Low tariff electricity
Low tariff electricity denotes various kinds reduced rate for electricity. In the household sector, a distinction must be made between day, night and heating electricity tariffs (see also variable tariffs ).
In order to use low tariff electricity, either a special electricity meter (see also intelligent electricity meter ) and a device for switching to normal or high tariff (HT) and low tariff (NT), which is achieved through so-called ripple control technology , or a separate electricity meter, which is also required is switched by the aforementioned ripple control technology. Separate electricity meters are necessary if, in addition to single-phase alternating voltage with a nominal voltage of 230 V, which is common in Europe , three-phase alternating current with 400 V, for example for an electric storage heater, is used.
The energy supply companies carry out the switchover via time switches or remotely using a frequency modulated onto the mains voltage or via long-wave radio in the form of radio ripple control technology . The signal is sent to the meters by the utility company at the switching times. However, so far the signal can only be sent over a limited spatial distance. Switching over several hundred kilometers has not yet been possible, which is why it is usually the local basic suppliers who deliver night or low-tariff electricity.
purpose
The purpose is to utilize the power plants, especially nuclear power plants , wind power plants and hydropower plants without storage facilities, better or as evenly as possible during the so-called low load phases through power plant management (see also intelligent power consumption ). This mainly applies to the night hours, which is why the term night power is also used colloquially .
Electric storage stoves
Capacities not used by other customers - night power - are then offered at a reduced price for the operation of electrical devices with normal voltage or at a reduced price for bulk buyers, such as night storage heaters . Household appliances such as dryers and washing machines are switched from high to low tariff and back using multi-tariff electricity meters . Three-phase electricity meters are also switched by a signal in the low tariff time window and the connected storage heaters are thus heated .
Electrically operated heat pumps
Furthermore, changes in the generation and distribution of electricity with ripple control technology can be absorbed by interventions on the consumer side - within certain limits. So z. B. a selective load shedding of less important network load in the event of a lack of power. This scenario is used, for example, in electrically operated heat pump heating systems . The power supply to the heat pump is both switched on and off by the ripple control signal .
At times when there is a high total energy demand from the power grid, for example in the morning and in the evening, heat pump heating systems can be switched off up to three times a day for two hours each (also remotely controlled) according to the technical connection conditions. Another name for this switch-off time is the blocking time .
criticism
Although the tariffs during the night are up to 30% below the regular working price, the electricity during the high tariff, i.e. during the day, is significantly more expensive than in conventional electricity tariffs. In addition, the periods for low and high tariffs are not uniformly regulated. Each provider defines this individually. Thus it can only be determined on the basis of exact calculations whether the choice of such a tariff actually brings savings.
See also
- Smart meters (Smart Meter)
Individual evidence
- ↑ Night power at Alinki
- ↑ Advantages and disadvantages of low tariff electricity. April 9, 2019, accessed July 25, 2019 .