Prior to an investment, it is wise to draw up a business case. In a business case, in addition to investment, any tax regulations, investment contributions, and certainly also the annual costs for maintenance are included.
Always review and assess the business case over a long period of time. If we compare the yields of 1 medium-sized wind turbine with 2 or 3 small wind turbines, we see that the yields per year, and certainly also in the long term after deduction of the investment, are greater.
The WES wind turbines (former Lagerwey wind turbine) have proven themselves since the 1980s, and have a lifespan from at least 25 years. Be sure to include this experience in lifespan in your considerations.