In brief
- Additional losses on the 110 kV network are no longer divided once a year between generators and the transmission system operator, but for every 15-minute settlement interval, with the results added up at the end. A year has 35,040 such intervals, so a single allocation operation becomes up to 35,040. The order amends letter (i) of Article 352 of the technical standard and adds a new letter (j), for the annual summation.
- The difference has consequences in money, because the sum allocated to generators feeds into the distribution tariff. Under the old rule, each party’s share was set in proportion to the energy fed in over the whole year, whatever the moments at which the losses arose. Under the new rule, what counts is who was feeding energy in during precisely those quarter-hours in which the 110 kV network was carrying transit above the reference regime.
- The order does not say from when the new calculation applies. It enters into force on 24 September 2026, that is, after 266 days of 2026, 72.9% of the year, have run under the old rule. The calculation, however, is made by calendar year, and no text shows whether 2026 is to be calculated entirely by the new method, entirely by the old one, or split in two.
Published: Official Gazette of Romania (Monitorul Oficial), Part I, no. 816 of 24 September 2026
In force from: 24 September 2026, the date of publication
From 24 September 2026, electricity distribution operators divide the additional losses on the 110 kV network differently between the generators connected to it and the transmission system operator. The order has two points and takes up less than a page, but it changes the very step of the calculation at which it is decided who pays: instead of a single annual allocation there is now an allocation for every 15-minute settlement interval, followed by a summation. It is the second act of the same regulator in two days to alter how the distribution tariff is built up, after the one under which energy communities can ask for a reduction in the distribution tariff.
The mechanism concerned is called the transit index method and was introduced into the technical standard by Order of the President of the National Energy Regulatory Authority no. 82/2023, published in Official Gazette of Romania, Part I, no. 721 of 4 August 2023 and applicable from 15 August 2023. Its idea is simple: part of the energy that runs through a distribution operator’s 110 kV network is merely in transit, instead of covering consumption in its licence area. That part is called additional transit, and the losses it produces are called additional technological own consumption, that is, the technical losses of the network itself. They fall on those who cause them, namely the generators connected to the 110 kV network and the transmission system operator.
To separate useful transit from additional transit, the standard divides the year into 15-minute settlement intervals and calculates a transit index for each of them. The intervals with additional transit below 10% of useful transit and those between 10% and 20% form, by convention, the reference regime. On those a linear regression function is built describing how technological own consumption depends on useful transit, and then, for the intervals outside the reference regime, what the normal loss would have been is calculated and subtracted from the loss measured. The positive difference is the additional technological own consumption; negative values are treated as zero.
Until now, the last step was performed only once. Letter (i) of Article 352 required the calculation of the total annual additional consumption and its allocation to „producătorilor și OTS, proporțional cu cantitatea de energie injectată anual în rețeaua de 110 kV”, to the generators and the transmission system operator, in proportion to the quantity of energy fed annually into the 110 kV network. In other words, everything produced by the previous steps was added up, a single figure for the year was obtained and it was divided according to the annual feed-in shares.
The new letter (i) requires the allocation formulas to be applied „pentru fiecare interval de decontare aflat în afara domeniilor de tranzit care definesc regimul de referință”, for every settlement interval outside the transit ranges that define the reference regime, and letter (j), added now, requires the values obtained over the intervals to be summed in order to arrive at the annual total and at the values allocated to the generators and the transmission system operator. The order has been reversed: first divide, then add.
What it changes in practice
The first effect is a shift of cost between the parties. Under the annual rule, a generator feeding a great deal into the network in the months when it was not carrying additional transit still bore a share proportionate to its feed-in over the whole year. Under the new rule, it bears only what corresponds to the quarter-hours in which additional losses actually arose. The winners are therefore those who generate steadily and outside transit peaks, and the losers those who generate precisely when the 110 kV network is carrying transit above the reference regime. For wind and solar power, where output is concentrated in certain hours, the difference is not theoretical.
