How does the keurig/coffee maker make that amount of cold water so boiling hot in such a quick time?
In: Engineering
One thing to consider: there is no device that can heat water disproportionately faster than any other device using just electricity. A typical small appliance like this is going to max out at about 1500 watts.
1500 watts for a minute (1500 watt-minutes) is about 90,000 joules.
To heat a gram of water from ~20 C to boiling (100 C) at standard conditions takes about 330 joules. There’s about 225 grams in a serving, so we need ~75,000 joules (225 * 330).
This means the theoretical maximum speed for a 1500 watt small appliance to bring an 8 ounce cup of water from room temperature to boiling is 50 seconds.
But it doesn’t have to bring the entire volume to boiling first. It can heat a small portion of water up and pass that through the cup while continuing to heat more water. That way the cycle is completely done by the 50 seconds. Further, I don’t think Keurig actually goes up to boiling (not sure).
Latest Answers