Atypical grid usage occurs when an electricity consumer places comparatively little demand on the grid during its typical peak periods and reaches its own maximum demand outside these periods. The timing of electricity consumption is decisive, rather than low annual consumption alone.

Atypical grid usage at a glance

• The grid operator defines peak-load time windows during which the consumer’s demand must remain significantly below its annual maximum demand.
• An existing operational load profile may already qualify; flexible loads and battery storage can support implementation.
• Eligibility depends on regulatory requirements. Proposed changes from 2029 affect long-term financial planning.

How do peak-load time windows and charge calculations work?

The grid operator publishes peak-load time windows for each calendar year, differentiated by voltage or transformation level and season. The consumer’s connection level determines which windows apply.

The assessment compares the consumer’s highest grid import demand across all applicable peak-load time windows with its annual maximum demand. The billing-relevant 15-minute average power values form the basis of this comparison.

To calculate the individual network charge, the highest demand within the peak-load time windows is generally multiplied by the applicable demand rate. The energy-based network charge for the electricity consumed is added, and the minimum charge still applies.

An energy management system (EMS) can limit grid imports during these windows. It measures power at the grid connection point and, for example, postpones charging, reduces flexible loads or initiates battery discharge. The control system must respond promptly and account for the billing intervals.

Simplified example: A facility reaches 800 kW outside the peak-load time windows and no more than 500 kW within them. The difference is 300 kW, or 37.5%. This percentage describes the difference in demand, not the reduction in the total network charge. The individual demand charge is generally calculated using 500 kW. The remaining eligibility requirements must still be checked.

Which facilities can benefit?

Typical applications include:

• Facilities with a suitable production schedule: Their power-intensive processes already take place outside the published peak-load time windows.
• Sites with shiftable loads: EV charging, pumps or cooling systems can be rescheduled within operational constraints.
• Commercial and industrial sites with battery storage: The battery supplies part of the facility’s consumption during the time windows, reducing grid imports.

What requirements and limitations apply?

The significance threshold defines the required percentage difference between the two maximum demand values. It is, for example, 20% for a medium-voltage connection and 30% for a low-voltage connection. Additional requirements generally include a demand difference of at least 100 kW and a minimum annual network charge reduction of €500. The individual network charge must not fall below 20% of the published standard network charge.

An individual network charge agreement with the grid operator and a complete notification are required. For the Federal Network Agency, this notification must generally be received by 30 September of the year from which the agreement is intended to apply. This does not create an annual requirement to submit a new notification; reporting and evidence requirements remain. Where a state regulatory authority is responsible, its requirements must be followed. The eligibility conditions must actually be met.

Unlike general peak shaving, atypical grid usage focuses on limiting demand within defined time windows. A single high 15-minute demand value within these windows can reduce savings or jeopardise eligibility.

Battery discharge power, usable energy and state of charge must be sufficient for the required duration. Charging schedules, operational reserves and behaviour during communication failures must be defined in advance. The financial assessment must consider investment costs, storage losses and battery degradation alongside the network charge reduction.

Peak-load time windows are not electricity market price windows. Low electricity prices may occur precisely when additional grid imports should be avoided. The EMS therefore needs clear priorities between electricity procurement, network charge optimisation and operational requirements.

How does EcoPhi support atypical grid usage?

EcoPhi can record grid import data, analyse load profiles and support project-specific, time-dependent power limits through battery and load control. Peak-load time windows, measurement intervals, storage reserves and control priorities must be coordinated.

Implementation depends on device interfaces and available control capabilities; additional integration or engineering services may be required. Monitoring alone does not ensure compliance. The network charge agreement, notification and regulatory evidence remain separate responsibilities of the operator or its appointed service providers.

Atypical grid usage summarised

Atypical grid usage can reduce network charges where the load profile and regulatory conditions qualify. An EMS supports technical implementation. Available flexibility, implementation costs and the future regulatory framework determine whether the approach is financially worthwhile.

Frequently asked questions about atypical grid usage

Is battery storage mandatory?

No. An existing suitable load profile or the rescheduling of controllable loads may be sufficient.

Is a photovoltaic system enough?

Only if the remaining grid imports meet the requirements. Weather-dependent generation alone does not ensure reliable demand limitation throughout all relevant time windows.

Can grid imports increase without restriction outside the peak-load time windows?

No. Connection capacity, technical operating limits and other contractual requirements continue to apply.