Call them the “moon shot” promises. The big, bold corporate sustainability targets that take your breath away, and may scramble your trust as well.

Can Apple really cease to depend on mining for any of the metal in its products, a goal it announced (pdf) in April?

Surely Walmart’s Project Gigaton to eliminate a billion tonnes of carbon dioxide from its supply chain by 2030 is a pipe-dream?

And who is Unilever kidding when one of the world’s biggest purveyors of palm oil products says it will stop causing net deforestation by 2020?

It is easy to be cynical. Apple admits it doesn’t yet know how to cut the mining cord. Unilever’s charismatic CEO Paul Polman has been caveating that deforestation promise (pdf) as 2020 approaches.

And as for Walmart, since farmers, processors and manufacturers are responsible for most of the emissions in its supply chain, the retailer’s climate goal – the equivalent of eliminating the annual emissions of Germany – depends overwhelmingly on putting the squeeze on them.

Glimpsing the future

But we all need a star to steer by. Aspiration is good even when the route is unclear.

The prospect of achieving these goals will be helped by the fact that many global megatrends are already moving in the same direction. Three-quarters of the world’s aluminium is already recycled, so Apple’s promise to reach 100% in its own operations is not so far-fetched.

And in the past three years, the global economy has grown 9% without any rise in CO2 emissions. In 2015 the world invested twice as much (pdf) in renewables as in new coal and gas power generation.

Whether corporations are the driving force, or simply hitching a ride, is open to question. But some at least have glimpsed a new future of low-carbon energy, resource-efficient agriculture and closed-loop recycling of resources.

Ford reckons it can cut water used in vehicle manufacturing by 72% by 2020 without damaging the bottom line, by adopting water-saving technologies in tasks like vehicle painting. H&M claimed (pdf) recently to have cut carbon emissions from operating its 4,300 stores by 47% in just 12 months. Apple now claims to get 96% of its energy from renewable sources.

Replicating Apple’s achievement would make Walmart’s gigatonne target very doable since, according to Elizabeth Sturcken from the Environmental Defense Fund in the US, electricity is the biggest activity that contributes to emissions in the US retail supply chain.

Can H&M be “climate positive” by 2040 as it promises? Yes. With energy saving, renewable energy and some offsetting with forest protection, it could deliver negative emissions.

Too much facile PR

For companies to meet their pledges two key things need to happen. First, they must genuinely believe that they need to change their business model in order to succeed in future, by prioritising recycling and reduced resource use as well as the bottom line.

And second, noisy activists must hold directors’ feet to the fire when they falter, so concerned consumers and shareholders can make informed choices.

There is still too much facile PR and wishful thinking in boardrooms and press offices. One example from my in-tray: Swedish textile and furnishing brands, including suppliers to H&M and Ikea, boasted in March that they had “saved almost 7bn litres of water … enough for the daily needs of 134 million people.”

Sorry to be picky, but that is nonsense. The water saving was made over four years; you can’t compare that with daily needs. The saving was equivalent to the basic water needs of just 92,000 people over that time.

And Nestlé says it is “committed to being responsible stewards of water”, but has continued to pump water for bottling from beneath the California desert during the region’s worst drought for centuries.

Even the largest companies will have problems meeting big promises that depend on their suppliers. Unilever is beholden to palm oil supplier Wilmar, whose promise to end deforestation in its supply chain by 2015 has been widely dismissed as unfulfilled. But their market position gives them a responsibility to drive up industry standards.

And, in the end, the more brands that buy into a green image the better. Not least because defending the brand is a core activity for any corporation. Once they have started on this journey, it may be hard for them to deviate too far.

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