Ground current plagues Ontario farms says electrical expert
Tuesday, December 4, 2012
by BETTER FARMING STAFF
In June, 2009, the Ontario Energy Board directed power distribution companies to take specific steps to mitigate stray voltage issues on farms and the agricultural community celebrated.
Now, some farmers and experts say those efforts aren’t helping, and charge that some situations are worse. That was the message to more than 100 farmers gathered in Listowel last week. The meeting, run by the Ontario Federation of Agriculture, was the first of several that the federation plans to organize across the province. (See correction below)
In 2009, the energy board set the maximum neutral to ground earth voltage at no more than half a volt. Previous to that, the Ontario Electrical Safety Code Rule 75-414 established the maximum neutral to ground earth voltage as 10 volts. Utilities were required to mitigate voltages above that. Problems with volts below 10 V were the responsibility of the customer.
But voltage isn’t always the issue, Wellesley consultant and former dairy farmer Lorne Lantz says. The real issue, Lantz says, is amperage and the directive doesn’t address that. (Voltage is the force that motivates electrons to flow; amperage, or current, is the electrons’ flow rate).
The energy board’s directive came in the aftermath of former Lambton-Kent-Middlesex MPP Maria Van Bommel’s private members bill called the Ground Current Pollution Act. While the bill passed two readings with the unanimous consent of all political parties, it never became law, but nonetheless got the attention of the energy board.
Lantz points out the distinction between ground current and voltage. “Somewhere along the way it got side-railed,” he says. If distribution companies investigating problems on a farm are measuring only voltage “they are looking for the wrong thing.”
Furthermore, he says, utilities have been trying to meet the directive by putting more ground wires on the poles carrying power down the sides of rural roads. “Now they are grounding every third pole,” meaning more current is going into the ground.
Lantz says grounding on primary neutrals is the issue. Utilities must be responsible for the uncontrolled return current entering into private property without permission or compensation. Utilities must be responsible for their uncontrolled ground current that is in the earth affecting livestock operations across Ontario.
“Farmers are responsible for cleanup of any manure, chemical or field spills at their expense,” he says. “Utilities dump their return current in the earth and no one says a word.
“If we could see the current that is in the ground and see the result of what it is doing compared to a fuel spill that is in a creek and there are a few dead fish there would be a lot of people hollering.”
“It is the current that does the damage, not the voltage,” says Lantz. He cited a case of Allen Erb’s dairy farm near Wellesley (Better Farming, October, 2010), where extraordinary measures were taken to shield the farm buildings from ground current. Lantz says current in the barn was reduced from nearly 10 milliamps down to 1.3 milliamps. The somatic cell count, a universal measure of milk quality, fell to below 250,000 from a penalty triggering 600,000. Open sores on cows “cleaned up and we greatly reduced the cases of new mastitis.”
The influence on livestock goes well beyond cattle “but we have the best information” on dairy cattle, says Magda Havas, a Trent University professor.
Ground current tends to be an issue with expanded operations, so it is with farming operations that are successful. Havas described the effects of ground current as “very active biologically.” In cows it affects the mammary glands, and the ovaries as the current may flow from one hind leg to another. But it’s not restricted to cows. Sometimes pig and poultry operations are affected as well.
Typically, affected farmers are “very good dairy operators," she says. "They do so well that they built a new shed or put in a new barn . . . once they have moved away from a wooden structure to a metal structure and they have really, really, good grounding, what they are actually doing is they draw the current to their farm and that’s when the problems happen.”
“This is not a problem they can resolve on their own farm without making it worse for their neighbours,” Havas says. “It has to be solved at the source. If this is a distribution problem it has to be dealt with by the utility.”
Lantz says the state of California doesn’t allow power distributors to send their primary neutral current into the ground. There is a four-line system with a primary line and a primary neutral and he proposes that be brought into place in Ontario.
John Kalich, manager of Hydro One’s distribution planner, based in Barrie, was at the Listowel meeting but did not make a presentation. He described some of the comments made at the meeting as “fear mongering” and described a general “hostility” towards Hydro One. He says power distribution companies are grounding at multiple poles not to save costs, as was alluded, but because that is what they have been directed to do by the Ontario Energy Board. “We have a multi-grounded system, not to save money but because that is way the system is designed and has been from day one,” Kalich says. BF
Correction: The meeting was sponsored by the Perth County Federation of Agriculture. The Perth federation has no plans to repeat this meeting elsewhere in the province.