FoxESS + CTA

Solar Heating with FoxESS and CTA

Combine the power of your FoxESS PV system with your CTA heat pump for intelligent solar heating. Zerofy monitors your real-time solar production and automatically adjusts control to match your available surplus.

What is Solar surplus heating?

Solar surplus heating means your heat pump operates primarily with the electricity your solar panels produce. Instead of feeding excess power to the grid at low rates, you use it yourself – saving money and maximizing self-consumption.

With FoxESS + CTA via Zerofy:

• Automatic adjustment – Control follows solar production in real-time
• Smart scheduling – Combine solar usage with time-based rules
• Smart Mode – Uses forecasts of household consumption and solar production

How It Works

Dynamic Tariff Integration

Beyond solar surplus heating, Zerofy can optimize your CTA for dynamic electricity tariffs based on EPEX Spot or Nordpool prices (e.g., Tibber, aWATTar, Energinet) or any manually defined tariff schedule.

Unlike simple “cheapest hours” approaches, Zerofy’s Smart Mode goes further: it uses forecasts of your household consumption and solar production to find the overall optimum.

Learn more about Smart Mode

Why No Hardware Required?

Traditional solar controllers require a dedicated hardware box. Zerofy takes a different approach:

• Cloud-to-cloud integration – Connects directly to FoxESS and CTA cloud APIs
• No electrician needed – Setup takes minutes, not hours
• No upfront cost – Just download the app and connect
• Always up-to-date – New features added automatically