Why does Net Billing favor battery usage so much?

Because the sale of the midday surplus is usually done at a much lower price than the purchase of evening electricity, it is advantageous to store it rather than export it.

Is home solar still worth it in 2026?

Yes, but only with proper sizing, an emphasis on timing, and often with the addition of a battery to improve actual damping.

Net Billing vs. Net Metering: What now applies in Greece and how it affects your installation

If you had asked a friend of yours who put photovoltaics on his roof in 2022 how his system works, he would happily tell you: "The sun produces the electricity, I give it to PPC, I burn it at night and in the end I pay nothing!" This was the era of Net Metering. It was by far the most generous and profitable scheme for the consumer in Europe. But, like all too good things, it came to an end. In 2024 the legislation changed radically, causing a "shock" in the market, and we moved definitively to the Net Billing system.

Today, in 2026, Net Billing is the only option for new applications. As engineers, we understand the frustration of many owners who have "missed the train", but the reality is clear. Let's see in simple terms what the differences are, why the State pulled the plug on the old system, and how you need to design your system today to win.

The "Golden" Past: How Net Metering Worked

In Net Metering, the transaction currency was the Kilowatt hour (kWh).

If at noon your panel produced 10 kWh (which you did not consume because you were away at work), you "sent" it to the DEDDIE network.
In the evening when you came back and turned on the water heater and oven, you "pulled" 10 kWh from the grid.
In the end, DEDDIE did the subtraction: 10 - 10 = 0. You paid nothing for the electricity.

In practice, DEDDIE acted as a huge, free, 100% efficient battery for your home.

Illustration for The "Golden" Past: How Net Metering Worked

The New Reality (2026): How Net Billing Works

In Net Billing, the transaction currency is no longer energy, but Money (Euro). The settlement is made at the cashier. And here lies the huge pitfall of the price difference:

You don't need to be an accountant to understand that if you sell your electricity for €0.04 during the day and buy it for €0.15 at night, the system is in trouble.

The Agora

The night you need electricity, you buy it from your provider at the normal retail price (e.g. €0.15 / kWh).

The Sale

At midday, the excess power from your panels and you throw it into the grid, you "sell" it at the wholesale price of the Energy Exchange. But because at noon all of Greece has sun and produces plenty of electricity, the wholesale price collapses (often reaching zero). Thus, you sell your electricity "yearly" (e.g. €0.04 / kWh or even less).

Why did the State change it? (The "Crash" of the Network)

The change was not made simply to lose the consumer, but out of technical necessity. The network couldn't take it anymore. When all the Greeks installed photovoltaics and threw their surplus into the grid at 1:00 pm (at that time nobody burns that much electricity in their house), DEDDIE had nothing to do with it. The cables were overloaded.

The state implemented Net Billing to financially "force" you not to dump your electricity on the street at noon, but to store or consume it on site.

Illustration for Why did the State change it? (The "Crash" of the Network)

The 3 New Rules of Survival in the Age of Net Billing

Designing a photovoltaic system today requires a completely different philosophy than 3 years ago. The rules are:

1. The "King" is called Synchronicity

The only way to make maximum profits is to consume the power at the exact moment it is generated. This is how you save €0.15 of the retail charge! Change of Habits:* The washing machine, the dishwasher and the solar water heater (with resistance) should no longer be switched on at night with the "night" current. They must be timed to run between 11:00 and 15:00, "sucking" your roof's sun directly.

2. Battery is not a luxury, it is a liability (practically)

In Net Billing, a PV system without a home battery is usually a bad investment. You definitely need a battery (eg 5kWh or 10kWh) to store the cheap/cheap midday power and give it to you from 7pm onwards so you don't have to buy any expensive power from the provider in the evening peak.

3. No more huge, oversized roofs

In the old system, many people put a huge photovoltaic (eg 10 kW) on a small house, so as to "store" thousands of kilowatt-hours for the winter. In Net Billing, this is prohibited. If you generate much more electricity than you burn (and sell it at dirt prices), you just made a very expensive installation that will never pay for itself. The system must be "tailored" exactly to the measures of your annual needs.

In summary: Is 2026 worth it after all?

The answer is Yes, it is clearly worth it. The sun remains free. The difference is that the payback period (ROI) of the investment has increased. While in the golden days of Net Metering you could pay back in 3 to 4 years, today, with Net Billing and the necessary cost of adding a battery, the payback time for a home system is typically 5 to 7 years. But since the panels have a life expectancy of 25 years, you have nearly two decades of net, tax-free profit and energy independence ahead of you.

Next Step: Since the rule in the new system is "surgical" precision and not exaggeration, how do we find the right size? Continue to our handy guide: How to Calculate the PV and Battery you need on Net Billing (Without Throwing Money Away).

Electrical Panel Requirements for Rooftop PV: What Your Electrician Should Add Hybrid Inverters: What they are and why they are the heart of every modern system Interfacing Batteries to the House Panel: AC Coupling vs. DC Coupling – Simplified guide Home Energy Storage vs. Generators: The future of backup and cost comparison

Electrical Supply, Power & Autonomy

Return to category.

Go to category

Central Guide

Return to the central guide.

Go to guide