Grumpy_Mike:
You can't say that, you need the voltage and current in values that your component needs them. You can only talk in power terms if you are producing the current and voltage you need using a switching regulator and I don't think you are.Your regulator uses a 2n3055 transistor as a linear regulator so the current drawn from the power supply is going to be the same irrespective of the voltage you regulate it to.
So 1A at 5V regulated by a linear regulator is going to be 1A at 19V from your power supply. So it takes 19W from your power supply to provide 5W of useful power in your load. The difference in power 19 - 5 = 14V @ 1A = 14W is burned off by the regulating transistor. Which is why it gets hot, and it could be that an infinite heat sink is not sufficient to burn off this power. It is all to do with the thermal resistance between chip and case and case and ambient. You have no control over the chip to case thermal resistance, you find that in the data sheet.
For more information see:- http://www.thebox.myzen.co.uk/Tutorial/Power.html and the examples page found off that.
aha, thank you for your information. I see this project has failed due to lack of knowlegde. I'll retry this project when I've got new components(the heatsink issue has been fixed).
And I've got a new project.