# Economic and Experimental Assessment of KCOOH Hybrid Liquid Desiccant-Vapor Compression System

^{*}

## Abstract

**:**

## 1. Introduction

_{2}), lithium chloride (LiCl), and triethylene glycol (TEG)), and empirical correlations were developed. Dai et al. [7] experimentally investigated a hybrid LDAC system comprised of a VCS, a liquid desiccant system, and an evaporative cooler, and the COP was found to be 1.513, 1.862, and 1.745 while using VCS, VCS + desiccant dehumidification, and VCS + desiccant dehumidification + evaporative cooling, respectively. Al-Farayedhi et al. [8] suggested a system consisting of a packed-bed dehumidifier with a five-ton capacity VCS while employing CaCl

_{2}as liquid desiccant, and results revealed that temperature of the air was reduced from 48 to 38 °C and the value of outlet-to-inlet absolute humidity was found to be 0.6. The COP

_{hybrid}was calculated in three different regeneration modes: 1.164 (while heating desiccant), 1.616 (while heating air), and 1.4221 (while heating both air and desiccant), and the COP of the standalone VCS was 0.989. Lee et al. [9] experimentally investigated a proposed heat pump driven hybrid LDAC system in which the heat pump accommodates the heating and cooling demands of liquid desiccant. The result was that COP was found to be 2.26 in the summer with 7.45 kW cooling capacity and the COP in the winter was found to be 2.51 with 5.075 kW. Guan et al. [10] discussed the performance of an on-site novel hybrid LDAC system in an industrial factory. The COP of the system was 3.6, which was enhanced by 25.6% and saved about 23.3% energy. This is achieved as this proposed system needs chilled water without reheating because of the use of the dehumidifier. Mansuriya et al. [11] performed an experimental study on a small-scale 5 kW hybrid LDAC system in which a VCS unit is employed to enhance the COP

_{hybrid}by 27.54% and the share of total latent heat load (LHL) of the system, 54.93%, is shared by the dehumidifier unit with a payback time of four years. In another study [12], they performed a thermo-economic assessment of the proposed system with COP and annual cost as objectives. The investigation concluded that the COP was improved by up to 68.4% compared to the standalone COP, and the payback duration was found to be 1.54.

_{2}, lithium bromide (LiBr), LiCl, and magnesium chloride (MgCl

_{2}) are the most frequently employed liquid desiccants in LDDS, and their dehumidification and regeneration capabilities are widely utilized in recent engineering applications [15]. LiCl, the most stable liquid desiccant, has the lowest dehydration concentration (30–40%) and the lowest vapor pressure [16]. LiBr is approximately 20% more costly than LiCl, but it possesses the same regeneration and dehumidification capabilities. As the most readily available desiccant, CaCl

_{2}solution has the lowest cost but can be unstable depending on the solution’s concentration and the air conditions at the inlet [17]. Moreover, the dehumidifier in the LDDS system was equipped with an external cold source for internal cooling, consequently lowering the solution temperature and enhancing overall dehumidification capacity. During experiments and technical applications, however, it was noticed that saline liquid desiccant caused severe erosion on metal dehumidifiers, which are typically constructed from metal. Therefore, researchers explore more alternatives for new liquid desiccant solutions.

## 2. Description of Experimental Setup

- The dehumidifier and regenerator are adiabatic with no desiccant carryover.
- The distribution of desiccant solution and air is considered uniform throughout the whole section.
- The interfacial area (area of contact) between air and desiccant is the same.
- The pressure-drop across connecting pipes is considered negligible.
- The exit states of an evaporator and condenser are considered saturated.
- Expansion valve heat loss is negligible.
- Heat transfer resistance is considered more negligible for the liquid phase than that of the gaseous phase.

