Green Storage Index

Monthly revenue benchmarks for EEG-compliant storage with charging restricted to co-located generation — 2h and 4h assets, 4 to 10 MW. Two scenarios: wholesale markets (day-ahead + intraday) and full stack including ancillary services (FCR, aFRR).

50.4 EUR/MWh

PV Only · Annual revenue 2025

92 – 159 EUR/MWh

BESS Wholesale · DA + ID · Range

126 – 266 EUR/MWh

BESS DA + ID + aFRR · Range

+82% – +215%

Wholesale uplift vs. PV Only · Range

BESS Duration

BESS Power10 MWp PV

Markets

138.1 EUR/MWh

Wholesale

Ancillary Uplift

PV Only

EUR / MWh

Jahreserlös138.1 EUR/MWh·2h · 10MW · Jan – Dec 2025

Annual Revenues 2025 — Overview

Configuration	Wholesale Only	+ Ancillary	Ancillary Uplift	vs. PV Only
PV Only	50,37429.806 EUR	—	—	Basis
2h · 4 MW	91,79783.284 EUR	125,711.072.704 EUR	+37%	+82%
4h · 4 MW	112,06956.241 EUR	146,741.252.187 EUR	+31%	+122%
2h · 6 MW	109,34933.048 EUR	163,051.391.381 EUR	+49%	+117%
4h · 6 MW	133,931.142.890 EUR	190,791.628.027 EUR	+42%	+166%
2h · 8 MW	124,751.064.531 EUR	198,721.695.757 EUR	+59%	+148%
4h · 8 MW	148,931.270.889 EUR	231,061.971.665 EUR	+55%	+196%
2h · 10 MW	138,071.178.194 EUR	229,591.959.180 EUR	+66%	+174%
4h · 10 MW	158,891.355.862 EUR	266,352.272.805 EUR	+68%	+215%

Annual revenue per configuration in EUR/MWh — relative to annual PV generation. Jan–Dec 2025.

PV Generation 2025 — 10 MWp Reference Asset

8.533,211 MWh total

Model Assumptions

Period

January – December 2025 (12 months)

Configurations

2h and 4h storage, 4 MW / 6 MW / 10 MW each

Asset type

Green storage (EEG §19) — charging exclusively from co-located renewable generation

Wholesale Only

Day-ahead arbitrage + intraday arbitrage

Wholesale + Ancillary

Additionally FCR (Frequency Containment Reserve) and aFRR (Automatic Frequency Restoration)

Grid fees

Not deducted — gross revenues before grid fees and AgNes surcharge

Model

Catalyst dispatch optimiser (phelas)

Data sources

EEX/EPEX Spot, regelleistung.net

Comparison

BESS Revenue Index

Revenues for standalone storage without charging restrictions — for comparison with green storage revenues.

Read

Analysis

FCA & Grid-Fee Impact

How regulatory constraints affect the revenue stack — relevant for green storage projects.

Read

Note: All analyses and figures are based on simplified model assumptions and historical market data. They are for illustrative purposes and do not constitute investment advice. Project-specific analyses account for individual site parameters, current market prices, and financing structures.

Change 05.08.2026: Adapted generation curve for the year 2025. Only the total revenue per configuration was adjusted. Relative values remain untouched.

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