The second effect is the volume of calculation. A calendar year has 35,040 settlement intervals of 15 minutes. The distribution operator now has to apply the two allocation formulas to every interval outside the reference regime, not once a year, and for each such interval it needs the quantities of energy fed in by the generators and by the transmission system operator in that very quarter-hour. These are metering data that exist, because market settlement uses the same time step, but going from one operation to several thousand changes the nature of the check.
The third effect concerns validation. Under Article 38 of the standard, the distribution operator sends the transmission system operator the calculation of the additional technological own consumption, if the result is greater than zero, and the transmission system operator validates it within 30 days, with any disagreements sent to the regulatory authority. The data are accompanied by the list of generators with installed capacity above 5 MW connected to the distribution network and by the quantities fed in by each power plant in the previous year. A calculation made over 15-minute intervals is far harder to validate in 30 days than one made on annual aggregates, and the deadline has not been changed.
The fourth effect can be seen in the distribution tariff. The methodology approved by Order of the President of the National Energy Regulatory Authority no. 169/2018 provides, in Articles 951 and 952, that the distribution operator asks the authority to approve the forecast quantity of additional technological own consumption for the following year, by 1 July each year, and to approve the quantity actually recorded for the previous year, in both cases broken down into the shares assigned to the generators and to the transmission system operator. The difference between forecast and outturn produces an annual correction. The change in the method of breakdown therefore feeds directly into that correction mechanism.
The fifth effect concerns an asymmetry kept in the standard. Letter (h) of Article 352 remains untouched: for intervals where the difference comes out negative, the additional consumption is treated as zero. In an annual calculation, negative intervals cancelled out in the aggregate anyway. In a calculation by interval, they are cut to zero individually, and the final sum is at least as large as before. Moving the allocation step onto the interval changes who pays and, through that asymmetry, how much is paid in total.
What has changed compared with the previous situation
The previous wording of letter (i), in force since 15 August 2023, read: „se calculează CPT suplimentar total anual utilizând rezultatele obținute din parcurgerea etapelor prevăzute la lit. g) și h) și se alocă producătorilor și OTS, proporțional cu cantitatea de energie injectată anual în rețeaua de 110 kV, prin utilizarea formulelor (55) și (56)”, that is, the total annual additional technological own consumption is calculated using the results of the steps under letters (g) and (h) and is allocated to the generators and the transmission system operator, in proportion to the quantity of energy fed annually into the 110 kV network, by applying formulas (55) and (56). It contained, in a single sentence, both the annual summation and the allocation, and it expressly indicated the basis of the allocation: the energy fed in annually.
The new wording of letter (i) keeps only the allocation, moves it onto each settlement interval outside the reference regime and removes the word „anual”, annually. The summation moves into the new letter (j), which produces both the annual total and the values allocated to each party, starting from the results under letter (i).
The real change is not one of drafting, but of arithmetic. Formula (55) divides the additional consumption between the generators and the transmission system operator according to the ratio between the energy fed in by the generators and the sum of the energy fed in by the generators and by the transmission system operator. If that ratio is calculated over the year, then it is the same for all intervals, and applying it to each interval followed by a summation gives exactly the previous result. If the ratio is calculated per interval, the result is different. The whole difference between the old and the new rule therefore lies in the period over which the energy fed in is measured, and the order does not state it.
What has not changed is the rest of the chain. Formulas (55) and (56) remain those of 2023, the definitions of the terms in Article 351 remain untouched, the ranges that define the reference regime remain D(0) and D(1), with the possibility for the distribution operator to change their number after informing the transmission system operator and the authority, and the 30-day validation deadline stays the same. The distribution tariff-setting methodology is not touched by this order.
Advantages and disadvantages
What it improves
- It ties the cost to the moment at which it arises. Additional losses are allocated according to who was feeding energy in during precisely the quarter-hours in which the network was carrying transit above the reference regime, not according to an annual average.
- It removes a dilution effect. A generator that does not contribute to additional transit no longer bears a share of it merely because it fed in a great deal over the rest of the year.
- It brings the allocation step onto the same time interval as settlement on the energy market, 15 minutes, so the data needed already exist in the metering.
- It separates the two operations into two distinct letters, (i) and (j), which makes the standard easier to read than the single sentence it had before.
