I'm new here and I need some help regarding my project. I am aiming for building our house an emergency lighting system. I like electronic stuff, I do all electrical repairs and mod to our house, it's my hobby. But I didn't take electronics so I am a bit lacking with basic knowledge. I am planning of doing this by buying bright LEDs wire them in parallel so when the time comes, typhoon or something and the light goes out, we can have a bright well lit house, seeing our stuff will be enough although no electric fans and all, we just can't keep on buying candles which are very dangerous and cause fires. Things I am aiming for: LED's wired in parallel circuit On and off switch detachable battery plug (so we can remove and replace batteries) a 30,000mah portable power bank as a power source or bigger Rechargeable (30,000mah power bank used to charge my smartphone or I can buy bigger capacity batteries from our electronic store) Basic circuitry and system Here's where I need help, i don't know what LED I need to buy, I just want the small once that lasts long though depending on the battery capacity. I don't know their specs, I dont know which is best for this project, Our main area where I need to set this thing up is our sala. Our sala isn't very big, probably just 5 meters square I will hook the LEDs in a parallel circuit, stick them to the ceiling spanning all four sides of our sala. if I use the 30,000 mah power bank for cellphones as their power supply, how long will it lasts? what type of LED will be bright enough and consume low power for them to light for long hours? Does buying bigger battery means easy replacement? will it lasts longer? If I buy the large battery from the store, I need to recharge it, how can I build a charger, I saw they were just selling battery I don't know how I can recharge the things. Thanks guys!