*4.5. Electric Vehicle (V2G)*

Vehicle-to-grid (V2G) is a system in which plug-in electric vehicles (PEVs), such as battery electric vehicles (BEVs), plug-in hybrids (PHEVs), and hydrogen fuel cell electric vehicles (FCEVs), communicate with the power grid to sell demand response services by returning electricity to the grid or throttling their charging rate. Electric vehicles with V2G storage capability can store and discharge power generated from renewable energy sources such as solar and wind, with output that varies based on weather and time of day [25,26]. The process of V2G is the same as in the case of the ESS shown in Figure 6.

**Figure 6.** Electric vehicle as a source of energy.

### **5. DSM Using DGs and ESS**

DSM is the systematic energy management in the case of using DGs and ESS. Using DSM can have a lot of benefits to industry, residents, nations, and the globe, which is shown in Figure 7. DSM can be implemented by using distributed energy resources such as solar, wind, waste-to-energy, etc. DSM generally involves load shape modification by applying different optimization techniques [27–29]. This modification is carried out by the significant DSM component, which is the load duration curve (LDC). LDC offers a general and analytical idea of off-peak hours and peak hours. Six techniques are used in load shaping, which are discussed below and in Figure 8.

a. *Peak Clipping*: This technique is used to reduce the peak demand at peak hours. Effective use of this method can reduce the chances of establishing new generating stations. Generation from DERs also helps in balancing load and can reduce the peak demand.


**Figure 7.** Benefits of using DGs and ESS in DSM.

**Figure 8.** DSM techniques.

The discussed DSM objectives can be achieved by integrating the DERs described in earlier sections in a forecasted manner [29]. The reason for using all these renewables is as simple as the UN's Sustainability Goal of cleaner energy. Different types of available DERs and possible DSM techniques are discussed in Table 1, which is a new and innovative way of expressing the information in this paper.

**Table 1.** Different types of DERs with DSM applications.


### **6. Energy Management System**

An energy management system is an operational system used to plan, manage, mitigate, forecast, and continuously improve energy performance to establish a balance in the power flow network, including various DERs, as shown in Figure 9. An EMS optimizes the energy supplied by generating stations to the grid, taking into account various parameters, which are listed below:


Major components of EMS are measuring units, IoT-based tools to forecast data from collected data, various types of sources of generation, and generation scheduling. An EMS is operated by various optimization models with specific objectives, taking into account the constraints related to them, which are discussed in the later section.

### *6.1. Energy Monitoring, Measurement, and Analysis*

An EMS includes monitoring, measuring, and analysis as major components to carry forward its operations, which will determine the energy flow performance and help it perform DSM effectively. Its key characteristics include [9,39]:


## *6.2. Standards Used for Communications in DSM Using DGs and ESS*

There are specific standards used for communicating various DGs and ESS to the SG's power flow network, which are provided in Table 2 [40].


**Table 2.** Standards used for communication in DSM using DGs and ESS.
