Readiness of Malaysian PV System to Utilize Energy Storage System with Second-Life Electric Vehicle Batteries

Abstract

The potential of renewable energy sources to lower greenhouse gas emissions and lessen our reliance on fossil fuels has accelerated their integration globally, and especially that of solar photovoltaic (PV) systems. Malaysia has shown great progress in the adoption of photovoltaic systems thanks to its plentiful solar resources. On the other hand, energy storage systems (ESSs) are becoming more and more necessary in order to guarantee grid stability and fully realize the benefits of PV systems. This study attempts to assess the current condition of PV installations in Malaysia with an emphasis on their economic feasibility, regulatory compliance, technological capabilities, and compatibility with various energy storage technologies. Malaysian photovoltaic (PV) systems’ readiness to integrate energy storage systems (ESSs) using second-life electric vehicle batteries (SLEVBs) is examined in this article. Integrating PV systems with SLEVBs in residential ESSs shows economic viability, with a 15-year payback and 25% return on investment (ROI). Therefore, for every 1 MW of installed PV capacity, with ESS integration it is estimated to reduce approximately 3504 metric tons of CO₂ emissions annually in Malaysia. The homeowner benefits from large electricity bill savings, net metering revenue, and various incentives or financing alternatives that make the project financially attractive despite the extended payback time. Energy storage solutions are needed to improve grid stability, energy usage, and solar power generation in Malaysia as renewable energy adoption increases. Reusing retired EV batteries for stationary storage could solve environmental and economic issues. This study examines the feasibility, regulatory frameworks, and economic viability of combining second-life EV batteries with PV installations in Malaysia.

1. Introduction

The world’s transition to sustainable energy has transformed countries’ energy landscapes to reduce their carbon footprints and increase their energy resilience [1]. Malaysia has prioritized photovoltaic (PV) system deployment in its renewable energy portfolio for sustainable development. However, inconsistent solar power generation reduces grid stability, necessitating a strategic assessment of Malaysian PV systems’ readiness for seamless energy storage system (ESS) integration.

Thus, the Malaysian government is shifting towards a greener, cheaper energy source [2]. The 2001 fuel diversification strategy (FDP) aims to expand renewable energy technology, as a more environmentally friendly alternative to fossil fuels, in the grid system [3]. The 2022 National Energy Policy (NEP 2022) aims to provide 18% of the country’s primary energy from renewable sources (RESs). This strategy improves energy sector planning to ensure electricity supply security and promote sustainable socio-economic development [4]. Many efforts have been implemented under NEP 2022 to encourage industries and communities to use renewable energy. In addition, the government is offering incentives, refunds, and grants for solar, biomass, and small hydro installations. Renewable energy sources (RESs) in the grid system would support grid demand, frequency responses, and energy security [5]. The National Electricity Utility is leading the deployment of energy storage in Malaysia, focusing on environmental, social, and governance issues as key growth areas in the domestic power industry [6]. This shows the nation’s dedication to a cleaner, more sustainable energy source that benefits society and the environment.

Malaysia has increasingly adopted renewable energy sources, particularly photovoltaic (PV) systems, to diversify its energy mix and lessen its dependence on fossil fuels. However, intermittent solar power generation threatens system stability and reliability [7]. ESSs can solve this problem by storing surplus energy during peak generation for later use, creating a more balanced and resilient system [8]. The rise of electric vehicles (EVs) and the global shift towards sustainable transportation have created a surplus of retired EV batteries with significant capacity. Reusing second-life electric vehicle batteries (SLBs) for stationary storage applications can reduce waste, repurpose assets, and improve energy storage sustainability [9]. The Peninsular Malaysia Generation Development Plan 2020 called for Malaysia to adopt a 500 MW ESS, which has positively impacted grid expansion efforts to sustain, control, and give electric utilities and renewable grid operators flexibility in managing energy flows going forward [10]. In order to decrease the requirement for traditional coal power generation from 37% in 2021 to 22% in 2030, there will be an expansion in RE capacity, particularly in terms of solar PV, under the following development plan [10]. Considering the anticipated withdrawal of resources from the distribution network, it is anticipated that there will be an increase in energy demand valued at 0.6% to 1.8% between 2021 and 2030 based on the recent effects of the pandemic [10]. Based on the results of the development plan, it is projected that in 2021 and 2030, the grid system’s yearly system costs will rise from MYR 28.79 billion to MYR 41.96 billion. Existing coal power plants could be replaced or optimized through the mixed integration of RE and ESSs to handle future increases in energy demand while preserving the stability of the grid system. All things considered, this would lower the price needed to buy coal for electricity production and the yearly maintenance of facilities. The yearly system cost may therefore be further reduced in the years to come due to the equipment that is already accessible within the grid system and the falling cost of RESs and ESSs. Nonetheless, periodic and more comprehensive research is necessary to monitor the projected costs in the energy industry.

The readiness of Malaysian PV systems to integrate ESSs using SLBs is examined in this paper. This study examines SLB integration’s potential to improve PV system performance and meet Malaysia’s renewable energy goals by examining its technical feasibility, regulatory frameworks, and economic viability. It also seeks to identify SLBs’ integration potential and obstacles to help policymakers, industry stakeholders, and investors transition to a more sustainable energy future in Malaysia. We hope to illuminate the revolutionary potential of integrating PV systems with SLB-based ESSs to create a more robust, efficient, and environmentally sustainable energy ecosystem in Malaysia. The rest of the paper is organized as follows: Section 2 discusses the landscape of the Malaysian PV system and energy storage systems (ESSs). Technologies for ESSs are described in Section 3. The readiness assessment of ESSs is shown in Section 4. The policy and regulatory framework and case studies are shown in Section 5 and Section 6, respectively. In conclusion, final observations and recommendations for future work are given in Section 7.

2. Landscape of Malaysian PV System and Energy Storage Systems (ESSs)

The landscape of Malaysia’s PV system shows its growing renewable energy focus. Malaysia has pioneered solar photovoltaic systems due to its abundant sunshine and commitment to sustainability. Malaysia’s PV system makes it a regional leader in solar energy adoption due to advantageous conditions, supportive legislation, and continual solar technology breakthroughs.

