## 2 Demand-Side Management Classifications and Their Roles in Cost Minimization
### Cost Minimization by Employing Efficient DSM Schemes
#### 2.2.1 Game Theoretic and Real-Time Pricing Approaches in Cost Minimization
By solving Equation (4), the demand during peak hours is minimized which results in a flattened demand curve and hence, minimizes the deviation from the grid available load. As we mentioned earlier, in peak hours, the consumers are charged a higher price per unit because of the operating of the peaker power plants to fulfill the consumers' demands. If the load during peak hours is reduced or the high power rating appliances are re-scheduled to off-peak hours, the generation companies will not need to operate additional plants and hence, the cost of generation and the consumers' bills will be minimized. In [91], the authors proposed a framework based on fairness in billing and consumer privacy. According to this framework, an autonomous DSM can work efficiently if the number of consumers contributing to the DSM is increased which can be achieved via coordination and communication among consumers through smart meters. Moreover, to motivate the consumers to participate in the proposed scheme, it is important to devise a fair billing algorithm in the form of incentives for the consumers. **Conclusions of the subsection:** In this subsection, we focused on key performance metrics, i.e., cost minimization. We call them key performance metrics because once the cost is minimized, then most of the other performance metrics are automatically attained. We provided a detailed review of literature from a cost minimization perspective. We divided this cost minimization survey into two subsections i.e., cost minimization using the game theoretic approach and cost minimization using DSM schemes based on RTP. From this subsection, we also identified an open research area including consumer participation in the given DSM, consumer privacy, consumer satisfaction and the implementation complexity of the given DSM model. Therefore, in addition to cost minimization, it is mandatory to converge the attention of researchers towards DSM schemes which can educate the consumers regarding the given DSM to participate in; also, it is crucial to take care of consumer privacy and satisfaction. Moreover, the proposed model needs to be cost-effective and simple to implement. Integration of DERs into the Main Grid and How It Helps to Achieve the Various Performance Metrics of the DSM  
In the traditional power system, most of the electricity production is centralized and is generated through fossil fuel. This centralized energy generation produces plenty of NOx and SOx that is polluting the environment. Besides this, electricity generation using fossil fuels is becoming more expensive day by day due to the increased cost of fossil fuel. Therefore, the organization of environmental protection as well as the high production cost of electricity has forced various government agencies to rethink their energy production resources [35; 146]. The centralized generation of power is not only costly and inefficient, but it is also sometimes not enough to meet the consumers' demands during peak hours [147]. To mitigate this issue, the use of distributed energy resources (DERs) is one of the solutions [148]. DERs can be divided into two different types: DERs with non-renewable sources of energy and DERs with renewable energy sources. (i) DERs with Non-Renewable Sources of Energy  
This type of DER includes diesel generators, gas engine generators, etc. In this case, the DERs generate the energy by using small-sized gas engine generators and diesel generators, but it is not an economical source of generation. (ii) DERs with Renewable Energy Sources  
In this type of DER consists of renewable energy resources, i.e., photovoltaic (PV) cells, wind turbines, small hydel power plants and battery banks for storing the generated energy. Renewable sources of energy are cheaper and green sources of energy [149]. Renewable sources have enough advantages over the diesel and gas generators; however, there are some problems with these sources.