Why is my laptop losing power plugged in?

Whenever I start my laptop, if I don't close it at the Windows 8 boot logo, it would shut off. The charger light would show green but turn orange quickly then shut off. Sometimes when I get it to boot, I can't do much because it would shut down fast. I keep it in the charger whenever it is booted but it loses charge instead of gaining charge. I tried to take the battery out (while it was on) but it instantly shut down. Can anyone help me?