The concept is to light up the dark narrow streets with prism and solar lamps. This is ecological street lighting, which will work both during the day (prism) and after dark (solar lamp), improving the quality of life and safety of the city's inhabitants. Lighting the dark, narrow streets of Asian cities, especially in poor and dangerous areas, is a huge problem. The cost of 1 kWh is about 1.1142 HK $. Assuming that electric lamps would have to illuminate such narrow streets about 15-16 hours a day, depending on what width the street has, we can calculate that the daily charge for one streetlamp is: 0.22kWh x 1.11 HK $ x 16 = 3.902 HK $ and annually it is: 3.902 HK $ x 365 = 1426.13 HK $ We have to remember, that poor planning and design flaws are causing safety issues in the narrow back streets of large Asian cities. Usually, these streets are always in the shadow even during the day. People need light for both physical and mental health. According to WHO nearly 800,000 people die by suicide worldwide each year, which is roughly one death every 40 seconds. Exposure to sunlight accounts for over 90% of the vitamin D requirement for most individuals. Vitamin D has been reported in the scientific and lay press as an important factor that may have significant health benefits in the prevention and the treatment of many chronic illnesses, such as depression.