EMHASS Energy Management — Deye + NordPool Setup

Energy Management for Home Assistant (EMHASS) configured for:

• Deye SUN-12K-SG04LP3-EU hybrid inverter
• 32 kWh LiFePO4 battery
• NordPool LV spot prices
• Self-consumption optimization with price arbitrage

---

System Overview

┌─────────────────┐      ┌─────────────────┐      ┌─────────────────┐
│   Deye Inverter │      │  Home Assistant │      │    NordPool     │
│   (MQTT → HA)   │─────▶│    Sensors      │◀─────│   Spot Prices   │
│                 │      │                 │      │   (LV zone)     │
└─────────────────┘      └────────┬────────┘      └─────────────────┘
                                  │
                                  ▼
                         ┌─────────────────┐
                         │     EMHASS      │
                         │   (add-on)      │
                         │                 │
                         │ • Day-ahead     │
                         │   optimization  │
                         │ • Battery       │
                         │   scheduling    │
                         │ • Price         │
                         │   arbitrage     │
                         └────────┬────────┘
                                  │
                                  ▼
                         ┌─────────────────┐
                         │ Forecast Sensors │
                         │ • p_pv_forecast  │
                         │ • p_load_forecast │
                         │ • p_grid_forecast│
                         │ • soc_batt_forecast│
                         └─────────────────┘

---

Daily Workflow

1. NordPool Price Publication (~14:30 EET/EEST)

NordPool publishes next-day spot prices for the LV zone. The sensor.nordpool_kwh_lv_eur_3_10_021 sensor receives:

• today — 96 values (15-min resolution) for current day
• tomorrow — 96 values for next day (once published, typically by 14:30)
• tomorrow_valid — becomes true when prices are available

2. EMHASS Automation (14:30 daily)

trigger: 14:30
  ↓
wait: tomorrow_valid == true (timeout 60min)
  ↓
build: 48-value price list (30-min resolution)
       = NordPool 15-min prices resampled to 30-min steps
       (prices already include distribution + VAT — no offset added)
read: battery_soc_init = sensor.deye_inverter_mqtt_battery_soc / 100
  ↓
POST: /action/dayahead-optim with price list + battery_soc_init
  ↓
wait: 15 seconds
  ↓
POST: /action/publish-data
  ↓
result: Forecast sensors updated with tomorrow's plan

3. What EMHASS Optimizes

With costfun: profit and set_nodischarge_to_grid: true:

• Discharge battery to cover load during expensive hours (sell to yourself)
• Charge battery from grid during cheap hours (price arbitrage)
• Never export to grid (maximum_power_to_grid: 0)
• Maintain SOC between 10%–100%, target 60% end-of-day

---

Configuration Files

EMHASS Config (/addon_configs/5b918bf2_emhass/config.json)

{
  "hass_url": "http://192.168.66.113:8123",
  "long_lived_token": "<HA long-lived access token>",
  
  "costfun": "profit",
  "optimization_time_step": 30,
  "historic_days_to_retrieve": 10,
  
  "sensor_power_photovoltaics": "sensor.deye_inverter_mqtt_dc_total_power",
  "sensor_power_load_no_var_loads": "sensor.deye_inverter_mqtt_total_load_power",
  
  "maximum_power_from_grid": 16090,
  "maximum_power_to_grid": 0,
  
  "load_cost_forecast_method": "list",
  
  "set_use_battery": true,
  "battery_nominal_energy_capacity": 32000,
  "battery_charge_power_max": 11000,
  "battery_discharge_power_max": 11000,
  "battery_charge_efficiency": 0.96,
  "battery_discharge_efficiency": 0.96,
  "battery_minimum_state_of_charge": 0.1,
  "battery_maximum_state_of_charge": 1.0,
  "battery_target_state_of_charge": 0.6,
  
  "number_of_deferrable_loads": 0
}

HA Configuration (/config/configuration.yaml)

rest_command:
  emhass_dayahead_optim:
    url: http://192.168.66.113:5000/action/dayahead-optim
    method: POST
    content_type: application/json
    body: "{{ body }}"
  emhass_publish_data:
    url: http://192.168.66.113:5000/action/publish-data
    method: POST
    content_type: application/json

Automation (/config/automations.yaml)

Located at the end of automations.yaml — see the file for the full Jinja2 template that:

1. Reads sensor.nordpool_kwh_lv_eur_3_10_021 tomorrow attribute
2. Resamples from 96 values (15-min) to 48 values (30-min)
3. Reads real battery SOC and converts to fraction (battery_soc_init)
4. Passes both to EMHASS via load_cost_forecast + battery_soc_init parameters

Note: NordPool prices already include distribution + VAT — no fixed offset is added.

