Powering Your Smart Home with Solar: The Lenovo Home Assistant Hub

In an era where energy independence and smart living are increasingly intertwined, harnessing solar power to fuel your home appliances is a game-changer. This article explores how a compact yet powerful Lenovo M75 or M95 Small Form Factor (SFF) computer can serve as the central brain for your home automation, specifically focusing on optimizing solar energy usage.

Why a Lenovo SFF for Home Assistant?

While Raspberry Pis are popular for Home Assistant, a Lenovo SFF offers significant advantages for a more robust and stable setup, especially when dealing with data-intensive tasks like energy monitoring:

Reliability: These business-grade machines are built for continuous operation, offering superior stability compared to consumer-grade microcontrollers.
Performance: With more powerful processors (e.g., AMD E-series or Intel Core i3/i5/i7 in some configurations) and ample RAM, they can handle numerous integrations, data logging, and complex automations without breaking a sweat.
Storage: They typically come with or support M.2 SSDs, providing faster and more reliable storage than microSD cards, crucial for a Home Assistant database.
Connectivity: Plentiful USB ports allow for easy expansion with Zigbee/Z-Wave dongles, Modbus adapters, and other sensors.
Power Efficiency: Despite their enhanced performance, many M75/M95 models are surprisingly power-efficient, consuming only a few watts at idle, making them ideal for always-on home server roles.

Setting Up Home Assistant

First, install Home Assistant OS on your Lenovo . This can be done by flashing the image to an SSD and booting from it. Once Home Assistant is running, you’ll gain access to its intuitive interface for managing your smart home.
If you are not sure how to do this you can purchase one from our shop which is already loaded with Home assistant.

Gathering Solar, Battery, and Home Power Data

The key to intelligent solar usage lies in accurate data collection. Home Assistant excels at integrating with various devices to provide a comprehensive energy overview:

1. Inverter Integration: The inverter is your solar system’s brain, providing crucial data on solar generation, battery charge/discharge, and grid import/export. Popular inverter brands with good Home Assistant integration include:

Fronius: Known for its local API and extensive data points, offering excellent integration through the Fronius integration.
SolarEdge: Can be integrated via Modbus TCP, providing detailed insights into panel-level optimization and overall system performance.
SolaX: Offers Modbus integration for pulling data.
GivEnergy: Well-supported within Home Assistant, providing easy access to battery and inverter data.
Growatt: While some models might require DIY solutions like flashing Solar Assistant onto a Raspberry Pi to then bridge data via MQTT, direct integrations are improving. We do make a device for Growatt inverters.
Huawei Sun2000: Integrates well via the FusionSolar API or local Modbus.
Victron Energy: Highly regarded for its robust off-grid and hybrid systems, with excellent Home Assistant integration options, often through MQTT.

You’ll typically connect to your inverter either directly over Ethernet (if supported) or via a USB/RS485 adapter connected to your Lenovo, communicating through protocols like Modbus TCP. Some integrations work with the apps and this can be seamless and easy to do.

2. Energy Monitoring: Beyond your inverter, dedicated energy meters can provide granular data on your home’s overall consumption and individual circuits:

Shelly EM / Shelly 3EM: These DIN-rail mountable devices use Current Transformer (CT) clamps to measure power consumption at your main incoming grid line or individual circuits. They integrate seamlessly with Home Assistant via MQTT or their local API.
IAMMETER Wi-Fi Energy Meters: Offer real-time energy monitoring with integration options via MQTT, Modbus/TCP, or native Home Assistant integration.
Home Assistant Glow / SlimmeLezer+: For users in countries with P1 ports on their smart meters, these ESPHome-based devices provide direct integration with grid consumption data.

Smart Switch Management for Solar Optimization

This is where the power of Home Assistant truly shines. By combining solar generation data with real-time home consumption, you can intelligently manage your high-power appliances.

Popular Smart Plugs/Switches with Power Monitoring:

Shelly Plug S / Shelly Plus Plug PM: Compact smart plugs with integrated power monitoring, ideal for individual appliances.
Sonoff POW Origin / Sonoff POW Elite: Affordable smart switches with power monitoring capabilities, often flashable with Tasmota firmware for local control and robust Home Assistant integration.
TP-Link Kasa Smart Plugs (e.g., KP115): Many Kasa plugs offer energy monitoring and local control, though some models might rely more on cloud services.
Zigbee/Z-Wave Smart Plugs: Brands like Aqara, Aeotec, and Innr offer smart plugs with power monitoring that integrate via a Zigbee or Z-Wave dongle connected to your Home Assistant hub.
RenewSolar provide and also custom build monitoring devices for all aspects of solar.

