Questions tagged [energy-harvesting]

Energy harvesting devices generate power from an external source. While they may include solar, kinetic and other energy sources that are also used on a large scale the term is normally reserved for small low-power applications. An example is a wristwatch that uses kinetic energy while the wearer is walking to power the watch.

Filter by
Sorted by
Tagged with
1
vote
0answers
34 views

Ultra-low power energy harvesting wireless sensor network: technology and options

Background & Context I'm developing a project proposal for my honors thesis (officially commences at the end of July, running for one year) with the aim of designing a wireless sensor network with ...
0
votes
0answers
14 views

Supply interchanges between AA batteries in series and solar panel

I want to supply my product that has a sleep consumption of 40uA and an elevated consumption of 200mA during standard use. I want to use the solar panel to supply the 40uA during the sleeping time and ...
0
votes
1answer
86 views

How does a relay or switch work with batteries or capacitors?

I am charging my capacitor so it can act as a battery for a short period of time. I already did the calculations for the battery discharging and charging. My problem is now that I have a load, I want ...
0
votes
1answer
43 views

Energy Harvesting application capacitor selection

I have an energy harvesting application and I want to use a capacitor to store energy. Due to the application being very low power, a capacitor of around 50uF might be enough. What is really important ...
0
votes
0answers
51 views

Very low voltage BJT behaivor

I'm interested in very low supply voltage boosting. 20-200mV, the lower the better. Usually such applications use zero threshold MOSFETs, but I'm curious if BJT will do the work too. In the datasheet,...
0
votes
2answers
54 views

Capacitor's energy required for a predetermined drop in its voltage - with LDO and constant current elements as load

I am trying to understand how much energy a circuit (composed by some passives here called analog, and an MCU) will require. The system is powered through a capacitor, and the "passives" are actually ...
0
votes
0answers
51 views

Unpredicted behavior in an energy harvester circuit using max666

I conducted the simulation of a circuit used for energy harvesting. Its functioning is explained in detail in How the voltage stable mechanism work in Bridge rectifier?. But it was observed in the ...
0
votes
0answers
21 views

Simulation issue when using LT3012B

For an energy havesting application I needed a power management circuit so that it can power a wireless sensor module. The sensor module requires roughly 25mA current in active mode and 100uA in sleep ...
0
votes
0answers
24 views

Alternative ways to wirelessly power a small load

I'm working on a project which needs to power a small DC motor (50-70mA @ 3.3V). It will be placed in a picture frame hanging on the wall, therefore powering (or charging) it with a cable wouldn't be ...
1
vote
3answers
127 views

What should I do to control the impedance in piezoelectric energy harvester

I am trying to design an piezoelectric energy harvester circuit and using voltage multiplier rectifier to build it now. I am using a piezo film, LDT4-028k as a source and it has 11nF cap inside the ...
0
votes
1answer
46 views

Low voltage MPPT boost converter IC, constant input voltage

Following scenario: I have a bunch of Sunpower C50 unprocessed single solar cells. I'm trying to make a panel out of them for hiking. According to the datasheet each cell has 0.574 Vmpp an 5.65 Impp ...
0
votes
1answer
72 views

Schottky diodes in series to reduce maximum voltage at supercapacitor solar charging circuit

I use the following circuit to store solar energy harvested by photodiodes into a supercapacitor. The cap is rated at maximum 2.8V. The zener diode is rated at 3V, but depending on the harvested solar ...
0
votes
1answer
59 views

Micropower voltage regulator with discrete components

Overview I have an unregulated power source (photodiodes BPW34) from which I want to get a regulated voltage output 1V. My load consumes less than 10 microamps of current at 1 V. Constraints: I'm ...
0
votes
0answers
63 views

Overvoltage protection Piezo Harvester

I have a piezo harvester, capable of creating spikes of 50+Volts. My harvesting circuit which will be connected to the harvester output, has a maximum rating of 20Volts. Therefore I need some kind of ...
0
votes
1answer
40 views

BQ25570 Ground Layout

I am using the BQ25570 power management IC for energy harvesting from a solar panel. I am currently designing the PCB layout for the IC, and I am a bit confused about the ground. As you can see in ...
1
vote
2answers
167 views

Can an LED run by harvesting energy from mains hum? [closed]

One morning 2 weeks ago I found a green LED in a carpark attached to a deflated ballon. It had obviously landed overnight. I left it there and when I returned in the evening it was still glowing quite ...
0
votes
1answer
80 views

Can I charge a lipo battery using piezoeletric energy harvesting?

I use a 9V 800mAh lipo Okcell battery to power my ESP8266 ESP-01 with a voltage regulator to change it to 3.3V. I use the ESP to detect the voltage peak from a piezoelectric when someone is running to ...
0
votes
0answers
39 views

Piezoelectric Energy Harvesting & rectifying

I am interested in doing piezo energy harvesting. I have bought two of these piezoelectric Harvesters. One device I found, the ΒQ25570 seems to implement mppt (maximum Power point tracking), and be ...
1
vote
1answer
68 views

Which type of RF harvested device is used now?

I want to do some research about energy harvesting optimization, and I want to ask which type of RF energy harvested device is used now? first,one transmitter will transmit one signal to the energy ...
0
votes
0answers
36 views

How to create the UVLO hysteresis in energy harvesting design?