2.1. Current Status of Malaysian PV System

The landscape of Malaysia’s solar photovoltaic (PV) system is showing a significant increase. Malaysia leads in renewable energy due to its warm environment and devotion to sustainability. Through various schemes and incentives, the Malaysian government has aggressively promoted solar PV technology [7]. The Large-Scale Solar (LSS) initiative for utility-scale solar projects and the Net Energy Metering (NEM) program allow users to generate and sell electricity back to the grid. These efforts stimulate residential, commercial, and industrial PV installations. Solar photovoltaic systems are gaining popularity among residential and commercial customers as they reduce carbon emissions and electricity expenses. Malaysia’s photovoltaic capacity has grown due to large-scale solar projects, often through the LSS program [11]. Typically, these projects entail building solar farms, which produce electricity that is connected to the national grid. With 198.87 MW, Perak has the largest planned LSS capacity. Kedah (194.89 MW), Negeri Sembilan (121 MW), Pahang (109.92 MW), and Selangor (87.94 MW) are the states with the next largest capacity [7]. By 2020, Melaka, with the third largest average solar irradiance, will have an LSS capacity of only 6.8 MW, while Perlis, with the sixth largest average solar irradiance, will produce only 33 MW. Based on Sabah’s projected 72.5 MW LSS capacity, a feasibility study of its storage project should be conducted independently. The large-scale solar projects in Malaysia are shown in Figure 1.

Malaysia has invested in research and development as well as the production of solar PV systems. The nation has established a photovoltaic manufacturing industry, generating solar panels and their components for both local and foreign markets. Universities and research centers have also been active in PV-related innovation and research. PV system grid integration has been a priority, with initiatives implemented to improve the grid’s capacity and dependability to support solar energy [12]. For the electrical grid to remain stable and to maximize the use of solar energy, grid-connected PV installations are necessary.

In addition, Malaysia has emerged as a significant solar panel exporter, adding to the world’s PV technology supply. The nation’s economy is strengthened by this export sector, which also solidifies Malaysia’s standing as a major participant in the global PV market. It is now simpler for individuals and companies to invest in solar technology thanks to the increased availability of investment and financing options for photovoltaic projects. PV adoption has been aided by financial institutions, government-backed funds, and green financing initiatives.

The government’s goal is to have 31% of the nation’s energy needs satisfied by renewable energy by 2025, 35% by 2030, 40% by 2035, 50% by 2040, and 65% by 2045, as stated in the Malaysia Renewable Energy Roadmap (MyRER) [13]. The deployment of solar PV systems in Malaysia is still moving in a positive direction. By 2050, their installed capacity is expected to surpass 70% due to ongoing technological advancements, declining costs, and increased public awareness. Apricum, a consulting firm with headquarters in Berlin, has projected an additional 1098 MW of solar power by 2025 and 2414 MW by 2035 [7]. Peak demand is 3950 MW in Sabah and Sarawak and 17,788 MW in Peninsular Malaysia. Peninsular Malaysia generates and makes up to about 137.5 GW of solar power, or 51.11%; Sabah and its environs contribute 99.4 GW, or 36.95%; and Sarawak and the surrounding provinces contribute 32.1 GW, or 11.93%, from their solar PV systems. According to the Planned Energy Scenario (PES), where energy demand is predicted to grow by 2.0% annually on average, Malaysia’s final energy consumption will double by 2050. With a total capacity of 83 GW in the Transforming Energy Scenario (TES) and 153 GW in the 1.5 °C Scenario (1.5-S) by 2050, solar PV will play a significant role in the energy transition. Renewable energy will account for at least 89% of all electricity generation, up from 16% currently [14]. Figure 2 depicts the renewable energy road map.

The government’s various initiatives, the rise in installed capacity, and the growing interest from residential, commercial, and industrial consumers have all contributed to Malaysia’s notable advancement in the adoption of solar PV technology. Malaysia is positioned as a major player in the shift to clean and sustainable energy sources due to the country’s dedication to renewable energy and the ongoing growth of its photovoltaic industry [15]. But there are still problems with intermittency, grid stability, and integrating energy storage systems; more work is required to resolve these problems in order to provide more dependable and sustainable energy in the future.

Table 1. Research summary of the readiness of Malaysian PV systems to use ESSs.

Research Summary	Research Gaps	Future Work	Reference
Assessment of current PV installations and their integration with ESSs.	Lack of detailed regional data on PV system performance.	Conduct regional performance assessments of PV systems.	[16]
Policy evaluation for PV and ESS deployment.	Insufficient analysis of policy impact on ESS adoption.	Study long-term impact of current policies on ESS uptake.	[17]
Technical feasibility of integrating ESSs with PV systems in urban areas.	Limited case studies in urban settings.	Develop and analyze urban-specific case studies.	[18]
Economic viability of PV-ESS in Malaysia.	Incomplete financial models considering local factors.	Develop comprehensive financial models for Malaysian context.	[18]
Environmental impact assessment of PV-ESS integration.	Lack of comprehensive lifecycle analyses.	Perform detailed lifecycle environmental impact studies.	[19]
Behavioral analysis of EV users and their impact on ESS deployment.	Limited user behavior studies specific to Malaysia.	Conduct surveys and studies on Malaysian EV user behavior.	[20]
Technological advancements in PV systems and ESSs.	Slow adoption of latest technologies.	Promote adoption and adaptation of advanced technologies.	[17]
Grid stability and integration of PV-ESSs.	Insufficient grid impact studies.	Study the impact of large-scale PV-ESS integration on grid stability.	[21]
Business models for PV-ESS integration.	Limited exploration of innovative business models.	Develop and test new business models for PV-ESSs.	[22]
Role of communication and information technology in PV-ESSs.	Limited integration of advanced IT solutions.	Explore IT solutions for efficient PV-ESS management.	[23]
Comparative analysis of different ESS technologies.	Lack of comprehensive comparative studies.	Conduct detailed comparisons of ESS technologies.	[24]
Impact of climate conditions on PV-ESS performance.	Limited studies on climate-specific impacts.	Investigate the effects of Malaysian climate on PV-ESSs.	[25]
Infrastructure readiness for PV-ESSs.	Incomplete assessment of existing infrastructure.	Evaluate and upgrade infrastructure for PV-ESS integration.	[17]
Case studies of successful PV-ESS projects.	Few documented successful case studies in Malaysia.	Document and analyze successful PV-ESS projects.	[26]
Policy recommendations for enhancing PV-ESS adoption.	Lack of comprehensive policy frameworks.	Develop and propose new policy frameworks.	[24]
Cost–benefit analysis of PV-ESSs.	Limited comprehensive cost–benefit analyses.	Perform detailed cost–benefit analyses for different scenarios.	[18]
Technological challenges in PV-ESS integration.	Insufficient focus on technical barriers.	Identify and address technical challenges.	[21]
Sustainability of second-life EV batteries in ESSs.	Limited research on second-life batteries’ sustainability.	Study the long-term sustainability of second-life EV batteries.	[27]
Market potential of PV-ESSs.	Lack of market analysis specific to Malaysia.	Conduct market potential studies for PV-ESSs.	[27]

summarizes research findings related to the readiness of Malaysian PV systems to utilize ESSs.

