Prosumer, Pro-payer: The Solar Battery for Escaping the Trap

In Belgium, many owners of photovoltaic installations now find themselves in a paradoxical situation: they invested in solar energy to save money, but end up paying more than before. How can a solar battery transform this equation and help you escape the prosumer tariff trap?

The Bidirectional Meter Trap: When Savings Turn into Costs

For the majority of Belgian owners of older photovoltaic installations benefiting from bidirectional metering (net metering), battery storage is generally not yet economically justified. As long as your annual production fully covers your energy needs, the electricity grid effectively acts as a free "giant battery".

This situation mainly applies to well-sized installations that produce exactly what they consume on an annual basis. In this specific case, the compensation system still works to your advantage.

"I have a 6 kW installation that perfectly covers my annual needs. With the meter running backwards, I have no economic interest in adding a battery at this time." - Wattuneed customer testimonial

"Energy Deficits": Victims of a Double Penalty

If your photovoltaic installation does not fully cover your annual needs, you incur a double cost that can quickly reach several hundred pounds per year:

• Annual prosumer tax based on your installed capacity (kWp) - often very high depending on your network operator
• Purchase of additionalelectricity at particularly expensive grid rates
• Compensation costs that accumulate month after month

This situation affects a growing number of Belgian prosumers whose installation was initially poorly dimensioned or whose consumption has changed (electric vehicle, heat pump, etc.).

Calculation of the double penalty

The Battery Solution: Switch to Dynamic Pricing

By abandoning the compensation system and adopting dynamic tariffs, you permanently eliminate the prosumer tax based on your installed capacity. The aim is not to sell electricity, butto eliminate this annual tax, which can amount to hundreds of pounds per year.

How does this strategy work?

Your solar battery then allows you to:

1. Be completely self-sufficient on sunny days by storing your production
2. Purchase electricity at the cheapest times (typically at night) the rest of the time
3. No longer pay the prosumer tax, regardless of your level of production
4. Optimise your costs thanks to hourly tariff variations

Discover our Delong Top Energy 5.12kWh lithium battery, perfectly suited to this energy optimisation strategy.

Daily Profitability: An Investment that Pays Off 365 Days a Year

Contrary to popular belief, a properly sized solar battery generates savings 365 days a year:

Sunny Days: Free Storage

• Free storage of your solar production
• Use in the evening without drawing on the grid
• Complete autonomy on favourable days

Less Favourable Days: Tariff Arbitrage

• Purchase at night at low rates (often 50% cheaper)
• Use during the day at peak times
• Continuous optimisation of energy costs

All year round: Prosumer tax exemption

• Guaranteed fixed savings on taxation
• No more charges based on installed capacity
• Total freedom of consumption

"Since I installed my Wattuneed battery and switched to the dynamic tariff, I've saved over £800 per year. The battery is profitable even on days without sunshine!" - Wattuneed customer, Liège

The Favourable Economic Equation: Unbeatable Storage Costs

With current battery costs, the economic equation has become extremely favourable:

Concrete example with a 5kWh battery

With a usage cost of only £0.037 per kWh, any use of the battery becomes profitable compared to high grid tariffs (0.25-0.35/kWh), transforming each charge/discharge cycle into direct savings on your energy bill.

Wattuneed Solutions: The Best Products for Your Strategy

High-Performance Lithium Batteries

Our Delong Top Energy lithium battery offers the best value for money on the market:

• 5.12kWh capacity: ideal for a family home
• Modular stackable design: scalable according to your needs
• Ultra-fast installation: set up in less than 5 minutes
• Universal compatibility: works with all hybrid inverters
• 10-year warranty: peace of mind guaranteed

Discover the Delong Top Energy 5.12kWh battery

Solar kits with integrated storage

For a complete solution, our solar kits with hybrid inverter and battery offer you a turnkey installation:

• 12-panel 5kVA kit with lithium storage
• 25-panel 10kVA kit with lithium storage
• 6-panel hybrid kit with storage

Real-world use cases: Who can benefit from this strategy?

The Philippe Family (8kW installation - Deficit consumption)

• Situation: Photovoltaic installation that only covers 70% of annual needs
• Problem: Prosumer tax of €688/year + €450 in grid purchases
• Solution: 5kWh battery + switch to dynamic pricing
• Result: Savings of £650/year from the first year

Installation and support: Wattuneed expertise

At Wattuneed, we support you in your transition to energy independence:

Free personalised assessment

• Analysis of your current consumption
• Assessment of your existing installation
• Precise calculation of potential savings
• Optimal sizing of your storage solution

Tailored Technical Solutions

• Latest generationhybrid inverters (Deye, Sofar, WKS)
• High-performancelithium batteries (Delong, Pylontech, SMA)
• Monitoring systems for real-time optimisation
• Certifiedprofessional installation

Discover our hybrid inverters

FAQ: Your questions about storage and the prosumer tax

Can I install a battery on my existing system?

Yes, our lithium batteries are compatible with most existing inverters. If your inverter is not hybrid, we offer retrofit solutions to integrate storage into your current installation.

How long does it take to recoup the cost of a solar battery?

For a Belgian prosumer paying the prosumer tax and purchasing additional electricity, the payback period is generally between 3 and 5 years, depending on the size of the installation and the level of energy deficit.

Is switching to dynamic pricing advantageous in all cases?

No, only prosumers whose installation does not cover 100% of their annual needs would benefit from abandoning compensation. A personalised study is necessary to assess your specific situation.

What battery capacity should I choose for my home?

For a standard family home, a capacity of 5 to 10kWh is generally optimal. Our modular Delong 5.12kWh battery allows you to start small and scale up according to your needs.

Do batteries require a lot of maintenance?

No, the LiFePO4 lithium batteries we offer do not require any special maintenance. The integrated management system (BMS) provides automatic protection and optimisation.

Conclusion: Turn your installation into a money-saving machine

Home storage is no longer a technology of the future, but an economic reality for strategic Belgian prosumers. By combining a high-performance solar battery with the switch to dynamic tariffs, you can turn your loss-making photovoltaic installation into a real money-saving machine.

With historically low storage costs and potential savings of several hundred pounds per year, the equation is clear: it's time to escape the prosumer double taxation trap.

Contact our Wattuneed experts today for your free personalised assessment and find out how much you could save with a storage solution tailored to your situation.

Contact Wattuneed - Your Photovoltaic Solutions Expert

Wattuneed
Rue Henripré 12
4821 Andrimont
Belgium
📞 +32 87 45 00 34
📧 info@wattuneed.com

Monday to Friday, 8:30 a.m. to 5:00 p.m. - Have a question? Need assistance? Our team is here to help!