system.
Nevertheless, pond depth and size are defining characteristics that could potentially eliminate diffused solar aeration systems from the list of options altogether, given that the typical solar unit has a maximum diffuser depth of around 20 feet. Most traditional electric aeration systems are designed to operate at a depth from 2 to 50 feet and allow for aeration in even the deepest part of a pond, with an average operating cost of approximately $1.25 – $1.50 per day.
Larger waterbodies over two acres are also ideal candidates for electric-powered aeration systems since they can often be sufficiently aerated with one system powering anywhere from four to 12 diffusers. Aerating the same pond with solar would require multiple units, increasing the equipment costs to 3 to 4 times that of a single large electric-powered system.
The Electric Advantage
Systems powered by electricity also have distinct advantages and limitations to consider. Advancements in compressor technology have significantly reduced electricity consumption, making electric-powered aeration systems both energy efficient and cost effective.
Electric aeration systems are the most reliable option for most pond and lake owners. Consistent performance ensures a steady supply of oxygen, improving water circulation and overall water quality. Like solar and wind-powered aerators, electric diffused aeration systems can be used year-round, regardless of weather conditions; however, they are not dependent on unpredictable factors such as sunlight or wind gusts, resulting in the most consistent aeration throughout all seasons.
Electric aeration systems are known for their ease of installation, as most systems run on standard 115-volt power. This convenience allows for a hassle-free setup, saving time and effort. Systems are available in various sizes to meet the needs of waterbodies large and small, deep or shallow. Electric aeration systems do, of course, require a power source nearby. If pondside power is not available, most electric aeration systems can be placed up to 1,000 feet from the shore using a remote manifold. If you have a remote pond with no access to electric power, alternative energy sources should be considered.
Similar to aeration, if you have a remote pond or prefer alternative energy, solar-powered fountains are a good choice. Electric fountains, however, offer a wider variety of horsepower options, producing unrivaled displays in height and scale. Fountain choice largely depends on aesthetic goals and available power supply.
Deciding on the right option
For the majority of small-to-medium-sized natural waterbodies, solar-powered fountains and aerators can greatly improve water quality by removing toxic gases, increasing dissolved oxygen levels and enhancing the performance of natural bacteria treatment products, especially when traditional electric power is not available. They also present an alternative for those who simply prefer a green-energy solution to improving pond health. Although a traditional electric-powered fountain or aerator will always provide a wider range of system options, the most consistent performance and the lowest initial investment cost, solar fountains and aerators have secured a place in the pond and lake market through continued improvements in solar technology.
About the Author
Scott Finn has been the technical training manager at Airmax since 2020. In 2018, he developed the Certified Airmax Service Technician (CAST) program, a service school that allows professional installers from around the country to become certified experts in the installation, maintenance and troubleshooting of Airmax fountains and aeration systems. As a part of the Airmax Product Development team, Scott is directly involved in new product launches through product testing, training and development of technical product information.