Parameters | Uncertainty | Range |
---|---|---|

Air temperature | ±0.2 °C | 15–40 °C |

Air relative humidity | ±1% | 45–75% |

Inlet desiccant temperature | ±0.3 °C | 28–35 °C |

Air flow rate | ±3.56% | |

Air velocity | ±0.1 | 2–10 |

COP of a hybrid system | ±5.45% | |

Heat load of dehumidifier | ±5.32% |

## 3. DOE Methodology

#### 3.1. Experimental Design

#### 3.2. Performance Indicators

#### 3.2.1. Dehumidifier Latent Heat Load (${Q}_{deh}$)

#### 3.2.2. Coefficient of Performance of the HLDAC System ($CO{P}_{hybrid}$)

#### 3.2.3. Moisture Removal Rate ($\dot{M}$) (g/s)

## 4. Result and Discussions

#### 4.1. Fitting the Model

#### 4.2. Effect of Input Variables on Response Parameters

#### 4.2.1. Dehumidifier Latent Heat Load

#### 4.2.2. Coefficient of Performance of the HLDAC System

#### 4.2.3. Moisture Removal Rate

#### 4.3. Optimization and Validation of Model

## 5. Comparison of Hybrid System with Conventional VCR Unit

## 6. Economic Assessment

## 7. Conclusions

- The maximum ${Q}_{deh}$ and $CO{P}_{hybrid}$ is obtained when the values of specific air humidity and desiccant concentration are higher with the lowest values of air flow rate and desiccant temperature.
- Highest values of air flow rate, specific air humidity, desiccant concentration, and the lowest value of desiccant temperature yield maximum MRR.
- In the analysis of the results, it was observed that the effect of desiccant concentration has a greater effect on response variables as compared to other input variables.
- In terms of $CO{P}_{hybrid}$, a 28.48% improvement is observed as compared to the standalone VCS. In this scenario, 55.21% of the LHL is shared by the dehumidifier unit.
- The proposed HLDAC system demands an additional initial investment of INR 51,000. However, this hybrid system saves INR 17,712 annually compared to a standalone VCS, with a payback time of 2.65 years assuming an interest rate of 10%.

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## Nomenclature

$A$ | Superficial air flow rate (kg/m^{2}$\xb7$ s) |

${a}_{t}$ | Specific surface area of packing (m^{2}/m^{3}) |

${c}_{p}$ | Isobaric specific heat (kJ/kg $\xb7$ K) |

$CO{P}_{hybrid}$ | Coefficient of performance of hybrid system |

$D$ | Superficial desiccant flow rate (kg/m^{2}$\xb7$ s) |

$ECA$ | Electricity consumption annually (kWh) |

${h}_{fg}$ | Latent heat of evaporation (kJ/kg) |

$\dot{{m}_{a}}$ | Air flow rate (kg/s) |

$\Delta {h}_{abs}$ | Enthalpy of absorption (kJ/kg) |

$h$ | Enthalpy (kJ/kg) |

$H$ | Height (m) |

${h}_{fg}$ | Latent heat of evaporation |

$\Delta {h}_{dil}$ | Enthalpy of dilution (kJ/kg) |

$i$ | Interest rate (%) |

$M$ | Molar mass (kg/kmol) |

${N}_{v}$ | Molar vapor mass transfer flux (kmol/m^{2}s) |

$T$ | Temperature (°C) |

$\dot{Q}$ | Heat load removal rate (kW) |

$Q$ | Heat load (kJ/kg) |

$C$ | Desiccant concentration (kg_{des}/kg_{sol}) |

$\dot{W}$ | Work transfer rate (W) |

$w$ | Specific air humidity (g/kg) |

$\omega $ | Air humidity ratio (kg/kg_{da}) |

$Z$ | Height of dehumidifier/regenerator section |

Greek letters | |

$\Delta $ | Difference or change in quantity |

$\eta $ | Efficiency |

$\varnothing $ | Maintenance factor |

$\lambda $ | Latent heat of condensation (kJ/kg) |

$\xi $ | Cost recovery factor |

Subscripts | |

a | Air side |

$AA-HX$ | Air-air heat exchanger |

$cc$ | Component cost |

$ic$ | Investment cost |

$cond$ | Condenser |

d | Desiccant side |

$deh$ | Dehumidifier |

da | Dry air |

$exp$ | Expansion valve |

$l$ | Liquid phase |

$oc$ | Operating cost |

$p$ | Pump |

$ppm$ | Price of packing material |

$reg$ | regenerator |

$ref$ | reference |

sol | Desiccant solution |

$SW-HX$ | Solution-water heat exchanger |

$v$ | Vapor phase |

1 | Inlet to dehumidifier |

2 | Exit of dehumidifier |

3 | Inlet of evaporator |

4 | Exit of evaporator |

Abbreviations | |

AC | Air-conditioning |

ANOVA | Analysis of variance |

CCD | Central composite design |

COP | Coefficient of performance |

CaCl_{2} | Calcium chloride |

DOE | Design of experiments |

HLDAC | Hybrid liquid desiccant air-conditioning |

KCOOH | Potassium formate |

LHL | Latent heat load |

LDDS | Liquid desiccant dehumidification system |

LDAC | Liquid desiccant air-conditioning |

LiBr | Lithium bromide |

LiCl | Lithium chloride |

MgCl_{2} | Magnesium chloride |

MRR | Moisture removal rate |

RSM | Response surface methodology |

SSV | Sum of squares value |

TEG | Triethylene glycol |

TR | Tons of refrigeration |

VCS | Vapor compression refrigeration system |

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**Figure 5.**Main effect plots for ${Q}_{deh}$ versus (