2.2. Advantages of the Integration of Energy Storage Systems (ESSs) with Photovoltaic (PV) Systems

There are several benefits to integrating energy storage systems (ESS) with photovoltaic (PV) systems that improve the sustainability, dependability, and efficiency of producing renewable energy. Energy storage systems (ESSs) facilitate the accumulation of surplus solar energy produced during periods of heightened sunlight intensity, thereby empowering homes and businesses to harness stored energy during periods of diminished solar irradiance or increased energy requirements. This approach optimizes the utilization of solar energy for personal consumption and diminishes the dependence on conventional grid electricity, resulting in financial benefits and enhanced energy autonomy [15].

Table 2. Advantages of integrating energy storage systems (ESSs) with photovoltaic (PV) systems.

Advantage	Description
Increased Energy Self-Consumption	Energy storage allows PV system owners to store excess energy generated during sunny periods for later use, increasing self-consumption and reducing reliance on the grid [28].
Grid Independence	PV-ESSs can operate independently of the grid, providing power during grid outages or in remote areas where grid connection is unavailable or unreliable.
Peak Demand Shaving	Energy storage enables PV system owners to reduce peak demand charges by discharging stored energy during periods of high electricity demand, thereby lowering their overall electricity costs.
Enhanced Grid Stability	ESS integration stabilizes the grid by smoothing PV power production fluctuations and minimizing voltage swings from intermittent renewable energy sources [29].
Time-of-Use Tariff Optimization	ESS integration lets PV system owners store excess energy while power costs are low and discharge it during peak demand, saving money.
Improved Power Quality	In places with significant PV penetration, ESSs can provide reactive power and regulate voltage, enhancing power quality and grid dependability.
Renewable Energy Integration	PV-ESS integration provides dispatchable power and balancing services to integrate renewable energy sources into the grid, improving grid reliability and flexibility [30].
Provision of Ancillary Services	Integrating ESSs with PV systems allows for frequency regulation, spinning reserves, and voltage support, improving grid stability and reliability.
Load-Shifting for Tariff Arbitrage	PV-ESSs let consumers use time-of-use tariffs and reduce power bills by shifting energy usage from peak to off-peak.
Environmental Benefits	ESSs’ integration with PV systems delivers clean, renewable energy, reducing greenhouse gas emissions and improving sustainability [31].

shows the advantages of integrating energy storage systems (ESSs) with photovoltaic (PV) systems.

2.3. Challenges in the Integration of Energy Storage Systems (ESSs) with Photovoltaic (PV) Systems

PV installations are becoming more popular; however, their intermittent nature causes energy supply and demand imbalances. Due to intermittency, grid-level solutions like energy storage systems must balance supply and demand. Energy storage systems (ESSs) and photovoltaic (PV) systems in Malaysia have integration issues. Installing energy storage devices is difficult, although PV use is rising [32]. These issues may reduce PV-ESSs’ efficiency, cost, and reliability. Installing and buying lithium-ion batteries is expensive [33]. The high initial expenses of ESSs, especially when combined with those of PV installation, may deter businesses and people from investing. These cost barriers and financial incentives must be addressed to increase adoption.

Technically integrating ESS with PV systems is difficult. To capture and store energy effectively, compatibility, system sizing, and electrical compatibility must be addressed [34]. Installation and maintenance must be carried out properly for the best benefits. Energy storage systems (ESSs) use lithium-ion batteries, which have a limited lifespan and charge–discharge cycles. Over time, battery degradation reduces their capacity and performance and increases replacement costs. ESSs’ battery management must be improved to extend their lifespan. For grid–ESS integration, regulations and criteria must be followed. To ensure safe and successful operation, grid connection and ESS operation rules are needed. Regulations can complicate or delay ESS projects. Due to intermittent solar power output, an ESS is needed to store excess energy during sunny days and supply electricity at night or on gloomy days. Energy production and consumption must be balanced, and proper sizing and control are needed to ensure power supply [35]. Larger installations like utility-scale photovoltaic farms can make scaling ESSs difficult. To balance energy supply and demand, an ESS’s capacity requires careful engineering, planning, and funding.

Consider how ESS technologies may influence the environment, especially lithium-ion battery disposal. Recycling and disposal must be efficient to lessen energy systems’ environmental impact [36]. Consumers’ and enterprises’ ignorance of ESS technology may hinder its adoption. Public education and awareness campaigns are needed to promote ESS’s benefits and practicality in PV systems. Integrating ESSs with PV systems is hard to assess economically. It involves calculating cost–benefit analysis results, revenue streams (such grid services), and the ROI. Residential and commercial users may find this difficult. The safety and security of ESSs are essential. Maintenance and safety must be implemented to prevent accidents and unauthorized access [37]. The challenges in the integration of energy storage systems (ESSs) with photovoltaic (PV) systems are shown in

Table 3. Challenges in the integration of energy storage systems (ESSs) with photovoltaic (PV) systems.

Challenge	Solution	Description
Intermittency and Variability	Advanced Forecasting Algorithms	Use advanced algorithms and machine learning to improve solar PV generation forecasts, which will help manage variability and integrate renewable energy into the grid more effectively.
Energy Imbalance	Demand–Response Programs	Implement programs to shift energy usage during peak times, balancing load demands and energy supply, enhancing grid stability, and reducing the need for additional power generation.
System Sizing and Scalability	Capacity Optimization Models	Utilize models to determine the optimal size of energy storage systems, ensuring cost efficiency and scalability for future expansion and changing energy needs.
Battery Degradation and Lifetime	Lifecycle Assessment	Conduct assessments to monitor and predict battery performance, helping plan for timely replacements and improve system reliability and longevity.
Complex Energy Management	Smart Energy Management Systems	Implement systems that use advanced software and IoT devices to efficiently manage and distribute energy, balancing supply and demand and optimizing energy usage.
Costs and Economic Viability	Cost–Benefit Analysis	Perform analyses to assess long-term savings and ROI, evaluating installation, operational, and maintenance costs to justify investments and attract funding.
Regulations and Grid Interconnection	Policy Impact Analysis	Analyze and adapt policies to facilitate grid interconnection, ensuring compliance with regulations and promoting renewable energy adoption and infrastructure resilience.
Safety and Environmental Concerns	Safety Standards and Environmental Impact Assessments	Ensure compliance with safety standards and conduct environmental impact assessments to mitigate risks, protect the environment, and gain regulatory approval.
Technological Compatibility	Standardization and Integration Testing	Develop standardized testing protocols to ensure compatibility with existing and future technologies, reducing technical issues and ensuring seamless operation.
Education and Awareness	Awareness Campaigns	Increase awareness through targeted campaigns, highlighting the benefits and best practices of energy storage systems to drive adoption and support the transition to sustainable energy solutions.

.

Government authorities, industry stakeholders, and researchers must collaborate to develop clear policies, standards, and creative solutions to integrate energy storage systems with PV systems in Malaysia. These challenges must be overcome to maximize renewable energy and ensure a reliable and sustainable energy future.

