Light-emitting Diode Lamps Research Articles

Energy consumption, CO2 emissions and electricity costs of lighting for commercial buildings in Southeast Asia

Building energy intensity (BEI) has been used to assess a building’s overall energy performance. However, the energy performance, CO2 footprint and electricity costs due to lighting in buildings are currently required to assist relevant authorities to develop, revise and implement energy-efficient lighting policies that are effective and acceptable for the country. This work presents an estimation approach for lighting in commercial buildings in Southeast Asia and its decarbonisation pathway for benchmarking. Application of this approach to a selected library in Brunei Darussalam showed that an energy-efficient light-emitting diode (LED) lighting system would make the building greener. We projected reductions in lighting energy consumption by 6.7 times (3.98 kWh/m2/year), its associated CO2 emissions by 8 times (0.59 kg CO2/m2/year) and electricity costs by 8.7 times (B$7.07/m2/year) by 2050 if existing lamps in the library are retrofitted with LED lamps.

Detection of early decayed oranges by structured-illumination reflectance imaging coupling with texture feature classification models.

Citrus fruits are susceptible to fungal infection after harvest. To reduce the economic loss, it is necessary to reject the infected citrus fruit before storage and transportation. However, the infected area in the early stage of decay is almost invisible on the fruit surface, so the detection of early decayed citrus is very challenging. In this study, a structured-illumination reflectance imaging (SIRI) system combined with a visible light-emitting diode (LED) lamp and a monochrome camera was developed to detect early fungal infection in oranges. Under sinusoidal modulation illumination with spatial frequencies of 0.05, 0.15, and 0.25 cycles mm–1, three-phase-shifted images with phase offsets of − 2π/3, 0, and 2π/3 were acquired for each spatial frequency. The direct component (DC) and alternating component (AC) images were then recovered by image demodulation using a three-phase-shifting approach. Compared with the DC image, the decayed area can be clearly identified in the AC image and RT image (AC/DC). The optimal spatial frequency was determined by analyzing the AC image and pixel intensity distribution. Based on the texture features extracted from DC, AC, and RT images, four kinds of classification models including partial least square discriminant analysis (PLS-DA), support vector machine (SVM), least squares-support vector machine (LS-SVM), and k-nearest neighbor (KNN) were established to detect the infected oranges, respectively. Model optimization was also performed by extracting important texture features. Compared to all models, the PLS-DA model developed based on eight texture features of RT images achieved the optimal classification accuracy of 96.4%. This study showed for the first time that the proposed SIRI system combined with appropriate texture features and classification model can realize the early detection of decayed oranges.

Vis LED Photo-Fenton Degradation of 124-Trichlorobenzene at a Neutral pH Using Ferrioxalate as Catalyst.

Chlorinated organic compounds (COCs) are among the more toxic organic compounds frequently found in soil and groundwater. Among these, toxic and low-degradable chlorobenzenes are commonly found in the environment. In this work, an innovative process using hydrogen peroxide as the oxidant, ferrioxalate as the catalyst and a visible light-emitting diode lamp (Vis LED) were applied to successfully oxidize 124-trichlorobenzene (124-TCB) in a saturated aqueous solution of 124-TCB (28 mg L−1) at a neutral pH. The influence of a hydrogen peroxide (HP) concentration (61.5–612 mg L−1), Fe3+ (Fe) dosage (3–10 mg L−1), and irradiation level (Rad) (I = 0.12 W cm−2 and I = 0.18 W cm−2) on 124-TCB conversion and dechlorination was studied. A D–Optimal experimental design combined with response surface methodology (RSM) was implemented to maximize the quality of the information obtained. The ANOVA test was used to assess the significance of the model and its coefficients. The maximum pollutant conversion at 180 min () was obtained with Fe = 7 mg L−1, HP = 305 mg L−1, and I = 0.12 W cm−2. The effect of two inorganic anions usually presents in real groundwater (bicarbonate and chloride, 600 mg L−1 each) was investigated under those optimized operating conditions. A slight reduction in the 124-TCB conversion after 180 min of reaction was noticed in the presence of bicarbonate (8.31%) and chloride (7.85%). Toxicity was studied with Microtox® (Azur Environmental, Carlsbad, CA, USA) bioassay, and a remarkable toxicity decrease was found in the treated samples, with the inhibition proportional to the remaining 124-TCB concentration. That means that nontoxic byproducts are produced in agreement with the high dechlorination degrees noticed.

