LG&E heralds hydro revamp as broader clean-power fight looms

The boost in generating capacity is almost entirely thanks to the design of the new, propeller-like “runners” installed at the plant, officials say. | Courtesy of LG&E

LG&E this week is celebrating the overhaul of its 91-year-old Ohio Falls hydroelectric plant, just as the utility and clean-power advocates gird for a possible restart of a skirmish over state clean-energy rules.

Utility officials say they spent about $148 million over 13 years to replace all eight generating units and runners — the propeller-looking devices spun by falling water — and to redredge the adjacent riverbed, update technology and spruce up the building. The result of the work, finished in November, is a boost in generating capacity from 80 megawatts to around 100 megawatts, when river conditions are just right.

“The first units lasted almost 90 years,” said Kerry Johnson, production supervisor at Ohio Falls. “With all the technology that went into this, with the stainless steel versus cast iron, with all the changes they’ve made, these units should last a hundred years, easily.”

Johnson said the revamped plant at its best can power downtown Louisville or the equivalent of 72,000 homes.  

Kerry Johnson, the production supervisor at Ohio Falls, explains how an emergency bulkhead would be used. | Photo by Mark R. Long

Small sliver of the energy pie

Along with the Dix Dam hydro plant and and 10 megawatts of solar power at E.W. Brown in Mercer County, the Ohio Falls plant on Shippingport Island supplies pollution-free power for a utility otherwise dependent on gas and coal-fired generation.

LG&E and KU say more clean power is in the works. The company, a unit of Allentown, Penn.-based PPL Corp., has a small subscription-based solar project under way near Simpsonville, and expects to issue a request for proposals for renewable energy by month’s end, a spokeswoman said. Officials also say the utility is cutting emissions of heat-trapping gases as it shifts from coal to gas-fired power, like at its big Cane Run facility.

Environmental groups, solar-power companies and other clean-energy advocates say these efforts from LG&E and other utilities fall short of what’s needed to fight climate change, and are urging politicians and businesses to act more quickly.

Groups here are pressing metro lawmakers to commit to abandoning fossil fuels and set a goal of 100 percent renewable-energy use by city government by 2030, and by the entire metro area by 2035.  Louisville government last month set a target to cut greenhouse-gas emissions 80 percent by 2050.

Clash over power from sun

Kentuckians get just 0.1 percent of their electricity from solar, with about 4,100 homes powered by panels, according to the Solar Energy Industries Association.

Nevertheless, a fight over how utilities compensate homeowners and small businesses who feed solar power back into the grid dominated state energy politics in 2018. A bill that would have cut the payback from “net metering” didn’t pass, but people on each side of the argument say the issue could be revived in Frankfort, perhaps as soon as the current legislative session, which resumes Feb. 5.

Leaders of the House and Senate, and the chairman of the Senate Natural Resources and Energy Committee, didn’t respond to messages and emails seeking comment. Rep. Jim Gooch, R-Providence, the chairman of the House Natural Resources and Energy Committee, sponsored last year’s bill. He said Wednesday that he didn’t plan to carry a net-metering bill this session, but continues to support changing the rules.

Citing a range of government and private studies, and utilities’ own numbers, solar-power backers say the cost to ratepayers is very small — even if net-metered solar reaches a cap of 1 percent of a utility’s peak load.

“It should be a non-issue,” said Andy McDonald, the director of sustainable systems programs for Earth Tools Inc., and a longtime renewable-energy advocate. Net metering “works well for the people who want to use it and to see it threatened is just frustrating,” he said, adding the 1 percent cap allows utilities to hit the brakes long before net metering threatens the resilience of the grid.

Still, even though the amount of money spread to utility customers is tiny, “I don’t want them paying even a fraction of the costs for someone who can afford it,” Gooch said.   

LG&E officials also said they remain in favor of changing the rules. “What we were trying to do with net metering was ensure the cost was equal for everybody,” said the spokeswoman, Chris Whelan.

Workers completed construction of Ohio Falls in about three years in 1927. | Courtesy of LG&E

Down by the river

On a recent tour of Ohio Falls, the broader arguments over renewable energy were drowned out by the rush of river water. The swollen Ohio was too high to run the generators — a fact LG&E officials took pains to explain.

The McAlpine Locks & Dam splits the river into two pools, upper and lower. Water falls down from the higher pool to spin the LG&E plant’s runners and generate power. The natural, horizontal flow of the river isn’t strong enough.

“It’s not like a boat propeller,” said Dave Tummonds, general manager of Cane Run and Combustion Turbines, who also oversees Ohio Falls. “It really does run primarily off the differential between the upper pool and the lower side.”

The Army Corps of Engineers runs the dam complex, and it has to keep water levels optimal for barge traffic and flood control. LG&E’s needs come last.

This means the hydro plant can’t run 30 to 40 percent of the time, said Johnson, the production supervisor. Yet even with the expense of the revamp, the nearly free fuel of the water means it makes sense for LG&E to run the plant whenever it can.

Much of what was built in just three years in the 1920s remains at Ohio Falls, in use for the better part of a century. The jump in capacity is thanks almost entirely to the computer-guided design and machining of the propeller-like runners, officials said.

“A hundred years ago you had really brilliant people taking their best stab at things,” Tummonds said. “Now, you’ve got machines doing five billion iterations and optimizing the design.”