3. Technologies for Energy Storage Systems

The demand for flexibility, sustainability, and dependability in the ever-changing energy market has made energy storage systems (ESSs) more popular [37]. These systems—like the power industry’s “batteries”—are crucial to transforming energy production, usage, and distribution. Their operation relies on modifying our sense of time to gather energy when it is abundant, store it efficiently, and release it when needed. The integration of renewable energy sources presents hurdles; therefore, ESSs are crucial [38]. Solar and wind electricity are renewable and environmentally friendly; however, their generating patterns vary. An ESS separates energy generation from consumption, balancing sustainability and dependability. This intricate energy–time dance is not restricted to grid applications. Energy storage devices can power electric vehicles, strengthen microgrids in remote places, and provide power to critical infrastructure [39].

Table 4. Research summary of energy storage technology.

Research Summary	Research Gaps	Future Work	Reference
Development of high-density lithium-ion batteries.	Limited cycle life and safety concerns.	Improve safety features and enhance cycle life through new materials.	[40]
Exploration of solid-state batteries.	High production costs and scalability issues.	Reduce manufacturing costs and improve scalability.	[41]
Evaluation of flow batteries for grid storage.	Low energy density and high maintenance.	Increase energy density and reduce maintenance requirements.	[42]
Use of second-life EV batteries in ESSs.	Limited data on performance and degradation.	Conduct long-term performance and degradation studies.	[43]
Integration of supercapacitors with batteries.	Challenges in balancing energy and power density.	Optimize hybrid systems for better energy and power management.	[44]
Advanced battery management systems (BMSs).	Inadequate predictive maintenance capabilities.	Develop more accurate predictive maintenance algorithms.	[45]
Role of ESSs in renewable energy integration.	Inconsistent performance under varying environmental conditions.	Test and adapt ESS technologies to different climatic conditions.	[27]
Economic analysis of ESS deployment.	Insufficient real-world cost–benefit analyses.	Conduct comprehensive economic assessments including externalities.	[27]
Environmental impact of ESS technologies.	Limited lifecycle impact studies.	Perform detailed lifecycle environmental assessments.	[19]
Policy frameworks for ESS adoption.	Lack of supportive policies and incentives.	Develop and implement effective policies and incentives for ESS.	[24]

summarizes research findings, gaps, and future work related to energy storage technology.

The importance of ESS is only going to increase as more people around the world embrace the electrification of transport, the expansion of our renewable energy capacity, and the necessity of building resilient energy infrastructures. Due to the intermittent nature of solar power generation, energy storage systems are essential to photovoltaic (PV) applications. Several kinds of energy storage systems are frequently used with photovoltaic systems, shown in Figure 3.

3.1. Batteries for Energy Storage Systems

In the current energy landscape, battery energy storage systems (BESSs) are cutting-edge technologies that are intended to store electrical energy in a chemical form. They offer a vital solution for balancing supply and demand. These systems are essential for improving grid stability, incorporating renewable energy sources, and resolving the intermittency issues brought about by energy sources such as wind and solar power. The applications of BESS include backup power and grid-level storage, which help electrify transportation and pave the way for a more resilient and sustainable energy future [5]. BESS has the potential to completely change how we produce, distribute, and use electricity as technology develops, making it more affordable, effective, and environmentally friendly. See

Table 5. Different types of battery energy storage systems (BESSs), along with their advantages and disadvantages.

Battery Type	Advantages	Disadvantages
Lithium-Ion [46]	High energy density: Provides more energy storage capacity in a smaller footprint. Long cycle life: Capable of thousands of charge–discharge cycles. Rapid charging: Allows for quick recharging times. Low self-discharge rate: Retains charge for longer periods.	High cost: Lithium-ion batteries are relatively expensive compared to other battery types. Safety concerns: Risk of thermal runaway and fire. Limited lifespan: Degradation over time, especially at high temperatures. Environmental impact: Concerns regarding mining and disposal.
Lead-Acid [47]	Low cost: Relatively inexpensive compared to other battery technologies. Mature technology: Well-established and widely understood. Recyclable: Lead-acid batteries can be recycled. Wide operating temperature range: Suitable for various environments.	Low energy density: Provides lower energy storage capacity per unit weight or volume. Limited cycle life: Fewer charge–discharge cycles compared to some other battery types. Maintenance requirements: Requires periodic maintenance, including watering and cleaning. Environmental concerns: Lead and sulfuric acid components pose environmental risks.
Flow Batteries [48]	Scalability: Easily scalable to meet different energy storage requirements. Long cycle life: Can endure numerous charge–discharge cycles with minimal degradation. Safety: Non-flammable electrolytes enhance safety. Decoupled power and energy: Offers flexibility in design.	Complex design: Flow batteries can be more complex and require additional components compared to some other battery types. Lower energy density: Typically lower energy density compared to lithium-ion batteries. Limited temperature range: Performance may degrade at extreme temperatures. Cost: Higher initial cost compared to some other battery technologies.
Sodium–Sulfur [49]	High energy density: Offers high energy storage capacity. High efficiency: Provides efficient charge–discharge cycles. Long cycle life: Capable of enduring numerous cycles without significant degradation. Suitable for high-temperature environments: Performs well in elevated temperatures.	High operating temperature: Requires high operating temperatures to maintain functionality, limiting deployment options. Safety concerns: Sodium and sulfur components can be hazardous. Limited applications: Primarily suited for utility-scale applications, less practical for smaller-scale deployments. Cost: High initial cost and maintenance expenses.
Nickel–Cadmium [50]	Long cycle life: Can withstand thousands of charge–discharge cycles. High discharge rates: Suitable for applications requiring high power output. Wide operating temperature range: Performs well in various environmental conditions. Low maintenance: Requires minimal maintenance.	Toxicity: Cadmium component poses environmental and health risks. Limited energy density: Lower energy density compared to some newer battery technologies. Memory effect: Susceptible to memory effect if not properly maintained. High self-discharge rate: May lose charge relatively quickly when not in use.
Nickel–Metal Hydride [51]	High energy density: Provides a good balance between energy storage capacity and size. Environmentally friendly: Contains no toxic metals like cadmium or lead. Long cycle life: Capable of enduring hundreds to thousands of charge–discharge cycles. Low self-discharge rate: Retains charge for extended periods.	Limited temperature range: Performance may degrade at extreme temperatures. Limited lifespan: Degradation over time, especially with frequent cycling. Memory effect: Susceptible to memory effect, although less so than nickel–cadmium batteries. High self-discharge rate: May lose charge relatively quickly when not in use.

for different types of battery energy storage systems (BESSs), along with their advantages and disadvantages.

3.2. Second-Life Electric Vehicle Batteries for Energy Storage Systems

With the rapid growth of electric vehicles (EVs), the issue of the end-of-life management of EV batteries has become increasingly pertinent. A promising solution gaining traction is the repurposing of used EV batteries for a second life in energy storage systems (ESSs). This review explores the opportunities and challenges associated with this innovative and sustainable approach.

