To control power we can use the solid-state relays or so called SSRs. These components already have the TRIAC and the firing circuit inside, we can easily control this with a 5V pulse from the Arduino. 3000W divided by 240V is around 13 amps of current. That’s why I bought some high-power relays, one is of 25 ampers. We could add a heat dissipator on top just to make sure I won’t burn them put or have any other problems. Finally, together with the Arduino we need a screen to show the temperature, power and setpoint values and some extra components such as some push buttons, maybe a buzzer and an LED or even a rotary encoder for adjusting the values. Have thick wires as well for the power connections. To supply the Arduino, we need 5V and I’ll get that with a cheap and simple switch mode power supply, in this way both the heater and the low voltage parts could be supplied with 240V from the main outlet. The rest of the components could be some wood for support, maybe screws and nuts, maybe some glue and so on. See full list below. So, let’s start.