8Energies, Enspired and Goldbeck Solar Present White Paper: How Storage Solutions Increase the Profitability of Solar Parks

Berlin / Hirschberg (Germany) / Vienna (Austria) - In light of declining revenues in the solar power market, 8Energies, Enspired and Goldbeck Solar have published a joint white paper on the profitability of so-called “standalone” battery energy storage systems (BESS) at photovoltaic sites.

The paper outlines a scalable approach for integrating battery storage systems into existing and new PV installations with a shared grid connection point (co-location). The aim is to safeguard the long-term profitability of solar portfolios despite increasing market volatility and declining solar revenues.

Solar Power: Market Environment Under Increasing Pressure

According to the authors, the sector is facing structural changes: the so-called solar capture rate has fallen from around 80 percent (2023) to below 58 percent (2025). At the same time, the number of hours with negative electricity prices has nearly doubled.

These developments are leading to declining market revenues and intensifying the economic pressure on pure PV business models. By combining PV systems and battery storage at a shared grid connection point, the companies seek to optimize existing infrastructure.

Cable Pooling: Economic and Technical Synergies

Through models such as cable pooling, infrastructure costs can be shared, thereby reducing capital expenditure. According to the white paper, this can improve the internal rate of return (IRR) for new installations by around 29 percent. For existing installations, IRR increases of up to 24 percent are possible, depending on fee structures and system configuration.

At the core of the concept is so-called joint optimization: using AI-based control algorithms, PV feed-in is curtailed only when battery storage market revenues — for example from ancillary services or arbitrage — exceed the lost solar revenues.

According to the companies, revenue losses for the battery system due to shared grid usage amount to only around 4 percent when intelligent control is applied.

Technical Implementation by Goldbeck Solar

Goldbeck Solar is responsible for the technical integration of the systems. A single-primary control concept coordinates asset management at the grid connection point in compliance with regulatory requirements, including Section 118 of the German Energy Industry Act (EnWG).

In the partners’ assessment, the model transforms the grid connection from a static cost factor into an into an active driver of returns and is intended to accelerate the expansion of battery storage systems in Europe.

Source: IWR Online, 24 Feb 2026