3.2.1. Opportunities

Reusing EV batteries is cheaper and more environmentally friendly than making new ones [52]. This circular economy model reduces waste and battery production’s environmental impact. A second life greatly extends EV battery life. When used for stationary energy storage, an SLEVB can retain 70% to 90% of its original capacity [53]. An EV battery that had a capacity of 40 kWh when new may now have 28 kWh to 36 kWh. Although these batteries may no longer fulfill vehicle standards, they generally retain a significant capacity for stationary storage, saving resources. Energy storage systems can be deployed quickly using EV batteries. These batteries can adapt to rising energy storage needs and grid stability issues due to their existing infrastructure. Second-life EV batteries are scalable and appropriate for many applications. Repurposed batteries provide customized storage capacity from the home to grid level [54]. Reusing EV lithium-ion batteries is a proven technology. Our expertise in handling these batteries for automotive usage ensures their efficient and reliable performance in stationary applications.

The integration of photovoltaic (PV) systems with energy storage systems (ESSs) using second-life electric vehicle batteries is a novel Malaysian residential energy solution. Photovoltaic (PV) panels on rooftops allow homeowners to create clean, renewable electricity for their households [55]. Energy storage systems (ESSs) using Solar Light Energy Storage (SLEVB) improve photovoltaic (PV) system efficiency and reliability by storing surplus energy for use during periods of low solar irradiation or high energy needs [56]. This lets homes maximize their solar energy utilization, reduce power grid dependence, and reduce fluctuating electricity costs [57,58]. Second-life electric vehicle (EV) batteries for stationary energy storage extend battery longevity and reduce waste, improving sustainability [59]. Overall, integrating Malaysian household PV systems with ESSs utilizing SLEVBs is a cost-effective and environmentally responsible way to generate and consume sustainable energy.

Integrating a photovoltaic (PV) system with an energy storage system (ESS) involves several mathematical equations to describe their energy flow, storage capacity, and efficiency. Below are the key equations and their descriptions.

The energy generated by a PV system can be calculated using the following equation:

$$E_{PV}=P_{PV}\times H\times {\eta }_{PV}$$

(1)

where $E_{PV}$ is the energy generated by the PV system (kWh), $P_{PV}$ is the rated power of the PV system (kW), $H$ is the solar insolation or peak sun hours (hours), and ${\eta }_{PV}$ is the efficiency of the PV system (unitless). Equation (1) is used to calculate the total energy produced by the PV system based on its power rating, the solar insolation it receives, and its efficiency.

The usable storage capacity of a battery is given by

$$C_{usable}=C_{nominal}\times DoD$$

(2)

where $C_{usable}$ is the usable storage capacity (kWh), $C_{nominal}$ is the nominal storage capacity of the battery (kWh), and $DoD$ is depth of discharge (typically a percentage). Equation (2) determines the amount of energy that can be stored and utilized from the battery, considering its depth of discharge.

The energy balance equation ensures that the energy generated, stored, and consumed is accounted for:

$$E_{balance}=E_{PV}+E_{ESS,in}-E_{load}-E_{Ess,out}$$

(3)

where $E_{balance}$ is the net energy balance (kWh), $E_{ESS,in}$is the energy charged into the ESS (kWh), $E_{load}$ is the energy consumed by the load (kWh), and $E_{Ess,out}$ is the energy discharged from the ESS (kWh).

The energy stored in the ESS over time can be expressed as

$$E_{ESS}\left(t\right)=E_{Ess}\left(t-1\right)+E_{Ess,in}\left(t\right)-E_{Ess,out}\left(t\right)$$

(4)

where $E_{ESS}\left(t\right)$ is the energy stored in the ESS at time $t$(kWh), $E_{Ess}\left(t-1\right)$ is the energy stored in the ESS at time $t-1$ (kWh), $E_{Ess,in}\left(t\right)$ is the energy charged into the ESS at time $t$ (kWh), and $E_{Ess,out}\left(t\right)$ is the energy discharged from the ESS at time $t$ (kWh).

The round-trip efficiency of the ESS is given by

$${\eta }_{ESS}={\eta }_{charge}\times {\eta }_{discharge}$$

(5)

where ${\eta }_{ESS}$is the round-trip efficiency of the ESS (unitless), ${\eta }_{charge}$ is the charging efficiency of the ESS (unitless), and ${\eta }_{discharge}$ is the discharging efficiency of the ESS (unitless).

The total energy available for use from the PV system and ESS is

$$E_{total}=E_{PV}\times {\eta }_{PV}+(C_{usable}\times {\eta }_{ESS})$$

(6)

where $E_{total}$ is total energy available for use (kWh).

The battery’s state of health (SOH) will be calculated from the following:

$$Stateofhealth(SOH)={\displaystyle \frac{BatteryCapacityattime\left(C_t\right)}{NominalCapacity\left(C_{Nom}\right)}}\times 100\%$$

(7)

Average capacity will be calculated from the formulation below:

$$AverageCapacity(C_A)={\displaystyle \frac{\sum BatteryCapacityattime\left(C_t\right)}{NumberofBattery\left(N_b\right)}}$$

(8)

$$AverageStateofhealth(SOH)={\displaystyle \frac{AverageCapacityattime\left(A{C}_t\right)}{NominalCapacity\left(C_{Nom}\right)}}\times 100\%$$

(9)

$$\mathit{Required}\mathit{SLB}(R_{SLB})={\displaystyle \frac{BatterySize\left(B_S\right)}{RatedCapacity\left(R_C\right)\times NominalVoltage\left(N_V\right)\times {SOH}^{\ast }}}$$

(10)

The deployment of a 30 kW on-grid energy storage system (ESS) using used electric vehicle (EV) batteries in the Multimedia University signifies a groundbreaking effort to promote sustainable energy usage among the campus community. The project began by carrying out a thorough evaluation of the university’s energy usage patterns, periods of high demand, and the amount of space available for the installation of an energy storage system (ESS). Utilizing second-life electric vehicle (EV) batteries for the purpose of energy storage presents a financially viable and environmentally sustainable approach to addressing the power demands of the cafe, hence diminishing its dependence on traditional energy sources. Figure 4 shows in the practical implementation of an energy storage system using second-life electric vehicle batteries at Multimedia University. Figure 5 represents the system architecture and configuration of a 30 kW on-grid ESS that was installed in Multimedia University Cafe utilizing an SLEVB. Another 3.6 kWh solar-powered streetlight using second-life electric vehicle batteries installed in Gamuda Cove, in collaboration with Energreen Tech Sdn Bhd and Gamuda Land, is shown in Figure 6. Figure 7 shows the blueprint for a solar-powered streetlight using SLEVBs. The system comprises a 300 W solar panel, a controller with Maximum Power Point Tracking (MPPT) capability, a 120 W streetlight, and batteries designed to store energy for a duration of 2.5 days [54]. This battery capacity is intended to account for weather fluctuations and the possibility of limited sunlight on specific days. Thorough testing and commissioning protocols were implemented to validate the functioning, efficiency, and adherence to safety regulations of the energy storage system (ESS). System performance is optimized and the lifespan of the second-life EV batteries is extended through the use of continuous monitoring and maintenance processes. Malaysia thus demonstrates its dedication to environmental stewardship, establishes a model for sustainable practices in the corporate sector, and contributes to the achievement of sustainability objectives through this actual application.