Automation Scenarios (using Home Assistant’s automation engine):

Washing Machine/Dishwasher Activation:
- Trigger: Solar surplus (e.g., sensor.RenewSolar_current_power_export > 1000W for 5 minutes).
- Condition: Battery state of charge (if applicable) is above a certain threshold (e.g., sensor.RenewSolar_battery_soc > 90%) OR grid export is high.
- Action: Turn on switch.washing_machine_plug (a smart plug connected to your washing machine).
- Further Refinement: Add conditions like “only run if laundry mode is enabled” (a Home Assistant input boolean) or “don’t run if it’s past 4 PM.”
- Feedback: Send a notification to your phone via the Home Assistant Companion App when the appliance starts or finishes.
Water Heater Automation:
- Trigger: Significant solar surplus detected (e.g., sensor.fronius_power_flow_grid_export > 2000W).
- Condition: Water heater temperature is below desired setpoint, or battery is full.
- Action: Turn on switch.immersion_heater_relay (a high-power smart relay for your immersion heater).
- Stop Condition: Turn off the relay if solar export drops below a threshold, or if the water temperature reaches its setpoint.
EV Charging with Solar Surplus:
- Trigger: Available solar surplus (total generation – home consumption) exceeds the minimum charging rate for your EV.
- Condition: EV is plugged in and ready to charge.
- Action: Adjust the charging current of your EV charger (e.g., a Zappi or Wallbox Pulsar Plus with Home Assistant integration) to match the available solar surplus.
- Creative Example: Prioritize charging the EV when electricity prices are highest (if on a variable tariff) and solar is abundant, then switch to slower, purely solar-driven charging when prices are low or solar is less plentiful.

Integrating with Google Home Hub

Your Google Home Hub can become a powerful interface for your Home Assistant setup.

Integration Steps (using Home Assistant Cloud or manual setup):

Home Assistant Cloud (Nabu Casa): This is the easiest and most recommended method. A paid subscription provides a secure, remote connection to your Home Assistant instance and automatically exposes your devices to Google Assistant. Simply enable the Google Assistant integration within Home Assistant Cloud settings. Certain other devices work for free, and can be controlled or listed vocally.
Manual Setup: For advanced users, you can configure Google Assistant integration manually using the Google Developers Console. This involves creating a project, enabling APIs, and setting up credentials. While free, it requires more technical know-how and ongoing maintenance through upgrades.

Creative Use Cases with Google Home Hub:

Voice Control for Solar Optimised Appliances:
- “Hey Google, start the washing machine with solar power.” (Home Assistant automation triggers based on solar availability).
- “Hey Google, how much solar power are we generating right now?” (Home Assistant reads inverter data).
- “Hey Google, tell me the battery percentage.”
Visualising Energy Flow: Create custom dashboards in Home Assistant that can be displayed on your Google Home Hub. Imagine seeing real-time graphs of solar production, home consumption, and battery status directly on your Nest Hub display.
Proactive Voice Notifications: Home Assistant can send notifications to your Google Home Hub speakers. For example:
- “Solar surplus detected! Consider running a heavy appliance now.”
- “Battery charged to 100%. Great day for solar!”
- “Grid import detected. Time to adjust appliance usage.”

Creative Use Cases Beyond the Basics:

Dynamic Heating/Cooling: If you have electric heating or air conditioning, Home Assistant can adjust thermostats based on solar availability. For instance, pre-heat your home during peak solar production hours, even if it’s slightly before you’d typically turn on the heating, to leverage free energy.
Smart Garden Irrigation: Automate your garden watering system to run only when there’s excess solar power available, minimizing reliance on grid electricity for irrigation.
Electric Shower Optimization: Integrate with smart electric shower controls to prioritize showering during periods of high solar generation, either by enabling the shower or pre-heating water with excess solar.
“Solar Laundry Day” Automation: Create a routine that sends a notification to your family on sunny days, suggesting it’s the ideal time to do laundry to maximize solar self-consumption. The automation could even trigger the washing machine automatically if clothes are detected as loaded (e.g., via a smart weight sensor in the drum or a smart dryer integration).
Load Shifting for EV Charging with Forecasts: Combine real-time solar data with weather forecasts (available via Home Assistant integrations) to predict future solar production. If tomorrow is expected to be sunny, Home Assistant can delay EV charging tonight to ensure maximum solar self-consumption for tomorrow’s charge.
“Export Maximizer” Mode: If you’re on a lucrative export tariff, Home Assistant can intelligently prioritize exporting excess solar power during peak tariff hours, even if it means slightly reducing battery charging or delaying appliance use.
Battery Wear Management: Implement automations to manage battery cycles. For instance, if your battery is regularly reaching 100% and holding, Home Assistant can subtly discharge it slightly by turning on a small load (like a water heater element) to prevent prolonged high-state-of-charge states, which can extend battery life.

By leveraging a robust Lenovo as your Home Assistant server, you unlock a world of possibilities for intelligent energy management, turning your home into a truly efficient and solar-powered smart living space. The journey to energy independence starts with smart data and smarter automation.

Need home automation, or minor data transmission and displays? RenewSolar could be the one you turn to for help.