Swissgrid-led study highlights grid challenges, market reforms, and flexibility needs to support rising solar generation toward Switzerland’s 2050 targets
Current grid systems are not fully suited for high volumes of decentralized and variable solar generation, according to the white paper
It calls for flexible grids, storage, market-based signals, and reduced grid connection limits for smoother integration that ensure the system continues to operate smoothly
Switzerland’s grid operator, Swissgrid, along with a group of solar PV experts, has published a white paper that explores how the country can best integrate up to 40 GW of solar PV capacity to the grid, as targeted under its Energy Strategy by 2050.
At the end of 2024, Switzerland had around 8 GW PV capacity installed, comprising annual additions of around 1.8 GW. By 2050, this cumulative total is targeted to expand to 37.5 GW of solar PV, generating 34 TWh of power out of the 45 TWh of renewable electricity annually, excluding hydropower. By 2030, the interim target is 23 TWh of clean energy supply, comprising 18.7 TWh of solar and 2.3 TWh of wind (see Switzerland Targets 18.7 TWh Solar Electricity Production By 2030).
Networks in their current form are designed for large-scale centralized generation, and not for bidirectional load flows and highly fluctuating feed-in and consumption patterns, as is required to accommodate PV generation. A high volume of decentralized generation systems exacerbates the challenge.
Hence, in the white paper titled System-Compatible Integration of Photovoltaics, analysts point out that integration of this capacity under the present framework conditions is not possible. Grid integration also needs to be done in a ‘grid-friendly’ way that continues to support the system.
This will require some fundamental changes, including a reduction in the PV project capacity, market signals, and streamlined processes.
As large power plants phase out, maintaining grid stability will require new technologies, decentralized systems, and clear standards, points out the white paper. It will also be important to have standardized guidelines to manage PV plant responses during outages, communication failures, and cybersecurity incidents.
Reducing grid connection capacity is one of the recommendations. Designing the electricity grid for 100% of the installed PV capacity of up to 40 GW is ‘neither technically nor economically sensible’. Analysts recommend setting limits on installed capacity instead of feed-in, while still allowing self-consumption. Even if the grid connection capacity is reduced to half, only about 15% of the total solar electricity produced in a year would go unused or not be integrated into the grid.
Nevertheless, solar generation must be encouraged to ensure a surplus during the winter months, even if not all of it is utilized.
They also believe that solar power should be used or sold based on market demand to maximize value. There shouldn’t be any financial incentive to feed electricity into the grid if the electricity price is negative. Instead of guaranteed purchase by utilities, operators should rely on market-based selling through service providers.
Another recommendation is to boost storage, smart controls, and flexibility to ensure solar systems remain profitable. Selling this flexibility may become an important source of income in the future.
With more such tools working on the ground, their use must be properly coordinated along with data sharing. To this end, the white paper proposes a central flexibility platform with a coordination mechanism.
“With the current processes and framework conditions, the integration of up to 40 GW of installed PV capacity into the Swiss electricity system is hardly conceivable,” reads the white paper.
It adds, “Taking coordinated action throughout the entire process – by setting requirements for plants and introducing appropriate conditions for operation, marketing and data interchange – is the only way in which the PV capacity desired by policymakers can be successfully and securely integrated into the overall system.”
Earlier this year, Switzerland’s Federal Council said it would introduce amendments to the Energy Act to accelerate the deployment of large-scale solar, wind, and hydropower projects of national interest (see Switzerland To Accelerate RE Projects Of National Interest).