In the past centuries electricity networks and their control systems were usually centralized as main sources of energy were traditional power stations: thermo, nuclear power and hydro power stations. Due to centralized production and fixed transmission grid, whole system was reasonably simple manageable from central point. With introduction of renewable energy sources like wind and photovoltaic stations a lot of dynamic changes were introduced, mainly due to the nature of such stations. To handle those requirements and improve overall system stability “smart grid” systems were developed that integrates electrical grid with information technology and communication networks.

New technological solutions in the smart grids network enables efficient and cost-effective integration of consumers and small energy production resources.

In Europe, smaller industrial and residential customers represents almost 50% of electricity consumption. For active participation in the smart grid system consumer/producer (prosumer) needs to install the appropriate equipment, which should be in accordance with system requirements but still with price, appropriate to the type of the user. The aim of the project was development and implementation of an acceptable and efficient Smart grids interface in the market segment of large residential and small industrial users.

Smart Grid Interface for larger residential and small industrial users is no longer a passive element in the electrical network, but can act as an active and autonomous part, which optimizes the costs of energy consumption, participates in the energy trade offers and helps to stabilize the energy systems. It allows the integration of the power sources installed at the clients to the wider energy network.

The interface allows active participation in smart grid systems. Despite the integrated capability the interface is affordable and it is simple for use. It includes different communication devices, embedded algorithms and integrates security level at the information exchange. Complex units (smart appliances) could be connected via their builtin communication options, or via the ZigBee wireless communications. The heart of the interface is ARM microcontroller with a supporting real-time operating system. Main communication port is built in Ethernet port, with the TCP/IP protocol stack. Interface is typical IoT element which use cloud computing services for obtaining aggregate inputs from SmartGrid operator and other cloud computing services needed for short and medium term consumption/production forecasts (like weather forecasts).

Implementation of the Smart Grid Interface for larger resident users and smaller industrial users introduce their active role in the smart grid environment and enables cost savings at electricity use, which is estimated at 5-10% of the total electricity energy costs of larger residential or smaller industrial customer. The effects would need to be significant even at the level of the total electrical energy consumption, as the multitude of such users can contribute to the electricity balance.

The target users are the larger residential and a smaller industrial users such as, larger residential community with the common units for cooling/heating, residential units with swimming pools, the larger residential units with installed renewable energy systems, small and medium enterprises with installed electrical power of up to 200kW. It could manage also energy storage subsystems like integration of fuel cell based cogeneration unit. The smart grid interface was developed under the Competence Centre KCSTV in cooperation between INEA d.o.o. and Jozef Stefan Institute.