Battery storage revenues: BTM reduces costs, FTM generates revenue
Most providers sell hardware or electricity. CUBE CONCEPTS builds the system behind it.
Two sources of income – most people see only one
- ✓Peak Shaving – reducing the performance prize
- ✓§19, paragraph 2, sentence 1 – Net cost reduction (until 2028)
- ✓§118, paragraph 6 – 20 years exemption for electricity fed back
- ✓Maximize PV self-consumption
- →FCR – Primary control output
- →aFRR – Secondary regulatory performance
- →mFRR – Minute reserve as an additional channel
- →Spotarbitrage – fully automated
No either/or – Multi-Use combines both revenue sources simultaneously.
Five factors determine your business case
This is relevant for you if you have a ≥ 500 kW grid connection (BTM) or can offer a regulated power output of ≥ 1 MW (smaller systems in a pool) – and want to understand the full revenue mix before making a decision.
Grid connection
BTM: from 500 kW. Regulated energy: Minimum offer of 1 MW, smaller systems included in the pool. Multiple locations can be bundled together.
C-rate
2h systems (0.5C) achieved around €259,000/MW in 2025, 1h systems around €151,000/MW (ISEA). For FCR, the regulatory authorities require a minimum activation time of 15 minutes and a 25% % power reserve, not a specific C rate. Incorrect design = no potential for profit increase.
Network operator
Grid fees, peak load periods, and connection conditions differ depending on the network operator; regulated energy prices apply uniformly nationwide. CUBE analyzes your network connection based on the specific requirements of the network operator.
Regulations
§118: 20 years exemption, according to the AgNes draft only for the investment decision before January 1, 2027, commissioning by August 4, 2029. §19 expires at the end of 2028. Those who plan too late will pay permanently more.
BTM/FTM-Split
The revenue mix is determined by how much capacity remains available for FTM marketing after BTM coverage (peak shaving, §19).
1 MW industrial storage in multi-use operation – in concrete terms
Basis: 1,000 kW / 2,000 kWh LFP system. Calculation example CUBE CONCEPTS with 220,000 € gross revenue, in the lower range of 200,000–300,000 €.
| Position | Amount / Year |
|---|---|
| FTM Gross Revenue / Year (FCR + aFRR + mFRR + Spot Arbitrage) | 220.000 € |
| OPEX / Year (Operations, Marketing, IT) | -55,000 EUR |
| Net Market Revenue / Year | 165.000 € |
| Contracting – 0 € CAPEX, Off-Balance | |
| Profit-Share Owners 25 % (based on net market proceeds after OPEX) | €41,250 / year |
| Profit Share CUBE CONCEPTS 75 % (Open-Book) | 123,750 € / year |
| Purchase – GIK ~ 250 €/kWh, 100 % own revenues | |
| All net market proceeds to the owner | €165,000 / year |
Source: Computational example by CUBE CONCEPTS; Reference IRR from KPMG comparison calculation (10 MW / 40 MWh, Feb. 2026) · All information provided without guarantee · Site-specific calculation based on your load profile.
What battery technology – and why LFP?
LCOS (Levelized Cost of Storage) is the right measure – not the purchase price. It takes into account investment costs, lifetime, degradation, and efficiency.
| Parameter | LFP | Zinc bromide | New in box |
|---|---|---|---|
| LCOS (€/MWh) | 110 | 104 | 127 |
| Degradation / Year | 2,1 % | 0,3 % | 3,0 % |
| Service life | 14 years | 25 years | 10 years |
| AC-AC efficiency | 87 % | 81 % | 85 % |
LFP: highest IRR of the KPMG comparison calculation (10.5 %) and fast amortization; ZnBr has the lowest LCOS.
* NIB = Sodium-ion battery (Na-ion). Basis: 10 MW / 40 MWh / WACC 6 % / 2 VZ/day. Source: KPMG AG, February 2026, p. 15–21.
What comes when – and what does that mean for your decision?
MiSpeL: PV + FTM compatible
BNetzA determination: PV system can simultaneously generate FTM revenues without losing EEG subsidies; until 30.09.2027, in agreement with network and metering station operators.
