Changes

Consumption of electricity is measured in kWh which is kilowatt-hours or 1.000 watts per hour. With a price of 35 to 45 eurocent per kWh, this is a commodity worth to think a moment on how to organize the value chain to ensure money can be collected from consumers (Endverbraucher) and distributed to the contributors in the energy industry. The “bottom” end if this value chain is the “electricity bill” (invoice) you are receiving from a '''supplier ''' (Lieferant). As Germany is an open market for electricity, this supplier buys the electric energy for your future consumption from an exchange-like market and/or has means to produce electricity themselves. But this will be covered later in more detail. For the moment we just reduce it to the fact that the supplier estimates your individual consumption of electricity based on a standardized load profile ('''SLP''') and if everything is normal, it will be there to power whatever electric appliances you might have.

In order to “smartify” the situation, communication must be enabled. Therefore an communication interface needs to be added to the smart-meter. Furthermore a smart-meter-gateway ('''SMGW''') needs to be added and accessible from the meters communication interface. These two devices can now communicate and are called in Germany an intelligent measuring system or '''iMSys ''' - and yes, this communication is already protected (encrypted). The protocol used here is a COSEM (Companion Specification for Energy Metering) / OBIS (Object Identification System) / OMS (Operation Management System) protocol based on RS485 which can be either by wire or wireless, defined in [https://www.bsi.bund.de/SharedDocs/Downloads/DE/BSI/Publikationen/TechnischeRichtlinien/TR03109/TR-03109-1_Detailspezifikation.pdf?__blob=publicationFile&v=4 TR-03109]

One or more smart-meters with communication interfaces connect with a single smart meter gateway and form the '''Local Metrological Network ''' or '''LMN'''.

In the HAN you will find all the Controllable Local Systems ('''CLS'''). These are switches controlled by the SMGW and can be turned on or off or put into a “reduced power mode”. This is the sole purpose of the HAN to have access to one or more CLS. Pictures are often shown with including the consumers smart-home components and proprietary in-home-displays ('''IHD'''), but this is just obfuscation. The truth is all consumers will connect their smart home components in their home WLAN and in one way or another directly to the meters for readout or in the case of a power generating situation (photovoltaic, wind, generators) to the inverters / regulators of that generation unit. The CLS sole purpose is reduce the risk of instability for the grid in energy shortage situations and to enable the grid operators to shut down high consumption appliances like professional grade electric heaters, air conditioning, washer and dryers, kitchen ovens, stove, furnaces, wall boxes for e-mobility, instantaneous water heaters and heat pumps. The owner of a house will effectively loose the final control over these appliances if they have been connected through an CLS. As of now, consumers and house owners are tricked into the CLS acceptance process by offering discounts on the price of the kWh. But the national institute for electrical engineering (VDE) is working on standards making it mandatory to connect anything with an electrical power of more than a thousand Watts to a CLS. Making it illegal to constantly operate those without an CLS.

This network carries the communication from the grid operator ('''Gateway-Administrator''') to and from the intelligent measuring System. The gateway administrator is a role. This role is controlled by the grid operator and his rules for redispatch (rules to control frequency in the power grid at a acceptable stable level). That is a very important role and numerous apocalyptic movies do build their plot on the idea of something going wrong here. This role is the true divers’ seat in this orchestra. With CLS the ability to reduce the impact of medium or larger stability incidents to a desired audience of maximum suffering tolerable individuals, the possibilities have substantially increased. Of course, it is up the German government and the minister of energy, to decide how this audience should be exactly composed of.

Also an external market player role ('''externer Markteilnehmer''') is defined. These is for example your energy supplier (Lieferant). He can communicate with the SMGW as well and have it sending consumption-based data in higher or lower frequency or change your tariff. If you for instance, are notorious late with payments, the supplier can switch your invoicing from billing to prepaid and cut you off the grid until a positive balance materializes in the payable account.