I am a nightshift worker and had my bedroom windows fitted with the solar powered block out shutters, while they are heaven to my sleeping patterns, the batteries have shit themselves three times in six months. Not what you want to happen when looking forward to a good daytime sleep. The company was great, all covered by warranty but they don't know the cause of the prob so they are replacing them with full electric at no charge. It is a common problem with the solar ones, don't get them

Approximate cost: $4000