RETRACTED ARTICLE: Evaluating an economic application of renewable generated hydrogen: A way forward for green economic performance and policy measures

Abstract

Energy security and environmental measurements are incomplete without renewable energy; therefore, there is a dire need to explore new energy sources. Hence, this study aimed to measure the wind power potential to generate renewable hydrogen (H₂), including its production and supply cost. This study used first-order engineering model and net present value to measure the levelized cost of wind-generated renewable hydrogen by using the data source of the Pakistan Meteorological Department and State Bank of Pakistan. Results showed that the use of surplus wind and renewable hydrogen energy for green economic production is suggested as an innovative project option for large-scale hydrogen use. The key annual running expenses for hydrogen are electricity and storage costs, which have a significant impact on the costs of renewable hydrogen. The results also indicated that the project can potentially cut carbon dioxide (CO₂) pollution by 139 million metric tons and raise revenue for wind power plants by US$2998.52 million. The renewable electrolyzer plants avoided CO₂ at a rate of US$24.9–36.9/ton under baseload service, relative to US$44.3/ton for the benchmark. However, in the more practical mid-load situation, these plants have significant benefits. Further, the wind-generated renewable hydrogen delivers 6–11% larger annual rate of return than the standard CO₂ catch plant due to their capacity to remain running and supply hydrogen to the consumer through periods of plentiful wind and heat. Also, the measured levelized output cost of hydrogen (LCOH) was US$6.22/kgH₂, and for the PEC system, it was US$8.43/kgH₂. Finally, it is a mutually agreed consensus among environmental scientists that the integration of renewable energy is the way forward to increase energy security and environmental performance by ensuring uninterrupted clean and green energy. This application has the potential to address Pakistan’s urgent issues of large-scale surplus wind- and solar-generated energy, as well as rising energy demand.

Introduction

Pakistan has a severe electricity crisis; for example, the energy demand-supply deficit in Pakistan is roughly at 5500–6000 megawatt (MW) and total blackouts occur 12–18 h per day. The Pakistani government spent US$9 billion in 2008 and 2009 to close the troubling difference between electricity demand and availability, which placed a strain on the country’s economy (Anh Tu et al. 2021; Iqbal et al. 2019b). Furthermore, emerging countries are affected by climate change problems related to global warming; for example, Pakistan’s temperature has risen dramatically in recent decades (Chien et al. 2021d; Nawaz et al. 2021a, b; Xueying et al. 2021). Because of the detrimental impacts of global change, such as drought, increasing sea levels, decreased crop yields, and the resulting impact on health and poverty, these issues are worth investigating. In comparison to fossil fuel oil, several energy sources include high-productivity hydrogen energy with a significant amount of energy; efficient hydrogen production are biomass, solar, and wind (Chien et al. 2021f; Ehsanullah et al. 2021; Jahangiri et al. 2020). Currently, conventional energy sources have taken up a majority of Pakistan’s energy, contributing to global warming and climate change (Anh Tu et al. 2021; Chien et al. 2021a; Chien et al. 2021d). One of the leading environmental threats of the twenty-first century is climate change caused by anthropogenic greenhouse gas (GHG) pollution. The Intergovernmental Panel on Climate Change (IPCC) has proposed several options to reduce GHG pollution.

CO₂ emissions are responsible for 75% of anthropogenic GHG emissions (Khan and Tariq 2018); hence, lowering them will have the most significant impact on mitigating global warming. These guidelines, such as the use of intermittent green energies, are on target to keep global warming below 2°C, but in order to analyze electricity, one needs to consider the electricity market (VRE) (Jin et al. 2020). Since Pakistan is the world’s sixth-largest nation and has a rapidly increasing population, the negative consequences of climate change may be extreme (Mohsin et al. 2020; Mohsin et al., 2018c; Mohsin et al. 2021a). Like China, increased energy demand has resulted from increased population and better living conditions (He et al. 2021a; Liu et al. 2020a; Zhu et al. 2018). More than 140 million Pakistanis suffer regular power shortages for 12–18 h or do not have connections to the national power grid, resulting in an annual candle and kerosene spending of approximately US$2.3 billion. Due to this, many experts have called for sustainable and indigenous resources to meet expected energy demand, for example, wind and solar energies. Researchers Tiep et al. (2021) and Baloch et al. (2020) have concluded in the literature that rising energy demands could encourage environmental laws that support sustainable energy use, since continued use of carbon-based nonrenewable sources could cause climate change natural disasters, such as coastal storm waves, warm summers, unpredictable weather, and flooding. As a result, various mitigation measures have been implemented to mitigate the impacts of environmental destruction. Additionally, Pakistan is continuously ranked among the most affected countries in the global climate risk index which has already claimed the lives of thousands of Pakistanis and is amounted to 1.1% of the overall GDP (Sun et al. 2020c).

As a result, quantifying and qualifying the potential economic and environmental benefits of generating sustainable hydrogen (H₂) solely from wind power is crucial (Feng et al. 2020). Many research have investigated the architecture and application of sustainable hydrogen systems using different quantitative and computational methods to establish an optimum energy balance. According to Bamisile et al. (2021a), hydrogen can outperform the carbon-free energy systems. However, the equipment costs, especially electrolyze costs, are the most significant during the hydrogen systems construction (Alemzero et al. 2020b; Alemzero et al. 2020a; Sun et al. 2020c). Therefore, wind-generated renewable hydrogen source can be integrated with the current nonrenewable energy sources. This will help developing countries to improve their energy self-sufficiency and stability, as well as reducing carbon emissions (Nawaz et al. 2021a; Alemzero et al. 2020a), by broadening their energy portfolio and reducing their dependence on nonrenewable sources (Chien et al. 2020; Huang et al. 2020; Iqbal et al. 2019a).

