This week is the 45th anniversary of Earth Day, and its celebration is accompanied by the hopes of tens of millions of people that this is the moment when sustainability and economic growth find a real balance. According to the experts, to be successful, everyone– including brands must commit to a low carbon future.

For brands, simply playing in the environmental awareness arena as part of a CSR public relations campaign isn’’t really an option anymore. Brands must do it in ways that meaningfully support a sustainable future palpable to the consumer.

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And as the number of companies trying to co-opt the environmental movement for their brands has grown, so too have the number of skeptical consumers. Most consumers have heard such promises before and,– in the face of increased expectations,– have begun to demand authenticity. They understand that the technology exists, and more and more consumers feel that all brands need is the will to make it so.

To borrow a phrase from the Wizard of Oz, consumers want brands to be “morally, ethically, spiritually, physically, positively, absolutely, undeniably, and reliably” green. And of the 550 brands indexed1, these are the top 50 brands deemed authentically “green” by their customers. They are presented alphabetically since environmental demands and consumer expectations are category specific.

  1. Acer
  2. Adidas
  3. Air Canada
  5. Apple
  6. AT&T
  7. Aveda
  8. Avis
  9. Brother
  10. Budget
  11. Burt’s Bees
  12. Canon
  13. Chic-fil-A
  14. Chipotle
  15. Coke
  16. Dell
  17. Discover Card
  18. Dunkin’
  19. Epson
  20. Ford
  21. Hilton Hotels
  22. Home Depot
  23. Honda
  24. HP
  25. Hyundai
  26. IBM
  27. InterContinental Hotels
  28. JetBlue
  29. Kohl’s
  30. Konica-Minolta
  31. Le Pain Quotidian
  32. Macy’s
  33. McDonald’s
  34. New Balance
  35. Nike
  36. Panera
  37. Peet’s
  38. Pepsi
  39. REI
  40. Samsung
  41. Starbucks
  42. Subway
  43. Tom’s of Maine
  44. Toyota
  45. Under Armour
  46. United
  47. Walmart
  48. Whole Foods
  49. Wyndham Hotels
  50. Zappos

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2015 could be the year in which world leaders finally pass a binding climate change treaty, prompting citizens and corporations to divest from fossil fuels and put their sustainability and renewable energy solutions where their wallets are. It turns out that consumers are fiercely loyal to brands that do that.

If you want to put your own ethical and environmental standards to the test, Earth Day Network has a Personal Footprint Calculator, so you can see the impact you’re having on our planet.

When it comes down to the bottom bottom-line, unlike brand loyalty, it’’s just like what environmentalist Wendell Berry said, “”The earth is what we all have in common.””

Included in the Brand Keys 2015 Customer Loyalty Engagement Index (CLEI)
Images: Andreas Klinke Johannsen // Flickr