Two-Way Satellite Time and Frequency Transfer (TWSTFT) has been used as a trusted time transfer and synchronization for a long time, and this approach typically provides timing accuracy of 100 ns or better. However, TWSTFT comes with high implementation costs and a complicated setup, from precisely pointing the dish to align with a satellite in geostationary orbit, to configuring many different devices to interoperate for time transfer to function. At the US Department of Energy’s (DOE’s) Center for Alternative Synchronization and Timing (CAST), we are identifying and assessing alternative timing and synchronization technologies, and among our goals is to lower cost and ease integration for industry, to hasten adoption and improve resilience. This paper highlights research into TWSTFT operational performance and efficiency compared against terrestrial links between mirrored grandmaster and slave clocks more than 1000 miles apart. We evaluate the performance of precision time protocol (PTP)-based clock synchronization using DOE’s Energy Sciences Network (ESNet), compared with TWSTFT, for wide area synchronization between clock implementations at Oak Ridge National Laboratory (ORNL) and Idaho National Laboratory (INL). Outcomes of this research will highlight the performance, accuracy, cost, and efficiency trade-offs between terrestrial and space-based approaches for time transfer to inform capital and architectural investment decisions at energy utilities.