Hydrogen dioxide, like all natural gas and oil, does not occur in nature. Water (Tolliver et al. 2019), wood, coal, methane, and biological sources (Taghizadeh-Hesary et al. 2020) can all be used to extract hydrogen. However, to produce hydrogen from these current resources, they must be found in abundance and sufficient continuously (Sun et al. 2020a). On the other hand, fuel cell–powered applications have been produced but are currently prohibitively (Lei et al. 2021; Zhao et al. 2020; Yang et al. 2020; Zuo et al. 2020). However, with further research and development, these inventions are expected to reach a cost-effective spectrum. When fossil resources become scarce, hydrogen fuel cell cars are anticipated to supplant conventional gasoline vehicles. Currently, hydrogen processing using wind energy during the electrolysis phase is thought to emit the least amount of GHG compared to other hydrogen production methods (He et al. 2021b; Zhang et al. 2020a, b, 2021b). Furthermore, among the green energy sources, wind-generated power has the lowest cost per kilowatt hour (Li et al. 2021b; Sadiq et al. 2021).

The contribution of this paper lies in the following aspects: (i) Our key aim is to identify the most cost-effective method for producing sustainable hydrogen from electricity produced by wind turbines. We have measured the wind power potential and economic viability of wind-generated renewable hydrogen to initiate the feasibility of clean fuel; (ii) we have also measured the electrolysis cost of wind-generated renewable hydrogen and the relative efficiency of the given renewable energy source for hydrogen production, which is calculated based on their respective variables; (iii) this study’s outcomes can be generalized for policymaking in developing countries such as Pakistan, which owns the same environment, climate, economic, and energy characteristics of economic and environmental vulnerability. As there is a considerable gap in the literature of hydrogen energy feasibility for developing economies, the current study will fill the gap on methods, techniques, and evaluation processes of hydrogen energy project feasibility from different angles; and (iv) the wind-generated renewable hydrogen production and levelized costs have been evaluated since it is the only near-term choice in the scale considered. This study measures the production and supply cost of wind-generated renewable hydrogen. The net costs of the delivery chains were estimated in the viability report. The costs of delivery are often compared to on-site hydrogen development through water electrolysis, an alternate method of supplying hydrogen to industrial hydrogen consumers, which are limited by the expense of on-site development. Lastly, we have proposed a policy framework for policymakers and decision-makers based on the achieved outcomes.

The rest of the paper is organized as follows: (1) the “Wind power potential and energy security” section explores the wind power potential, (2) the “Data and methodology” section explains the methodology, (3) the “Results and discussion” section describes the results and discussion, and (4) the “Conclusion and policy implication” section concludes the study.

Wind power potential and energy security

The increased usage of green energy can help to establish a carbon-free energy zone and reduce the volatile existence of the clean energy market, which faces the greatest obstacle in ensuring a constant supply due to its erratic nature (Agyekum et al. 2021; Chien et al. 2021c; Sun et al. 2020b; Zhang et al. 2021a). Using wind to generate energy is the cheapest of all alternative energy sources. Around a decade earlier, Khodabandehloo et al. (2020) concluded that photovoltaic energy generation usually is more costly than wind energy systems. However, little research were conducted in this area. The ability to produce hydrogen solely from wind energy through electrolysis has received a lot of attention worldwide. Despite possessing many resources, Pakistan has made few attempts to explore renewable energy sources, which prompted the current study (Chien et al. 2021b; Iqbal et al. 2021; Li et al. 2021a, b). Pakistan, a country of South Asia, has a nearly constant wind speed in certain parts of the country with the proportion of windy areas being determined using the total land area. The average installed energy per square kilometer of wind power field is projected by traditional calculations to be 5 MW to assess the output of wind power (Othman et al. 2020; Zhang et al. 2021a). Table 1 shows the cumulative capacity of wind resource evaluation in numerical terms. As a result, the overall ability of wind energy generation is estimated to be approximately 349 GW.

Table 1 Wind resource classification

Pakistan has favorable offshore wind power capacity and onshore wind energy potential which could account for a significant portion of electricity generation. Moreover, using offshore resources will help Pakistan to tackle the country’s air pollution problems. It is known that renewable technology holds a lot of promise, and this has piqued people’s attention. There are several benefits to renewable energy networks, such as reducing economic risk factors, and they are unaffected by variations in fuel availability and costs (Anser et al. 2020a; Baloch et al. 2020); Hsu et al. 2021; Chien et al. 2021e). Geographically, renewable energy is more uniformly spread. Furthermore, federal legislation in the USA power grid has resulted in significant progress and incentives for clean energy production and implementation (Pan et al. 2019). Renewable technology is projected to receive potential consideration in the domestic energy market as our awareness of the environmental effects of fossil fuel combustion grows (Anser et al. 2018; Anser et al. 2020b; Anser 2019). The most significant impediment to large-scale clean energy deployments right now is the high upfront capital costs compared to traditional power sources. Any renewable energy systems that use hydro, wind, photovoltaic, tidal, and ocean resources can only generate electrical energy, which has a higher value than heat (Mohsin et al. 2021). Nonetheless, biomass systems that can produce both heat and energy, as well as geothermal and solar systems (Yumei et al. 2021), are all in the research and developmental stage.

