It is already a know fact that Microgrids are spreading globally, driven by technological, regulatory, economic, and environmental factors. Siemens helps build and get the best from these modern energy systems.

To a greater or lesser extent, every business needs access to reliable and economical sources of power. It is an additional bonus for some if that electricity can be generated using renewable sources. Modern technology allows businesses to meet these needs themselves, producing energy as well as consuming it locally, creating flexible networks known as "microgrids."

At the dawn of the electrical age, every grid was a microgrid - a locally limited system in which power was generated and distributed to users. Gradually these were subsumed into larger networks, becoming national or even crossing frontiers. Economy of scale dictated ever larger, usually fossil-fuelled generation plants, supplying often distant cities and industrial centers via transmission at high voltage.

But now the trend has reversed toward generation that is again decentralized, potentially renewably sourced, and often within flexible modern microgrids, able to attach or disconnect from the wider system at will. Microgrid operators can take advantage of management systems able to tell them exactly when it makes sense to generate, when to draw power, and when to sell power to the local utility company. Businesses of various size, whether they use less than 1 or more than 100 MW, are evolving from being passive consumers to becoming active (if assisted) "prosumers."

Different reasons are driving this development across varied environments and customer groups. In Europe, regulated tariffs have risen and subsidies are offered for sales to national grids from renewable sources. This has led, for example, to more than one in six companies in Germany generating their own power. Technology has also assisted, with solar, wind, and gas turbine generation becoming ever cheaper, as has battery/hydrogen storage - all allowing insulation from the uncertainty of future utility tariffs. Microgrids' low voltage distribution achieves less losses than the transmission network, boosting efficiency further still.

For some users, cutting CO2 emissions is also a goal, like the University of Genoa in Savona, Italy, where Siemens helped shape a microgrid based on solar power and micro-gas turbines. The Savona microgrid delivers 250 kW of power and 300 kW of heating for its 40,000 students, and this is viewed as a pilot for an expanded version for the surrounding green-minded city. Such combined heat and power (CHP) or combined cooling, heat, and power (CCHP) features are a common way to achieve still greater efficiency within microgrids.