Covalent organic frameworks (COFs)-derived nitrogen-doped carbon/reduced graphene oxide nanocomposite as electrodes materials for supercapacitors

This study reports the ex-situ and in-situ (one-pot) synthesis of a triazine covalent organic framework (COF)/graphene oxide (GO) nanocomposite. The materials are used to synthesize N-doped carbon (N-doped C)/reduced GO (rGO) via a simple carbonization step. The nanocomposites are used as electrode materials for supercapacitors. N-doped C/rGO synthesized via the in-situ method exhibits good electrochemical performance compared to the materials synthesized via the ex-situ procedure. N-doped C/rGO_In-situ offers a specific capacitance of 234 F·g−1 at the current density of 0.8 A·g−1. Two symmetric supercapacitor devices illuminate a white light-emitting diode (LED) lamp. A device using an N-doped C/rGO_In situ electrode shows high specific energy of 14.6 W·h·kg−1 and high specific power of 400 W·kg−1, with only a 14 % decrease in the capacitance performance after 3500 cycles. The simple synthesis procedure using the in-situ method and the high electrochemical performance of the synthesized materials may advance the exploration of an effective electrode material for supercapacitors.

Mechanism of 9,10-Dihydro-9-oxa-10-phosphaphenanthrene-10-oxide degradation in UV light-emitting diodes lamp driven sodium sulfite activation process

DOPO (9,10-Dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) is emerging organic phosphorus flame retardant, which has gained greatly attention because of its adverse health effects on aquatic organisms. In this study, UV light-emitting diodes lamp driven sodium sulfite activation (UV254/Sulfite) process was employed as an advanced reduction process to remove DOPO, and its mechanisms were revealed. The pseudo first order rate constant of DOPO (kobs-DOPO) in UV254/Sulfite process initially decreased from 6.95 × 10−5 s−1 to 5.11 × 10−5 s−1, and subsequently increased to 1.61 × 10−4 s−1 as the sulfite concentration increased from 0 to 10 mM, indicating that the negative effect of HSO3- on DOPO degradation was the dominate factor in UV254/Sulfite process at low sulfite concentration (< 2 mM), while the yields of hydrated electron (eaq-) increased as the sulfite concentration gradually reaching to a high value (10 mM), resulting in enhancing DOPO degradation significantly. In addition, the coexisted water matrix in deionized water and natural surface water weakened DOPO degradation in UV254/Sulfite process, and this inhibition strengthened as the concentrations of water matrix raised. The DOPO degradation pathway indicated that eaq- attacked phosphaphenanthrene structure of DOPO and contributed to its detoxification which was confirmed by Quantitative Structure-Activity Relationship (QSAR) assessment.

Lettuce growth promoted by artificial lighting using light-emitting diodes (LED)

Understanding how the use of light-emitting diodes (LED) in artificial lighting affects plant growth is of considerable interest to Science because the application of specific light wavelengths to crops can enhance agricultural production. Therefore, the influence of LED lamps in the photosynthetically active spectrum (blue and red light) on the growth of lettuce (Lactuca Sativa) was evaluated. A factorial design was used to test 4 combinations of LED lighting (5:1; 3:1; 1:1 and 6:3) and 2 lettuce varieties (butterhead and crisphead). The plants were grown in pots in a controlled environment with a 12h-photoperiod, for 21 days. Leaf number (LN), leaf area (LA) and leaf fresh mass (LFM) were determined along with gas exchange variables (A: net photosynthesis; Ci: CO2internal concentration; and WUEi: instantaneous water use efficiency. Growth of lettuce plants was greatest in the source of variation of LED lighting with the combination 5:1, as well as the greatest photosynthetic efficiency. The crisphead lettuce was superior to the butterhead lettuce in all analyzed variables, which suggests a better adaptation to the treatments applied.

Performance estimation of image transmission in indoor visible light communication system based on variable pulse position modulation

SummaryThe dimming control feature of light‐emitting diode (LED) makes it a viable candidate for indoor lighting applications. In this study, the performance of variable pulse position modulation (VPPM) based visible light communication (VLC) system is investigated in detail for an office room of 5 × 5 × 3‐m3 dimensions. A total of four LED lamps having Lambertian radiation patterns are mounted over the ceiling of the room. Several receiver locations are chosen over the three different trajectories to evaluate the error performance of the proposed system. The height of the receiver plane is also varied to find the optimum height where error‐free data reception is achieved. Moreover, an effort is made to optimize the dimming percentage of the transmitted signal using VPPM in terms of bit error rate (BER), where the illumination requirements over the receiver plane are also as per the International Standards of Organization (ISO). The results show that the duty cycle of 50% is optimum for efficient system performance. Furthermore, a colored image is transmitted through the proposed system and the computed results reveal that satisfactory BER performance and good quality of the image is received at receiver heights ranging from 0.85 to 1.7 m, that is, approximately 2.75 to 5.6 ft above the ground plane.