Renewable electricity is more evenly spread across the world than fossil fuels and is usually less sold in the market. Renewable technology encourages the introduction of various renewable energy sources, decreases energy imports, lowers the economy’s market sensitivity (Xu et al. 2020; Sadiq et al. 2020; Ahmad et al. 2020), and offers ways to improve global energy security (Shah et al. 2019; Mohsin et al. 2018a; Mohsin et al. 2018b; Mohsin et al. 2021a; Nguyen et al. 2021). Renewable energy sources may also help improve energy supplies’ efficiency, particularly in areas where grid connectivity is often limited (Shair et al. 2021). In addition, Sueyoshi and Yuan (2017) found that a varied energy mix, good management, and device architecture will help to improve security. Renewable electricity sources, including solar and wind, are inherently sporadic. Instead of burning fossil resources, renewable energy sources absorb energy from the atmosphere (such as coal, oil, natural gas, and uranium). The sun is the ultimate provider of green resources accessible to humanity (Wang et al. 2019; Yue et al. 2017). The overall radiant energy flux that the earth intercepts from the sun is far greater than any existing green energy solutions that capture power. Although in theory, a significant amount of energy is available from the sun, collecting and using this energy in a cost-effective manner remains a challenge ( Jun et al. 2020; Lin et al. 2020; Liu et al. 2020b). Electricity is becoming a strategic asset as technical change accelerates and in industries, such as agriculture and manufacturing, become more mechanized (Bortoluzzi et al. 2021; Mora-Rivera et al. 2020). Therefore, a systematic evaluation of the use of wind and alternative energy in developed countries is one such solution. Such analyses may be carried out in the framework of a green energy viability study to entice prospective investors to invest in the renewable energy market (Ikram et al. 2019a; Ikram et al. 2019b ; Mohsin et al. 2020; Sun et al. 2019).

Brief literature review

Chien et al. (2021d) who measured the capacity for wind energy production in China revealed that this area had a peak annual average wind energy density of 429 W/m², indicating an excellent investment prospect. Another researcher, Bortoluzzi et al. (2021), conducted an economic-technical study in Taiwan to assess the suitable wind turbines for wind power ventures based on several characteristics such as the annual electricity production, financial metrics, fossil fuel usage reduction, CO₂ reduction, and turbine power factor. Besides, hydrogen generation capacity from clean energy sources is being investigated (Wu et al. 2021; Zhuang et al. 2021), and renewable resources, such as solar energy, geothermal energy, oil palms, and biomass, have been identified as potential hydrogen energy sources. Among these resources, solar energy production costs were reported to be 6 to 18 times higher than renewable energy and wind turbine systems (Alvarez-Herranz et al. 2017; Wu et al. 2021).

From the literature review, it is critical to assess the potential for renewable hydrogen generation from wind energy (Seker and Aydin 2020), which is in abundance in Pakistan. Therefore, we developed a novel statistical evaluation of renewable energy indicators in off-grid and remote regions, including wind-generated renewable hydrogen, to improve energy security and reduce continuous emission levels in the field. This research aims to explore the techno-economics of sustainable hydrogen production utilizing wind energy in various windy locations in Pakistan’s Sindh Province. The levelized cost of wind energy was also estimated to determine the cost of hydrogen output (Bamisile et al. 2021b; Ozturk and Dincer 2021).

Data and methodology

Hydrogen production from water electrolysis is a suitable way to maintain efficiency performance of 80–90% and has demonstrated considerable potential to be used in a variety of hydrogen production technologies (Awaworyi Churchill et al. 2020; Bhattacharyya 2019). To calculate the amount of renewable hydrogen produced from wind energy, Eq. (1) is used

$$ h=\frac{\upeta_{\mathrm{el}}{\mathrm{E}}_{\mathrm{out}}}{{\mathrm{ec}}_{\mathrm{el}}} $$

(1)

where h is the amount of hydrogen generated; E_out is the wind electricity input to the electrolyzer for hydrogen production; ec_el is the electrolysis process performance, which ranges between 80 and 90%; and η_el is the electrolyzer energy consumption, which is normally 5–6 KWh/Nm³. The ∆H value of 286 kJ/mol is needed for the decomposition of water (H₂O) to produce H₂. The ultimate chemical reaction of water electrolysis can be written as:

$$ {\mathrm{H}}_2\mathrm{O}\to {\mathrm{H}}_2+\frac{1}{2}{\mathrm{O}}_2 $$

(2)

The reaction’s charge transfer and enthalpy shift determine the thermoneutral voltage V_TH as shown in Eq. (3).

$$ {V}_{TH}=\frac{\Delta \mathrm{H}\kern0.5em }{2F} $$

(3)

where F shows the molar charge constant, which is measured in efficiency. In relation to V_TH of n number of cells, electrolyzer process performance (η_el) can be measured almost precisely by electrolyzer voltage (V_el) according to Eq. (4).

$$ {\eta}_{el}\approx \frac{1.48n\kern0.5em }{V_{el}} $$

(4)

Overvoltage is caused by a variety of failure factors, including physical, electrochemical, and transmission-related losses, which increase in proportion to the current density (Ogura 2020). When attached to a wind turbine, the electrolyzer can run on any current and power speeds.

The total cell reaction response (${E}_{cell}^{\mathrm{o}}\Big)$ is the sum of the voltages of the reduction (${E}_{red}^{\mathrm{o}}$) and oxidation (${E}_{ox}^{\mathrm{o}}$) half-reactions. The calculation is shown in Eq. (5).

$$ {E}_{cell}^0={E}_{(ox)}^0+{E}_{(red)}^0 $$

(5)

The capacity of an isolated half-cell cannot be calculated explicitly. As a comparison, the normal hydrogen half-reaction was chosen and given a standard reduction potential of exactly 0.000 V, shown in Eqs. (6), (7), and (8).

$$ 2{H}_{(1M)}^{+}+2{e}^{-}\kern0.5em ={H}_{2\left(1\mathrm{atm}\right)}\kern0.75em \left({E}_{\mathrm{red}}^o=0.00V\right) $$

(6)

