Seoul city solar panels are far from meeting the expectation.

Seoul city solar panels are far from meeting the expectation.
I am interested in renewable energy especially after the fine dust problem and faced the following news today. Need “100 years” to pay the installation cost of Solar panel in
Seodaemun Museum (in Seoul)” and the museum will remove the rooftop solar power plant on October 23 since it cost 588m won to install it (the year 2009) but saves only 4m won per year.
The reflection of the light would be best if it is headed to “South”, but due to complaints from the neighborhood, it is headed to West, which resulted in poor efficiency. Sadly, other rooftop solar panels are not running well either.