- It does not touch the formulas, the definitions or the ranges of the reference regime, so it does not force operators to rebuild the whole calculation model.
What remains a problem
- The order does not say over what period the energy fed in is to be measured in the allocation formula. If it stays annual, the new rule gives exactly the old result and the change has no effect; if it is measured per interval, the result differs.
- There is no transitional provision, and the act enters into force on 24 September 2026, after 266 days of the calculation year. Operators cannot learn from the text which method to apply for 2026.
- The validation deadline for the transmission system operator stays at 30 days, although the object of validation goes from an annual figure to thousands of calculations by interval.
- The asymmetry in letter (h), which cuts negative values to zero, becomes more important per interval than in an annual aggregate and may increase the total allocated, without the order discussing that effect.
- The act provides for no obligation to publish the results by interval, neither to the generators nor to the public, although the generators bear part of the cost.
- The order does not align the amendment with Articles 951 and 952 of the tariff-setting methodology, where the forecast quantity is determined as the average of at least three previous years, calculated under the old method.
Practical advice
- If you are a generator with a power plant above 5 MW connected to a 110 kV distribution network, ask the distribution operator which allocation basis it will use: the energy fed in annually or the energy fed in during each settlement interval. The answer decides how much you pay.
- Compare your own feed-in profile with the hours in which the network in your area carries additional transit. Output concentrated in those same hours increases your share under the new rule, while baseload output reduces it.
- Distribution operators should ask the regulatory authority in writing for a clarification for 2026, before building the calculation. The order has no transitional provision, and a method applied wrongly is corrected only at validation by the transmission system operator.
- Prepare your interval data series in good time, not just the annual aggregates. The calculation calls for the quantities fed in by the generators and by the transmission system operator for every quarter-hour outside the reference regime.
- The transmission system operator should size its checks to the 30-day deadline in Article 38(3). The deadline has not been extended, and the object of validation has grown several thousandfold.
- Check how many transit ranges define the reference regime in your area. The standard allows the distribution operator to change their number, with justification, and that number determines how many intervals enter the allocation calculation.
- If you follow the distribution tariff, bear in mind that the change reaches it with a delay. The outturn quantity is approved for the previous year, and the forecast quantity is determined as the average of a period of at least three years, so the effect is seen spread out over time.
Frequently asked questions
What is additional technological own consumption?
Who pays for it?
What exactly has changed?
How often is the calculation made?
Does the new method apply to 2026 as well?
What happens to intervals where the calculation gives negative values?
Do generators have to do anything now?
From when does the order produce effects?
Errors and inconsistencies in the published text
- The new letter (i), as against the definitions in Article 351(2). The new text requires formulas (55) and (56) to be applied to each settlement interval, but does not say over what period the two quantities of energy fed in that enter formula (55) are to be measured, and their definitions in Article 351 contain no indication of a period. The word „anual”, annually, present in the previous wording of letter (i), was removed without being replaced. If the ratio is calculated over the year, it is constant across all intervals, and the summation required by letter (j) reproduces exactly the result of the old rule, so the amendment achieves nothing. If it is calculated per interval, the result is different. An operator acting in good faith may choose either of the two readings, and they give different allocations between the generators and the transmission system operator, with an effect on the distribution tariff.
- The absence of a transitional provision, as against the annual character of the calculation. The order enters into force on 24 September 2026, and additional technological own consumption is determined by calendar year, under Article 351(1). For 2026, 266 days have run under the previous rule and 99 under the new one. The act does not show whether 2026 is to be calculated entirely by the new method, entirely by the old one, or split over the two intervals, and the three variants produce three different allocations, which feed into the outturn quantity approved under Article 952 of the distribution tariff-setting methodology.
Editorial analysis
The order has two points and changes the order of two mathematical operations. That is exactly why it deserves reading with a pencil: in an act of technical regulation, the order of operations is itself the rule of law. Here it decides how much of the 110 kV network’s losses a generator bears, and from there the sum reaches the distribution bill, through the tariff-setting methodology.
