This paper presents the design considerations and implementation of Heliomote, a solar energy harvesting module for wireless embedded systems. The authors highlight the challenges of designing solar energy harvesting systems, including the need to match solar panel and battery characteristics, manage energy storage, and optimize power consumption. They also discuss the trade-offs between different energy storage technologies, such as batteries and ultracapacitors, and the importance of understanding battery non-idealities like self-discharge and round trip efficiency. The paper also describes the design of the Heliomote module, which includes a solar panel, battery, and power management circuitry, and presents its performance evaluation. The results show that Heliomote enables near-perpetual operation of sensor nodes by autonomously managing energy harvesting and storage. The paper also discusses the importance of harvesting-aware power management, which can improve system lifetime compared to battery-aware approaches. The authors conclude that environmental energy harvesting is a promising technique for extending the lifetime of wireless embedded systems, and that careful design considerations are essential to maximize the efficiency of solar energy harvesting modules.This paper presents the design considerations and implementation of Heliomote, a solar energy harvesting module for wireless embedded systems. The authors highlight the challenges of designing solar energy harvesting systems, including the need to match solar panel and battery characteristics, manage energy storage, and optimize power consumption. They also discuss the trade-offs between different energy storage technologies, such as batteries and ultracapacitors, and the importance of understanding battery non-idealities like self-discharge and round trip efficiency. The paper also describes the design of the Heliomote module, which includes a solar panel, battery, and power management circuitry, and presents its performance evaluation. The results show that Heliomote enables near-perpetual operation of sensor nodes by autonomously managing energy harvesting and storage. The paper also discusses the importance of harvesting-aware power management, which can improve system lifetime compared to battery-aware approaches. The authors conclude that environmental energy harvesting is a promising technique for extending the lifetime of wireless embedded systems, and that careful design considerations are essential to maximize the efficiency of solar energy harvesting modules.