Peak shaving: what is it and how does a battery help reduce peak consumption?

The electricity grid is under increasing pressure. Heat pumps, electric cars, charging stations, and solar panels are causing significant peaks in power consumption. These peaks are overloading the grid and increasing costs for households and businesses.

The solution? Peak shaving —a smart technology that smooths peak consumption by storing or releasing energy at the right times. In this blog post, we explain what peak shaving is, why it's becoming increasingly important, and how a home battery can help.

What is peak shaving?

Peak shaving literally means "shaving off peaks" in your electricity consumption. During periods of high simultaneous consumption (e.g., cooking, heat pump + washing machine + EV charger), a consumption peak occurs.

Peak shaving ensures that you flatten these peaks by:

  • not to take extra power from the grid, but
  • to use from your home battery

The result:

  • less load on the grid
  • lower costs
  • better efficiency
  • less risk of fuses tripping

Why do peak loads occur?

Households are becoming increasingly "electric." Consider:

  • heat pumps
  • induction hobs
  • charging stations
  • air conditioners
  • boilers
  • washing machines and dryers

When multiple heavy appliances are running simultaneously, your power consumption can reach 8 kW, 10 kW, or even more. This can lead to:

  • higher costs (with peak power contracts)
  • problems due to grid congestion
  • overload of the meter box
  • restrictions on EV charging

Peak shaving prevents these temporary peaks from becoming too high.

How does peak shaving work with a home battery?

A home battery can supply power directly to your home during peak times, meaning you don't need to draw any or less power from the grid.

1. The battery monitors your real-time consumption (via the EMS)

The EMS sees exactly:

  • how much electricity you use
  • which devices are active
  • what the maximum grid load is

2. Once you exceed a set limit

For example: maximum grid consumption 4 kW. The EMS automatically starts supplying power from the battery.

3. The battery provides the extra power

If you use 8 kW, you can set the battery to:

  • 4 kW delivers
  • 4 kW comes from the grid

4. Your total consumption peak is flattened

The grid only "sees" what you're still using. This keeps peak loads and costs low.

Example of peak shaving in practice

Situation:

  • heat pump (2.5 kW)
  • induction hob (3 kW)
  • EV charger (3.7 kW)

Total: 9.2 kW peak load
Maximum permitted grid power: 6 kW

With a home battery of 5 kW capacity:

  • 6 kW from the grid
  • 3 kW via the battery

You stay neatly within the limits — no downtime, no overload and no extra costs.

What are the benefits of peak shaving?

  • Lower energy costs (with peak consumption contracts)
  • Protection of the main fuse
  • Better balance in the meter cupboard
  • Higher self-consumption
  • Essential for phasing out netting
  • Important in case of grid congestion

Peak shaving only works optimally with an EMS

An EMS determines:

  • when the battery needs to jump in
  • how much power needs to be supplied
  • which devices have priority
  • how peaks are distributed throughout the day

Without EMS you would never be able to arrange this manually.

How much power do you need for effective peak shaving?

The required battery capacity depends on the peak load you want to smooth. Guidelines:

  • 5 kW → suitable for families with a heat pump
  • 7 kW → ideal for EV charging + heat pump
  • 10 kW or more → perfect for all-electric homes

NB:
Capacity (kWh) determines how long a battery can handle peak loads.
Power (kW) determines how much peak power you can smooth out.

Peak shaving for companies

Peak shaving began primarily in the business market, where energy suppliers charge for peak power. A battery can save thousands of euros per year there.

But thanks to heat pumps, fast chargers, solar panels and dynamic energy contracts, peak shaving is now also becoming important for private individuals.

Conclusion: Peak shaving is a smart way to reduce peak consumption and save costs.

Peak shaving provides:

  • lower peak loads
  • lower energy costs
  • less risk of overload
  • better integration of heat pumps and solar panels
  • optimal use of your home battery
  • a more stable home installation

With a home battery and EMS, you can intelligently smooth your consumption peaks and fully prepare your home for an all-electric future.

Want to know which home battery is best for peak shaving? Check out the solutions at aboutwatt.com .

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