Design of portable emergency lamp utilizing thin film solar cell and inflatable case

Lighting is an essential thing in performing daily activities and without sufficient lighting we will be difficult to see clearly. The problem is when there is no electricity, for example when we go to a cave or a forest or when there is a natural disaster that shuts down all the electricity. A portable lamp that can be charged by exposing the lamp to sun light can be one of the solution to overcome this problem. Energy Harvesting is a concept where an energy is captured, stored, and used with several technologies including solar technology. Energy Harvesting technology is used in many applications such as calculator, electrical cars or day-to-day lighting This paper will discuss about an application of solar panel in portable LED lamp, that can be used in the night and can be charged during daytime with solar panel. The solar panel, LED, and the battery is integrated in one circuit so there will be more space convenient for user. Solar emergency lamp can be used to illuminate the pathway in mountain or caves and the lamp can float in the water because it case is inflatable. Rechargeable Li-ion Battery 3.7 V 500 mAh and 10 LED SMD is used in this lamp. The proposed design is using a transparent PVC for the case of the lamp. The lamp can be turned on approximately for 4 hours from fully charged battery with 10 LED lamp. The illumination of solar portable emergency lamp was measured using lux meter. The illumination average of the solar portable emergency lamp is 17.58 lux with a deviation of 7.3 lux with medium bright mode. The illumination average of the solar portable emergency lamp is 32.85 lux with a deviation of 12.4 lux for the full bright mode. The Illumination is measured in 50 cm below the solar portable emergency lamp with 9 measured point consisting of 3 rows and 3 columns.

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CP Antenna with 2 × 4 Hybrid Coupler for Wireless Sensing and Hybrid RF Solar Energy Harvesting

Sensors ◽

10.3390/s21227721 ◽

2021 ◽

Vol 21 (22) ◽

pp. 7721

Author(s):

Irfan Mujahidin ◽

Akio Kitagawa

Keyword(s):

Thin Film ◽

Solar Cell ◽

Energy Harvesting ◽

Circular Polarization ◽

Thin Film Solar Cell ◽

Wireless Sensor ◽

Polarization Sensitivity ◽

Solar Energy Harvesting ◽

Hybrid Coupler ◽

Asymmetric Hybrid

The main challenge faced by RF energy harvesting systems is to supply relatively small electrical power to wireless sensor devices using microwaves. The solution is to implement a new device in a circularly polarized rectenna with circular polarization sensitivity integrated with a thin-film solar cell. Its dual-feed antennas are connected to a 2 × 4 asymmetric hybrid coupler and a multi-stage voltage doubler rectifier circuit. This configuration has a 2 × 4 asymmetric hybrid coupler used to produce 4 outputs with a 90-degree waveform phase difference. The two ports can independently be connected to the wireless sensor circuit: radiofrequency harvesting of hybrid energy solar and information equipment can be carried out with these two antennas. The Dual-Feed circular patch antenna has a two-port bandwidth of 137 MHz below −15 dB and an axial ratio of less than 3 dB, with a center frequency of 2.4 GHz with directional radiation and a high gain of 8.23 dB. It can be sensitive to arbitrary polarization of the input voltage multiplier waveform to overcome uncertainty in empirical communication environments. A parallel structure is arranged with a thin film solar cell integration from the transmitter with an output voltage of 1.3297 V with a compact composition and RF energy. The importance of adopting a wireless sensor strategy with circular polarization sensitivity and integrated RF solar energy harvesting rather than a single source method makes this research a significant novelty by optimizing the analysis of multiple wireless sensor signal access.

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