Get more out of your wind or solar farm—with a storage system connected to your existing grid connection.
Co-location
One Grid Connection, Two Systems—A Brief Explanation
In a co-location arrangement, a battery storage system and a wind or solar farm share the same grid connection point. Both remain legally and technically independent facilities—the storage system does not become part of the farm, but rather shares its grid infrastructure.
Your Challenge – Our Solution
Problem
Revenue Under Pressure
As of February 25, 2025, new wind and solar power plants will no longer receive compensation during hours when electricity prices are negative.
Solution
Postpone Feed-in
The storage system shifts power delivery to hours when prices are higher and generates additional revenue from balancing power and electricity trading.
Problem
Curtailment Reduces Yield
When wind or solar power generation is high, the plant is throttled back or shut down.
Solution
Save Surplus
The storage system stores excess electricity and feeds it back into the grid at a later time.
Problem
Power is in short supply
New connection capacity is often not available for years.
Solution
Use an existing connection
The storage system uses your park’s existing grid connection and increases its utilization.
Your Benefits
Faster implementation
As an extension of a renewable energy facility, the storage system often qualifies for priority grid connection under Section 8 of the EEG and, in the case of wind and ground-mounted PV projects, can frequently be included in the existing building permit.
Lower investment costs
No new substation, no new medium-voltage line, no new grid connection.
Synergies in Operations
The site, access routes, monitoring, and maintenance are shared.
Case Study
Storage at the Wind Farm
At a wind farm, Voltfang implemented the battery storage system from the planning stage through to operation.
Performance
Operating Concept
Follow-up order (minimum)
What Made the Difference
Speed of implementation
The operator’s schedule was met.
Full Integration
Voltfang assumes the integration risk at the shared grid connection, including a new metering field to ensure clear balancing group separation.
A Well-Thought-Out Operational Concept
As a green energy storage facility with priority grid access and advantages regarding building permits, with the option to switch to grid power later.
A Responsibility
From procurement and integration to operation and EMS.
White Paper
Energy Storage at Wind and Solar Farms: Operating Concepts, Integration, Revenue
The white paper explains what matters most when it comes to a storage system connected to an existing grid—from operational concepts to technical integration and revenue streams. Free via email.
Frequently Asked Questions About Storage Systems at Wind and Solar Farms
Co-location means that a battery storage system and a power generation facility—such as a wind or solar farm—share the same grid connection point. Both remain independent facilities but share the grid connection, land, and infrastructure. Voltfang plans, integrates, and operates such storage systems at existing and new farms.
A battery storage system at the park captures electricity that would otherwise be curtailed or fed into the grid at very low prices, and releases it when it is more valuable. In addition, it can provide balancing power and trade on the electricity market. Voltfang plans, integrates, and operates such storage systems at the park’s shared grid connection point.
Yes. The park and the storage facility share the grid connection; new grid infrastructure is usually not necessary. Voltfang clarifies the requirements with the grid operator and implements the integration—including a new metering field for clear balancing group separation.
Not if the operating concept is appropriate. A green electricity storage system that charges exclusively from the wind farm retains its green electricity status. Since the Federal Network Agency’s MiSpeL ruling on October 1, 2026, storage systems have also been able to use grid power without losing the subsidy for temporarily stored green electricity; the implementation period runs through the end of September 2027. Voltfang coordinates the appropriate concept with the grid operator early on.
A green energy storage system charges exclusively from the connected wind or solar power plant; the electricity remains green energy. A grid-connected storage system (also known as a “gray” electricity storage system) also charges from the grid and is freely marketed on the electricity and balancing energy markets. Voltfang plans projects in such a way that a later switch remains possible.
Under a flexible grid connection agreement pursuant to Section 8a of the EEG, grid operators and plant operators limit the maximum feed-in at the grid connection point, including on a time-staggered basis. If multiple systems or storage units share a grid connection point, the agreement also governs joint responsibility and liability. Voltfang’s EMS ensures compliance with the agreed-upon limit at all times.
At Voltfang, we manage the integration risk at the shared grid connection—from the metering concept and protection technology to integration into the park control system. You’ll have a single point of contact for the entire project.
Yes, it’s just operated differently. Wind power fluctuates over longer periods than solar power, which is why Voltfang’s EMS combines feed-in shifting with balancing power and electricity trading. Voltfang has implemented such a storage system at a wind farm in Lower Saxony; a follow-up contract for at least 20 MWh has been agreed upon.
The grid connection and permitting process usually set the pace. Voltfang expedites both with template documents, experience, and a green power plan that includes a prioritized grid application where appropriate. We’ll establish the specific timeline after conducting an initial assessment.
Yes. Voltfang’s EMS has open interfaces and is compatible with common marketing platforms. Your existing direct marketing platform can be integrated.