## 5 Various Concepts Aligned with the Smart Grid
Integration of smart appliances [7], is done through pieces of smart equipment that can communicate with electric grid. They may be turned off during peak hours. For example, a study on households using smart washing machines reported that demand automatically shifted to periods when electricity is not expensive [75]. Advanced storage and peak-shaving technologies can be used to reduce the peak load [76; 77; 78]. Electrochemical technology-based battery energy storage system (BESS) is mostly used for peak-shaving. Sodium Sulphur (NaS) batteries can be used for peak-shaving  
Figure 9: Basic components of virtual power plant. VPP is formed by combining a group of distributed energy resources (DERs). It also consists of different types of load. It has similar characteristics of conventional generating units in case of total capacity [73]. and power quality (PQ) improvement of the grid. The peak load shaving using BESS is shown in Figure 10[78]. Devices inter-operability show the number and scale of use of smart devices and sub-systems in a smart grid will be very high, which makes the system interoperability crucial [75]. Advanced restoration technique will improve with automatic schemes using advanced measurement, and analysis and control technologies. Some of the concepts can be implemented without major changes in operating procedures. However, there are other concepts that will require some major changes in the operating procedures. Smart Homes and Smart Cities also uses SG. A smart city uses information and communication technologies to increase operational efficiency, share information with the public and improve the quality of government services, etc. A smart home uses IOT devices to enable remote monitoring and management of appliances such as lighting, cooling/heating, and other electric devices. Smart Grid can take active data on the load behavior of these devices and communicate with them in on-peak hours, off-peak hours and request user end adjustments, be it manual or automatic in-built adjustment feature of the smart devices. This can greatly make electricity consumption more efficient in the user ends. Active loads and two-way power flow used in a smart grid allows consumers to have renewable energy generators. The customers can act be consumers and producers of energy, so named as prosumers. As such, the loads will transform from passive loads to active loads. Therefore, the conventional one-way power flow from the utility towards the consumers will change to a two-way power flow. However, a change in regulatory and legal aspects for defining rights, obligations, and liabilities will be required. In addition, the customer needs to be educated that he is no longer still a consumer but an active player with rights and obligations. Smart cities can utilize SG devices which can be seen to be used to gather real time data on traffic, transport, water and energy supply etc. and supply information to cloud for the appropriate authority to monitor and assess the condition of urban areas and act on the collected data. Also, they can be used to convey better public services with respect to particular needs in particular cityscapes. The co-constitution of Smart City and Smart Grid is gaining traction in India, Sweden and many other places, because it provides ease in carbon-governance, policy implementation alongside creating a smart energy system [80]. The co-constitution is highly important because without thinking of a smart energy system, it would be quite complicated to develop a smart city model. Smart Grid has been also defined as one of the fundamental building blocks of a smart grid alongside with smart transportation, smart governance and smart healthcare [81]. A schematic diagram of smart city utilizing the smart grid concept is shown in Figure 11[82]. Figure 10: The peak load shaving technique using BESS. It is the mostly used energy storage system (ESS) for peak-shaving. By using BESS, the PQ of the grid can also be improved [79].