Which value stream is usually the biggest?

It depends on the tariff, not on the battery. Where there is a high charge per kW (many German sites), peak shaving often leads. Where the grid is full (much of the Netherlands), the connection limit decides. Where network charges are per kWh only (Romania), solar self-consumption and spreads are all there is.

Does a battery reduce my energy bill on its own?

Only through one of the four streams. Storing and releasing energy costs energy, so a battery with no peak, solar, price spread or limit to work on makes the bill slightly higher.

Can one battery do all four?

Yes, but not with the same kWh at the same moment. A study should show each stream separately, so you can see which one carries the case and which ones are a bonus.

Do I need a dynamic contract?

Only for arbitrage. Peak shaving, self-consumption and the connection limit work on any contract.

Peak shaving, self-consumption, arbitrage, connection limit: the four ways a business battery earns

1. Peak shaving: the charge per kW

Most commercial and industrial network tariffs charge for the highest 15-minute demand in a month or a year, per kW. A battery that discharges during those peaks lowers the maximum the meter records, and with it that charge. On Liander's 2026 tariff for medium-voltage connections of more than 136 up to 2,000 kW, the monthly kW max costs €3.57 per kW and the contracted capacity €2.29 per kW, per month (Liander 2026).

One kW held down in every month and taken off the contract is worth (2.29 + 3.57) × 12 = €70.32 a year on that Liander tariff.
In Germany the Leistungspreis is charged per kW of the year's single highest 15-minute load. On NEW Netz's 2026 medium-voltage sheet it is €118.34 per kW a year for sites above 2,500 full-load hours, and €16.80 below (NEW Netz 2026).
The catch: the battery has to hold the peak in every billing period. One missed afternoon sets the charge for the month in the Netherlands, and for the whole year in Germany.

2. Self-consumption: keeping your own solar

If the site exports solar at midday and imports in the evening, the battery stores the surplus and uses it later. Each kWh shifted is worth the import price minus the export price, less the losses on the way through the battery.

Illustrative: with an import price of €0.17/kWh and an export price of €0.05/kWh (both assumptions) and a round-trip efficiency of 90% (assumption), 1 kWh of surplus becomes 0.9 kWh used on site. It saves 0.9 × 0.17 = €0.153 of imports and gives up €0.05 of export revenue: €0.103 per kWh of surplus.
In the Netherlands, feed-in pays no transport charge on Liander's large-connection tariff (Liander 2026), so the export price is the supplier's feed-in price.
In Romania, self-consumed solar avoids the per-MWh network tariffs, which are energy-only (MET Romania notice of the ANRE tariffs from 1 Jan 2026), as well as the other per-MWh items on the bill.

3. Arbitrage: buying low, using high

On a contract that follows the day-ahead market, the battery charges in the cheap hours and discharges in the expensive ones. Between 1 July 2025 and 1 July 2026 the average 2-hour daily day-ahead spread was €118.12/MWh in the Netherlands, €121.16/MWh in Germany and €153.43/MWh in Romania (Synertics, updated 29 Jul 2026).

A cycle only pays when the high price times the round-trip efficiency is above the low price. At 90% round trip and a low price of €40/MWh, the high price must be above 40 ÷ 0.9 = €44.4/MWh before the cycle earns anything.
Market spreads are an upper bound: a battery does not know tomorrow's prices perfectly, and the energy it keeps back for peak shaving cannot be traded.
On a fixed single-rate contract there is no price difference to capture. Arbitrage needs a dynamic or time-of-use contract.

4. Connection limit: growing without a bigger grid connection

When the grid operator cannot raise the connection, a battery lets the site add EV chargers, a heat pump or a production line anyway: it charges while the site is below the limit and discharges when the new load would push it over. In the Netherlands this is the common case. At the end of June 2026 the regional grid operators' waiting lists held 15,498 requests for more offtake capacity, together 9,986 MW (Solar Magazine, 6 Oct 2026).

Real case: the De Walvis office building in Amsterdam installed a 320 kWh battery because its 137 kW connection could not carry peaks of about 200 kW (Solar Magazine, 27 Apr 2024).
Real case (vendor source): Albert Heijn's distribution centre in Zaandam uses more than 1.8 MWh / 800 kW of batteries to charge 70 electric trucks after its contracted capacity was reached (Intercel).
The value here is the growth the battery allows, or the grid upgrade it replaces, not the bill savings.

Stacking: one battery, several jobs

The same kWh cannot be in two places at once. Energy kept back for the afternoon peak is not available for arbitrage, and a battery full of morning solar has no room for cheap midday grid energy. A realistic controller sets priorities: hold the peak first, then store solar surplus, then trade with what is left. That is how Zorowatt's rule-based dispatch works, and every saving it reports is billed by the same bill engine as the baseline.

Where each value stream is strongest

Germany: the charge per kW is high for sites above 2,500 full-load hours (€118.34/kW a year at NEW Netz medium voltage). One vendor's brochure uses €13.61 and €12.38 per kW per month in its examples (EWS, 10/2025); those are one vendor's example values, not a German average.
Netherlands: the kW charges are lower (the €70.32 per kW a year above), so Dutch cases usually rest on the connection limit, often with peak shaving and arbitrage on top.
Romania: all regulated network tariffs are charged per MWh, with no kW component (MET notice). The value comes from solar self-consumption and spreads, which were the highest of the three countries in the period above.

What a battery does not do

It does not lower the site's consumption. It adds losses: at 90% round trip, every 100 kWh discharged needs about 100 ÷ 0.9 = 111 kWh charged.
It does little against long, flat peaks: the energy it needs grows with every hour the peak lasts.
It does not fix a wrong tariff or a wrong reading of the meter data. Those have to be right before any saving means anything.

To see what a peak cut is worth for one site, try the free peak-shaving calculator with four numbers or your own load profile. The Workspace runs all four value streams through a year of 15-minute data under the site's real tariff. Your first site analysis is free.

Frequently asked questions

Which value stream is usually the biggest?: It depends on the tariff, not on the battery. Where there is a high charge per kW (many German sites), peak shaving often leads. Where the grid is full (much of the Netherlands), the connection limit decides. Where network charges are per kWh only (Romania), solar self-consumption and spreads are all there is.
Does a battery reduce my energy bill on its own?: Only through one of the four streams. Storing and releasing energy costs energy, so a battery with no peak, solar, price spread or limit to work on makes the bill slightly higher.
Can one battery do all four?: Yes, but not with the same kWh at the same moment. A study should show each stream separately, so you can see which one carries the case and which ones are a bonus.
Do I need a dynamic contract?: Only for arbitrage. Peak shaving, self-consumption and the connection limit work on any contract.

Related guides

Sources

Last checked: 2026-10-30. Every figure in this guide comes from the source linked next to it, with the retrieval date Zorowatt's research recorded (28–30 October 2026), or from arithmetic shown step by step.

Stuck on something else? Ask the community.

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