Historically, energy constraints have limited the spatial range, endurance and capabilities of ocean observation systems. Recently developed wave energy conversion technologies have the potential to help overcome these limitations by providing co-located and persistent power generation for ocean observations, enabling new opportunities for ocean research. In this paper, we develop the first techno-economic model for wave-powered ocean observation systems and use the model to study system characteristics and cost drivers. Our model utilizes time-domain simulation and optimization to identify cost-optimal system characteristics and to estimate capital and operational costs. Using our model, we evaluate the use of wave energy to power a 200 W ocean observation system deployed for five years at five unique geographic locations. We found that, depending on the geographic location, cost-optimal wave energy powered systems require an ≈ 0.5–3 kW wave energy converter and an ≈ 15-50 kWh battery. The corresponding range of power system costs over the deployment duration is between $110,800 and $673,200. We build on these results by performing a sensitivity analysis of key model parameters and identifying the potential economic impact of future technology advancements. Overall, our results indicate that characteristics of the geographic location, power system durability, and electrical power demand are key drivers of power system economics for ocean observing.