Magnetism in battle to cut carbon emissions

| Victoria Klesty, Simon Jessop and Barbara Lewis 21 May 2019

In the cavernous chamber of Norsk Hydro's aluminum smelter on the Norwegian island of Karmoey, the magnetic force is so strong that heavy iron wrenches float out of the hands of workers.

The firm is piloting a technology that tames the effects of that powerful magnetic field that flows from the electrolysis to make aluminum and leaches away energy.

It is using mathematical models to mitigate the effect of the magnetism and other energy waste. The pilot project can cut the amount of energy used in production by 15 percent compared to the industry average.

The technique is one of the drives it is banking on to make good on its ambitious pledge to become carbon neutral by 2020. The industry is under increasing pressure by investors and governments formulating carbon taxes to reduce CO2 emissions.

"If aluminum is to be a material for a low-carbon future we have to defend it by having as low emissions as we can," chief executive Hilde Merete Aasheim says in Oslo. "This is where the Karmoey project will play a part, developing technological elements that can be used in other plants to bring down energy consumption."

Its pilot used between 11.8 and 12.3 kilowatt hours of energy per kilogram of aluminium. It says the 11.8 figure is a record low for the industry, which averages 14.1.

There is a long way to go before the plans are likely to have a major impact across Norsk's business.

The pilot project at Karmoey alone required an investment of 4.3 billion crowns (HK$3.84 billion) - roughly equal to its net income last year, though about a third of that is being shouldered by state investor Enova.

The scheme is still at an early stage, with a capacity of 75,000 tonnes of aluminum per year, a fraction of Norsk's annual production of about two million tonnes.

Hitting carbon-neutrality also depends on other measures, like increased recycling.

The tech drive has come at a time when Norsk has been under financial and reputational strain. It is reliant on Brazil, home to its largest alumina refinery, where a spill of untreated water into a river last year forced it to halve plant capacity, dragged on its share price and tarnished its green credibility.

Norsk is not alone in the green race.Giants Alcoa and Rio Tinto set up a venture last year that is developing a smelting process that emits oxygen instead of greenhouse gases, using a ceramic anode instead of a carbon anode during electrolysis.

While Norsk is among the top 10 producers in the world, it is dwarfed by firms like China Hongqiao and Russia's Rusal.

But it is the industry leader when assessed across environmental, social and governance issues, says Sustainalytics. Much of this, though, is down to the firm being based in Norway, where hydroelectricity - favored by most firms as the cheapest way to produce aluminum - is abundant.

Typically, energy accounts for a third of production costs, so cutting energy input makes economic and environmental sense.

Simon Webber of Schroder ISF Global Climate Change Equity fund, a Norsk shareholder, says: "The most-efficient producer, or lowest-emission producer, which is Norsk, will be very well placed for that."

But there is contention over Norsk's pledge to be carbon-neutral from next year.

Some green campaigners dismiss the pledge due to the method it uses to measure net emissions. It will not just include its own emissions but also emissions avoided by the greater use of aluminium in cars to make them lighter and use less fuel.

The problem is, it would be better for the environment if everyone drove less.

"Every company looks to claim their products are a solution," says Nate Aden, a senior fellow at the World Resources Institute, which helped develop the Greenhouse Gas Protocol for counting emissions.


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