The global energy transition is presenting conventional power grids with immense structural challenges. The increasing share of fluctuating renewable energy sources demands flexible, decentralised solutions to ensure long-term supply security, efficiency and sustainability.
In this changing environment, microgrids offer a promising response by integrating local renewable energy sources, such as solar plants, wind power or biomass, and enabling intelligent control over generation, storage and consumption. Industrial rooftops, in particular, hold vast untapped potential for this transition; the International Energy Agency (IEA) estimates that solar installations on industrial rooftops could reach up to 1,000 GW globally by 2030, representing a quarter of the world's total PV expansion.
Structural concepts and operational advantages of microgrids
A microgrid is a small, localised power supply network that combines renewable and conventional energy sources, capable of operating both while connected to the public grid and autonomously in islanded mode.
- Core backbone infrastructure elements: Generation plants such as photovoltaics, wind power, combined heat and power (CHP) units, or fuel cells form the primary generation layer of the network.
- Energy buffer and grid stabilisation: Energy storage systems, including lithium-ion batteries or green hydrogen storage, buffer excess generation and release it as needed to maintain localised grid stability.
- Minimising transmission distribution losses: By placing producers and consumers in close physical proximity, microgrids minimise transmission losses significantly and enhance overall system efficiency.
- Protection against large-scale blackouts: Small-scale local energy management makes it safer to connect or replace generation units. Because grid sectors can decouple during disruptions, large-scale public grid outages are highly unlikely to affect the facility.
- Direct cost reduction mechanisms: Intelligent control systems optimise energy flow in real time. By maximising self-consumption and using peak shaving strategies, industrial companies can drastically lower their electricity costs.
- Integration of intelligence and long-term storage: Artificial intelligence will play an increasing role in microgrid controls through automated load forecasting, while green hydrogen will increasingly serve as a viable long-term seasonal storage solution.
Real-world industrial deployment at MAN Energy Solutions
The practical implementation of decentralised energy systems is well illustrated by a real-world project at the MAN Energy Solutions manufacturing facility in Augsburg, Germany.
- Ambitious corporate decarbonisation targets: As a Volkswagen subsidiary, MAN Energy Solutions aims to halve CO2 emissions at its global production sites by 2030, a goal requiring immediate changes in its energy supply architecture.
- Electrification of high-temperature process heat: Industrial companies are aggressively moving to electrify process heat, an area responsible for around 75% of industrial greenhouse gas emissions in sectors like steel, chemicals and paper.
- The transition to dynamic network availability: Managing industrial energy networks requires shifting from purely commercial optimisation toward dynamic energy availability and load management across HVAC, lighting and data centers.
- Deploying certified redundant park controllers: To guarantee compliance with legal grid connection requirements, MAN partnered with Bachmann to implement a redundant park controller based on the M200 control system.
- Seamless utility grid integration validation: The certified hardware functions of the Bachmann Smart Power Plant Controller (SPPC) allow the facility to certify its entire power generation and safely interface with the public grid without downstream overload risks. This configuration was successfully validated across two large rooftop PV arrays at the Augsburg site.
Economic viability and strategic recommendations for developers
The broader market for rooftop solar and microgrids is growing rapidly, accelerated by legislative frameworks such as the EU Energy Performance of Buildings Directive (EPBD), which mandates solar installations on all new public and commercial buildings.
- Unlocking massive end-of-decade capacity: Driven by regulatory mandates, the EPBD could unlock an additional 150 to 200 GW of solar capacity on European rooftops between 2026 and 2030, doubling the 170 GW installed base recorded at the end of 2023.
- Strong financial returns on self-consumption: Data indicates that industrial PV systems with self-consumption cover up to 80% of a company's electricity needs, achieving attractive financial returns of 8% to 12% per annum with a short payback period of five to eight years.
- Environmental benefits without land conflicts: Each installed kilowatt-peak of solar capacity saves approximately 500 kg of CO2 annually. Using existing rooftops avoids sealing additional land, thereby increasing public acceptance and preventing land-use conflicts.
- Financing via zero-capital alternative models: Companies can overcome initial investment hurdles by using flexible financing models, such as Microgrid-as-a-Service (MaaS) or long-term Power Purchase Agreements (PPAs), which allow factories to source clean power without upfront capital expenditures.
How is your corporate energy management team evaluating industrial rooftop layouts and certified park controllers to secure energy autonomy and hedge against grid price volatility? Share your thoughts in the comments below.
Looking for the full technical breakdown? To examine the processor architectures, digital input modules and grid measurement hardware supporting the M200 control series, visit the official Bachmann platform at bachmann.info: https://pes.eu.com/exclusive-articles/energy-autonomy-through-rooftop-solar-power