The voltage in India is usually 220V and the power outlets comply with European standards, but it is not always the case: lots of hotels use Indian standard (with 3 large round plugs).  Investing in a power adapter won’t be costly and will always be useful for your travels. Power cuts are common; they are often quite short but can last for a longer time. Furthermore, in India, each power outlet has a switch. If the outlet isn’t working, make sure that it is indeed switched on!