  The high energy consumption of proof of work-based distributed ledgers has
become an important environmental concern. Bitcoin, for example, consumes as
much energy in a year as a developed country. Alternative consensus mechanisms,
such as proof of stake, have been shown to use drastically less energy than
proof of work-based DLTs. For example, the IOTA DLT, built upon a directed
acyclic graph (DAG) architecture, uses an alternative consensus mechanism that
requires significantly less energy than other DLTs. Because the (DLT) space is
constantly and rapidly evolving, the question of how much energy DLTs actually
consume demands to be continuously studied and answered. Previous research into
the energy consumption of the IOTA network has shown that an optimization in
the overall protocol correlates to an optimization in energy consumption. The
planned IOTA 2.0 update, built upon the GoShimmer research prototype, promises
to further optimize the protocol by removing the network's centralized
Coordinator. This report presents the results of measuring the energy
consumption of a private GoShimmer network while comparing these findings to
previous research into the current mainnet, which is called Chrysalis. The main
findings of this report are that the IOTA 2.0 research prototype shows both
improvements and increase in the energy consumption metrics compared to the
Chrysalis network. Additionally, this report defines a model to estimate the
total annual energy consumption of an IOTA network. This model should be
significant for future research as it enables a way to estimate the total cost
of running the IOTA network as well as its carbon emissions. Moreover, having
an annual power consumption metric allows for better objective comparisons to
different DLTs.
