Integration of buoyancy-based energy storage with utility scale wind energy generation

This paper presents concepts and considerations for integrating a Buoyancy Energy Storage System with a utility scale wind turbine and the Ontario, Canada energy market is used as a case study. Using derived characteristic equations of operation, a Buoyancy energy system is sized for storage of 1 MWh of electrical energy. Practical considerations of float and equipment selection are discussed and hydrodynamic drag losses calculated for the desired float velocity range. Round-trip efficiency is estimated based on calculated losses. Power generation data from a 2.3 MW wind turbine is presented along with the historic energy purchase price data for Ontario in 2015. Total revenue and net revenue resulting from storage is calculated based on historic data and a developed bi-diurnal storage program. Open water testing of a small scale system was conducted in Lake Huron which confirmed steady state operation of the system under sufficient loading