There are few openly available quantitative results about IOTA. Motivated by this fact, we experimented with IOTA on two different IoT devices and two modern desktop and server computers. We found that despite the theoretical scalability of the Tangle, the actual IOTA protocol has relatively high energy consumption. The Proof-of-Work and transaction signing operations are computationally complex relative to the limited capabilities of many IoT devices and and may be impractical on energy-limited / battery-powered devices.
Note: this article uses results from the research paper Distributed Ledger Technology and the Internet of Things: A Feasibility Study, presented in the 1st Workshop on Blockchain-enabled Networked Sensor Systems (BlockSys).