**a**) ${m}_{a1}$, (

**b**) ${T}_{d1}$, (

**c**) ${C}_{1}$, and (

**d**) ${\omega}_{1}$.

**Figure 6.**Main effect plots for $CO{P}_{hybrid}$ versus (

**a**) ${m}_{a1}$, (

**b**) ${T}_{d1}$, (

**c**) ${C}_{1}$, and (

**d**) ${\omega}_{1}$.

**Figure 7.**Main effect plots for $\dot{M}$ versus (

**a**) ${m}_{a1}$, (

**b**) ${T}_{d1}$, (

**c**) ${C}_{1}$, and (

**d**) ${\omega}_{1}$.

Items | Dimensions/Capacity |
---|---|

Packing length | 0.4 m |

Packing width | 0.4 m |

Packing height | 0.6 m |

Liquid desiccant | Potassium formate |

Centrifugal blower capacity | 140 W (1 quantity) |

Anti-corrosive pump capacity | 0.75 kW |

Sealed compressor capacity | 3.5 kW (1 quantity) |

Axial blower capacity | 140 W (1 quantity) |

Electric heater capacity | 500 W (2 quantity) |

Device | Type | Accuracy | Range |
---|---|---|---|

Thermometer | PT100 RTD | ±0.1 °C | (−50)–200 °C |

Densitometer | Specific gravity hydrometer | ±1 kg/m^{3} | 1000–1400 kg m^{−3} |

Humidity transducer | HF535-W, HC2-S3 | ±1% RH | 0–100% RH |

Anemometer | CP218-BO differential pressure flowmeter | ±2% m s^{−1} | 0–30 m s^{−1} |

Solution temperature | T-type thermocouple | ±0.2 °C | 0–200 °C |

Independent Variables | Symbol | Units | Coded Levels ^{a} | ||
---|---|---|---|---|---|

$-$1 | 0 | $+$1 | |||

Inlet air flow rate | ${m}_{a1}$ | kg/s | 0.05 | 0.07 | 0.09 |

Inlet desiccant temperature | ${T}_{d1}$ | °C | 29 | 32 | 35 |

Inlet desiccant concentration | ${C}_{1}$ | kg_{des}/kg_{sol} | 0.65 | 0.68 | 0.71 |

Inlet specific air humidity | ${\omega}_{1}$ | g/kg | 15 | 20 | 25 |

^{a}—1: low level, 0: middle level, +1: high level.

Run | Independent Variables | Responses Values | |||||
---|---|---|---|---|---|---|---|

${\mathit{m}}_{\mathit{a}1}$ | ${\mathit{T}}_{\mathit{d}1}$ | ${\mathit{C}}_{1}$ | ${\mathit{\omega}}_{1}$ | ${\mathit{Q}}_{\mathit{d}\mathit{e}\mathit{h}}$ | $\mathit{C}\mathit{O}{\mathit{P}}_{\mathit{h}\mathit{y}\mathit{b}\mathit{r}\mathit{i}\mathit{d}}$ | $\dot{\mathit{M}}$ | |

