A chart produced by Nordic Aquafarms compares the carbon footprint of the proposed Belfast facility, bottom, with a salmon farm operating today in northern China.


A chart produced by Nordic Aquafarms compares the carbon footprint of the proposed Belfast facility, bottom, with a salmon farm operating today in northern China.

Last December, a local engineer and a software developer released a speculative study of how the Nordic Aquafarms salmon farm in Belfast would affect the climate, concluding that it would be much worse than the company has advertised.

The study was written for Upstream Watch, Nordic’s most active and best-funded adversary, and the authors, Jim Merkel and George Aguiar, have been vocal opponents of the salmon farm. So the outcome was not a great surprise. But the study also cited reputable sources, used established methods for life-cycle assessment and generally showed its work, whereas Nordic has relied on expert endorsements. It concluded that the salmon farm would produce about 23 kilograms of carbon dioxide equivalents (CO2e, a greenhouse gas measure) per kilogram of processed fish. Nordic says that number will be closer to 5.3 kg.

So, which is it?

As with any set of disputed facts, the answer depends on how you measure and what you do with the results.

Nordic is still months away from breaking ground on the salmon farm, so any study is going to involve speculation. Further confounding the math problem, land-based aquaculture on the scale proposed in Belfast is new enough that the raw material of scientific studies is scant, and sometimes even hypothetical.

In a presentation to the Belfast Planning Board last June, Nordic said the Atlantic salmon produced here will have only 30 to 40 percent of the carbon footprint of salmon raised in Norwegian sea pens and shipped by air to the U.S. At full capacity, the Nordic facility would produce 33,000 metric tons of fish to be sold in the Northeast. Since air travel racks up a massive carbon footprint, the brilliance of Nordic’s proposal, both from an ecological and financial standpoint, lies in bringing the fish to the same side of the ocean as the people who are going to eat them. But raising water-breathing animals on land takes a lot of energy.

Nordic’s carbon footprint projections, according to Merkel and Aguiar, are based on a 2016 study that compared a hypothetical land-based salmon farm to a real Norwegian sea-pen facility shipping its salmon to Seattle. In that study, the land-based operation was found to use more electricity, but the sea pen business more than made up the difference in burnt jet fuel. In the end it wasn’t even close.

Aguiar and Merkel acknowledged this study (with a caveat that there are more sustainable sources of protein), but said a 2019 study using actual data from a land-based salmon farm in northern China paints a more accurate picture of what to expect in Belfast. That salmon farm had double the CO2 emissions of the hypothetical fish farm from the 2016 study. Though the result was still less greenhouse gas than the sea-pen and air-freight combination, it didn’t look as good for land-based aquaculture.

Nordic disputed the comparison, saying its Belfast facility would make one-third of the CO2 of its counterpart in China per kilogram of fish (Nordic 5.3 kg, China 16.7 kg). The salmon farm in the study, Nordic said, is less efficient than the Belfast facility would be, both in feed-related energy and operations; it relies on electricity from coal; and has longer transportation routes for eggs and feed: “Bottom line is that [Nordic Aquafarms in Belfast] is carbon-reversing compared to the current fresh fish model for the U.S.”

Nordic went on to say that the study was based on a life-span that is “much lower than modern [land-based] facilities.”

According to Merkel, that’s one of the major problems with Nordic’s estimate.

While Nordic assumed a lifecycle of 50 years, Merkel and Aguiar used 15 years, which Merkel said is consistent with the China study and accounts for the lifespan of equipment and the undesirable-but-real possibility that the business might fail.

“You use all your energy up front,” he said. “For a life-cycle assessment, you distribute it over the life of the project.

This up-front energy, known as “embodied energy,” includes everything that goes into construction, including the energy to produce steel, cement and other building materials and transport them to the site, along with fuel emissions from construction vehicles. It also accounts for the removal of CO2-sequestering trees and soil — in Nordic’s case, from a swath of a partially forested 54-acre site near Little River.

Responding to questions by email from California where Nordic Aquafarms is pursuing a second U.S. land-based fish farm, Commercial Director Marianne Naess defended Nordic’s projections.

“We have used our actual numbers in our assessment,” she said. “The problem with [Upstream Watch]’s study was not the model, but the assumptions they used.”

“… As any development, NAF’s farm will have some impact. This is not unique to our facility. Having said that, we have invested a lot in technological development to minimize any potential impact on the environment. We have credible expert witnesses who have testified to this at our hearings. You can look up testimonies from GMRI [Gulf of Maine Research Institute] and UNE [University of New England] at the DEP or the city webpages.”

In a written response to the Upstream Watch study, Nordic said its estimates are conservative. “Permit applications are made out to account for severe worst-case natural incidents,” the company said. The applications estimate using 900,000 gallons of diesel per year, while “… expected annual usage is less than 150,000 gallons per year. NAF also plans to use biofuel from Maine to reduce emissions.”

Nordic also took on a common complaint from opponents that the salmon farm is to be built on partially forested land and would be better on a former industrial site:

“If green-field developments are to be limited, it is reasonable to assess all existing land-use in terms of food yield, jobs, and economic development. The proposed farm from NAF provides higher yields, more jobs, and more economic development effects per acre than almost any food production in Maine.”

Merkel said he can understand why people would discount a study done by people who want Nordic gone. But the alternative, he said, would be to rely on assurances from Nordic Aquafarms, which he believes are even less likely to be reliable. “They’re the applicant,” he said. “It’s 100-percent biased. Their data is not data, it’s designed.”

At best, he said the company is looking through rose-colored glasses.

“You have to be devil’s advocate,” he said. “You have to be a skeptical engineer, so something works when you’re done.”