See how liquid bird repellent helped eliminate pest birds around electric substations in this article by BirdBuffer LLC.
Several years ago, Pacific Gas & Electric engaged in an endeavor to find a better solution to keep birds out of their substations in California. An article written by Kellie Collins, Steve Yonge, and Ron Critchlow of the San Francisco Pacific Gas and Electric Co, discussed the problems birds create when gathering together in large flocks at substations. This is a recap of their findings.
When birds gather together in large numbers, they can create hazardous situations with their droppings, including damage to buildings and equipment, risk of outages that cause capacitor banks to suddenly fail, creating reliability problems for customers and making maintenance very difficult and expensive. Failures can shut down power for parts of a city and cause the entire substation to have to be shut down and repaired. Bird droppings can also cause a transformers to short or explode, creating even larger problems and safety issues for anyone working in the substation.
The annual cost today for maintenance of bird cleanup and repair is approximately $300,000, not including health risks that can put workers on compensation or disability. The key is to find a solution that is long-lasting and is not going to be overly expensive.
In the past, maintenance workers have used many methods to try to keep birds away. Shelter and warmth attract birds to substations, and birds travel in flocks. Even if flying birds see one bird at a location, they are motivated to join them. As a large flock of birds remains in one location for a period of time, their droppings start to accumulate and draw in more birds.
Bird droppings contain cause considerable damage to metal and wires. Birds carry over 80 different types of disease which can cause health issues for workers. The sight of bird droppings will attract even more birds along with other animals. When birds fly over an area that has an accumulation of droppings (even if they don’t see other birds), they feel secure about visiting that location. As time goes on, they start to nest and lay eggs. To complicate the situation, some birds, especially crows, are very protective of each other’s nests. As soon as a crow calls for help, there will be a flock of fighters that come to protect them. This of course, immediately expands the amount of birds in the area of the substations.
At PG&E, the utility personnel tried a variety of options to try to chase the birds away, but they kept coming back. Ultrasonic deterrents, cannons, and air horns only scared birds away temporarily. Decoys like owls were useless. When these methods failed, PG&E decided to investigate all types of bird repellants, mechanical and chemical, before investigating a liquid made with a grape juice extract, called Methyl Anthranilate (MA). This product was being used by farmers to spray on grapes, cherries and blueberries to stop birds from eating their fruit crops. The farmers sprayed the MA on to fruit harvests just as the birds were starting to come to eat the ripening crop. The birds soon found that the fruit was not good to eat and farmers were able to increase crop production significantly. Unfortunately a spray was not the best answer for electrical power lines, so a dryer application would need to be created.
Soon after, a fogger was used to heat the liquid Methyl Anthranilate (MA) and convert it to a thick cloud of fog that was sprayed into the air by an operator. As the fog passes over the area where birds were roosting or nesting, the scent causes an uncomfortable but harmless reaction in the bird’s trigeminal nerves which causes them to leave the area. It appeared that the birds did not get used to the smell, but for some reason, they continued to return as soon as the fog left the area. Repetitive fogging kept the birds away longer each time it was applied. It was determined that the vapor isn’t harmful to humans, animals or the birds, and had recently been approved by the EPA. Methyl Anthranilate (MA) is classified with the FDA as GRAS or Generally Regarded As Safe, and USDA had approved it for bird control.
Collings, Young, and Critchlow determined it should be tested with high-voltage situations to see if there could be any negative results:
To determine how it performed on 500-kV substation equipment, PG&E tested it on capacitors and insulators in a controlled environment using two different delivery systems. First was a blower with a misting element and the second applicator was a handheld thermal fogger. Both were used to apply the MA to capacitor banks and high-voltage insulators during dry and wet conditions.
The electrical and chemical tests demonstrated that multiple applications did not jeopardize the integrity of equipment. Test results showed:
1. Direct spraying of the capacitor banks did not cause arcing or flashover, and no significant increase of the leakage current was measurable
2. Mist or fogging had minimal impacts on the corona present at the 115-kV post insulator
3. No arcing or flashover of the equipment was created by the application from either the mist or fog applicators
4. No arcing or flashover was observed, and leakage current from the equipment applicator handle to ground was insignificant (0.01mA)
5. No significant residue remained on the equipment and contamination levels were clean, based on EPRI’s contamination-grade continuum.