3.2.2. Challenges

One of the primary challenges is managing the degradation of used EV batteries [54]. They may still maintain a large amount of their original capacity, but their different degrees of degradation require rigorous examination and monitoring to ensure their consistent and reliable operation. Different car batteries may perform differently due to their usage patterns and condition [60]. Energy storage system efficiency depends on balancing and regulating these changes. Used batteries must be handled safely. To prevent thermal runaway and ensure a safe working environment, robust safety standards, including testing and monitoring, must be adopted. Second-life batteries lack original warranties, which is problematic. Reusing batteries might be difficult to warranty, creating questions about their long-term reliability and performance [61]. Industry standards and regulations for energy storage systems are important. Safety and performance criteria may require modifications and new components, complicating their integration.

Electric vehicle batteries can be reused in energy storage systems for sustainability and profit [62]. While challenges exist, advancements in testing methodologies, safety protocols, and regulatory frameworks are expected to facilitate the widespread adoption of this innovative practice. Striking a balance between sustainability goals and technological considerations will be essential for realizing the full potential of second-life EV batteries in ESSs. Figure 8 shows the efficiency of the different battery technologies used in energy storage systems.

4. Readiness Assessment of Energy Storage Systems (ESSs)

Energy storage systems’ (ESSs) readiness assessments are essential for assessing their feasibility and efficacy in diverse circumstances. Their energy demands and patterns, infrastructure compatibility, regulatory environment, technology selection, financial viability, risk assessment, grid connectivity prospects, operational concerns, and environmental and social impact are all examined.

Table 6. Compatibility assessment of energy storage systems (ESSs).

Aspect	Analysis
Compatibility with Existing PV Installations	Energy storage systems (ESSs) work well with Malaysian PV installations. ESSs can improve PV system efficiency and reliability by storing excess energy during high solar irradiance periods and discharging it during periods of low solar output or high energy demand. This lets PV system owners maximize self-consumption, reduce grid dependence, and maximize their renewable energy use. ESSs can be integrated with new and existing PV installations with a proper system design and setup, minimizing compatibility difficulties.
Availability of ESS Technologies in the Market	Malaysia has a growing market for energy storage system (ESS) technology. Local and foreign manufacturers offer lithium-ion, lead-acid, flow, and sodium-ion ESS technologies. The increased interest and investment in innovative ESS solutions like second-life electric vehicle (EV) batteries and hybrid energy storage systems expands PV system owners’ energy storage options.
Grid Infrastructure Capacity for ESS Integration	Malaysia’s grid infrastructure can integrate energy storage systems (ESSs). ESSs can help the grid with voltage regulation, frequency stability, and grid congestion by offering auxiliary services, peak shaving, and grid stabilization. To achieve their seamless integration and optimal operation, significant ESSs deployment may require grid infrastructure modifications, including grid-scale energy storage systems and smart grid technology.

shows the compatibility of energy storage systems (ESSs) with existing photovoltaic (PV) installations, their market availability, and Malaysia’s grid infrastructure’s capacity to accept ESSs.

Overall, the compatibility of ESSs with existing PV installations, the availability of ESS technologies in the market, and the grid infrastructure’s capacity to accommodate ESSs in Malaysia indicate favorable conditions for the widespread adoption of energy storage solutions in the country’s renewable energy landscape [63]. However, continued investments in the development of technology, grid modernization, and regulatory frameworks are essential to fully unlock the potential of ESSs and accelerate the transition towards a sustainable energy future. Various factors influence the integration of energy storage systems with second-life electric vehicle batteries in Malaysia, and these are depicted in

Table 7. Readiness factors for integration of energy storage systems.

Readiness Factor	Description	Assessment
Technical Feasibility	Evaluation of the technical compatibility, reliability, and performance when integrating second-life EV batteries with ESSs	High
Regulatory Framework	Assessment of existing regulations and policies governing energy storage and EV battery repurposing in Malaysia	Developing
Economic Viability	Analysis of the cost-effectiveness, return on investment, and financial incentives for ESSs using second-life EV batteries	Moderate
Environmental Impact	Evaluation of the environmental benefits, including carbon footprint reduction and waste minimization	Positive
Infrastructure	Assessment of the existing infrastructure, including grid connectivity and battery recycling facilities	Adequate
Market Maturity	Analysis of the market readiness, demand, and adoption rates of ESSs with second-life EV batteries in Malaysia	Emerging
Public Awareness	Evaluation of public awareness, education, and acceptance of energy storage solutions and EV battery recycling	Growing
Research and Development	Review of ongoing research, innovation, and development efforts in ESS technology and EV battery repurposing	Ongoing
Industry Collaboration	Assessment of collaboration and partnerships among stakeholders, including the government, industry, and academics	Increasing

.

4.1. Economic Viability

Different factors must be evaluated to determine the financial viability and profitability of integrating photovoltaic (PV) systems with second-life electric vehicle batteries (SLEVBs) in Malaysian energy storage systems (ESSs).

Table 8. The economic potential of integrating PV systems with SLEVBs in Malaysian ESSs.

Aspect	Details
Initial Investment Costs	Installation of a 5 kW rooftop PV system: MYR 20,000 Purchase of a 10 kWh ESS with an SLEVB: MYR 25,000 Total Initial Investment: MYR 45,000
Operational Savings	Average monthly electricity bill savings: MYR 200 Annual electricity bill savings: MYR 2400
Revenue Streams	Net Metering: assuming a feed-in tariff rate of 0.30 MYR per kWh for exported energy, the homeowner earns additional revenue for surplus electricity exported to the grid Estimated annual revenue from net metering: MYR 600
Payback Period and Return on Investment (ROI)	$PaybackPeriod={\displaystyle \frac{InitialInvestment}{AnnualSavingsandRevenue}}$ $={\displaystyle \frac{RM\mathrm{45,000}}{(RM2400+RM600)}}=15years$ $ROI={\displaystyle \frac{(TotalSavingsandRevenueoverSystemLifetime-InitialInvestment)}{InitialInvestment}}$ $={\displaystyle \frac{\left[\right(RM3000/year\times 25years)+(RM600/year\times 25years)-RM\mathrm{45,000}]}{RM\mathrm{45,000}}}$ $=25\%$
Financial Incentives and Financing Options	The homeowner may be eligible for government incentives such as rebates or tax credits for renewable energy installations. Green financing options offering low-interest loans or favorable repayment terms may further reduce the upfront investment burden
Maintenance and Operational Costs	Estimated annual maintenance costs of PV-ESS: MYR 500 Total maintenance costs over 25 years: MYR 12,500
Project-specific Factors	Solar irradiance levels and energy consumption patterns at the residential location influence the system’s performance and potential savings. Grid connection costs and regulatory requirements may impact project feasibility and financial returns

shows the economic potential of integrating PV systems with SLEVBs in Malaysian ESSs.

