You raise an important point around depreciation, though I don't follow your figuring.
Batteries are getting cheaper by 18% a year. A sound deprecation schedule needs to include this innovation component to prevent a yawning gap developing between asset values and replacement costs.
Similarly with wind farms. The new big turbines are way more efficient and the older kit needs to be written down to properly reflect its current worth.
This is the cost of operating in an energy revolution. Ignore it at your peril.
Ash .
IFN Price at posting:
80.3¢ Sentiment: Buy Disclosure: Held