Greece is preparing a substantial revision of its net-billing and virtual net-billing framework after the existing system failed to generate the expected level of investment in solar self-consumption.
The Ministry of Environment and Energy has opened consultation on amendments intended to resolve practical problems that emerged after the current rules took effect in September 2024. The reforms cover rooftop solar, batteries, virtual net billing, zero-export installations and small balcony systems.
The Hellenic Association of Photovoltaic Companies has supported the direction of the changes, arguing that the self-consumption market has achieved limited growth over the past two years. The main issue has been less the attractiveness of solar technology than the complexity of turning distributed generation and storage into a financeable customer proposition.
Under the proposed rules, batteries installed with self-consumption systems on the interconnected network would be allowed to export stored electricity. They would not, however, be permitted to charge directly from the grid.
The restriction creates a clear separation between self-consumption batteries and merchant storage. A battery would be able to store electricity generated by the associated solar installation and later export it, but it could not buy low-priced electricity from the network for resale during higher-priced periods.
Industry representatives broadly accept this treatment for virtual net-billing projects but question its application to conventional net billing and zero-export installations. In those cases, preventing grid charging may limit demand management and reduce the battery’s ability to support the customer during periods when solar production is unavailable.
Standalone batteries installed by households and businesses would also be permitted, provided they do not export electricity to the grid. Their storage capacity could not exceed the consumer’s contracted connection capacity.
These rules reduce potential network impacts but also constrain the commercial use of the asset. A customer may install storage to reduce peak consumption, improve resilience and increase self-consumption, but would not have access to the full revenue stack available to a merchant battery.
The draft also establishes a maximum capacity of 800 W for balcony solar systems used in residential and building-mounted applications. These installations would operate on a zero-export basis.
Industry concerns centre on additional technical requirements that could raise installation costs relative to the small size of the system. For an 800 W installation, even modest compliance, metering or equipment costs can materially lengthen the payback period.
The reforms should improve the regulatory position of distributed storage, but investment growth will depend on implementation by network operators, connection timelines, metering arrangements and the ability of suppliers to offer transparent billing. Net-billing reform becomes commercially meaningful only when the customer can predict how generated, stored, consumed and exported electricity will be valued.
