The voltage delivering 1 watt depends on how many amps are present. We use watts to measure power (P), and amps (I) times volts (E) equals watts.
The urea and water that make up urine are removed from the blood in  the kidney. This is then passed on to the bladder which will be  excreted as urine.
This excess urea is then taken out of the body through the kidneys as a component of urine. Some bacteria have the ability to produce an enzyme urease as part of its metabolism to break down urea to ammonia and carbon dioxide.