And if you look at Lazard's most recent report -- The Levelized Cost of Energy Storage -- you'll see the graph below, which shows how various different battery projects earn revenue and generate IRRs.
Some are attractive, and others not so much.
Moreover, most battery revenue streams are not contracted for long periods of time, as you might have experienced with 20-year solar PPAs. Ah, the good ole' days...
And if you're eager for more details, then grab a beer or coffee and settle into its 60 glorious pages of battery fundamentals.