A few panels on the balcony railings, a cable plugged into a socket and a smaller electricity bill. So-called plug-in solar panels, already widespread in Germany and central Europe, are now legal in Greece.

The framework is set out in ministerial decision ΥΠΕΝ/ΔΑΠΕΕΚ/102876/1958 (Government Gazette Β΄ 5573/14.09.2026), while HEDNO has issued specific technical specifications for their installation and connection.

But “plug and play” does not mean “without rules”. There are power limits, bans on using multiway adaptors and extension leads, a requirement to notify the network operator and a declaration signed by an electrician. Here is a step-by-step guide to the rules, based on the practical guide issued by the Hellenic Association of Photovoltaic Companies (SEF).

What is allowed: the key limits

The system is intended solely for self-consumption, meaning it covers part of the electricity used by the home. It is not an investment in solar panels that sells electricity to the grid.

What a kit includes

• Solar panels. At least one, with a total capacity of up to 1,000 W. They generate direct current (DC).
• Micro-inverter. Converts direct current into 230 V / 50 Hz alternating current, allowing it to feed into the home’s electrical installation. It is attached to the panel, a mounting frame or the wall, and is usually controlled via a mobile app over Wi-Fi or Bluetooth.
• Cable with plug. A special, durable cable ending in a Schuko plug that fits into an indoor or outdoor socket.
• Mounting frame. It must withstand not only the weight of the panels but also strong winds, earthquakes and snow.
• Battery (optional). Stores energy generated at midday for use in the evening. The manufacturer must state which panels and inverter it is compatible with.

Users can assemble the system themselves, following the manufacturer’s instructions. They can also move it to another socket or take it with them to another home, making it an attractive option for tenants. However, every time it is moved, the technical specifications and the requirement to notify the network operator apply again.

Where to put them (and where not to)

Despite the nickname “balcony solar panels”, they can also be installed on a roof terrace, on a wall or as a canopy above the balcony door. The ideal position is unshaded, facing south and tilted at about 25°-30°. In these conditions, each kilowatt of capacity generates about 1,500 kilowatt-hours a year in Greece.

As a general rule, avoid north-, north-east- and north-west-facing positions. In apartment blocks, take care on lower floors, where neighbouring buildings are more likely to cast shade. Importantly, panels hanging vertically from railings (at a 90° tilt) generate significantly less electricity.

Source: SEF, “Plug-in solar panels – A practical guide for consumers”, November 2026

Five things not to do

• Do not use multiway adaptors or extension leads. The plug must go directly into a fixed Schuko socket, either surface-mounted or flush-mounted.
• Do not overload the circuit. The cables and other sockets on the same circuit must not exceed the permitted loads.
• Do not tamper with the consumer unit yourself. Any work on the electrical installation must be carried out by a licensed electrician. If the consumer unit is changed or work is done that affects electrical safety, a new Installer’s Responsible Declaration (YDE) is required.
• Do not splice cables. If the cable is too short, use a single outdoor-rated extension cable (IP44 protection or higher) of the appropriate cross-section, with no cuts or joins.
• Do not improvise with the battery. It must be connected without tools, using only certified, factory-made quick-connect plugs (MC4 type).

The process, step by step

Even if you install the system yourself, you will need a suitably qualified electrician or engineer to certify in a responsible declaration that the specifications have been met.

1. Purchase. When buying the kit, either in a shop or online, give the seller the details of the electricity supply to which it will be connected, if possible. The seller is required to notify HEDNO without delay.
2. Register on HEDNO’s online portal. Before installation, log in to the dedicated digital portal using your Taxisnet credentials and provide your details (tax identification number, full name, contact details and installation address), the details of the electrician or engineer, the supply number and the system’s technical specifications. Legal entities must also provide their name, registered office and legal representative.
3. Documents. You need a valid Installer’s Responsible Declaration (YDE) for the home and a responsible declaration from the electrician or engineer confirming that HEDNO’s specifications have been met.
4. Connection. No connection agreement is signed, no other permit or approval is required, and no connection fee is charged.

In the Non-Interconnected Islands, the seller and the applicant submit the same information electronically. Before buying, it is worth checking the latest version of HEDNO’s technical specifications.

How much could you save?

The savings depend mainly on when you use electricity. The panels generate power around midday, so people who are out of the house until the afternoon use less of what they produce. Electricity that is not consumed as it is generated is fed into the grid and does not reduce the bill, since the system is intended solely for self-consumption.

SEF calculated the savings from an 800 W system in two positions: vertically on a balcony (about 720 kilowatt-hours a year) and at the ideal tilt and facing south (about 1,200 kilowatt-hours). The calculation uses an electricity price of 24 cents per kilowatt-hour, the Eurostat average for the first half of 2026 for households consuming 2,500-4,999 kWh.

Indicative calculations using an electricity price of 24 cents/kWh. Source: SEF, November 2026

The conclusions are clear. A typical household using 4,000 kWh a year saves €150-245 annually without a battery, cutting its bill by 16%-26%. With a small 2 kWh battery and a dynamic tariff, the savings rise to €290 and the reduction to 31%.

By contrast, for people who are out of the house during the sunniest hours, a system without a battery delivers modest savings of just €60-68 a year, even in an ideal position. This is where a battery makes the difference: it stores the midday output for the evening and can double or even triple the savings, to €125-215. The other major factor is position. For a typical household, moving the panels from vertical railings to a south-facing position at an angle increases savings by about 60%.

*See the full practical guide from SEF in the “Accompanying Material” column on the right.