Triodos Bank has investigated the option to provide the IT infrastructure for an economy where companies pay with a currency called United. Uniteds can be bought for Euros, and they can only be used for payment in the United economy. No financial speculation with Uniteds is possible. For example, if a company lends Uniteds to another company, no interest can be paid by the borrower. Uniteds can only be used to pay for something of value in the real economy.

In the investigation, we considered the scenario that the United economy is supported by a blockchain that stores all United transactions. The United economy does not have a costly mining process in which nodes burn energy to provide a proof of work. Rather, nodes in the United economy all share the transaction fees of the economy. This requires all members of the economy to trust the nodes doing the verification. What is the optimal transaction fee structure for the economy? How is this affected by the size of the economy? What is the impact of the fee structure on the number of Nodes who do verification?

Using our tools we provided insight in the structure of the United economy. We showed the effect of raising or lowering transaction fees on the size of the economy and on the number of Nodes.


There is also an interview about this case study with Jaap Gordijn

This interview was produced by Bruno van Wayenburg.


  • “Future Gladiator”, Kevin MacLeod (, Licensed under Creative Commons: By Attribution 3.0
  • Luis Sarro. J.S. Bach, Partita no. 6 in Em, BWV 830 (via

Camera: Lars Berg (

Thanks to Yvette Tuin and Dror Guldin