Calculate how much power is needed daily and best power source to use?

Using Arduino Project Guidance
1

Hello everyone :slight_smile:

I am new to the Arduino world so I hope I don't sound super confusing or stupid.
I am trying to build a trash bin fill sensor using ultrasonic sound. You can Google about this project and you'll find MANY articles on it.

Basically, I am going to put an Arduino/Sensor on the bottom of the lid that's on the inside of the trash can.
As trash is thrown into it, the sensor will pick up that the distance to the bottom of the trash can is getting shorter. As the distance approaches 0, there will be an LED to indicate that the trash can is full.

Here are all the parts I am going to use, I need to know how to determine how much power it consumes daily and what the best source of power for it.

• UNO R3 Board
• SR04 Ultrasonic Sensor
• 1 (maybe 2) LED - The kinds that usually come with a starter kit, 5mm LED.

What would be a good power source for this project that would last at least a month?

2

Put together your design on a hard-wired power supply. Measure the amp draw of your working circuit using an amp meter. If you want to consider battery power, you will need a battery that can supply x volts at y AmpHours. If you get a sensor like the one from Adafruit, and run everything at 3.3 volts, adding a 3.3 volt LDO or DC-DC converter, you can run off a lithium-polymer battery, the most dense battery to date. If at 3.3 volts your circuit draws 100mA, to run for a month, you would need about 75 AmpHours. It's probably much more compact to stick a power supply on the lid and run a cord behind the can to an outlet.

3

Sounds like you need to arrange a switch so that it is only powered while the lid is open and for a few seconds afterwards.