The Smart Energy Home
PV, battery storage, heat pump, EV charger — a modern home has many energy sources and consumers. Without smart management, maximizing savings is difficult. HEMS (Home Energy Management System) is the brain of a smart energy home.
What is HEMS?
HEMS automatically manages energy flows: monitors PV production, routes surplus to storage or consumers, controls heat pump timing, schedules EV charging, and optimizes for tariff rates.
Smart Home Architecture
| Component | Function | Protocol |
|---|---|---|
| PV Inverter | Energy production | Modbus TCP / SunSpec |
| Battery Storage | Energy buffer | CAN / Modbus |
| Heat Pump | Heating/cooling | SG Ready / Modbus |
| EV Charger | Car charging | OCPP / Modbus |
| Smart plugs | Appliance control | Zigbee / WiFi |
| Weather station | Production forecast | WiFi / API |
| HEMS controller | Overall management | Ethernet / WiFi |
Automation Scenarios
Sunny day: PV produces 8 kW → home uses 1.5 kW → HEMS activates heat pump (3 kW) → surplus charges battery → overflow runs dishwasher → last surplus feeds grid.
Cloudy day with EV: PV produces 2 kW → HEMS delays EV charging to nighttime cheap tariff → battery powers evening use.
How Much Does HEMS Save?
| Configuration | Without HEMS | With HEMS | Extra savings |
|---|---|---|---|
| 8 kWp PV | 65% self-consumption | 78% | +€420/year |
| PV + 10 kWh storage | 80% | 92% | +€280/year |
| PV + storage + heat pump | 75% | 90% | +€580/year |
| Full system with EV | 70% | 88% | +€740/year |
Popular HEMS Systems
SolarEdge HOME, Fronius Wattpilot, Huawei FusionSolar, Home Assistant (open-source), E3/DC.
Implementation Costs
HEMS costs €700 – €2,300 depending on complexity. With annual savings of €420 – €740, ROI is 1-3 years.
FNC Poland installs and configures HEMS as part of comprehensive renewable energy installations.
