# AC vs. DC Distribution Efficiency: Are We on the Right Path?

^{1}

^{2}

^{3}

^{*}

## Abstract

**:**

## 1. Introduction

## 2. Critique of Various Parameters of AC–DC Distribution System Efficiency

#### 2.1. Critical Review of Load Models Presented in the Past

#### 2.2. Critical Review of the Consideration of PEC Efficiency

#### 2.3. Review of the Consideration of Storage Elements in AC and DC Distribution Studies

#### 2.4. The Choice of Voltage Level in DC Distribution Efficiency Analyses

#### 2.5. Consideration of Line Losses in the Past AC/DC Distribution Efficiency Studies

#### 2.6. Employment of Distributed Generation in AC/DC Distribution Efficiency Studies

_{at}’, ‘E

_{bt}’, and so forth. The denominator sums the overall PV generation.

## 3. An Approach to a Definite AC/DC Distribution System

- Conventional/classical,
- Shifting trend,
- Futuristic.

#### 3.1. Inclusion of PEC Efficiency in System Model

- Loads with a similar rating are lumped and driven by a single converter,

#### 3.2. Inclusion of Storage Elements in System Model

#### 3.3. Selection of Voltage Level in System Model

#### 3.4. Line Loss Consideration

#### 3.5. Inclusion of DG in System Model

## 4. The Future of AC–DC Efficiency Comparison

_{L}’, and solar capacity ‘C’. When the values of these variables are 0.1 pu each, we can consider this state as S1. The variables ‘α’, ‘β’, and ‘γ’ represent the increment and decrement in the values of ‘Ps’, ‘P

_{L}’, and ‘C’, respectively. With an increment in ‘α’ and ‘β’ for the values of ‘Ps’ and ‘P

_{L}’, the system shifts to a new state S6 and vice versa. Similarly, while the system is in S1, an increment in Ps alone would move the system to S2. Figure 9 is an illustration of how the system shifts states as a function of the variation in the values of system parameters; accordingly, the energy savings for all states can be determined in the future for a comprehensive analysis of AC and DC systems.

## 5. Further Research Areas

#### 5.1. Case of Electric Vehicle Penetration

#### 5.2. Economics of Shift from AC to DC systems

## 6. Miscellaneous Topics of Discussion

#### 6.1. Applications That May Inherently Require AC Machines

#### 6.2. Migration from AC to DC

#### 6.3. Hurdles in Shifting from AC to DC Systems

## 7. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

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**Figure 1.**Load model of a typical community distribution system [5].

**Figure 2.**Load model for LED loads [14].

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**MDPI and ACS Style**

Gelani, H.E.; Dastgeer, F.; Nasir, M.; Khan, S.; Guerrero, J.M.
AC vs. DC Distribution Efficiency: Are We on the Right Path? *Energies* **2021**, *14*, 4039.
https://doi.org/10.3390/en14134039

**AMA Style**

Gelani HE, Dastgeer F, Nasir M, Khan S, Guerrero JM.
AC vs. DC Distribution Efficiency: Are We on the Right Path? *Energies*. 2021; 14(13):4039.
https://doi.org/10.3390/en14134039

**Chicago/Turabian Style**

Gelani, Hasan Erteza, Faizan Dastgeer, Mashood Nasir, Sidra Khan, and Josep M. Guerrero.
2021. "AC vs. DC Distribution Efficiency: Are We on the Right Path?" *Energies* 14, no. 13: 4039.
https://doi.org/10.3390/en14134039