Toward green manufacturing evaluation of light-emitting diodes (LED) production – A case study in China

Manufacturing of chips and their associated products is a complex and multi-step process where evaluation on the materials and environmental efficiencies is difficult, and a typical life cycle assessment cannot fulfil the role. In this research, a multiple evaluation scheme in view of green manufacturing is developed by combining critical evaluation, mass flow analysis and environmental impact assessment, in order to define the green degree for chips and lamps production of light-emitting diodes (LED). Mass and energy flow are identified with a subsequent critical evaluation for the whole process to determine the importance of 160 kinds of substances, energies, waters, pollutants, and procedures. In 96 kinds of substances, the organics and metal contained substances have higher criticality and accounting for 33.49% and 56.54%, respectively. To understand the effects of critical pollutants, a comprehensive environmental assessment factor (CEA) is then implemented, and waste water in chip preparation section has larger CEA value. As a result, ten green manufacturing level is defined through a grading decision function, and LED filament lamp reaches a higher manufacturing level than surface-mounted device (SMD) based LED lamp. By defining three scenarios, the manufacturing level of largest environmental effect scenarios is 7, reflecting the CEA of the pollutants is the most critical parameter. With this evaluation system, the green manufacturing level of one manufacturing section or different manufacturing processes can be evaluated, which can guide the identification and classification of LED lamps and other products.

Reversible Oxygen-Rich Functional Groups Grafted 3D Honeycomb-Like Carbon Anode for Super-Long Potassium Ion Batteries

Studies have found that oxygen-rich-containing functional groups in carbon-based materials can be used as active sites for the storage performance of K+, but the basic storage mechanism is still unclear. Herein, we construct and optimize 3D honeycomb-like carbon grafted with plentiful COOH/C = O functional groups (OFGC) as anodes for potassium ion batteries. The OFGC electrode with steady structure and rich functional groups can effectively contribute to the capacity enhancement and the formation of stable solid electrolyte interphase (SEI) film, achieving a high reversible capacity of 230 mAh g−1 at 3000 mA g−1 after 10,000 cycles (almost no capacity decay) and an ultra-long cycle time over 18 months at 100 mA g−1. The study results revealed the reversible storage mechanism between K+ and COOH/C = O functional groups by forming C-O-K compounds. Meanwhile, the in situ electrochemical impedance spectroscopy proved the highly reversible and rapid de/intercalation kinetics of K+ in the OFGC electrode, and the growth process of SEI films. In particular, the full cells assembled by Prussian blue cathode exhibit a high energy density of 113 Wh kg−1 after 800 cycles (calculated by the total mass of anode and cathode), and get the light-emitting diodes lamp and ear thermometer running.

Towards smart sustainable cities using Li-Fi technology: geo-location infrastructure utilizing LED street lights.

BackgroundCities are shifting toward providing more efficient services and the Internet of Things (IoT) becoming the future of things. The shift toward using eco-friendlier LED lights in lighting cities is another genuine game-changer in the future of Light Fidelity technology (Li-Fi). Li-Fi is a visible light communication (VLC) technology that uses Light Emitting Diodes (LED) bulbs for communication. The utilisation of thousands of light sources around a city acting as wireless access points and delivering location-based content will shift cities towards being smart sustainable cities. Recently, this technology got huge attention from the research community and different research has been conducted to improve this filed. However, there is a noticeable need to develop real-world systems that utilise Li-Fi technology.MethodsThis article aims to contribute to developing a Geo-Li-Fi system that uses LED lights to provide the services for collecting contextual data and delivering location-based services (LBS) in different areas of the city. The system is described along with details of its design, implementation and development. Moreover, the overall set-up of the testbed that used to evaluate the proposed system is presented. In addition, an experiment is conducted using a real-world scenario to test the functionality of the system and report the outputs.ResultsThe effect of the system is discussed according to different aspects of sustainability which include economic, social and environmental aspects. The system was tested in indoor and outdoor environments, and it can be seen that the sunlight does not affect the ability of LEDs to deliver the content during the daytime. Regarding the transmission range of the LED lamp, it can be seen that it is affected by different factors. It depends mainly on the power of lamp, so it will be increased significantly when the power of LED is increased. Also, an increase in the beam angle will result in wider coverage area which affected by the intensity.