(kg/s) | (°C) | (kg_{des}/kg_{sol}) | (g/kg) | (kJ/kg) | Value | (g/s) | |

1 | 0.05 | 29 | 0.65 | 15 | 14.56 | 1.85 | 1.62 |

2 | 0.09 | 29 | 0.65 | 15 | 12.16 | 1.86 | 1.76 |

3 | 0.05 | 35 | 0.65 | 15 | 8.96 | 1.79 | 1.56 |

4 | 0.09 | 35 | 0.65 | 15 | 7.46 | 1.75 | 1.63 |

5 | 0.05 | 29 | 0.71 | 15 | 24.51 | 2.18 | 1.98 |

6 | 0.09 | 29 | 0.71 | 15 | 22.89 | 2.14 | 2.76 |

7 | 0.05 | 35 | 0.71 | 15 | 17.01 | 1.98 | 1.59 |

8 | 0.09 | 35 | 0.71 | 15 | 15.23 | 1.86 | 1.67 |

9 | 0.05 | 29 | 0.65 | 25 | 14.09 | 1.84 | 1.96 |

10 | 0.09 | 29 | 0.65 | 25 | 12.99 | 1.85 | 2.19 |

11 | 0.05 | 35 | 0.65 | 25 | 9.88 | 1.79 | 1.59 |

12 | 0.09 | 35 | 0.65 | 25 | 7.98 | 1.76 | 1.65 |

13 | 0.05 | 29 | 0.71 | 25 | 25.71 | 2.21 | 2.89 |

14 | 0.09 | 29 | 0.71 | 25 | 23.56 | 2.17 | 3.01 |

15 | 0.05 | 35 | 0.71 | 25 | 19.09 | 1.99 | 1.63 |

16 | 0.09 | 35 | 0.71 | 25 | 18.08 | 1.87 | 1.75 |

17 | 0.05 | 32 | 0.68 | 20 | 14.91 | 1.88 | 1.91 |

18 | 0.09 | 32 | 0.68 | 20 | 12.92 | 1.81 | 2.03 |

19 | 0.07 | 29 | 0.68 | 20 | 16.99 | 1.93 | 2.56 |

20 | 0.07 | 35 | 0.68 | 20 | 11.46 | 1.8 | 1.79 |

21 | 0.07 | 32 | 0.65 | 20 | 8.16 | 1.78 | 1.92 |

22 | 0.07 | 32 | 0.71 | 20 | 17.19 | 2.01 | 2.31 |

23 | 0.07 | 32 | 0.68 | 15 | 11.09 | 1.81 | 1.99 |

24 | 0.07 | 32 | 0.68 | 25 | 14.02 | 1.83 | 2.29 |

25 | 0.07 | 32 | 0.68 | 20 | 12.56 | 1.82 | 2.16 |

Response | Regression Equations |
---|---|

${Q}_{deh}$ | $=$ 167.474 $-$ [613.093 $\times $ ${m}_{a1}$] $-$ [10.0162 $\times $ ${T}_{d1}$] $+$ [22.0152 $\times $ ${C}_{1}$] $-$ [1.98114 $\times $ ${\omega}_{1}$] $+$ [1.125 $\times $ ${m}_{a1}\times {T}_{d1}$] $+$ [35.4167 $\times $ ${m}_{a1}\times {C}_{1}$] $+$ [0.7125 $\times $ ${m}_{a1}\times {\omega}_{1}$] $-$ [5.375 $\times $ ${T}_{d1}$ $\times $ ${C}_{1}$] $+$[0.01725 × T_{d1} × ${\omega}_{1}$] $+$ [2.08333 $\times $ ${C}_{1}$ $\times $ ${\omega}_{1}$] $+$ [3541.74 $\times $ ${m}_{a1}{}^{2}$] $+$ [0.191855 $\times $ ${T}_{d1}$^{2}] $+$ [196.328 $\times $ ${C}_{1}$^{2}] $+$ [0.0022678 $\times $ ${\omega}_{1}$^{2}] |

$CO{P}_{hybrid}$ | $=$ 25.024 $+$ [21.1676 × ${m}_{a1}$] $+$ [0.0755675 $\times $ ${T}_{d1}$] $-$ [76.3839 × ${C}_{1}$] $-$ [0.00620304 $\times $ ${\omega}_{1}$] $-$ [0.260417 $\times $ ${m}_{a1}$ $\times {T}_{d1}$ $-$28.125 $\times $ ${m}_{a1}\times {C}_{1}$] $+$ [0.00625 $\times $ ${m}_{a1}\times {\omega}_{1}$] $-$ [0.479167 $\times $ ${T}_{d1}\times $ ${C}_{1}$] $-$ [0.000042 $\times $ T_{d1}$\times $ ${\omega}_{1}$] $+$ [0.0375 $\times $ ${C}_{1}$ $\times $ ${\omega}_{1}$] $+$ [35.3107 $\times $ ${m}_{a1}$^{2}] $+$ [0.00379159 $\times $ ${T}_{d1}$^{2}] $+$ [71.2492 $\times $ ${C}_{1}$^{2}] $-$ [0.000435028 $\times $ ${\omega}_{1}$^{2}] |

