# Electricity Losses in Focus: Detection and Reduction Strategies--State of the Art
These losses occur primarily during the transmission and distribution of electricity and are attributable to various factors, including conductor resistance, transformer losses, leakage currents, and magnetic losses. These losses can be quantified by applying specialized formulas that consider the specific technical parameters inherent in the network and its component equipment. Formula (1) represents the general calculation equation for determining the electricity losses. \[\Delta E=E_{in}-E_{out}, \tag{1}\]  
where,  
\[E_{in}=\sum_{1}^{n}\left(E_{pi}-E_{pos,i}\right)+\sum_{1}^{n}E_{impj}, \tag{2}\]  
\[E_{sold}=\sum_{1}^{n}E_{si}+\sum_{1}^{n}E_{expj}, \tag{3}\]  
The following variables are to be considered:  
* \(\rm{E_{pi}}\) the energy produced in plant i;
* \(\rm{E_{pos,i}}\) the energy consumed for the services of plant i;
* \(\rm{E_{si}}\) the energy sold in node i;
* \(\rm{E_{imp,j}}\) the energy imparted on the j line;
* \(\rm{E_{expj}}\) the energy exported on the j line [2]. Depending on the particulars of their occurrence and the specific location of the losses, there are several categories of losses in electricity grids. Consequently, electricity losses are classified into two primary categories: technical losses, attributable to technical components within the network, and non-technical losses, arising from external interventions on the electricity networks that do not involve technical elements. Given the significance of this issue, numerous researchers have focused on it to identify and implement novel methods to minimize technical losses in grids and to reduce or even prevent non-technical losses. The subsequent discussion will address the primary issues associated with both technical and non-technical losses, and their impact on the effective functioning of the entire power system [3]. The significance of the identification of power losses and proposing methods to reduce them contributes to optimizing the efficiency of the distribution system through the operation, design, and planning of power networks. In most cases, energy losses, irrespective of their category, impact the compensation of power systems and, consequently, revenues. The present study undertakes a comprehensive examination of the subject, delimitation losses associated with power grids into four overarching categories: power grid stability and reliability, energy efficiency, operational cost reduction, and their environmental impact [4]. The Sankey diagram in Figure 1 provides a visual representation of the energy losses that have been registered within the power system. A comprehensive investigation into energy losses was conducted, with particular attention devoted to the legal requirements imposed by the ANRE (National Energy Regulatory Authority, Romania). The legislative regulations and constraints regarding the determination and identification of energy losses in electricity networks were identified as the fundamental basis for implementing the exposed methodologies. Therefore, the primary objective of the present study has been investigated and validated in terms of legislation and general applicability challenges.