Improved design of LED lamp circuit to enhance distribution transformer capability based on a comparative study of various standards

Nowadays, light-emitting diode (LED) lamps replaced the conventional types because of its higher brightness and lower energy consumption. The lamps represent about 20% of the total load all over the world. The sever distortion produced by LED lamps to network voltage and current waveforms became high challenge to researchers and manufacturers to reduce its effects on the electric equipment. In this paper, the severe side effects of using commercial LED lamps on transformers are investigated, analyzed and its circuit is modified to improve the exploitation of transformer capabilities. A new converter circuit for the LED lamps has been designed to minimize harmonics and improve the voltage quality, power factor (PF) and transformer capability utilization. Also, it guarantees a proper operation even the LED input voltage decreased to 40% of its rated value. To assure the effectiveness of the proposed circuit, a prototype is created and tested considering two scenarios: commercial and proposed LED lamp circuits. Comprehensive comparisons between the effects of the two scenarios on the distribution transformers are conducted. The proposed study is applied to Mansoura University campus microgrid electric network in Egypt. The microgrid is simulated via MATLAB Simulink and applied to the two scenarios. The total harmonic distortion (THD), PF, voltage notching, harmonic loss factor, K-factor, factor-K, and the related derating capacities of the network transformers are calculated and compared using the American and European standards for the prototype and simulator. The results ensure that the proposed circuit could effectively minimize the THD and improve the PF, voltage quality, and the utilization of transformer capacities.

Utilizing single light-emitting-diode (LED) lamp and silicon solar-cells visible light positioning (VLP) based on angle-of-arrival (AOA) and long-short-term-memory-neural-network (LSTMNN)

We propose and present the first proof-of-concept demonstration of an angle-of-arrival (AOA)-based visible-light-positioning (VLP) system using long-short-term-memory neural-network (LSTMNN) model. Only a single LED lamp and silicon based solar cell Rx are needed. The LSTM cell can manipulate and analyze time-serial sequential data, reducing the influence of time-dependent fluctuation and noises during the AOA data acquisition; hence, enhancing the positioning accuracy. We compare different ML models including the linear regression (LR) and artificial neural network (ANN), as well as different AOA data sequence lengths and additional LSTM layers. The experimental result reveals that the LSTMNN model outperforms the other models under evaluation. When the sequence length of 20 and one LSTM layer are employed, the mean positioning error is 1.78 cm and the 90% of the experimental data has positioning error within ∼2.9 cm. Compared to the LR model and ANN model, the mean positioning errors are reduced by 49% and 40% respectively; and the 90% cumulative distribution function (CDF) values are reduced by 3 cm and 1.3 cm respectively by utilizing the proposed LSTMNN model.

Light color and the commercial broiler: effect on behavior, fear, and stress

Light is an important component in poultry production, and it may impact bird behavior, an important component of animal welfare. Light-emitting diode (LED) lamps are of interest for broiler production since they are inexpensive to run and provide monochromatic colors. This study aimed to understand the impact of three light colors (blue, green, or white), provided by LED lighting, on behavioral expression, stress and fear levels of broilers. A total of 14,256 male and female broilers of 2 genotypes (Ross EPMx708 and Ross YPMx708) were housed in 9 rooms in 2 blocked trials (3 room replicates per light per trial), with sexes and genotypes housed in 12 separate pens per room. Behavioral expression was recorded using an infrared camera and analyzed using a scan sampling technique. To assess fear, 3 tests were conducted: tonic immobility, novel object, and response to observer. Blood was collected to evaluate chronic stress using the heterophil:lymphocyte (H:L) ratio. Data were statistically analyzed using SAS (MIXED procedure) in a 3 × 2 × 2 factorial design, with lighting treatment nested within room. Fear tests indicated reduced fear levels in birds raised under blue light (lower latency to rise during the tonic immobility test and a lower percentage of birds moving due to the passage by of an observer). No differences were observed for the novel object test. Light color resulted in changes in stress levels, indicated by a lower H:L ratio for broilers raised under blue light compared to those raised under white light. Behavior was influenced by light color, especially at 33 to 34 d of age, where birds raised under white light were more active, and birds raised under blue light spent more time resting. Overall, results indicated that light color has minor influences on behavioral expression. Utilizing blue light during the brooding and rearing phase leads to lower stress and a reduction in fear, suggesting that blue light may improve the emotional states of fear and stress, thereby improving the welfare of poultry.