Given the positive results of the controlled tests, PG&E chose its Table Mountain substation, near Oroville, California, for a field test. Table Mountain is a 500-kV substation located in a rural setting with no nearby residential development. Historically, the substation’s four 500-kV series capacitor banks have been the preferred fall and winter roosts for large numbers of birds, including: European starlings, Brewer blackbirds, house finches and English sparrows.
The test began using a hand held thermal fogger (Gold Eagle brand) with a 40-hp to 45-hp pulse-ram jet engine, capable of directing the plume (of fog) toward the capacitor banks. This very loud unit used approximately one to two gallons of MA fluid per application and created a plume of thick fog that was very unpleasant to smell. Timing of the applications was during the return of the birds, so evening hours were chosen. Fogging was applied during the evening as birds were returning to roost. Prior to each application, the number of birds were estimated by visual counts and appeared to be reducing with each application. But after a period of time, the birds began start to return.
The results were impressive, but continued manual applications were time consuming and expensive. The birds would leave, but later return after requiring continuous application. This was very labor intensive and required constant attention.
On January 9th, 2013, PG&E contacted a company called BirdBuffer LLC to test a new product that did not require manual operation or spraying. It used the same MA fluid, but the equipment created a dry vapor that was less visual to the birds, less pungent, very quiet, much farther reaching, and had an automated system with clocks and timers that could easily be adjusted to the needs of the particular application site. Once per month a 15 minute maintenance was required to refill the fluid and change a filter. It only used one gallon of Methyl Anthranilate per month instead of one gallon per hour, thus saving thousands of dollars.
Two BirdBuffer® machines were placed at the Table Mountain substation for a three month test run to determine efficacy. After only one month, Rick Fritz of Table Mountain stated that most of the birds had gone. He said, “Bill (the pigeon) is still hanging around with Betty (his pigeon mate) at the top of the tower, but they keep moving further away. I can smell a light hint of grape almost ½ a mile away. It’s really working.” After 3 months of operation, the birds did not return and he stated, “There isn’t a bird within a mile of this location.”
Prior to the initial application, the number of birds roosting in the capacitor banks was estimated between 50,000 and 75,000. Finding a method of reducing this to near zero, was a considerable success. Not only did the BirdBuffers rid the substation of birds, but employees no longer had to clean-up bird droppings, feathers, and nests.
It was initially reported that the Table Mountain substation was an ideal bird-roost site, because grasslands and agricultural fields provided a habitat for starlings surrounding the area. As a result of this testing it was determined that the continuous on/off release of the vapor, created a “learning environment” for the birds. A “scout” bird would return to the area and experience the irritating feeling caused by the invisible vapor. This constant testing of the area by one bird (the scout) can go on for months, even years. Because of this, keeping the machine full of fluid and operational is very important.
Savings in labor and fluid product as well as the absence of any potential disease was remarkable and there was a noticeable increase in the moral of all the workers. Normal repairs were also reduced dramatically, and the annual cost to clean of $300,000 was reduced to zero. A return on investment showed payments were returned 3 fold at the end of just 6 months, and returns continue to be counted as time goes on. Once the birds stopped frequenting the site, the BirdBuffer output was reduced to one gallon per every other month, rather than every month. This creates even higher ROI and the only time required by staff is 15 minutes and one gallon of the fluid every two months. This resulted in 6 visits per year, for a total of 1.5 hours of labor, 6 gallons of fluid, 6 filters and very high results.
After two years without any birds returning, PG&E decided to purchase an additional 16 machines for many of their substations. Using a combination of clean-up strategies and the BirdBuffer, PG&E achieved ultimate success.
For more information on invisible protection with visible results, contact BirdBuffer LLC at (425) 697-4274 or visit www.birdbuffer.com.