Maui matters. It matters to Maine and probably many other places.
That’s because Hawaiian Electric, the utility that serves the island, has become the focus of concerns that it was a major cause of the fires that disastrously swept a part of that Pacific island. The utility’s downed wires probably caused extensive fires that were not doused quickly enough.
Electricity customers almost everywhere get periodic warnings not to touch wires that are off the poles, usually as the result of a storm. Wires carry electricity from power generators to end-use customers for use in heating, machinery, lighting and many other devices. If they touch the ground, they may remain live and carry power to anything or anyone who touches them.
Anything an energized line touches receives electricity. In Maui, lines were downed and set off uncontrolled fires on the ground. The fires took what may prove to be hundreds of lives, and critics claim it could have cut off power sooner. If a person touches a live wire that is disconnected from its usual path, they can conduct power on the wire.
One reason why the threat of downed lines exists is because most electric wires are thin and bare and not protected by an insulating covering. That means that if they come under the weight of a tree limb or fallen tree, they can break more easily than would a more substantial, insulated wire.
Where lines are relatively often broken or grounded, power to customers is interrupted. These “outages” lead to a loss of reliability.
Like Maui, Maine may be unusually vulnerable. More of its surface is forested than in any other state. Utilities claim that trees are the reason why Maine has among the highest rate of outages of all states. Central Maine Power and Versant are among the least reliable electric utilities in the country.
But there’s a lot more to this story. There have always been trees in Maine, and the utilities should have considerable experience with them. Central Maine Power has existed since 1910, 113 years ago. Couldn’t it have learned to deal with trees at some time?
The Maine Public Utilities Commission and similar regulators in other states require utilities to keep vegetation away from causing outages. The rates they’re authorized to collect include the costs of “vegetation management.” If a utility scrimps on tree trimming, it can keep as profit some of that allowed income.
That may have happened on Maui and in other utilities across the country. It can be detected in states where there are both high outage rates and lots of trees.
Unless regulators keep a sharp eye on utility tree trimming, outages can be excessive, making the system unreliable. A few years ago in Maine, the PUC finally induced CMP to adopt a program of vegetation management to get trees away from the lines and increase reliability. In other states, other utilities did the same.
“We decided that we needed to get very serious about doing tree trim along every mile, along every span of our distribution system, so we started that in 2008 and gradually over the years — since the program started — we’ve been seeing more and more of a reduction in outages caused by trees,” said CMP.
CMP took credit for what it was finally required to do, only 98 years after the utility was founded. And still its outage rates are among the highest.
There’s another solution that yields maintenance savings: protect the wires. Wires can be insulated and supported by metal cable, avoiding expensive underground lines. But that investment may be less profitable for the utility than building major transmission lines.
Maine, only the 39th state in size, is supposedly too large to use protected wires. But about half of the state’s territory is unorganized with virtually no utility electric service at all.
Nonprofit utilities have no incentive to skip tree trimming to boost their revenues. Admittedly, Nebraska has few trees compared with Maine, but it’s also the only state with no for-profit utilities. It is ranked as the most reliable state for electric service just about every year.
The issue may be less about the trees than about the utility. For example, Louisiana joins Maine at the bottom on reliability and it has above average tree coverage. It is dominated by a for-profit utility. In contrast, Maine’s nonprofit utilities are more reliable than the state’s two for-profits.
A disaster such as occurred in Maui can happen elsewhere. Look at PG&E’s forest fires in California. It could happen in Maine.
The answer is either regulators at last getting tougher on for-profit utilities by requiring them to install protected wire or giving the responsibility to nonprofit utility management, like the proposed Pine Tree Power, accountable only to its customers for their safety and reliable power.
Gordon L. Weil formerly wrote for the Washington Post and other newspapers, served on the U.S. Senate and EU staffs, headed Maine state agencies and was a Harpswell selectman.
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