Dynamic tariffs can reduce electricity costs, but in Romania, switching contracts does not guarantee savings

ACER estimates that dynamic tariffs and shifting consumption to cheaper hours could have reduced costs for many European households under 2025 market conditions. Simulations for Romania, however, show very different results depending on the type of household: simply switching to a dynamic contract can increase the modeled cost, while savings arise mainly when consumption can actually be shifted to cheaper hours.

Dynamic electricity tariffs can bring savings to households that can shift their consumption to periods with lower prices, but simply switching from a contract with a relatively stable price to one linked to market developments does not guarantee a lower bill. The new ACER and CEER report on retail markets explicitly separates two effects: changing the contract structure and changing consumption behavior. In Romania, simulations for 2025 show that the first effect is negative for all four household types analyzed, while shifting consumption to cheaper periods generates potential savings, especially for households with electric vehicles.

In brief
Only 7% of residential customers monitored by ACER in the EU and Norway had dynamic contracts in 2025, although approximately 66% had smart meters.

ACER separately models the effect of switching from a contract with a relatively stable average price to a dynamic one and the effect of shifting consumption to cheaper hours.

For a model household in Romania with annual consumption of 3,000 kWh, switching contracts produces a minus EUR 7 effect in the simulation, while consumption flexibility brings an estimated benefit of EUR 64.

For a household with an electric vehicle, the effect of switching contracts is minus EUR 98, but shifting charging and other flexible consumption to cheaper hours produces an estimated benefit of EUR 317.

The results are simulations, not promises of savings. They use 2025 prices and modeled consumption profiles and do not include all supplier fees, network tariffs, or other bill components.

Dynamic contracts link the price paid by consumers more directly to wholesale market developments, usually on an hourly basis. During periods of high generation and low demand, electricity may be cheaper, and consumers who can schedule an electric vehicle’s charging, the operation of certain appliances, or part of their heating during those periods can reduce the energy component of their costs. The same mechanism also works in reverse: if a household mainly consumes electricity when prices are high, more direct exposure to the market can increase costs.

The ACER and CEER report aims specifically to separate these two effects. The first, called the contract-structure effect, compares a dynamic contract with a reference price representing the average structure of existing contracts on the market. Consumption remains unchanged, so the result shows what would have happened if the household had changed only its contract. The second effect maintains exposure to dynamic prices but assumes that part of consumption can be shifted from expensive hours to cheaper periods.

ACER warns that the reference contract is not a specific commercial offer from a supplier. It is a benchmark constructed from market data to enable comparisons between countries, and the results should be interpreted as an indication of direction and magnitude, not as precise savings for a real household. Consumption profiles differ from one family to another, as do contract prices, fees, network tariffs, taxes, and the actual ability to shift consumption.

The modeling uses four household types. The basic household consumes 3,000 kWh per year. The heat-pump model reaches 6,000 kWh, the electric-vehicle model 6,500 kWh, and a household with both technologies 9,500 kWh. For the basic hourly profile, ACER uses consumption data from 2019 to avoid, as far as possible, the existing influence of heat pumps and electric vehicles, while the prices used for the results presented are those from 2025.

Romania offers a clear example of the difference between changing a contract and changing behavior. For the basic household, the simulation shows a contract effect of minus EUR 7, equivalent to approximately minus 1% of the annual reference bill, meaning that simply switching to the modeled dynamic contract would have been slightly more expensive. Shifting part of consumption to more advantageous hours, by contrast, produces estimated savings of EUR 64, approximately 11% under ACER’s methodology.

For the household with a heat pump, the difference is even more pronounced. The contract-structure change is modeled at minus EUR 133, approximately minus 11%, while consumption flexibility generates an estimated benefit of EUR 116, approximately 10%. The two components almost offset each other, but the result shows why having a heat pump does not automatically make a dynamic contract a cheaper choice. Thermal comfort also limits how much the system’s operation can be shifted from one hour to another.

The electric vehicle offers much greater flexibility. In the Romanian scenario, changing the contract has a modeled effect of minus EUR 98, approximately minus 8%, but changing consumption hours generates a benefit of EUR 317, approximately 24%. The difference stems from the possibility of scheduling charging during periods when energy is cheaper without the user giving up the final service: traveling by car.

For the household combining an electric vehicle and a heat pump, changing the contract has an effect of minus EUR 224, approximately minus 12%, while consumption flexibility produces a modeled benefit of EUR 369, approximately 19%. These two figures should not be presented separately from the report’s methodology or turned directly into a promise about the bill of a Romanian family. They describe two effects modeled under the same conditions, based on a standardized consumption profile.

At European level, ACER estimates that, under 2025 market conditions, households combining a dynamic contract with consumption shifting could have obtained significant benefits. For the basic household, the average presented by the agency is approximately EUR 120, while ACER’s communication also expresses the potential as approximately 20% in its comparison. For households with electric vehicles, the modeled value at European level is higher because a significant share of consumption can be shifted relatively easily between hours.

This European average cannot be applied directly to Romania, nor simply subtracted from the approximately EUR 840 that the report uses for average annual electricity expenditure at EU level. The flexibility calculation mainly concerns the energy and supply component, while the methodology excludes network tariffs and other non-energy components. Suppliers may also have administrative fees or costs associated with dynamic offers that are not fully included in the model.

The historical analysis also shows that the advantage is not permanent. During the energy crisis, particularly in 2022, direct exposure to wholesale prices could make dynamic contracts considerably more expensive in certain markets. The report thus shows that a dynamic contract transfers to consumers both the opportunity of low prices and a greater share of the risk of high-price periods.

ACER includes Romania among the markets of Central, Eastern, and Southeastern Europe where retail prices and market interventions may make simply switching from the existing contract structure to a dynamic price less advantageous than in Western Europe. In 2025, within this group, the modeled benefit came mainly from actually shifting consumption, not from changing the contract itself. The exact situation of commercial offers available in Romania, however, requires updated national data and cannot be inferred from this simulation alone.

Technical availability is another limitation. Approximately 66% of residential customers monitored by ACER in the EU and Norway had smart meters in 2025, but only approximately 7% had dynamic-price contracts. A smart meter enables consumption to be measured at intervals short enough for such products, but its installation does not guarantee that suppliers offer dynamic contracts, that prices are attractive, or that users can automate their consumption.

ACER believes that retail markets should offer consumers a genuine choice between price stability and exposure to market fluctuations. The agency does not recommend that all households switch to dynamic prices and stresses that not all consumers can frequently change when they use electricity. For those who cannot or do not wish to take on such exposure, fixed-price contracts continue to serve an important protective function against volatility.

For Romania, the main conclusion of the simulation is that flexibility matters at least as much as the type of contract. In all four scenarios, simply changing the contract structure has a negative effect under the conditions modeled for 2025, while shifting consumption generates a positive benefit. The advantage of a dynamic tariff therefore depends on what the household can do after changing the contract, not merely on the existence of a “dynamic” commercial label.

https://2eu.brussels/ro/explainer/tarifele-dinamice-pot-reduce-costurile-cu-electricitatea-dar-in-romania-schimbarea-contractului-nu-garanteaza-economii