---

Key Sensors

Role	Entity ID	Notes
PV Power	sensor.deye_inverter_mqtt_dc_total_power	DC total from strings
Load Power	sensor.deye_inverter_mqtt_total_load_power	House consumption
Grid Power	sensor.deye_inverter_mqtt_total_grid_power	+import / -export
Battery SOC	sensor.deye_inverter_mqtt_battery_soc	%
Battery Power	sensor.deye_inverter_mqtt_battery_power	+discharge / -charge
NordPool	sensor.nordpool_kwh_lv_eur_3_10_021	Spot price EUR/kWh
PV Forecast	sensor.p_pv_forecast	EMHASS output
Load Forecast	sensor.p_load_forecast	EMHASS output
Grid Forecast	sensor.p_grid_forecast	EMHASS output
SOC Forecast	sensor.soc_batt_forecast	EMHASS output — planned end-of-day SOC (always = target 60%)

---

Sign Conventions

Sensor	Positive	Negative
battery_power	Discharging to load	Charging from PV/grid
total_grid_power	Importing from grid	Exporting to grid
inverter_l*_power	Export to grid	Import from grid

---

Comparison: Forecast vs Reality

Template Sensors Created

Sensor	Description
sensor.battery_soc_forecast_error	Actual SOC - Forecast SOC (%)
sensor.current_hour_price	Current hour's electricity price (€/kWh)

Monitoring Dashboard

Add the dashboard card from dashboard_card.yaml:

1. Go to Dashboard → Edit → Add Card → Manual
2. Paste the YAML content

Checking Performance

Daily comparison questions:

1. Did battery charge during cheap hours (00:00–05:00, 12:00–14:00)?
2. Did battery discharge during peak hours (19:00–22:00)?
3. Is sensor.battery_soc_forecast_error within ±5%?

If error > 10%:

• Check if Deye inverter is overriding EMHASS decisions
• Consider adding enforcement automation (see below)

History Graph

Compare actual vs forecast over time:

type: history-graph
entities:
  - entity: sensor.deye_inverter_mqtt_battery_soc
    name: Actual SOC
  - entity: sensor.soc_batt_forecast
    name: Forecast SOC
hours_to_show: 48

---

Adding EV Charging (OpenEVSE)

When the EV charger is integrated:

1. Create a sensor for EV power (or use OpenEVSE integration):

   # In configuration.yaml
   sensor:
     - platform: template
       sensors:
         ev_charger_power:
           friendly_name: "EV Charger Power"
           value_template: "{{ states('sensor.openevse_current_power') | float(0) * 230 }}"
           unit_of_measurement: "W"
   

2. Create a template sensor that subtracts EV from total load:

     - platform: template
       sensors:
         load_power_no_var_loads:
           friendly_name: "Load Power (no EV)"
           value_template: "{{ states('sensor.deye_inverter_mqtt_total_load_power') | float - states('sensor.ev_charger_power') | float(0) }}"
           unit_of_measurement: "W"
   

3. Update EMHASS config:

   "sensor_power_load_no_var_loads": "sensor.load_power_no_var_loads",
   "number_of_deferrable_loads": 1,
   "nominal_power_of_deferrable_loads": [7400],
   "operating_hours_of_each_deferrable_load": [6]
   

4. Restart EMHASS

---

Troubleshooting

EMHASS logs show "config.json does not exist"

The config file must be at:

/addon_configs/5b918bf2_emhass/config.json

Not at /homeassistant/config.json or /config/config.json.

"Shape of passed values is (X, 1), indices imply (48, 1)"

Load sensor has insufficient history. EMHASS needs ≥48 data points (24h at 30-min resolution). Either:

• Wait for more history to accumulate
• Switch to sensor.deye_inverter_mqtt_total_load_power (has months of history)

Check EMHASS status via SSH

ssh root@192.168.66.113
ha addons logs 5b918bf2_emhass | tail -30
ha addons restart 5b918bf2_emhass

Verify NordPool prices are being passed

curl -s -X POST http://192.168.66.113:5000/action/dayahead-optim \
  -H "Content-Type: application/json" \
  -d '{"load_cost_forecast": [0.20, 0.19, ...]}' 

Check logs for: Passed runtime parameters: {'load_cost_forecast': [...]}

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Files in This Repository

File	Purpose
config.json	EMHASS configuration (deploy to HA)
config_emhass.yaml	Human-readable reference (same config)
migration_log.md	Migration notes from Domoticz
README.md	This file

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References

• EMHASS Documentation
• EMHASS GitHub
• Deye Inverter MQTT Integration
• NordPool Integration