Why and how to electrify aquaculture
If we electrify Norway’s salmon farms, we can save some 375,000 tonnes of CO2 per year, which is the equivalent to the annual CO2 emissions from 200,000 cars.
That’s according to Benjamin Strandquist, Senior Advisor on Electrification across sectors such as construction, shipping, aquaculture, industry and land-based transportation at the Norwegian environmental NGO The Bellona Foundation.
“These are emissions cuts that are significant and we can achieve them with technology that is already there,” Benjamin says in an interview with EngageWithOceans.
“We need to electrify our shores and this is part of that process.”
The electrification will take place on two fronts, namely at the fish farms themselves and of the fleet of boats used by the sector.
Shore power and beyond
The first challenge will be to stretch power cables from the shore across the seabed to the salmon cages. There has been considerable progress in recent years, Benjamin notes. Currently, some 57% of Norway’s salmon farms are connected to shore power, he says.
“There is a lot of emphasis on feed, there is a lot of emphasis on transport emissions, and we feel that the production phase of salmon production shouldn’t be overlooked,” Benjamin says.
“On the [remaining] fish farms, there is usually a diesel generator running to operate the feeding and to operate the machines used to clean the cages. They have a very high demand for power.”
The majority of Norway’s sea-based aquaculture can be electrified with technologies such as electric cables to shore, while the remainder will require alternative solutions that rely on energy carriers such as hydrogen or ammonia in combination with fuel cells, or on batteries.
“If you have a fish farm that is located in such a way that you cannot connect to the grid without it costing way too much, or it’s just not practically doable, we need to maybe in a transition phase think of hybridization. You can install battery packs and as such use the generator much more efficiently,” Benjamin says.
“Right now, if you have just a generator without a battery, there is a lot of wasted energy during periods of low activity on the fish farm. But in a few years, we will have more market-ready solutions with hydrogen or ammonia in combination with fuel cells, which can then replace those generators and be refueled from boats.”
In theory, electrifying salmon farms is relatively easy. “If you can connect the fish farm to shore power, you can skip the diesel generator entirely, and thus cutting all those emissions,” Benjamin observes.
“We’re using standard components for this. Standard cables and standard equipment that is readily available today. You just need to put it into this system.”
Norway produces almost all its electricity from renewable sources such as hydropower and wind farms, so the impact in terms of emissions cuts would be instant. In practice, however, the process fish farmers must go through to electrify is not always simple.
“You need to have power in the vicinity onshore, and you need a grid company to cooperate with you. They may not be super willing to help you with that cable. So in order to electrify, you need to reach out as soon as possible to the local grid company, tell them about your plans and start a dialogue about the best way to go about things,” says Benjamin.
“You might also want to use batteries where you cannot get sufficient power from shore, but you can get some power,” Benjamin says.
“Use whatever you can get and combine it with batteries that you can trickle charge. Use those for peak shaving when you need the most energy during demanding operations.”
Boats are the second major source of CO2 emissions from the aquaculture sector.
“Less than one percent of the boats in daily operations around fish farms in Norway are electrified in one way or another. That is one area where we will focus a lot of our attention,” says Benjamin.
“About two-thirds of emissions came from the farms and the last third from the boats, but with the remaining emissions to cut, a little over half is related to boats.”
There are now several companies that make electric boats or convert boats from diesel to electric. Charging stations can be fitted at electrified fish farms in addition to along the shore.
So electric boats can be a practical alternative, though obviously, farmers want to make sure they do not run out of power while at sea.
“Farmers may in certain cases want a buffer, such as a diesel-electric hybrid solution or an emergency backup system, such as a diesel generator that can be used to recharge batteries in case of emergency,” says Benjamin. “The goal is of course to make diesel backup solutions obsolete through improvements in technology and the deployment of fuel-cell based alternatives.”
Electrifying fish farms obviously has a cost attached, but although the fish farmers “have to foot the bill initially, it usually pays for itself in a one-to-three years timeframe in our reference projects”, Benjamin observes.
The same may well be true for boats, but in many cases the farmers “haven’t looked at what the upfront cost will be, how long it will take to pay off”, Benjamin says.
“Usually, if you have a boat that is in daily use, it is going to be economically feasible.”
The government should also play a role, he insists, urging ministers to be “gentle and strict at the same time”.
“Governments should make a cohesive regulatory environment, set some deadlines for the phase-out of fossil fuels, as well as establish some support schemes to make it happen,” he says.
Norway’s aquaculture exports bring in some 100bn kroner ($11.6bn; €9.9bn) per year, and the industry predicts this to multiply over the next decades, so it is essential to make sure this growth does not result in a sharp rise in CO2 emissions.
“The industry also has an interest in doing this because it helps improve the public’s image of farmed fish that is being produced without emissions in the sea,” Benjamin says.
“In the end, it’s going to be more expensive to sit on the fence and wait because new restrictions, new emissions cuts demands, will appear and if you’re then lagging behind in your electrification, you’re going to be in a rush. And being in a rush is expensive.”
Sustainable food production
Cutting emissions from aquaculture will help make fish farming a truly sustainable way to produce protein for the world’s fast-growing population.
“The carbon footprint of fish farming is [already] very low when compared with onshore meat production,” Benjamin points out.
“We have a strong belief that fish farming is the sustainable way to go forward, but we need to fix the associated problems and challenges.”
Once solutions have been developed and proven at Norwegian fish farms, they can be applied across the world.
“This should be applicable in most places where we farm fish, so the idea is that when we find good solutions, good ways to go about electrification projects, we export them,” Benjamin says.