And

$$ {\displaystyle \begin{array}{c}\left(\mathrm{Anode}\right)\kern0.5em Z{n}_{(s)}\to Z{n}_{(aq)}^{2+}+2{e}^{-}\kern0.75em (oxidation)\ {E}_{Zn/Z{n}^{2+}}^o=0.76V\\ {}\left(\mathrm{Cathode}\right)\kern0.5em C{u}^{2+}+2{e^{-}}_{.}\to C{u_{(s)}}^{.}(reduction)\ {E}_{C{u}^{2+}/ Cu}=0.34V\end{array}} $$

(7)

Therefore

$$ {\displaystyle \begin{array}{c}{E}_{\mathrm{cell}}^o={E}_{(ox)}^o+{E}_{(red)}^o\\ {}{E}_{\mathrm{cell}}^o=0.76+0.34V\\ {}{E}_{\mathrm{cell}}^o=1.10V\end{array}} $$

(8)

The levelized cost of energy is a useful metric for comparing the unit costs of various technologies over their economic levelized cost of electricity (LCOE). The LCOE approach is often used as a benchmarking technique to compare the costs of different electricity production technologies (Tehreem et al. 2020; Xu et al. 2020; Yousaf et al. 2020). Wind power economics are determined by various factors, including net construction costs, energy generation, repair and operating costs, location selection, and wind turbine characteristics. The ratio of increasing NPV of total costs (PVC) to total energy (E tot) generated through the device is used to estimate the wind per unit cost (C_W), s shown in Eq. (9).

$$ {C}_{\mathrm{W}}=\frac{PVC}{E_{\mathrm{tot}}} $$

(9)

Electrolysis cost

Previous studies have suggested an electrolyze economic model, in which the electrolyze expenditure consists of three major costs: cash, operational, and repair and replacement. The overall cost of the electrolysis cell is determined by the amount of hydrogen that can be generated, whereas electrolyzer capital cost is determined by the necessary rate of hydrogen supply (Kazmi et al. 2019). The efficient electrolyzer performance and the average real capital cost per kWh at the nominal output are calculated as Eqs. (10) and (11) below.

$$ {C}_{\mathrm{el}\mathrm{e},\kern0.5em \mathrm{u}}=\frac{M_{{\mathrm{H}}_2}{K}_{\mathrm{el},\mathrm{th}}}{8760.f{\eta}_u} $$

(10)

$$ {C}_{\mathrm{el}\mathrm{e},\kern0.5em \mathrm{u}}=\frac{M_{{\mathrm{H}}_2}{K}_{\mathrm{el},\mathrm{th}}}{8760.f{\eta}_u} $$

(11)

where (C_ele, u) is the electrolyzer unit rate, f is the power factor, and K_{el, th} is the electrolyzer’s energy requirement. The comparison case assumes that the electrolyzer unit cost is US$368/kWh, which is the goal amount. We believe that the electrolyzer’s annual maintenance and repair costs have a 7-year operating period. Consequently, we must measure the running costs and estimate the per unit expense (US$/kWh) of wind power production of the chosen locations to investigate their economic evaluation. Table 2 presents the components involved in the wind turbine’s evaluation which are the specified power cost (C₁), miscellaneous costs (C₂), construction costs (C₃), operating and repair costs (C₄), inverter costs (C₅), and battery bank costs (C₆).

Table 2 Rated power costs of wind turbine

The PVC can be determined using the following formula.

$$ PVC=I+{C}_2\left(\frac{1+i}{r-1}\right)\left[1-{\left(\frac{1+i}{1+r}\right)}^L\right]-S{\left(\frac{1+i}{1+r}\right)}^L $$

(12)

The total cost (C_T) can be measured as

$$ {C}_{\mathrm{T}}= PVC+{C}_5+{C}_6 $$

(13)

The expense of operating and maintaining a wind turbine is estimated to be 25% of the annual investment cost, whereas scrap is thought to be worth 10% of the annual investment expense (Shahzad et al. 2020). Therefore, the investment expense (I_C) is calculated based on Eq. (14)

$$ {I}_c={C}_{\mathrm{ASPEC}}+{P}_r $$

(14)

where C_ASPEC shows an average cost in per unit kW and P_r determines the rated power cost of a wind turbine (Table 3) (Bangalore and Patriksson 2018).

$$ {C}_{\mathrm{cu}}=\frac{\mathrm{Total}\ \mathrm{cost}}{\mathrm{Annual}\ \mathrm{average}\ \mathrm{yield}} $$

(15)

Table 3 Selected wind turbine specifications

The hydrogen production cost, ${C}_{{\mathrm{H}}_2}$, is a major economic indicator and is calculated based on Eq. (16).

$$ {C}_{{\mathrm{H}}_2}=\frac{C_{\mathrm{W}}+{C}_{\mathrm{ele}}}{M_{{\mathrm{H}}_2}.T} $$

(16)

where C_W and ${M}_{{\mathrm{H}}_2}$ represent the energy cost (US$) and per year green hydrogen production, respectively. Internationally, the constraint on green hydrogen production, mainly through wind energy from electrolysis, has gotten a lot of attention. On the other hand, Pakistan makes use of a small portion of this potential, ignoring the resource’s usability. In the light of the topic above, this evaluation added to the reduction in nonrenewable energy source reliability (Cook et al. 2019). This investigation examined the atmosphere in almost every part of Pakistan while also serving as a condensed study of domestic demand for green wind-produced hydrogen.

$$ Z={\mathit{\max}}_{e,h}\sum \limits_{t\in 0}^T\left({P}_t^e{e}_t^{grid}+{P}_t^h{h}_t\right)\tau $$