§118: Due date for investment decision (draft)
According to the AgNes planning draft, new storage facilities will receive the 20-year exemption only upon final investment decision before the announcement of the determination, planned for January 1, 2027.
Section 19, paragraph 2, sentence 1 of StromNEV expires
Atypical network usage – last application deadline is September 30, 2028.
AgNes: new network tariff system
According to the draft of 06.08.2026: Capacity price based on the ordered capacity, with a reference to a 2- to 3.5-fold cost of work; no follow-up for atypical network usage (BNetzA, GBK-25-01-1#3).
§118: Last day of commissioning
20 years of exemption from the network fee for electricity consumption, insofar as it is fed back into the grid. Legally limited in duration; not retroactively applicable. Existing connection: 6–12 months planning lead time.
Unused gross market revenue: approximately €17,000–25,000 per month at 1 MW (CUBE CONCEPTS guideline) · Source: §118 Paragraph 6 of the Energy Industry Act
Contracting or purchase – which is more economical?
Both models have access to the same revenue streams. The difference lies in capital investment and revenue sharing.
Contracting
- ✓ 0 € CAPEX – no own investment
- ✓ Off-balance sheet possible (accounting to be checked for each contract structure)
- ✓ 25 % Profit Share of Net Market Revenues after OPEX
- ✓ CUBE CONCEPTS operates and markets completely
- ✓ Call option contractually anchored
Purchase
- → Full self-investment (GIK ~ €250/kWh)
- → On-Balance – Activation and depreciation
- → 100 % of net market proceeds to the owner
- → Reference IRR 10.5 % (KPMG comparison calculation LFP, 10 MW)
- → Optional: CUBE CONCEPTS Takes Over Operations
“Our open-book calculation is not a bargaining position – it is the foundation on which partnership works.”
3 scenarios: Basic / Conservative / Optimistic – all open before your decision is made.
Manufacturer-independent Mind. 3 offers · LCOS-rated · no vendor lock-in. Both models.
What perspective applies to you?
Four areas of responsibility – each with a different perspective on the same business case.
You are responsible for investment decisions & balance sheet clarity
Reference IRR 10.5 % (KPMG, LFP 10 MW), available off-balance sheet (tested according to each contract structure), CAPEX relief through Contracting – or full control during purchase. Open book before your decision.
You are responsible for sustainability goals and CSRD reporting
Lower grid connection due to self-consumption of PV reduces Scope 2 emissions. Industrial electricity price eligible for investment in energy storage (CISAF, items 121–122). Auditable ESRS-E1 data points by default.
You are responsible for operational safety & plant engineering
FTM operation runs fully automatically – no interference with the operating processes. BTM dispatch coordinates CUBE EfficiencyUnit, not you.
You are responsible for energy procurement and electricity purchase costs
Peak shaving lowers the demand charge. Sections 19 and 118 reduce grid fees. FTM generates active revenue. All from one plant.
Common objections – direct answers
Tier-1 industrial companies – energy projects implemented across Europe
Over 150 realized PV projects, multi-site deployments across Europe. Now battery storage – on the same foundation, with the same ambition.
Energy projects Europe-wide
Frequently Asked Questions about Battery Storage Returns and Profitability
Submit your load profile – free potential analysis
Your lead generation is the foundation. We calculate based on the specific location – no portfolio benchmarks, no blanket statements.
Submit load profile
(15-minute data, 12 months)
Analysis
(5 business days)
Open-book accounting
– Your decision
§118: Investment decision according to the AgNes draft before January 1, 2027 · yet 83 Days
Next Steps & Related Topics
Battery storage systems reduce energy costs. Actuate regulators to make them a lever. Activate the revenue potential at your power grid connection – today.
BTM revenue in detail – performance award, §19, §118.
Learn More →FCR, aFRR, mFRR, Spotarbitrage – FTM channels in detail.
Learn More →BTM + FTM simultaneously – maximum profit mix.
Learn More →CUBE Profit Flex Solution – Three-phase model as Contracting (0 € CAPEX) or purchase.
Learn More →