Description
Geyserwise MWS ESPHome MPPT Solar Geyser Controller
Local Smart Control for Direct Solar PV Water Heating
Get the most from your solar PV system with the Geyserwise MWS ESPHome MPPT Solar Geyser Controller. Combining the proven efficiency of the Geyserwise Megawatt Saver (MWS) with professionally integrated ESPHome firmware, this controller brings fully local smart control and advanced Home Assistant automation to direct solar water heating.
Designed for solar PV-to-water heating systems, the MWS continuously tracks the maximum power point of your solar array, converting available solar energy directly into hot water with up to 99% MPPT efficiency. By replacing the standard communication module with ESPHome, you gain fast, reliable local control, real-time monitoring, and complete ownership of your data—without relying on cloud platforms or subscription services.
Whether you’re building an energy-independent smart home or optimising an existing solar installation, the Geyserwise MWS ESPHome Controller gives you powerful automation and maximum solar performance.
Need Geyserwise Accessories?
Looking for additional Geyserwise accessories such as flanges, probes, thermostats, sensors, or replacement parts? We can supply a wide range of genuine Geyserwise components. Simply email sales@smartpad.co.za with your requirements, and our team will be happy to assist you.
Native Home Assistant Integration
Every controller is professionally modified and pre-flashed with ESPHome, allowing seamless integration with Home Assistant.
Features include:
- Automatic Home Assistant discovery
- Native ESPHome support
- Fully local Wi-Fi communication
- Fast, responsive updates
- Easy firmware management through ESPHome
- No proprietary cloud services
Once connected to your network, the controller becomes a fully integrated Home Assistant device, ready for dashboards, automations, notifications, and energy management.
Advanced MPPT Solar Technology
The Geyserwise MWS uses Maximum Power Point Tracking (MPPT) to continuously optimise the output of your solar PV array.
Benefits include:
- Up to 99% MPPT efficiency
- Maximum energy harvesting
- Improved performance during changing weather
- Faster water heating
- Better utilisation of your solar panels
- Increased return on your solar investment
Instead of wasting available solar energy, the controller continually adjusts to extract the highest possible power from your PV array.
Direct PV-to-Water Heating
Designed specifically for direct solar PV water heating, the MWS converts electricity from your solar panels directly into heat.
Advantages include:
- Lower electricity consumption
- Reduced reliance on grid power
- Greater energy independence
- Efficient use of surplus solar generation
- Improved return on investment
Transform excess daytime solar production into stored hot water for later use.
100% Local Smart Control
Because ESPHome communicates directly with Home Assistant over your local network, you benefit from:
- No cloud dependency
- Complete data privacy
- Faster automation response
- Reliable operation during internet outages
- No monthly subscription fees
- Full ownership of your smart home
Your controller continues operating even if your internet connection is unavailable.
Powerful Home Assistant Automation
Use Home Assistant to build intelligent automations around your solar water heating system.
Monitor and control:
- Water temperature
- Solar PV heating status
- MPPT operation
- System performance
- Heating schedules
- Notifications and alerts
Example automations include:
- Heat water using surplus rooftop solar PV generation
- Pause heating during load shedding
- Optimise operation based on weather forecasts
- Integrate with battery state of charge
- Coordinate with home energy management systems
- Trigger notifications when temperatures reach target values
Perfect for advanced Home Assistant users looking to maximise self-consumption of solar energy.
Real-Time Monitoring
Monitor your system from intuitive Home Assistant dashboards.
View:
- Water temperature
- Controller status
- Heating activity
- Solar operating conditions
- Automation status
- Historical performance data
Integrate seamlessly with Home Assistant’s Energy Dashboard and custom dashboards for complete visibility of your hot water system.
Professionally Modified & Fully Supported
Every controller is professionally upgraded and thoroughly tested before dispatch.
Benefits include:
- Professional hardware modification
- ESPHome firmware pre-installed
- Fully tested before shipping
- Full product warranty
- Ready for installation
No soldering, flashing, or hardware modification is required.
Ideal Applications
✔ Direct Solar PV Water Heating Systems
✔ Home Assistant Smart Homes
✔ Residential Solar PV Installations
✔ Off-Grid Solar Systems
✔ Hybrid Solar Water Heating
✔ Energy-Efficient Homes
✔ Solar Self-Consumption Optimisation
✔ Smart Home Energy Management
Technical Highlights
| Specification | Details |
|---|---|
| Controller | Geyserwise MWS (Megawatt Saver) |
| Firmware | ESPHome (Pre-installed) |
| Smart Platform | Home Assistant |
| Connectivity | Wi-Fi |
| MPPT Efficiency | Up to 99% |
| PV Input Voltage | 120–350V DC |
| Heating Method | Direct PV-to-Geyser Element |
| Operation | Fully Local (No Cloud Required) |
Compatibility
The Geyserwise MWS ESPHome Controller is designed for direct solar PV water heating systems using compatible geyser elements and appropriately sized PV arrays.
Suitable for:
- Residential solar PV installations
- Off-grid systems
- Hybrid solar systems
- Existing Geyserwise MWS installations
Professional installation is recommended to ensure compliance with electrical regulations and optimal system performance.
Why Choose the Geyserwise MWS ESPHome Controller?
The Geyserwise MWS ESPHome MPPT Solar Geyser Controller combines industry-leading MPPT solar technology with the flexibility of ESPHome and Home Assistant, creating one of the most advanced locally controlled solar water heating solutions available. With up to 99% MPPT efficiency, native Home Assistant integration, cloud-free operation, and powerful automation capabilities, it’s the ideal choice for homeowners who want to maximise solar energy, reduce electricity costs, and build a truly intelligent, privacy-focused energy management system.
