Greece’s energy regulator RAAEY is preparing revised electricity-distribution loss coefficients following a report by network operator DEDDIE that average losses declined during 2024. The revisions are expected to reduce the volume of electricity suppliers must buy to cover network losses when serving customers. The regulator is also expected to adopt smaller reductions than those initially proposed by DEDDIE.
2024 loss trends and proposed coefficient changes
Average distribution losses fell from 11.2% to 10.81%. DEDDIE proposed lowering the medium-voltage loss coefficient from 4.59% to 4.35%. It also proposed reducing the low-voltage coefficient from 16.19% to 15.15%.
Under the existing low-voltage coefficient, a supplier delivering 100 kWh to customers would need to purchase 116.19 kWh to cover recognised network losses. The proposed coefficient would bring that requirement down to 115.15 kWh. While the difference is small for an individual consumer, it becomes financially material across millions of metered accounts.
Procurement impact and wholesale cost reference
For every 1 TWh of low-voltage consumption, the proposed reduction would lower recognised energy procurement by approximately 10.4 GWh. At a wholesale price of €100/MWh, that equates to more than €1 million in avoided procurement cost before balancing and settlement effects.
The procurement effect is linked to how recognised losses are calculated under the coefficients used for supplier supply obligations. Suppliers’ concerns extend beyond the headline changes in the medium- and low-voltage parameters. They focus on whether provisional losses will be reconciled later against actual system data.
Settlement reconciliation risk highlighted by 2022 case
Suppliers pointed to Greece’s experience in the first half of 2022, when differences between estimated and actual network losses led to additional charges of approximately €164 million over six months. That episode is cited as a reason suppliers are cautious about aggressive reductions that could result in large correction invoices later.
A coefficient that appears favourable at first can become a liquidity risk if retrospective settlement is delayed, volatile, or based on incomplete metering data. The regulatory outcome therefore depends on balancing over-collection against potential under-recovery that may surface later as a settlement adjustment.
RAAEY approach and role of network data quality
RAAEY is expected to retain the existing methodology while moderating the scale of DEDDIE’s proposed changes. The regulator’s decision reflects a trade-off between keeping coefficients high enough to avoid under-recovery and reducing them enough to limit overcharging for energy not lost in networks.
The quality of network data is described as central to the issue, with smart meters and more frequent settlement able to narrow the gap between estimated and actual electricity flows. Improved detection of non-technical losses can also affect outcomes, while without such improvements loss coefficients can function partly as an accounting mechanism for data uncertainty.
The source material distinguishes between technical and non-technical losses, stating that lower technical losses would reduce procurement volumes, carbon exposure and costs passed through to consumers. Non-technical losses, including unmetered consumption and theft, are said to require different measures involving enforcement and metering investment.
The proposed coefficients are described as providing modest immediate relief, with suppliers expected to assess the reform based on how stable later settlements prove to be. The €164 million adjustment from 2022 remains the benchmark for settlement risk referenced in discussions around the current revision process.