Photoinitiator Selection and Concentration in Photopolymer Formulations towards Large-Format Additive Manufacturing.

Photopolymers are an attractive option for large-format additive manufacturing (LFAM), because they can be formulated from structural thermosets and cure rapidly in ambient conditions under low-energy ultraviolet light-emitting diode (UV LED) lamps. Photopolymer cure is strongly influenced by the depth penetration of UV light, which can be limited in the 2–4 mm layer thicknesses typical of LFAM. Photoinitiator (PI) systems that exhibit photobleaching have proven useful in thick-section cure applications, because they generate a photoinitiation wavefront, but this effect is time-dependent. This study investigates the light transmission and through-thickness cure behavior in (meth)acrylate photopolymer formulations with the photobleaching initiator bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide (BAPO). Utilizing an optical model developed by Kenning et al., lower concentrations (0.1 wt% to 0.5 wt%) of BAPO were predicted to yield rapid onset of photoinitiation. In situ cure measurements under continuous UV LED irradiation of 380 mW/cm2 showed that a 0.1 wt% concentration of BAPO achieved peak polymerization rate within 2.5 s at a 3-mm depth. With only 1 s of irradiation at 1.7 W/cm2 intensity, the 0.1 wt% BAPO formulation also achieved the highest level of cure of the formulas tested. For an irradiation dose of 5.5 J/cm2 at a duration of 3.7 s, cured polymer specimens achieved a flexural strength of 108 MPa and a flexural modulus of 3.1 GPa. This study demonstrates the utility of optical modeling as a potential screening tool for new photopolymer formulations, primarily in identifying an upper limit to PI concentration for the desired cure depth. The results also show that photobleaching provides only a limited benefit for LFAM applications with short (1.0 s to 3.7 s) UV irradiation times and indicate that excess PI concentration can inhibit light transmission even under extended irradiation times up to 60 s.

Synthesis of Carbon Dots with Carbogenic π-Conjugated Domains for Full-Band UV Shielding

Our skin and materials are constantly exposed to detrimental ultraviolet light (UV) rays from the sun. It is essential to protect our health and the life of materials by intercepting this detrimental high-energy radiation with UV absorbers. Carbon dots (CDs) with low toxicity and low cost have brought a choice for UV absorbers. However, high-efficiency absorption CDs that can achieve absorption in the full ultraviolet region have rarely been reported. Herein, we synthesized a full-band carbon dot ultraviolet absorber by expanding the CD π-conjugation domain. In addition, by encapsulating CDs in a polyurethane (PU) matrix, the absorptivity of the 5 wt % CDs@PU film in the ultraviolet region was 100%, and the transmittance reached 90% in the visible region, successfully protecting the two dyes from photodegradation. The UV shielding efficiency slightly decreased under the accelerated aging experiment of 288 h. Moreover, to remove the ultraviolet light in the light-emitting diode (LED), we applied a layer of the CD film to the surface of the LED lamp, and the results indicated that the UV light was successfully blocked by the CD film without affecting the LED luminescence performance. This study offers a valid method to evolve high-efficiency, nontoxic antiaging materials and healthy lighting devices.

A comparative study on harmonic analysis and thermal performance of different types of lamps for residential building

This paper investigates the analysis and study of power quality, harmonics and thermal characteristics of halogen lamps, compact fluorescent lamps (CFLs) and light emitting diode lamps (LEDs). As nonlinear loads, CFLs and LEDs produce highly distorted currents compared to halogen lamps. The harmonic absorptions of each individual tested lamp are analyzed. Then, measurements with different groups of LEDs are conducted to investigate the effects of diversity factors. Although LEDs produce considerable amount of harmonics, it is concluded that amount of harmonics can be reduced by combining various types of LEDs. In addition, it could be observed that as the number of lamps increases, the diversity factor decreases. Finally, the thermal characteristics of lamps are compared in this paper. Results show that LEDs produce less heat compared to halogen lamps and CFLs.

