Nowadays so many areas are highly polluted. Big cities are covered in smog. Some people have aircos but the quality of the air is often still very bad. Why can’t we all have a Green Lung in our homes? If you have enough plants in your home you may not need the polluted air from the city. Some questions: 1.) How many plants are needed to supply oxygen for one person? 2.) Which type of plants? 3.) How to store and take care of so many plants in one city apartment? I found these links: link 1, link 2, link 3. I’m already dreaming and will make and publish a first prototype here soon. If you like to help, please email to: firstname.lastname@example.org and/or check this site once in a while to see the progress.