The first observation becomes visible only when the order is set beside the wording it replaces. The 2023 text said that the allocation is made „proporțional cu cantitatea de energie injectată anual în rețeaua de 110 kV”, in proportion to the quantity of energy fed annually into the 110 kV network. The new text says nothing about a period. The definitions of the two quantities in Article 351(2) have not been touched and they too indicate no period. The result is a rule that calls for a calculation by interval, but does not state whether the input data for that calculation are per interval or annual. This is not a subtlety: if they remain annual, the allocation weight is identical across all intervals, and the sum required by letter (j) faithfully reproduces the old result. In other words, on one of the two possible readings, the order changes no figure at all.
The second observation concerns an effect the act does not mention, although it follows directly from the structure of the calculation. Letter (h) requires negative values to be treated as zero. In an aggregate calculation, a negative deviation on one interval reduces the total; in a calculation by interval, it is cut to zero and no longer offsets anything. Moving the allocation onto the interval does not stop at redistributing the same sum: it may increase the total allocated. The explanatory memorandum to such an order should have quantified the effect, and the standard should have said in what order the zero rule and the summation rule apply.
The third observation concerns the proportion between the change and the capacity to check it. Article 38(3) gives the transmission system operator 30 days to validate the results received from the distribution operator. The object of validation was, until now, an annual total and a share. From 24 September 2026 it may cover up to 35,040 allocations by interval, each with its own input data. The deadline has stayed the same. A procedural deadline that does not move when its object grows several thousandfold protects nobody: it produces formal validations or disagreements referred to the regulatory authority.
The fourth observation concerns the calendar and who pays for the delay. The transit index method has been working since 15 August 2023, and the first outturn quantity was approved, under Article 952 of the tariff-setting methodology, from 2025, for 2024. So the method has already been applied for two full years, 2024 and 2025, and the correction for 2026 will be calculated in 2027. The amendment comes 3 years and 40 days after the method entered into force, three months and seven days before the end of the calculation year, and with not a word about transition. The forecast quantity, in turn, is determined as the average of at least three previous years, years calculated under the old rule. For several years, therefore, the distribution tariff will contain a forecast built on one method and an outturn built on another.
Finally, an observation about what is visible from outside. Generators bear part of the cost of the additional losses, and their share is now set by quarter-hour, from data held by the distribution operator. The standard provides for the list of generators with installed capacity above 5 MW and the quantities fed in by each to be sent, but to the transmission system operator and to the regulatory authority, not to the generators themselves. A generator has, under the standard, no express right to see how its share was arrived at, although the basis of the calculation has just become several thousand times more granular.
What should be changed
- Letter (i) should say expressly that the energy fed in is taken for each settlement interval. Five extra words would close the only real ambiguity in the order and would show that the amendment does produce a result different from the previous one.
- The order should be supplemented with a transitional provision for 2026. A sentence saying that the new method applies from calculation year 2027, or that 2026 is calculated entirely by the new method, would spare operators and the authority a round of disagreements at validation.
- The validation deadline in Article 38(3) should be aligned with the new volume of calculation. If the object of validation goes from one figure to thousands of allocations by interval, the 30 days must be either extended or accompanied by a standard reporting format making the check capable of automation.
- The zero rule in letter (h) should be reworded together with the new order of operations. The standard should say whether negative values are cancelled per interval, before the allocation, or offset in the aggregate, because that choice determines the total charged to the generators and the transmission system operator.
- Generators should receive, on request, the calculation of their own share. A paragraph in Article 38 requiring the distribution operator to communicate to each generator the basis on which its share was calculated would make the mechanism contestable in fact, not merely in principle.
- The forecast under Article 951 of the tariff-setting methodology should be adjusted for the years calculated under the old method. Otherwise the average over at least three years mixes results obtained by two different methods, and the annual correction will reflect the change of method rather than the real movement in losses.
Original text of the legal act
The text below is reproduced in Romanian, the official form of publication.
The full text, as published in the Official Gazette of Romania
Official Gazette of Romania no. 816 of 24 September 2026 8 pages PDF, 77 KB the act starts on page 8
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This article is for informational purposes only and does not constitute legal advice. For specific situations, consult a licensed attorney or tax advisor.