Explore power management strategies for low and ultra-low power systems in this 22-minute Hackaday talk. Learn to select appropriate power sources, optimize power usage, and validate power consumption early in the design process. Discover techniques for estimating energy from various sources, including solar panels and kinetic systems. Gain insights into critical design decisions, back-of-the-envelope calculations, and prototype validation methods. Understand the importance of power planning and its impact on system design and product success. Delve into topics such as wave energy, thermoelectric power, solar energy, Maximum Power Point Tracking (MPPT), common pitfalls, design goals, power budgeting, shipment conditions, power visualization, low current measurement, firmware testing, and power testing for various use cases.