Integrating PV systems with SLEVBs in residential ESSs has economic viability, with a 15-year payback and 25% ROI. The homeowner benefits from large electricity bill savings, net metering revenue, and various incentives or financing alternatives that make the project financially attractive despite the extended payback time. The economic viability of PV-ESSs’ integration into Malaysia depends on system costs, energy savings, income streams, financial incentives, and project-specific factors [64]. Economic feasibility must be appropriately assessed by conducting a detailed financial study for each project. PV-ESS integration’s value should also include non-financial benefits like energy independence, environmental sustainability, and resistance against rising electricity prices.

4.2. Environmental Impact

The environmental impact of PV-ESS integration must be assessed. This includes assessing greenhouse gas emission reductions, energy efficiency improvements, and ESS technology’s environmental impacts. Photovoltaic (PV) systems integrated with energy storage systems (ESSs) can reduce greenhouse gas (GHG) emissions in Malaysia depending on their deployment scale, energy mix, PV-ESS efficiency, and energy demand. Quantification of this may involve comprehensive study and modeling, but we can estimate based on data and assumptions. By burning fossil fuels like coal and natural gas for power generation, Malaysia’s energy sector contributes significantly to GHG emissions, according to the Ministry of Energy and Natural Resources. Electricity generation accounted for 33% of Malaysia’s GHG emissions in 2018 [65]. Malaysia can reduce tis fossil fuel energy output, especially during peak demand, by integrating PV installations with ESSs. PV systems can replace coal and natural gas in electricity generation, lowering GHG emissions.

We can estimate GHG emission reductions using a conservative estimate of 1 MW of installed PV capacity, with ESS integration replacing fossil fuel-based power for part of the day. When replacing fossil fuel-based generation, each megawatt hour (MWh) of solar electricity generated in Malaysia can avert 0.8 metric tonnes of CO₂ emissions, according to IRENA, assuming the integrated PV-ESS replaces fossil fuel-based power 50% of the time (e.g., during daylight or peak demand).

$$\begin{gathered} \text{Reduction per 1 MW of Installed PV Capacity}=1 \mathrm{M}\mathrm{W}\times 0.8 \mathrm{m}\mathrm{e}\mathrm{t}\mathrm{r}\mathrm{i}\mathrm{c} \mathrm{t}\mathrm{o}\mathrm{n}\mathrm{s} {\mathrm{C}\mathrm{O}}_2/\mathrm{M}\mathrm{W}\mathrm{h}\times 50\% \\ =0.4 \mathrm{m}\mathrm{e}\mathrm{t}\mathrm{r}\mathrm{i}\mathrm{c} \mathrm{t}\mathrm{o}\mathrm{n}\mathrm{s} {\mathrm{C}\mathrm{O}}_2\mathrm{p}\mathrm{e}\mathrm{r} \mathrm{h}\mathrm{o}\mathrm{u}\mathrm{r} \\ \text{Annual Reduction per 1 MW of Installed PV Capacity} =0.4 \mathrm{m}\mathrm{e}\mathrm{t}\mathrm{r}\mathrm{i}\mathrm{c} \mathrm{t}\mathrm{o}\mathrm{n}\mathrm{s} {\mathrm{C}\mathrm{O}}_2/\mathrm{h}\mathrm{o}\mathrm{u}\mathrm{r}\times 24 \mathrm{h}/\mathrm{d}\mathrm{a}\mathrm{y}\times 365 \mathrm{d}\mathrm{a}\mathrm{y}\mathrm{s}/\mathrm{y}\mathrm{e}\mathrm{a}\mathrm{r} \\ =3504 \mathrm{m}\mathrm{e}\mathrm{t}\mathrm{r}\mathrm{i}\mathrm{c} \mathrm{t}\mathrm{o}\mathrm{n}\mathrm{s}{\mathrm{C}\mathrm{O}}_2/\mathrm{y}\mathrm{e}\mathrm{a}\mathrm{r} \end{gathered}$$

Therefore, every 1 MW of installed PV capacity with ESS integration is estimated to reduce approximately 3504 metric tons of CO₂ emissions annually in Malaysia. This is a simplified estimate, because emissions savings may vary depending on project specifics, system efficiency, grid circumstances, and other factors. Complete lifecycle assessments and comprehensive modeling would improve GHG emission reduction estimates for PV-ESS integration in Malaysia.

As electric vehicles become more popular worldwide and in Malaysia, EVB recycling and sustainable battery management are becoming more important. The recycling business surrounding electric vehicle batteries (EVBs) in Malaysia possesses the capacity to make a significant contribution towards the mitigation of carbon emissions. Malaysian businesses, research organizations, and governments may be investigating EVB recycling and battery sustainability. These initiatives may include R&D, pilot studies, and collaborations to develop efficient and ecologically friendly recycling technologies and processes. Organizations involved in EVB recycling in Malaysia are shown in

Table 9. List of organizations involved in EVB recycling in Malaysia.

Company/Organization Name	Description/Activities
Cenviro Group	Leading environmental solutions provider offering waste management services including battery recycling and hazardous waste disposal.
Greenrecycle Sdn Bhd	Recycling company specializing in various materials including batteries and electronic waste.
Battery Recycling Malaysia	Company focused on the collection and recycling of various types of batteries, including EV batteries, to recover valuable materials and reduce environmental pollution.
Mitsubishi Electric (Malaysia)	Involved in various industries, including the automotive industry, with potential initiatives or partnerships related to EV battery recycling and sustainability.
Universiti Putra Malaysia (UPM) & Multimedia University (MMU)	Research institution working with industry partners to develop sustainable EV battery recycling solutions.
Malaysia Automotive, Robotics and IoT Institute (MARii)	Malaysian automobile industry development agency under the Ministry of International Trade and Industry (MITI) which maybe active in EV battery recycling and sustainability.
Local Scrap Metal Dealers and Recycling Centers	EV batteries can be collected and recycled by local scrap metal merchants and recycling centers in Malaysia.

.

5. Policy and Regulatory Framework

Government policies and regulations are crucial to ESS-PV integration. Malaysia’s energy regulations, tariffs, and incentives should be reconsidered to encourage ESSs’ implementation.

