Storage heating – Advice
Better to store energy than to give it away.
A new role for domestic storage heaters
Against the backdrop of the energy transition, storage heaters may gain a completely new relevance. Existing capacities, for example in pumped water hydro power stations, are inadequate for buffering the large fluctuations in the amount of power delivered by wind power and photovoltaic plants at peak times. This is where storage heaters can be utilised as thermal stores that will absorb available peak power from the grid.
More than 1 million residential units in Germany are still equipped with electric storage heaters. These offer more than 5 times the storage capacity of existing pumped water hydro power stations.
Modernisation - an investment for users and the environment
The change in the political and energy supply situation makes it worthwhile for building owners to replace their old storage heaters (which are, in some cases, more than 40 years old) with advanced and efficient storage heating systems. An investment that will pay off for users and the environment.
Experience shows that simply combining an electronic weather-compensated charger system with new storage heaters achieves energy savings of up to 20 % - compared with an older storage heating system without weather-compensated charge control. Advanced storage heaters with an electronic charge controller and significantly improved heat retention ensure that accurate temperature delivery can be achieved. Any residual heat is also recorded much more precisely, meaning that only the energy deficit is made up by additional charging.
- The expansion of renewables requires the creation and utilisation of storage options
- Insufficiently utilised storage options require the export of excess capacities
- In 2013, the excess that was exported amounted to 34.3 TWh
- However, theoretically storage options are available
- Existing storage potential in the shape of thermal stores
- Utilising this potential requires intelligent load management
- Excess capacities (balance) and storage potential are - looking at the year as a whole - largely the same
The energy transition is here
As wind and solar power generation fluctuates, the storage capacity of existing storage heater systems should also be used to specifically reduce grid surpluses.
If storage heater systems are used as part of load management, the power mix also shifts in favour of renewables and improves the life cycle assessment of night storage heaters. Today, advanced storage heaters for load management help to provide us with improved integration of the electricity generated by renewables.
Time load offset reduces the strain on consumers and the grid.
The important role of storage heaters for the energy transition has been recognised
EnEV 2014 [Germany] no longer requires older storage heating systems to be shut down, something which was stipulated in para. 10a of EnEV 2009. Existing systems can be operated beyond 2020, even if they are already more than 30 years old.
The initiative to revoke this regulation came directly from the German Federal Parliament. Politicians were responding to the continually rising proportion of environmentally responsible renewable energy sources in the power mix and the associated requirements for storage and utilisation.
Up to July 2013, according to para. 10a of EnEV 2009, the operation of storage heating systems was to be prohibited as of 1 January 2020 if they were installed prior to 1 January 1990 and the essential replacement measures could be demonstrated to be economical. It also stipulates that systems installed after 1 January 1990 should no longer be in operation after 30 years in use.
On 12 July 2013, the legislation amending the Energy Conservation Act was published in the Federal Law Gazette.
Para. 10a, pertaining to a qualified prohibition of electrical storage heating systems, was deleted without replacement.
According to the EnEV, there is no obligation to shut down old systems where systems/buildings have been modernised subject to economic viability, irrespective of whether the building comprises more or fewer than 5 residential units.
Reasons for the amendment
Today, we are faced with the problem of how best to store energy generated in a renewable and sustainable way, wind power for example. Electric room heating systems offer one option. This is why the German government decided to amend the legislation accordingly. Electric room heating systems are no longer required to be shut down as of 1 January 2020, but may continue to be
Benefits of the amendment
Electric room heating systems charge at night in off-peak periods and emit the heat the next day as required, assisted by integral room temperature controllers. Users benefit from lower night tariffs, because the power supply utilities' "night troughs" of demand can be filled by electric room heating systems with heat storage, and operation is more economical thanks to a constant output.