Convert GreenCoins to Carbon Coins!

6 October 2020

GreenCoin redemption capability is now further extended! You can exchange your GreenCoins for Carbon Coins* at any reverse vending machines (RVM) on campus, thus broadening the usability of rewards on both schemes!

Click here to view how it works

With this new arrangement, you can exchange at a rate of 1 GreenCoin to 1 Carbon Coin. With enough GreenCoins with your GreenCoin app, you will be able to see the corresponding in-app e-coupons and you can select if you want to convert 20, 30, 50 or 100 Coins. Simply redeem that e-coupon to put it “In Your Pocket”, and then visit the RVM to do this conversion – enter your Carbon Coin Membership ID (if you are already a registered Carbon Coin member, it means your mobile number) and let the machine scan your in-app e-coupon – and it’s done!

Earn GreenCoins and convert them just the way you like!

Also read the E-COUPONS section for details.




*Remarks: Carbon Coins is a local incentive-based scheme operated by the Carbon World Limited with its dedicated mobile app. Carbon Coins offers its registered users who support recycling with different types of rewards such as product coupons and Octopus Card cash rebate. Please approach Carbon World Limited if you have any question related to this Carbon Coin scheme, its rewards and content, its mobile app, and its scope of service.



Terms and Conditions apply.

  • This is open only to current PolyU staff and students who are valid GreenCoin users.
  • Check your GreenCoin balance before you redeem any in-app e-coupon. Your GreenCoins are maintained your GreenCoin app and will be deducted when you decide to convert GreenCoins to e-coupons/awards.
  • This coin conversion activity between PolyU GreenCoin and Carbon Coin does not require the transfer of your data including your NetID, your email, and your name between the two schemes.
  • A quota applies.
  • This conversion can only be processed by making use of the scanning function at the reverse vending machines in operation on campus.
  • You can exchange at a rate of 1 GreenCoin to 1 Carbon Coin.
  • You should also be a valid Carbon Coin member in order to complete this conversion and be able to consume the Carbon Coins. You will be required to validate your Carbon Coin membership account by inputting your mobile phone number at the reverse vending machines before scanning, which shall be your voluntary action.
  • Once the conversion is completed, it is irreversible and it cannot be cancelled, returned, exchanged or traded for cash or other promotion.
  • The corresponding Carbon Coins will be credited directly to the valid Carbon Coin user’s membership account within 24 hours from the time of successful scanning. No separate notification will be issued. Please check your Carbon Coin balance and activity with your Carbon Coin mobile app.
  • PolyU shall not be responsible for any failure to process any conversion arising from the users’ exit, voluntarily or involuntarily, during any of the steps of e-coupon scanning/conversion, including but not limited to network disconnection and technical device malfunction.
  • Unless otherwise specified, the GreenCoin Terms and Conditions apply.
  • Carbon Coins and its related mobile app, membership data, reward scheme details and content are the properties of Carbon World Limited solely. PolyU accepts no responsibility for their contents, development, operation and maintenance, and accepts no liability for any loss or damage arising from any use of Carbon Coins. Please approach Carbon World Limited if there is any question.
  • PolyU and Carbon World Limited reserve the right to amend and change the details of this conversion scheme or suspend this scheme without prior notice. In the event of dispute, the decision of PolyU and Carbon World Limited shall be final.

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