Greece is preparing a substantial revision of its net-billing and virtual net-billing framework after the existing system failed to deliver the expected level of investment in solar self-consumption. The Ministry of Environment and Energy has opened consultation on amendments aimed at addressing practical problems that emerged after the current rules took effect in September 2024. The proposed changes cover rooftop solar, batteries, virtual net billing, zero-export installations and small balcony systems.
Scope of the consultation on distributed generation and storage
The consultation includes provisions for battery systems installed alongside self-consumption solar on the interconnected network. Under the draft rules, such batteries would be allowed to export stored electricity. They would not be permitted to charge directly from the grid.
The Ministry’s approach is designed to separate self-consumption batteries from merchant storage in operational terms. A battery paired with an associated solar installation could store electricity generated by that system and later export it. However, it could not purchase low-priced electricity from the network for resale during higher-priced periods.
Grid-charging limits in virtual net billing and conventional schemes
Industry representatives broadly accept the grid-charging restriction for virtual net-billing projects. They also question how the same limitation would apply to conventional net billing and zero-export installations. In those cases, preventing grid charging may affect demand management and reduce a battery’s ability to support customers when solar production is unavailable.
Standalone batteries installed by households and businesses would also be permitted under the draft, provided they do not export electricity to the grid. Their storage capacity could not exceed the consumer’s contracted connection capacity. The rules are intended to reduce potential network impacts while shaping how storage assets can be used commercially.
Balcony solar cap and cost concerns
The draft also sets 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 focus on additional technical requirements that could raise installation costs relative to the small system size.
For an 800 W installation, even modest compliance, metering or equipment costs could materially lengthen the payback period. The reforms are expected to improve the regulatory position of distributed storage, but investment growth would depend on implementation by network operators, connection timelines, metering arrangements and supplier billing practices.
Net-billing reform is described as commercially meaningful only when customers can predict how generated, stored, consumed and exported electricity will be valued.