(17)

$$ {W}_t={e}_t^{grid}+{e}_t^h,{\forall}_{\mathrm{t}}\in \mathrm{T} $$

(18)

$$ {h}_t=a.{e}_t^h,{\forall}_{\mathrm{t}}\in \mathrm{T} $$

(19)

$$ {h}_t,{e}_t^{grid},{e}_t^h\ge 0\ {\forall}_{\mathrm{t}}\in \mathrm{T} $$

(20)

where ${P}_{\mathrm{t}}^{\mathrm{h}}$ (US$/kgH₂) and ${P}_{\mathrm{t}}^{\mathrm{h}}$ (US$/kWhe) are the negligible hydrogen and consumer power costs, respectively. The h_t (US$/kgH₂/h), hourly hydrogen production, and power supplied from wind energy provided to the national lattice, ht grid, duplicate these costs (kWe). With the set T, t displays a certain period and includes the time interval (60 min). (2) At time t, ${e}_{\mathrm{t}}^{\mathrm{h}}$grid (kWe), the power generated from wind energy is provided to the national grid, ${e}_{\mathrm{t}}^{\mathrm{h}}$ (kWe), and the power spent for renewable hydrogen production at e^th grid (kWe) has been divided (kWe). At time t, limitation (3) depicts the production of green hydrogen using wind energy. According to limitation (4), the option considerations are non-negative genuine numbers and the day-ahead market power price. When the ${P}_{\mathrm{t}}^{\mathrm{h}}$ grid energy is being provided to the KE, hourly hydrogen production, ${P}_{\mathrm{t}}^{\mathrm{h}}$, low hydrogen cost, and ${e}_{\mathrm{t}}^{\mathrm{h}}$ electricity scavenge, the deal is planned. The space-time-yield (STY) measures how much output can be generated per unit of volume and time. This number is used to figure out how much each of the LOHC’s reactor costs. It is determined by Eq. (21).

$$ STY=\frac{n_A{\chi}_A{M}_A}{V_{A0}{t}_R} $$

(21)

with

n_A:

Maximum mole flow of the target product (A) per mole of source material (A₀)

χ_A:

Equilibrium conversion

M_A:

Molar mass

V_A0:

Volume of one mole source material, including solvents

t_R:

Reaction time

Methodology for calculating supply cost of renewable hydrogen

The number of deliveries expected each day would be determined by the hydrogen demand and the truck’s payload:

$$ Required\ deliveries\ per\ da y\ \left({day}^{-1}\right)=\frac{Hydrogen\ demand\ \left( kg\ da{y}^{-1}\right)}{Net\ hydrogen\ payload\ (kg)} $$

(22)

The total trip time will be determined by the following factors which are unloading/loading (drop-off/pick-up) times, transportation size, and average speed:

$$ Total\ trip\ time\ (h)=\frac{2\times one- way\ distance\ (km)}{Average\ driving\ speed\ \left( km\ {h}^{-1}\right)}+ loading\ time\ (h)+ unloading\ time\ (h) $$

(23)

Theoretical maximum number of trips for each truck per day can then be calculated as Eq. (24) below:

$$ \mathit{\operatorname{Max}}\# of\ trip s\ per\ day\ per\ truc k\ \left( da{y}^{-1} truc{k}^{-1}\right)=\frac{24h}{Total\ trip\ time\ (h)} $$

(24)

The required number of trucks was determined based on the number of deliveries required to satisfy the demand, as well as the theoretical potential number of trips per truck would make in 1 day, taking into account the truck availability. The calculation is as in Eq. (25).

$$ Required\# of\ truck s=\frac{Required\ trips\ per\ day}{\mathit{\operatorname{Max}}\# of\ trips\ per\ day\ per\ truck\ast truck\ availability\ \left(\%\right)} $$

(25)

This number was then rounded to the next higher integer. After rounding up, the lowest number of trips per day per truck that satisfies the hydrogen requirement was used in the study, which allowed non-integer amounts. For example, a truck making 0.5 trips per day might deliver any other day. Three times as many trailers as trucks are needed for GH₂ distribution options. In the case of LOHC transport, the trucks will wait until the tanker trailer is unloaded and then filled. As a result, LOHC base distribution necessitates the use of storage tanks. The cost of storage was included in the hydrogen production costs. The appropriate number of trucks and trailers, investment costs (IC), and capital recovery factors (CRF) were used to measure annualized investment costs for truck fleets (IC_ann,trucking), as shown in Eq. (26).

$$ {IC}_{\mathrm{ann},\mathrm{trucking}}=\left(\# of\ trucks\right)\times {CRF}_{\mathrm{truck}}\times {IC}_{\mathrm{truck}}+\left(\# of\ trailers\right)\times {CRF}_{\mathrm{trailer}}\times {IC}_{\mathrm{trailer}} $$

(26)

Operation and maintenance costs, in US$/kg H₂, were calculated from the specified variable (VC) and fixed costs (FC) of trucks and trailers (Tahir and Asim 2018; Gasser 2020), based on Eq. (27)

$$ {SC}_{\mathrm{trucking},\mathrm{O}\&\mathrm{M}}=\frac{\left(\# of\ trucks\right)\times {VC}_{truck}\times \left( annual\ drive\ distance\right)+\left(\# of\ trailers\right)\times \left({IC}_{\mathrm{trailer}}\times {FC}_{\mathrm{trailer}}\right)}{Delivered\ useful\ hydrogen\ per\ year} $$

(27)

Personnel costs for each kilogram of hydrogen delivered depend on the total trip time, the hourly salary of the driver, and the delivered amount of useable hydrogen per truck. The calculation is as Eq. (28)

$$ {SC}_{trucking, personnel}=\frac{\left( total\ trip\ time\right)\times \left( hourly\ salary\right)}{Delivered\ useable\ hydrogen\ per\ truck} $$