Table 10. Malaysia’s policy and regulatory framework for integrating ESSs with SLEBs.

Policy/Regulation	Description
National Renewable Energy Policy (NREP)	Malaysia’s NREP aims to increase the share of renewable energy in the country’s energy mix. It provides strategic directions and sets targets for renewable energy deployment, which may include provisions for integrating ESSs with second-life EV batteries [7].
Sustainable Energy Development Authority (SEDA) Act	The SEDA Act established the Sustainable Energy Development Authority (SEDA) Malaysia, responsible for promoting and regulating renewable energy in Malaysia. SEDA may implement programs and initiatives supporting the integration of ESSs with EV batteries [7].
Energy Commission Act	The Energy Commission Act empowers the Energy Commission of Malaysia (EC) to regulate the electricity supply industry in Malaysia. The EC may develop regulations and guidelines for integrating ESSs with EV batteries, ensuring their safety, reliability, and grid compatibility [66].
Grid Code	The Grid Code sets the technical and operational requirements for connecting and operating electricity systems in Malaysia. It may include provisions for integrating ESSs with EV batteries and specify grid connection standards, safety requirements, and operational protocols [67].
Net Energy Metering (NEM) Scheme	Malaysia’s NEM scheme allows renewable energy consumers to offset their electricity bills by exporting excess energy to the grid. It may support the integration of ESSs with EV batteries by providing incentives or tariff structures for energy storage and self-consumption [7].
Environmental Quality Act	The Environmental Quality Act governs environmental protection and pollution control in Malaysia. It may regulate the recycling and disposal of EV batteries and ESS components, ensuring compliance with environmental standards and minimizing adverse environmental impacts [68].
National Automotive Policy (NAP)	The NAP outlines Malaysia’s strategy for its automotive industry, including regulations and incentives for electric vehicles (EVs). It may address battery recycling and repurposing, creating opportunities for integrating second-life EV batteries into stationary storage applications [69].
Industry Standards and Certifications	Various industry standards and certifications, such as ISO standards and product certifications, ensure the quality, safety, and performance of ESS and EV batteries. Compliance with these standards is essential for regulatory approval and market acceptance [70].

shows Malaysia’s policy and regulatory framework for integrating ESSs with SLEBs.

This covers Malaysian energy storage systems’ integration with second-life electric vehicle batteries in terms of legislation, regulations, and standards. Malaysia’s energy transition and sustainability goals are supported by these laws and regulations, which offer the regulatory framework, incentives, and guidelines for integrating ESSs with second-life EV batteries.

6. Case Studies

Case studies of successful PV-ESS integration projects in Malaysia can illuminate their practical use and benefits. The following Malaysian examples use energy storage systems (ESSs) that use second-life electric vehicle (EV) batteries:

• Residential Energy Storage: A residential home development in Kuala Lumpur uses ESSs and second-life EV batteries to store excess solar energy from rooftop photovoltaic panels [4]. Each household has a 10 kWh ESS using retired EV batteries to maximize solar energy self-consumption and reduce grid dependence.
• Commercial Energy Management: A Penang shopping mall uses ESSs with second-life EV batteries to optimize energy management and lower peak demand charges [71]. The 500 kWh system stores surplus energy during off-peak hours and discharges it during peak demand, decreasing the mall’s energy expenditures and improving grid stability.
• EV Charging Infrastructure: Malaysian EV charging stations use ESSs and second-life EV batteries for quick and dependable charging [4]. A 50 kWh ESS using retired EV batteries at each charging station enables the continual charging of electric vehicles and reduces the grid load during peak hours.
• Industrial Microgrid: The Johor Bahru industrial park has created a renewable energy-powered microgrid with ESSs and second-life EV batteries. The 1 MWh microgrid optimizes energy usage, reduces grid dependency, and improves power outage resilience for the park’s manufacturing facilities [63].
• Grid Support Project: Malaysia’s national utility, Tenaga Nasional Berhad (TNB), has developed a pilot project with EV manufacturers to reuse dead EV batteries for grid support [72]. These 2 MWh ESS units, used across various substations, regulate frequency and support voltage, improving grid stability and reliability countrywide.

Malaysia has made significant strides in promoting renewable energy, particularly through the deployment of photovoltaic (PV) systems, as part of its strategy to diversify its energy mix and reduce its dependency on fossil fuels. However, the intermittent nature of solar power generation poses challenges to grid stability and reliability [73]. Energy storage systems (ESSs) present a promising solution by enabling the storage of surplus energy during peak generation for later use, thereby enhancing grid resilience and supporting the integration of renewable energy sources. PV technology in Malaysia has advanced, with increasing efficiency and capacity, making it suitable for large-scale deployment. ESS technologies, including lithium-ion batteries and potentially second-life electric vehicle batteries (SLEVBs), offer scalable solutions to manage intermittency and optimize energy use.

7. Conclusions

This research paper examined the readiness of Malaysian photovoltaic (PV) systems to integrate with energy storage systems (ESSs) utilizing second-life electric vehicle batteries (SLEVBs). Our analysis delved into the technological feasibility, policy and regulatory frameworks, economic viability, and environmental impacts of this integration. Our findings indicate that Malaysia is well positioned to leverage its abundant solar resources and emerging electric vehicle industry to enhance energy resilience, reduce carbon emissions, and optimize energy use through PV-ESSs.

This study highlights that while there are significant opportunities, several hurdles must be addressed to maximize the integration of PV systems and ESSs. These challenges include the need for improved governmental support and regulatory frameworks to foster investment, which will overcome technological issues related to system compatibility and grid integration, and research on system performance and cost-effectiveness. Collaboration among government agencies, industry stakeholders, academics, and the private sector is essential to overcoming these obstacles and accelerating the adoption of PV-ESSs.

Our research contributes to the existing literature by offering a comprehensive analysis of the integration of second-life EV batteries into PV-ESSs in the Malaysian context. This work extends our understanding of how emerging technologies can be applied to achieve a sustainable energy future, providing valuable insights into the potential for PV-ESSs to support Malaysia’s renewable energy goals. Future research directions could include exploring advanced PV panels and battery chemistries tailored to the Malaysian climate, as well as developing sophisticated energy management systems to enhance the performance, efficiency, and reliability of PV-ESSs with SLEVBs. Additionally, further investigation into grid integration methodologies and support functions will be crucial for seamlessly incorporating dispersed PV-ESSs into the national grid while maintaining its stability and reliability.

In summary, the integration of PV systems with ESSs using second-life electric vehicle batteries represents a pivotal opportunity for Malaysia to advance towards a low-carbon energy future, bolster its energy security, and stimulate economic growth. With strategic planning and collaborative efforts, Malaysia can position itself as a leader in renewable energy adoption and achieve a more sustainable and prosperous future.