Could you tell me more about the acurate power consumption measuring? I don't get it. I mean what is the difference? My variable power supply has 20A max outpu, when it senses that the load has too small resistance, it decreases the voltage to keep the amps at constant max setting. This is how I got the 13.5V 20A. I mean watts are watts Am I missing something here?

Also, how can I dose the electrolyte concentration? I have the KOH in a form of white flakes. Do I weight these flakes?
Should I sand blast the plates to increase the surface area?