DIY DC Electric Power

Electric power is a broad topic that I am going to break up into more specific topics.

I am going to focus on topics typically learned by DIY hobbyists.

DIY Power Subtopics:

  • Power source
  • Component/circuit wattage (load/work done).
  • Storage (battery)
  • Conversion (buck/boost/inverter).
  • Generation (Solar/rotation with wire and magnets).

Power Source Topics:

  • Bench power supply.
    • Adjustable constant voltage. Provides the needed current to maintain the set voltage.
    • Adjustable constant current. Adjusts voltage up or down as needed to maintain a certain amount of current.
  • Other AC to DC power supplies.
    • AC to DC adapter (wall wart).
  • Battery: Portable and low priced for low power applications.
  • Connectors.
    • USB.
    • Barrel plug.
    • Screw terminal.
    • Breadboard.
    • Jumper wire/cable.


Electric power is ultimately converted into something useful, and waste heat.

  • Heat
  • Light
  • Motion
  • Modules (prebuild circuits with various input and output connectors).

Energy Storage:

Energy is often stored for later use. The electric grid uses mostly non battery means to store energy, but the rest of us use batteries almost all of the time.

  • Battery:
    • Chemistry (cell)
      • Lead acid
      • Lithium ion
      • LifePo4
    • Series: Higher voltage from a battery pack/bank.
    • Parallel: More capacity (current over time) from a battery pack/bank.
    • Capacity (amp hour)

Power Conversion:

It is common to have a certain voltage available to you, but not the voltage you want to use.

  • Buck converter: Some of the voltage coming in is converted into current coming out. Reduces waste heat of a load.
  • Boost converter: Some of the current coming in as turned into more voltage coming out. Lets a power source power something that needs a higher voltage.
  • Inverter: Lower voltage (usually) DC power source current is turned into more voltage, which is also alternated (AC) into a sine wave. Usually to the voltage of the household and business electrical outlets in the area. Approx. 120 volts AC at 60 hertz in the United States.

Other topics:

  • P = VI = I²R = V²/R