Power Consumption on Arduino?

Question

I curse the internet for being this stupid!! Not one single good result or accurate one!
Can someone please just tell me how much power does an Arduino Uno consume on a 5V regulated battery? Though I'm not using it on its own.
The Arduino Uno is connected to ITEAD GPS Shield (or Arduino GPS Shield). I checked for datasheet, but there was no precise power consumption for it. Just how much voltage you can give it.

To be more precise, I'm using 4 pins from the Arduino Uno. Rx, Tx, 5V and GND, and all these pins are going to the Arduino GPS Shield. The code is simple: Just get Latitude and Longitude and send it to Arduino Ethernet Shield. THAT'S IT! No SD cards, no other functions... Nothing. I don't care how much power Arduino Ethernet Shield needs as long as I know its functioning. I just want to know how much power is being consumed with this setup, on a 5V regulated voltage source. Again: Arduino Uno +Arduino GPS Shield. Pins used: Rx, Tx, 5V and GND.

Oh and if you happen to find the Arduino GPS Shield datasheet, try to shut that site down because half the information in there is WRONG! How do I know? A LOT of testing.

Answer 1

37 mA at 5 volts for the Uno alone, and a whopping 210 mA with the Ethernet shield.

Answer 2

Get an ammeter. The power consumption can vary depending on conditions. In fact, if you did a LOT of testing to find that the information in the datasheet is wrong, you must already have one (of course you might be using it wrong).

Answer 3

Connect a DC current meter to measure it, current rate is not fixed while it is running !