$\dot{M}$ | $=$ $-$ 45.4172 $+$ [0.361111 $\times $ ${m}_{a1}$] $+$ [1.47595 $\times $ ${T}_{d1}$] $+$ [62.7361 $\times $ ${C}_{1}$] $+$ [0.153958 $\times $ ${\omega}_{1}$] $-$ [0.979167 $\times $ ${m}_{a1}\times {T}_{d1}$] $+$ [62.5 $\times $ ${m}_{a1}\times {C}_{1}$] $-$ [0.3375 $\times $ ${m}_{a1}\times {\omega}_{1}$] $-$ [2.01389 $\times $ ${T}_{d1}$ $\times {C}_{1}$] $-$ [0.00733333 $\times $ ${T}_{d1}\times {\omega}_{1}$] $+$ [0.191667 $\times $ ${C}_{1}$ $\times {\omega}_{1}$] |

Regression Coefficients | ${\mathit{Q}}_{\mathit{d}\mathit{e}\mathit{h}}$ | $\mathit{C}\mathit{O}{\mathit{P}}_{\mathit{h}\mathit{y}\mathit{b}\mathit{r}\mathit{i}\mathit{d}}$ | $\dot{\mathit{M}}$ | |||
---|---|---|---|---|---|---|

SSV | SSV | SSV | ||||

Intercept | 12.51 | 644.7 (model) | 1.83 | 0.4621 (model) | 1.98 | 3.98 (model) |

A—Inlet air flow rate | −0.8583 *** | 13.26 | −0.0244 *** | 0.0108 | 0.0956 ** | 0.1644 |

B—Inlet desiccant temperature | −2.91 *** | 152.02 | −0.0800 *** | 0.1152 | −0.3261 *** | 1.91 |

C—Inlet desiccant concentration | 4.84 *** | 420.79 | 0.1189 *** | 0.2544 | 0.1950 *** | 0.6845 |

D—Inlet air humidity | 0.6406 *** | 7.39 | 0.0050 | 0.0005 | 0.1300 *** | 0.3042 |

A^{2} | 1.42 *** | 5.11 | 0.0141 | 0.0005 | −0.0841 | 0.018 |

B^{2} | 1.73 *** | 7.59 | 0.0341 *** | 0.003 | 0.1209 | 0.0372 |

C^{2} | 0.1767 | 0.0795 | 0.0641 *** | 0.0105 | −0.0391 | 0.0039 |

D^{2} | 0.0567 | 0.0082 | −0.0109 | 0.0003 | −0.0841 | 0.018 |

AB | 0.0675 | 0.0729 | −0.0156 *** | 0.0039 | −0.0588 | 0.0552 |

AC | 0.0212 | 0.0072 | −0.0169 *** | 0.0046 | 0.0375 | 0.0225 |

AD | 0.0712 | 0.0812 | 0.0006 | 0.0000625 | −0.0338 | 0.0182 |

BC | −0.4838 ** | 3.74 | −0.0431 *** | 0.0298 | −0.1813 *** | 0.5256 |

BD | 0.2587 ** | 1.07 | −0.0006 | 0.0000625 | −0.1100 ** | 0.1936 |

CD | 0.3125 * | 1.56 | 0.0056 | 0.0005 | 0.0287 | 0.0132 |

R^{2} | 0.9958 | 0.9966 | 0.9627 |

Optimum Condition | Coded Levels | Actual Levels |
---|---|---|

${m}_{a1}$ | $-$1 | 0.05 |

${T}_{d1}$ | $-$1 | 29 |

${C}_{1}$ | $+$1 | 0.71 |

${\omega}_{1}$ | $+$1 | 25 |

Response | Predicted values | Experimental values |

${Q}_{deh}$ | 25.636 | 25.71 |

$CO{P}_{hybrid}$ | 2.209 | 2.21 |

$\dot{M}$ | 2.791 | 3.01 |

Experimental Run | $\mathit{C}\mathit{O}{\mathit{P}}_{\mathit{h}\mathit{y}\mathit{b}\mathit{r}\mathit{i}\mathit{d}}$ | LHL Shared by Dehumidifier (%) | LHL Shared by Evaporator (%) | Improvement (%) |
---|---|---|---|---|