(28)

Drive distance, fuel usage, fuel price, and delivered volume of usable hydrogen will all be used to quantify the actual delivery costs due to the truck fuel consumption (Mohsin et al. 2018a; Iqbal et al. 2019b), as per Eq. (29).

$$ {SC}_{trucking, fuel}=\frac{2\times \left( one- way\ distance\right)\times FuelConsumption\times FuelPrice}{Delivered\ useable\ hydrogen\ per\ truck} $$

(29)

The total specific hydrogen delivery cost from trucking then becomes:

$$ {SC}_{\mathrm{trucking}}=\frac{IC_{\mathrm{trucking}}\times {CRF}_{\mathrm{trucking}}}{Delivered\ useful\ hydrogen\ per\ year}+{SC}_{\mathrm{trucking},\mathrm{O}\&\mathrm{M}}+{SC}_{\mathrm{trucking},\mathrm{Fuel}}+{SC}_{\mathrm{trucking},\mathrm{personnel}} $$

(30)

The energy and hydrogen rates were set to determine the worth of variable power and hydrogen supply, whereas the discount rate was determined to result in an NPV of zero at the end of the plant’s lifespan. This discounted rate represents the anticipated return on investment from the construction and operation of various plants.

$$ NPV=\sum \limits_{i=1}^t\frac{ACE_i}{{\left(1+i\right)}^t} $$

(31)

The method used to calculate the expense of CO₂ avoidance is shown in Eq. (31). The levelized cost of energy is represented by LCOE and the actual CO₂ emissions of the plant are represented by E. The plant with CO₂ capture (case 1) was denoted by the subscript CC, while the subscript ref denoted the plant without CO₂ capture (case 1).

Data

The data needed were collected from various sources, which are (1) wind speed data for different cites from the Meteorological Department of Pakistan, (2) cost breakdown structure from the National Renewable Energy Laboratory USA (NREL), and (3) interest rate inflation and other economic indicators from the National Bank of Pakistan (NBP) and State Bank of Pakistan (SBP).

Results and discussion

Green hydrogen production

We used an electrolyzer with a 5-kWh/Nm³ energy intake and a 90 % efficient rectifier in this experiment. The formula for converting hydrogen from normal cubic meters into kilograms is 11.13 Nm³. Table 4 shows the annual hydrogen output at eight different locations selected in this study and their capacity factor (CF).

Table 4 Wind statistics

Ample of wind is required to generate the energy needed for the production of hydrogen. Annually, each car needs approximately 97 kg of hydrogen, as shown in Fig. 1. When the two energy sources were compared, 9.5 kg of hydrogen is equivalent to 25 kg of gasoline. This is because petroleum fuel has a capacity four times than that of hydrogen fuel. Furthermore, Pakistan’s cumulative wind-generated electricity capability is 119,410 MW. Additionally, transportation oil usage may be used to generate energy, alleviating fuel shortages. The total distribution costs for 2.5 MW (1800 kg/day) and 10 MW (7200 kg/day) cases were determined to be 1.0–3.1 US$/kg and 0.7–2.8 US$/kg, respectively. For transport distances of 50–150 km, the LCOE and composite GH₂ were almost similar in their efficiency due to the low venture costs for dehydrogenation reactors, whereas a distance of 300 km favored the LCOE. The cost of delivery using LCOE should not escalate significantly as the distance traveled increases. In any case, delivery using 200 bar steel bottle containers is not the most cost-effective alternative, and the costs rise sharply with distance traveled. The expense for the fleet ranges from €0.3–1.0 million for LCOE shipping, €1.8–7.8 million for steel bottle tanks, and €1.4–7.2 million for composite cylinders.

Figure 1.

Renewable energy and hydrogen production

Economic analysis

The economic analysis was based on the assumptions that construction and operational costs account for 25% of the annual wind turbine expenditure with a lifespan of 20 years, although the installation and investment costs were 5% and 10%, respectively. As a result, at the final supply stage for the provided proposed locations, the average price increased with regard to the consumption intent. Further considerations presumed that the capital expense of sustainable hydrogen production is US$0.027/kg, which covers the direct, secondary, and maintenance costs.

For the ease of comparison, the leveled water supplying rate was estimated to be approximately US$4.1/ton of water. This resulted in the electrolysis system’s capital charging ratio from 0.10 to 0.115 (Fig. 2), while the expense of green hydrogen output for the most effective and optimal device ranges from US$4.02/kgH₂ to US$4.310/kgH₂. Among the investment types, annualized capital investment is the primary determinant of green hydrogen production prices compared to annual expenditures, such as the raw material procurement and plant running costs. The literature on sustainable energy systems showed that the economic burden is imposed by the large capital expenditures. Thus, a practical strategy is needed to boost the economics of renewable energy production, such as adapting, marketing, preparing, timing, and expanding markets and demand. Table 5 presents the results of electricity cost and renewable hydrogen generation. The economic incorporation of hydrogen revealed that the cost of production varied between US$4.90 and US$5.10 per kilogram.

Figure 2.

Capacity factor (CF) and electricity prices

Table 5 Cost of electricity and renewable hydrogen

Since all expenditures are the same, the priority process has little influence on the system’s capital expenditure (CAPEX) as it is just a different scheduling technique. In terms of OPEX, there is a disparity in the volume of hydrogen sold and the costs of transporting hydrogen. However, transportation charges for excess hydrogen orders are not included since they are distributed to third parties who chose to purchase the hydrogen. Because of this distribution, the OPEX and CAPEX for all priority systems are the same. The power rate, which includes the prices for energy from solar parks and grids, is the only factor that varies. The fuel costs in the power-to-H₂ scheme with heat as a target are $260,000 per year, although they have now increased it to $360,000 per year, since heat and hydrogen are purchased from the grid.