Far-red-emitting LaSrRO4:Mn4+ (R = Al and Ga) phosphor: Synthesis and optical properties

LaSrRO4:Mn4+ (R = Al and Ga) are prepared by the high-temperature solid-phase method in air. Their luminescence properties, crystal structure, concentration dependent spectra, time-resolved spectra, fluorescence lifetime, and luminous mechanism are systematically researched, respectively. Mn4+ ion is the luminescence center of LaSrRO4:Mn4+ (R = Al and Ga). The excitation spectra of LaSrRO4:Mn4+ (R = Al and Ga) under monitored at 715 nm lie in the range 210 – 650 nm with two main excitation peaks at ∼360 nm and 520 nm. With the excitation at 360 and 520 nm, LaSrRO4:Mn4+ (R = Al and Ga) emit far-red light and have the emission spectra covering the region from 650 to 800 nm due to the 2Eg → 4A2g transition of Mn4+ ions. The ideal Mn4+ concentration in LaSrAlO4:Mn4+ and LaSrGaO4:Mn4+ are ∼ 0.4 mol% and 0.6 mol%, respectively. The spectral properties of samples verify the crystal field s via the Tanabe-Sugano energy level diagram of Mn4+ ion. LaSrRO4:Mn4+ (R = Al and Ga) have the emission spectra match with the absorption spectra of the plant photosensitive pigments red light and far-red light, which infers their promising application in plant growth light-emitting diode (LED) lamp

New Optimal Heat Sink Design with Concave Fins for Cooling System in Light Emitting Diode Lamp

New Optimal Heat Sink Design with Concave Fins for Cooling System in Light Emitting Diode Lamp

LED layout optimization in visible light communication system by a hybrid immune clonal bat algorithm

To enhance the flatness of received optical power distribution, a hybrid immune clonal bat algorithm (ICBA) combining the bat algorithm (BA) with an immune clonal algorithm (ICA) has been proposed to optimize the light source layout of indoor visible-light communication (VLC) systems. Taking 16 light-emitting diode (LED) lamps under a rectangular layout as an example, the variance of the received light power on the receiving plane is set as the fitness function. Specifically, the fitness value is optimized by the variables of 18 elements consisting of the LED position parameters and their half-power angles. The results show that compared with the non-optimized case, BA, and ICA, the fitness value of ICBA decrease by 97.70%, 96.77% and 98.81%, respectively. The signal-to-noise ratio (SNR) variance optimized by the ICBA is the lowest, approximately 0.1037 dB, and the variance of illuminance optimized by ICBA is 62.99% lower than that optimized by ICA. Besides, compared with the non-optimized case, the BER performance of this VLC system has also been improved significantly after ICBA optimization. This study will benefit the research and development of indoor VLC systems.

High-performance large-area blade-coated perovskite solar cells with low ohmic loss for low lighting indoor applications

Emerging hybrid organic–inorganic perovskites with superior optoelectronic property demonstrate promising prospect for photovoltaic (PV) applications, in particular for low-lighting indoor applications e.g. within internet of things (IoT) networks or low-energy wireless communication devices. In order to prepare devices with high power output under low-illumination conditions, scalable fabrication techniques are preferred for large-area perovskite solar cells. In additions, one of the key parameters to achieve high-efficiency large-area perovskite solar cells is to minimize the ohmic loss to further boost the solar cell efficiency. Herein, a one-step blade-coating method assisted by hexafluorobenzene (HFB) was developed to deposit dense, large-area smooth and high-quality perovskite films with low ohmic loss. The as-fabricated devices demonstrated power conversion efficiency (PCE) of 20.7% (area of 0.2 cm2) and 16.5% (1 cm2), respectively, under standard (AM 1.5G) illumination conditions. Besides, the large-area (1 cm2) devices demonstrated a remarkable PCE of ∼ 33.8% and ∼ 30.0% under 1000 lx and 100 lx illumination provided by white light-emitting diode (LED) lamp, respectively. We exhibited a series-connected stack of large-area (totally active area ∼ 4 cm2) perovskite photovoltaic device powering up a LED under common indoor environment as an indoor self-power indicator lamp. The analysis using a single diode model suggests that the high performance of the large-area devices under low-lighting indoor conditions is highly associated with the largely reduced ohmic losses, which particularly indicate that the perovskite films by a facile and scalable blade-coating method. The presented scalable approach paves the way to designing high-performance perovskite solar cells for a variety of emerging indoor PV applications.