Based on much of what I have read over the past several years, the ability to effectively store energy / renewable energy is one of the keys to the future dominance of non-fossil-fuel-based energy sources.
With that thought in mind, I came across this well researched paper and thought others might find it helpful. It does a great job of showing how various business models for the application of the leading forms of energy storage compare in terms of profitability. I was surprised by how few studies the authors were able to find on the subject (no fault of theirs as this seems to be a well-researched study), but they do a great job of listing all their sources at the end of the paper.
Please note that this is dated July 2019, so it is possible that many EC members may have already read this.