Solar iBoost: How to get free hot water from your solar panels

How does the solar iBoost work and how can you get hot water from your solar panels? We explain more.

What is a Solar iBoost?

The Solar iBoost is an intelligent energy diverter that automatically uses excess solar electricity to heat your hot water instead of exporting it to the grid. This clever device can significantly increase your solar self-consumption and provide free hot water throughout much of the year.

How It Works

Monitors solar generation continuously

Detects excess power not being used in home

Diverts surplus electricity to immersion heater

Heats water cylinder with free solar energy

Reduces gas/oil usage for water heating

The Technology Behind Solar iBoost

Smart Power Management

The iBoost+ uses advanced electronics to:

• Measure export flow at consumer unit
• Calculate available surplus in real-time
• Proportionally control immersion heater
• Prevent any grid import for water heating
• Respond instantly to household demand changes

Variable Power Control

Unlike simple on/off switches:
• Controls power from 0-3kW continuously
• Matches exact surplus available
• No flickering or interference
• Smooth, proportional heating
• Maximum energy utilization

Benefits of Installing Solar iBoost

Financial Savings

Typical UK household savings:
• £200-300 annually on water heating
• Reduced gas/oil consumption by 50-90%
• Less wear on boiler extending its life
• Higher solar self-consumption up to 90%
• Payback period typically 2-3 years

Environmental Impact

• Reduces carbon emissions
• Less fossil fuel dependency
• Maximizes renewable energy use
• Supports grid stability
• Contributes to net-zero goals

Practical Advantages

• Hot water available all day
• Works automatically
• No user intervention needed
• Silent operation
• Maintenance-free design

Compatible Systems

Hot Water Cylinders

Solar iBoost works with:
• Vented cylinders: Direct connection
• Unvented cylinders: With immersion heater
• Thermal stores: Multiple immersion points
• Twin coil cylinders: Uses top immersion

Immersion Heater Requirements

• Standard 3kW immersion heater
• Must be thermostatically controlled
• AC immersion (not DC)
• Properly earthed installation

Not Compatible With:

• Combi boilers (no cylinder)
• Instantaneous water heaters
• DC immersion heaters
• Swimming pool heaters (need different product)

Installation Process

Professional Installation

Typically takes 2-3 hours:
• CT sensor installation at consumer unit
• Sender unit mounting near consumer unit
• Wireless pairing with immersion controller
• Immersion connection via relay box
• System commissioning and testing

DIY Considerations

While possible for competent DIYers:
• Electrical work must comply with Part P
• Requires consumer unit access
• Understanding of electrical systems needed
• Professional installation recommended
• Warranty may require certified installer

Solar iBoost+ Features

Latest Model Advantages

The iBoost+ (current model) offers:
• Wireless operation: No cable runs needed
• Boost button: Manual water heating
• LED display: Shows diversion amounts
• Multiple outputs: Can control two immersions
• Smart integration: Works with home automation

Monitoring Capabilities

Track your savings with:
• Daily energy diverted display
• Historical data storage
• Estimated savings calculator
• System status indicators
• Fault diagnostics

Real-World Performance

Seasonal Variations

Typical UK diversion amounts:
• Summer: 8-15 kWh daily
• Spring/Autumn: 3-8 kWh daily
• Winter: 1-3 kWh daily
• Annual total: 1,000-2,000 kWh

Case Study Results

4kW solar system with iBoost:
• Previously exported: 1,500 kWh annually
• Now diverted to hot water: 1,200 kWh
• Gas savings: £250 per year
• Export income lost: £60
• Net benefit: £190 annually

Cost Analysis

Purchase and Installation

Current UK pricing:
• Solar iBoost+ unit: £300-400
• Professional installation: £150-250
• Total investment: £450-650
• Optional accessories: £50-100

Return on Investment

• Average annual savings: £200-300
• Payback period: 2-3 years
• 10-year savings: £2,000-3,000
• No maintenance costs
• 10-year manufacturer warranty

Comparison with Alternatives

Vs Battery Storage

Solar iBoost advantages:
• Much lower initial cost
• No degradation over time
• Simpler installation
• No replacement needed
• Specific use case (hot water)

Battery advantages:

• Stores electricity for any use
• Works during power cuts
• Higher overall savings potential
• Time-shifting capability

Vs Other Diverters

• Eddi: More features but pricier
• immersun: Similar but discontinued
• Power Reducer: Basic functionality
• Apollo Gem: Good alternative

Common Questions

"Will it work on cloudy days?"

Yes, but with reduced effectiveness. Even 500W of excess solar can contribute to water heating over time.

"Does it affect my FiT payments?"

No, FiT payments are based on generation, not export. You still receive full generation payments.

"Can it heat water to full temperature?"

Yes, given enough solar excess. The immersion thermostat controls maximum temperature as normal.

"What about legionella risk?"

Your existing system controls (60°C weekly heating) remain in place and function normally.

Optimizing Your Solar iBoost

Best Practices

• Set immersion thermostat to 60-65°C
• Use timer for backup heating if needed
• Position cylinder thermostat correctly
• Insulate hot water pipes
• Consider cylinder upgrade if old

System Integration

Works well with:
• Time-of-use tariffs
• Solar batteries (with priority settings)
• Heat pumps (reducing running time)
• Smart home systems
• Energy monitoring

Who Should Consider Solar iBoost?

Ideal Candidates

• Homes with hot water cylinders
• Solar systems over 3kW
• High daytime export rates
• Families using lots of hot water
• Those seeking quick payback

Less Suitable For

• Combi boiler users
• Very small solar systems
• Homes with solar batteries
• Low hot water usage
• Off-grid properties

Professional Installation Benefits

Why Use CRG Direct

• Experienced installers
• Correct system sizing
• Warranty protection
• Integration advice
• Ongoing support

Package Deals

Often available:
• Combined with solar installation
• Discounted pricing
• Single point of contact
• Comprehensive warranties
• Optimized system design

Future Developments

Smart Grid Integration

Coming features:
• Dynamic export pricing response
• Grid service participation
• AI-powered optimization
• Weather forecast integration
• App-based control

Product Evolution

Expected improvements:
• Higher power ratings
• Multiple appliance control
• Better monitoring
• Lower costs
• Enhanced connectivity

Conclusion

The Solar iBoost represents an excellent way to maximize the value of your solar panels by converting excess generation into useful hot water. With typical payback periods of just 2-3 years and the prospect of free hot water for decades to come, it's a smart addition to most solar installations with compatible hot water systems.

For homes with hot water cylinders, adding a Solar iBoost can increase solar self-consumption from 30-40% to 70-90%, dramatically improving the economics of solar power. The simple, reliable technology requires no maintenance and provides immediate, tangible benefits in reduced energy bills.

Contact CRG Direct to discuss whether Solar iBoost is right for your home and how it can be integrated with your new or existing solar panel system.