After a wind turbine expires, it stops producing power. An expired turbine is distinct for its weak opacity. You need $1 more to replace it. If the reactor is full of wind turbines, it may be hard to replace them one by one. You need to buy Wind turbine manager, under the Research tab, to make this automatic. In the upgrade tab you can buy lifetime upgrades.
Wind turbine lifetime and efficiency may be upgraded in the Upgrade tab.
|Price||Lifetime Upgrade||Price||Efficiency Upgrade|
Strangely, when you try to place a wind turbine on a loaded heat cell, the game says, "You can only build max 1 heat producing cell(s) on this reactor."