I brew beer as a hobby and in order to avoid the cold i want to take my boiling inside. Because propane inside my apartment is dangerous I was looking to heat my boil with a modified electric heating element from a hot water heater. I need to figure out an equation that will tell me how long it will take me to boil a 19 Liter solution that ranges from zero (water for my mash) to 25% (pre-beer) sugar saturation. It is usually around 22 degrees C in my apartment if that helps for the heat disappation factor. I boil with an open pot. For practical purposes i have access to 120V outlets which limits me to a 1500W heating element. I want to find out if 3500W would do the trick and how long it would take to take it from about 70 degrees celcius to a rolling boil, or whether i have to get multiple 1500 W systems and put them all into the pot. Many thanks in advance! I'm an idiot when it comes to physics. Could you help me?