Energy lessons from South Korea

Professor John Townend found himself at the epicentre of media attention and residents’ anger when he and other experts presented their findings into a magnitude 5.5 earthquake associated with deep geothermal drilling in South Korea.

Abstract animated image with various green shapes and shades.

John, a seismologist in Victoria University of Wellington’s School of Geography, Environment and Earth Sciences, was part of a team of five experts from China, New Zealand, Switzerland, and the United States, appointed by the Geological Society of Korea to investigate the earthquake for the South Korean Government.

The earthquake occurred in Pohang in the southeast of the country in November 2017. It injured 135 residents, displaced many people into emergency housing, and caused more than US$75 million in direct damage to more than 57,000 structures. Total economic impact exceeded US$300 million.

“The question we were asked to answer was whether fluid injection processes associated with deep geothermal exploration played a role in the earthquake’s origin. The answer we came to was an unequivocal ‘yes’, ” says John.

Presenting their findings earlier this year at a press conference in Seoul, John and his colleagues were met with “several hundred frustrated residents shouting and waving banners and placards, plus 20-odd TV cameras and untold photographers and reporters.

“The reason it’s been such a big deal is that the Pohang project was meant to demonstrate the feasibility of enhanced geothermal systems in South Korea as it weans itself off hydrocarbons and nuclear energy. There were no fatalities, fortunately, but lots of damage to buildings and infrastructure during the earthquake, and law suits are now being sharpened against the Government and various organisations involved in the project.”

As the research team has since outlined in an article for the journal Science, their findings provide lessons not only for South Korea—which shut down its geothermal exploration and carbon sequestration programmes following the earthquake—but worldwide.

“Operators and regulatory authorities need to do a better job of monitoring seismicity and need more comprehensive ways of evaluating the evolving seismic risk—and communicating that risk to the community,” says John.

He thinks the inquiry’s findings also highlight a wider issue of energy and the environment.

“Everyone wants to switch off from petroleum and to decarbonise as quickly as possible, but we also expect to sustain our high level of energy consumption.

“It’s vital to realise that swapping one energy source for another, or hydrocarbons for renewables, addresses only part of the problem. If we expect to continue using energy at current levels, then we’ll have to tackle questions of resources. Whether it’s silica for solar panels, lithium for batteries, or copper and neodymium for motors and turbines—which must be mined somewhere—our energy choices all have resource and environmental repercussions.

“We might think that going electric solves all our problems in one go; that’s not the case. Every energy technology uses resources and affects someone’s environment somewhere. They all have drawbacks and we should be looking at how we reduce energy use, not just changing our energy supply.”