1 | 1.85 | 40.54 | 59.46 | 7.56 |

2 | 1.86 | 41.67 | 58.33 | 8.13 |

3 | 1.79 | 33.73 | 66.27 | 4.07 |

4 | 1.75 | 25.42 | 74.58 | 1.74 |

5 | 2.18 | 53.01 | 46.99 | 26.74 |

6 | 2.14 | 52.65 | 47.35 | 24.41 |

7 | 1.98 | 49.53 | 50.47 | 15.12 |

8 | 1.86 | 41.55 | 58.45 | 8.13 |

9 | 1.84 | 39.99 | 60.01 | 6.97 |

10 | 1.85 | 40.57 | 59.43 | 7.56 |

11 | 1.79 | 34.01 | 65.99 | 4.07 |

12 | 1.76 | 28.41 | 71.59 | 2.32 |

13 | 2.21 | 55.21 | 44.79 | 28.48 |

14 | 2.17 | 52.03 | 47.97 | 26.16 |

15 | 1.99 | 51.01 | 48.99 | 15.69 |

16 | 1.87 | 41.87 | 58.13 | 8.72 |

17 | 1.88 | 42.67 | 57.33 | 9.31 |

18 | 1.81 | 36.89 | 63.11 | 5.23 |

19 | 1.93 | 43.86 | 56.14 | 12.21 |

20 | 1.8 | 34.78 | 65.22 | 4.65 |

21 | 1.78 | 32.98 | 67.02 | 3.48 |

22 | 2.01 | 51.89 | 48.11 | 16.86 |

23 | 1.81 | 37.75 | 62.25 | 5.23 |

24 | 1.83 | 39.31 | 60.69 | 6.39 |

25 | 1.82 | 38.81 | 61.19 | 5.81 |

Component | Investment Cost | Selection and Applicability of the Equations |
---|---|---|

SW-HX | ${C}_{SW-HX}=$ 100 $\times $ ${\left({A}_{SW-HX}\right)}^{0.6}$ | Applicable for aluminum plate fine HE [45] |

Pumps | ${C}_{pump}=$2100 $\times {\left(\frac{\dot{W}pump}{\mathrm{10,000}}\right)}^{0.26}\times {\left(\frac{1-{\eta}_{p}}{{\eta}_{p}}\right)}^{0.5}$ | Power law relations for single pass pump [46,47] |

Condenser | ${C}_{Cond}=$ $8000\times {\left(\frac{{A}_{cond}}{100}\right)}^{0.6}$ | |

AA-HX | ${C}_{AA-HX}=$ 8000 $\times {\left(\frac{{A}_{AA-HW}}{100}\right)}^{0.6}$ | |

Compressor | ${C}_{comp}=\frac{39.5\times \dot{{m}_{ref}}}{\left(0.9-{\eta}_{comp}\right)}$ | Applicable for fin based HE with area in range of 4.65–836 m^{2} [48] |

Evaporator | ${C}_{evap}=231\times {\left({A}_{evap}\right)}^{0.693}$ | |

Expansion valve | ${C}_{exp}=114.5\times {\dot{m}}_{ref}$ | |

Dehumidifier/regenerator | $\begin{array}{c}{C}_{deh}={C}_{column}+{C}_{packing}\\ {C}_{column}=583.6\times {H}_{deh}\times {d}_{deh}{}^{0.675}\times {\left(\frac{14.5\times {P}_{atm}}{50}\right)}^{0.44}\\ {C}_{packing}={C}_{ppm}\times {h}_{deh}\times \frac{\pi \times {d}_{deh}{}^{2}}{4}\end{array}$ | Applicable for cylindrical packed towers with random Raschig rings for any column dimensions [49] |

Item | Value |
---|---|

Overall heat capacity of proposed system | 6 kW |

Capital investment of VCS unit with heater | INR 48,000 |

Capital investment of HLDAC system | INR 99,000 |

Extra Expenditure ($\Delta $EE) | INR 51,000 |

Power consumed by VCS unit | 3 kW |

Power consumed by HLDAC system | 2 kW |

Average electric unit price | INR 6.15 per kWh |

Annual operating cost of HLDAC system | INR 35,424 |

Annual operating cost of VCS unit | INR 53,136 |

Annual savings on electricity | INR 17,712R |

Payback period (PP) | 2.65 years |

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## Share and Cite

**MDPI and ACS Style**

Kumar, K.; Singh, A.
Economic and Experimental Assessment of KCOOH Hybrid Liquid Desiccant-Vapor Compression System. *Sustainability* **2022**, *14*, 15917.
https://doi.org/10.3390/su142315917

**AMA Style**

Kumar K, Singh A.
Economic and Experimental Assessment of KCOOH Hybrid Liquid Desiccant-Vapor Compression System. *Sustainability*. 2022; 14(23):15917.
https://doi.org/10.3390/su142315917

**Chicago/Turabian Style**

Kumar, Kashish, and Alok Singh.
2022. "Economic and Experimental Assessment of KCOOH Hybrid Liquid Desiccant-Vapor Compression System" *Sustainability* 14, no. 23: 15917.
https://doi.org/10.3390/su142315917