Present and future automotive electrical loads are surveyed relative to power and electrochemical storage requirements. It is concluded that existing power and energy needs are near the maximum capability of the existing 14-V system, and that future automotive loads may be 10 kW or more. The efficiency of the electrical distribution system at this power level requires a higher voltage and safety considerations dictate that a 42-V limit will be the most satisfactory standard. The higher-voltage systems will likely include advanced controls, thermal management, and more complex architectures.