VoxEU, September 27, 2023. HTML.

From the conclusions:

… it is critical to account for indirect in addition to direct social costs and benefits when ranking monetary architectures.

… the costs and benefits we consider point to an important role of central bank digital currency in an optimal monetary architecture unless pass-through funding is necessary to stabilise capital investment and very costly.

… the interest rate on CBDC should differ from zero and from the rate on reserves.

From the text:

Notes: The dark grey area represents the efficiency advantage of CBDC needed to make it less costly than a two-tier system with optimum reserve holdings. The light grey area displays the same object but based on actual US reserve holdings rather than model-implied optimal ones. These distributions allow for pass-through costs and tax distortions, quantified by assuming taxing households causes deadweight burdens of 25% per tax dollar. The distributions are based on two million realisations.