Smart Energy Acquisition and Management System(SEAMS)

Affordable off-grid solar installations in developing communities lack the automated intelligence needed to maximise energy capture, protect battery health, prioritise critical loads during scarcity, and give users real-time visibility into their system resulting in power loss to essential services, premature battery failure, and wasted solar irradiance.Fixed panel mounting loses 20–40% of available energy daily as the sun moves across the sky. When batteries run low, all loads cut simultaneously regardless of priority a classroom lamp, a phone charger, and a community water pump treated as equals until everything goes dark at once. Users have no visibility into generation, consumption, or battery state, leaving faults undetected and usage decisions uninformed. Without charge control, lithium packs overcharge and degrade prematurely, making the long-term economics of solar adoption far worse than they should be. SEAMS addresses all four gaps in one integrated, ESP32-based system: Dual-LDR sun tracking continuously orients the panel toward maximum irradiance, recovering up to 35% more daily energy yield versus fixed mounting Dual INA219 sensors measure solar input and load consumption precisely in real time Relay-based charge control automatically disconnects and reconnects solar to protect battery longevity 3-tier load shedding preserves critical services longest as battery voltage declines Local IoT dashboard via Node-RED 16×2 LCD provides on-device monitoring

Smart Energy Acquisition and Management System(SEAMS) Overview This is a fully integrated, ESP32-based off-grid solar energy management platform that addresses four critical problems in a single coordinated architecture: inefficient solar capture, lack of intelligent load management, absence of real-time monitoring, and uncontrolled battery charging. Every subsystem reinforces the others the tracker maximises input, INA219 sensors measure flows, the charge controller protects the battery, the load-shedding engine prioritises critical services, and the Node-RED IoT layer surfaces it all on a local Wi-Fi dashboard. System Architecture The ESP32 dual-core 240 MHz microcontroller was chosen for its native Wi-Fi (enabling an offline hotspot), sufficient GPIOs for all peripherals, and 12-bit ADC precision. A forward-compatible upgrade path to Raspberry Pi 4 enables persistent logging without firmware changes. Solar Sunflower Tracker Two LDRs mounted symmetrically with a shadow divider feed a differential signal to an SG90 servo. A ±120 ADC dead zone prevents oscillation, and EMA smoothing (factor 0.85) filters noise. A two-loop design 500 ms sensing, 30 ms 1° servo increments — produces smooth, sunflower-like tracking, increasing daily energy harvest by up to 35%. Precision Energy Monitoring Two INA219 sensors (I²C addresses 0x40 solar, 0x41 load) measure voltage, current, and power bidirectionally. Battery SoC is linearly interpolated between 9.0 V (0%) and 12.6 V (100%) for a 3S Li-ion pack. A separate ADC channel on GPIO 33 produces an EMA-smoothed solar irradiance percentage. Relay-Based Charge Control A relay on GPIO 27 disconnects the solar panel at 12.6 V and reconnects it at 11.1 V. The 1.5 V hysteresis gap prevents rapid cycling and significantly extends battery service life by avoiding overcharge and deep discharge. Three-Tier Load Shedding The `manageTiers()` function reads battery voltage and switches three GPIO-controlled load tiers: Tier 1 (Critical, GPIO 23):ON until 9.0 V,Tier 2 (Medium, GPIO 12):OFF below 10.8 V,Tier 3 (Low, GPIO 15):OFF below 11.4 V This mirrors grid-scale load shedding at household scale, keeping critical loads alive far longer than unmanaged systems. IoT Monitoring The ESP32 publishes nine MQTT topics every 5 seconds to a broker (laptop in prototype, Raspberry Pi 4 in production). A Node-RED dashboard accessible offline via the ESP32's own Wi-Fi hotspot renders live gauges, charts, and status cards on any smartphone. A 16×2 LCD cycles through five on-device status screens for users without mobile devices. Future upgrades include RTC scheduling, GSM SMS alerts, and a web-based configuration portal. Expected solutions SEAMS increases energy generation, extends battery life, ensures critical loads remain powered, provides real-time system monitoring, and operates without internet connectivity, creating an intelligent and reliable solar energy solution for homes, schools, and clinics.