A boiling kettle is essentially a large metal vessel for boiling up your wort to extract the oils from your hops which provide the bitterness and aroma to your brew. In that sense it’s a very simple device, simply a large stainless steel pot with a tap in the bottom of it and some sort of heat source capable of bringing 30-50L of liquid to a rolling boil.
There are two common approaches – electric and gas.
Electric is certainly the clean and simple approach. You either mount some heating elements directly into the bottom of your pot, or even easier you get an immersion element that simply dangles in it when you need it.
The problem with electric is that elements generally only run at 2400W. I say “only” because although this is a large amount of power, it really is pretty underpowered when you consider how much work it’s going to need to do. To raise 35L of water from 20C to 100C is going to take about 100 minutes! And that’s in an ‘ideal’ vessel where there’s no heat losses to the outside world. To make this approach work you’re going to need to insulate the bejesus out of the pot and even then it’s going to be slow and rack up the power bill.
You can run two elements to deal with the lack of power, but the initial cost doubles and you run into the problem where you’re now trying to pull more power than one household circuit is rated to supply. Which means that the solution is a long extension cord to another circuit elsewhere in the house.
Option two is gas. The amount of heat output from gas is immensely higher – so boil times are drastically reduced. This is the option I have gone with and my 23 jet mongolian burner turned up in the post today!
Now I just need to collect a hose with bayonet fitting, a natural gas regulator, a valve and some suitable gal pipe.
Spend for my burner: $75.
Retail burner: $115.
Spend so far: $130.
Savings so far: $1340.