In the case of hydrogen, the output prices for heat and hydrogen are always changing. Since the heat system’s reliability has reduced and more energy from the grid is being purchased at a higher price than that from the solar park, the heat price has increased by US$1.1/GJ to US$27.1/GJ. However, with the exact investment costs, the hydrogen demand grew from 90 to 125 tons a year. As a result, the price of hydrogen supply fell from US$5.40 to US$4.60/kg (Fig. 3). When the system prioritized hydrogen, the gross annual costs per household were US$1715/year compared to US$1785/year when heat is prioritized. In terms of yearly costs per home, the favorable impacts on hydrogen production costs balance out the detrimental effects of higher heat production rates. Lower costs can be achieved because more hydrogen can be generated with equal expenditures, resulting in a higher electrolyzer ability factor.

Figure 3.

Capacity factor (CF) and price of H₂

Grid electricity and wind-generated renewable hydrogen prices

The wind-generated renewable electrolysis system’s techno-economic study yielded a LCOH of US$6.22/kgH₂. The costs were split into the wind and electrolyzer sections for the first and second bars, respectively, to demonstrate the ratio of these two parts. The new global movement toward lowering GHG pollution is focused on solid science assertions about the impact of an increasingly evolving atmosphere on natural, social, and economic sustainability. Experts are now warning of the dangers of global climate change caused by GHG pollution from human activities. The CO₂ pollution has increased by 4.2% a year between 1999 and 2004. Additionally, Pakistan is responsible for 0.2% of global CO₂ emissions or around 9.3 tons of CO₂ per human. Pakistan is also among the world’s largest oil producer and has seen a substantial increase in GHG emissions, especially CO₂, as a result of increasing petroleum output and related sales (which accounts for around 95% of export earnings and contributes more than 54% of Pakistan’s GDP). As a result, Pakistan has the potential to enact measures to reduce GHG pollution, for example, emissions exchange scheme. To address the threat of climate change, well-defined emission reduction strategies and environmental legislation are essential.

Pakistan’s foremost contributors to GHG emissions comes from their oil and cement production, which, like most other countries with large increases in GHG emissions, can be linked to the economic and industrial developments. The usage of petroleum products as fuels in many of the refining, industrial, and transportation fields is one of Pakistan’s major causes of air pollution. Their CO₂ is primarily generated through the burning of different fuels in the power generation sector (38%), transportation (20%), industry (8%), and others (34%). Various toxic gases (primarily carbons, hydrocarbons, acid, and nitrogen oxides) are emitted from oil fields and refineries, causing a negative impact on the local residential and marine areas. In 2010, two-thirds of the world’s electricity was generated by burning fossil fuels, with Pakistan emitted approximately 60 million tons (Mt) of CO₂, an increase from 50 million tons (Mt) in 2002. This was primarily due to the rising energy demand. Since the sum of CO₂ pollution per unit of energy differs based on the fuel type (coal, oil, or natural gas), the shift toward higher natural gas consumption should help to reduce CO₂ emissions in the long-run dramatically. The CO₂ emissions were projected to more than double in the coming years as a result of rising energy growth, hitting about 104 Mt in 2030. Over the forecast time frame, the annual average growth in pollution was estimated to be 3.3 %. However, this is smaller than the initial estimate (3.6 % rise in demand) because of the shift to gas-fired power plants.

Table 6 shows that the cost of the electrolyzer is higher than that of the wind device, at US$3.92/kgH₂ and US$2.30/kgH₂, respectively, with a much wider difference if these two plant materials are not maximized. Therefore, more wind power devices were introduced as part of the optimization process to reduce the number of electrolyzer modules, resulting in a power factor rise from 28 to 31%. As a result, the photovoltaic panel’s surface area increased by 4%, while the electrolyzer section’s scale decreased by 11%. Since there is already a demand for economies of scale and a substantial rise in output rate, there is possibility that the electrolyzer’s costs would drop significantly within the next several years. The third bar depicted the total device costs, demonstrating that module costs account for a significant portion of the total.

Table 6 Grid electricity prices

Comparative discussion

In some cases, the purpose of energy security is to protect the poor from fluctuations in commodity prices (Šprajc et al. 2019), whereas others have emphasized the importance of protecting the economy from disruptions in the supply of energy services by increasing the commodity prices during periods of scarcity ( Antoni et al. 2020; Arminen and Menegaki, s; Muller and de Klerk 2020). For some, energy security aims to reliably provide fuel, while the role of nuclear energy is to increase this security (Amin and Bernell 2018; Zhang et al. 2020). The current study’s results revealed that Sindh Province has the potential demand for renewable hydrogen of 454,192,000 kg and that the renewable hydrogen production ability is sufficient. Furthermore, provinces with a strong wind energy capacity, such as the Sindh’s province interior and the coastal areas of Sindh and Baluchistan, also have few options for commissioning a hydrogen production plant. Renewable corridors in Sindh and Baluchistan can be reconciled analytically to ensure renewable hydrogen generation and use ( Adewumi 2020; Liu et al. 2018; Vermeulen et al. 2020). This is because Sindh Province is home to nearly all wind power schemes and its geological characteristics make it ideal for producing green hydrogen for ZEVs and fuel cell electric vehicles.

Energy costs are increasingly making wind-generated renewable hydrogen more appealing. In addition, the impact of K-electric–produced electricity is minor. Wind-generated renewable hydrogen already has a marginal price of US$4.30/kgH₂. As a result, the annual wind-generated renewable hydrogen demand rises with time, owing to improved sales, enabling additional wind power plants to be built and increasing the ability of wind-generated renewable hydrogen output (El Khatib and Galiana 2018; Khan et al. 2018). Hydrogen could also be supplied by cryogenic tanker trucks or liquefied and transported by pipelines. Although pipelines are only cost-efficient for vast quantities or short lengths, they are seldom used to maximize the efficiency of hydrogen by-product. Due to the substantially complex cargoes (4000–4500 kg), liquefaction will allow renewable generated hydrogen to be trucked more effectively over long distances but is both capital- and energy-intensive. Besides, boil-off damages are often caused by the shipping and handling of liquid hydrogen (Roddis et al. 2018). Owing to the immaturity of the process, the investment costs for dehydrogenation and hydrogenation reactors are somewhat unpredictable. For a “large-scale” green hydrogen production, Krejčí and Stoklasa (2018) reported that for a large-scale green hydrogen production, the costs were between US$40 and US$260/kWH₂. However, the basic costs for hydrogenation and dehydrogenation reactors were between US$252 and US$368/kWH₂. These numbers show that the cost estimates for hydrogen production vary greatly.

In addition, there is considerable inconsistency in the prices of hydrogenation and dehydrogenation reactors, as mentioned earlier. Teichmann, for example, calculated the hydrogenation reactor costs to be slightly higher than the dehydrogenation reactor costs, while it is estimated the reactor costs to be almost similar. Other researchers such as Al Garni and Awasthi (2017) also thought that the dehydrogenation reactor was more costly, although Reu had different thoughts. If Pakistan implements the green hydrogen power production, they might reduce its crude oil demand by 600 billion barrels a day. In this sense, it will be necessary to reduce the existing CO₂ emissions of 166,298,450 tons. Results have showed the cost of CO₂ emissions at different constrained prices, which could be affordable compared to the cost of ecological theft. Since the yield of green hydrogen is dependent on the nature of usable wind, which differs and is challenging to forecast, using a greater degree of wind output poses a suspension problem. The electricity market faces considerable inconsistency due to this variation, as it becomes difficult to balance the supply and demand. In the case of traditional power terminals, shifting demand levels will render the market power costs extremely volatile, posing additional difficulties for businesses who depend on transmitting it (Maleki et al. 2017; Valasai et al. 2017).

Conclusion and policy implication

The current study measured the wind power potential and economic viability of wind-generated renewable hydrogen to initiate the feasibility of clean fuel. The study’s outcomes can be generalized for policymaking in developing countries such as Pakistan, which is economically and environmentally vulnerable. Different electrolyzer systems exist to generate effective hydrogen via the electrolysis phase. When the minimum price of hydrogen exceeds US$2.99/kgH₂, green hydrogen demand rises as well. In Pakistan’s energy sector, however, it is commercially beneficial since the marginal price of sustainable hydrogen is US$3.92/kgH₂. Furthermore, due to the efficiencies of the hydrogen conversion mechanism, wind energy could generate approximately 0.85 billion kilogram of hydrogen in Pakistan, which could meet the country’s 22% demand for hydrogen.

The findings showed that the marginal prices of renewable hydrogen, between US$1/kgH₂ and US$4/kgH₂, have a considerable impact on the annual hydrogen demand which was a significant rise in renewable hydrogen production. Furthermore, lower renewable hydrogen prices (e.g., US$2/kg) have a relative impact on renewable hydrogen demand. Annual wind-generated sustainable hydrogen output is dependent. The performance of an energy conversion electrolyzer device will have a significant impact on the amount of renewable hydrogen generated by wind.

In both the public and private sectors, the main players in the supply chain of Pakistan’s multi-tiered electricity are the Independent Power Producers (IPPs). WAPDA has four GENCO distribution entities since 2012 due to consolidation, with three Rental Power Projects (RPPs) to choose from. Pakistan’s gross installed power generating capacity will exceed 3.4 GW in 2020, compared to a requirement of 2.5 GW from primary customers. However, with only 2.2 GW energy being supplied during the peak hours, it would be difficult to substitute the 3000 MW deficit difference. As a result of machine inefficiency, the NTDC and KEL had a 17.53% and 25.30% line losses, respectively. As a consequence, there is a significant difference between production and demand. Furthermore, most hydroelectric plants are operating at 50% potential and are affected by seasonal water supply. This causes the operational capability of thermal plants that contributed more than 60% of the overall power production to be only at 65%. Notably, increasing generating capability and relying too heavily on hydrocarbon supplies did not help mitigate energy shortages where usable resources are underutilized or misused. Increasing the country’s power generating capacity by constructing new plants is an unworkable option for increased availability. On the other hand, repairing improperly run generation plants and dysfunctional transmission and dispatch networks will accomplish the same goal.

Distribution losses ranged from 9.47 to 33.40%, and no DISCOs could hit NEPRA’s loss goals, with some seeing an improvement over the previous year. Another issue is the lack of a long-term, organized, and integrated policymaking, as shown by the fact that the programs just started. There were also times whereby the schemes implemented were found to be infeasible in the middle of the project. Additionally, due to geopolitics, despite its significant hydropower capacity, it was not given any priority. Besides, no technological adaptation abused local capital and after signing the memorandum of understanding (MOU) for thermal plants, the China Pakistan Economic Corridor is now responsible for all projects.

The Pakistani government, on the other hand, wants to promote and build wind-generated electricity and has suggested many locations. This is because Pakistan will meet its national demand and export clean electricity by converting its power system to wind and solar energy. There are several pathways for hydrogen development, including thermal and renewable hydrogen, which are the most widely utilized process due to their reliability and low cost. In comparison, hydrogen production using fossil fuels generates hazardous gases (e.g., GHGs) during the manufacturing phase.