I had try LTC3588-1, BQ25570 in my project. Both of them have a UVLO function. For LCT3588-1, if choosing 1.8V output, the output will be opened once the voltage of the storage capacitor reach 4V. The ...
0
votes
1answer
52 views

Simulation of the Micro-kinetic generator

I am simulating the block diagram of the Autoquartz system during unwinding in Simulink. I want to get the current of microgenerator (Ibus), but I get an oscillating pattern, which you can see here ....
2
votes
2answers
395 views

Simple RF energy-harvesting circuit

I wanted to dabble a bit in RF energy harvesting. Nothing fancy, just see what's possible. I came up with the following circuit, but I'm a complete layman when it comes to antennas and the like. ...
1
vote
0answers
40 views

Piezo Energy Harvesting: Power Balance

I am doing some piezo and energy harvesting tests, but I am having a hard time calculating the available energy balance. I setup a voltage and current measurement for both the energy harvesting input ...
1
vote
2answers
58 views

Magnetic induction with varying rpm: Dealing with excess energy

I would like to get some advice regarding the following scenario: I want to build a cheap, small generator for an energy harvesting application. There are magnets on a rotating shaft and off-the-shelf ...
0
votes
1answer
64 views

Turn on power when voltage higher than set value

We are trying do design a circuit which works by harvesting energy from a split core current transformer. Most of the electronic works correctly, we use a 1.5F 5.5V SuperCap to provide enough power ...
2
votes
1answer
69 views

Probing with oscilloscope causes current drop

We are testing a fabricated chip with expected output current of around 4mA which is then used to charge a button cell. The input is from a PV cell. However, when we attach an oscilloscope probe onto ...
3
votes
5answers
2k views

Diode type with lowest drop voltage [duplicate]

I make a small solar energy harvester. I'm searching for the type of diode with lowest drop voltage. Any suggestion for the type of diode for me ? Thank you
0
votes
0answers
54 views

Solar power pump - Design critique and help

Okay so, I have a design that 'works' on the breadboard. But I feel like it could use some improvement. Here is my current design: simulate this circuit – Schematic created using CircuitLab ...
0
votes
0answers
35 views

Is there a Energy Harvesting Power Management and Battery Charging EVM dev kit (e.g. BQ25504) with easily adjustable voltage thresholds?

I have a BQ25504EVM-674 Energy Harvesting Power Management with Battery Charging (EHM) development board by Texas Instruments. It fulfills my requirement of charging an energy store (e.g. supercap/...
4
votes
0answers
144 views

Is it possible to power a MCU with a button press / touch? [closed]

I hope to use a piezoelectric button to harvest and produce a sufficient energy burst to power ON and bootup a MSP430 for a few ms enough to update a simple data structure (e.g. two integers stored in ...
5
votes
2answers
709 views

How to calculate the impedance of a rectifier?

I am working on RF energy harvesting. Now I am trying to calculate the impedance of the rectifier, in order to do the impedance matching. An antenna (50 ohm) receives RF signal (915 MHz) and finally ...
0
votes
2answers
243 views

“RF energy harvesting” Can rf transmitter be a rf signal generator?

I'm trying to build an rf energy harvester. But having some problem. The harvester should collect the 915MHz signal. Can I use 915MHz RF transceiver + 915MHz amplifier as the rf signal source? How ...
4
votes
3answers
249 views

UVLO for Energy Harvester circuit

A good background on the problem can be found in the document: (Under Voltage Lock-Out Design Rules for Proper Start-Up of Energy Autonomous Systems Powered by Supercapacitors). The above document ...
0
votes
0answers
32 views

Data communication in power harvesting project

I want to design a wearable gadget for elderly to detect falling. This gadget should work by energy harvesting. Now I want to find the best effitient way of power consumtion to send data to a station ...
0
votes
1answer
59 views

Harvest energy from ultra low current and high voltage source?

I have a sensor which can produce voltage upto 10 V but can only produce 50 nA of current. I tried to harvest energy using TI's BQ25570 evaluation board but the current is too low to kickstart the ...
1
vote
0answers
55 views

Help required to design a suitable energy harvester for TENG

So I am in the process of desgining a scalable Triboelectric Nanogenerator(TENG) through which I can easily harvest and store electricity in a battery or a capacitor. A TENG can be modelled as voltage ...
0
votes
1answer
31 views

How to do high switched current from small solar

I am working on a small, solar-powered application that makes use of RF and a few higher-power sensors. Those will only be on for a fraction of the time, but might consume 1A-2A at 3.3V. The ...
1
vote
1answer
49 views

Outdoor versus indoor amourphous silicon solar cells

I've read in a few articles that amorphous silicon (a-Si) based solar cells have a greater spectral response for indoor light conditions here. If this is the case, then why manufacturers emphasize ...
1
vote
1answer
136 views

Moving a magnet through coils wound in the opposite direction

Suppose I want to harvest kinetic energy by moving a magnet back and forth through a coil assembly. Faraday flashlights work by this principle, but to my knowledge those usually only have one coil. ...
1
vote
1answer
201 views

unknown op-amp current leak

I've created a dual source energy harvesting board to store energy from small energy sources, like a 3V 15mA solar panel, into a 3F 2.7V supercap and to power a small wireless node (3.3V, 30mA), but I ...
1
vote
2answers
74 views

Maximum Power Point Tracking for multiple sources

I know there are several commercial products for maximum power point tracking for a single power source (solar cells for example). But does anyone know any solution for the case where there are ...
0
votes
0answers
111 views

Voltage regulator outputs some voltage even if in shutdown

I've created a dual source energy harvesting board to store energy from small energy sources, like a 3V 15mA solar panel, into a 3F 2.7V supercap and to power a small wireless node (3.3V, 30mA), but I ...
3
votes
2answers
986 views

Current Transformers and Energy Harvesting

Current Transformers (CT)s work like any other transformer: through Faraday's law of induction, the changing magnetic flux (from the AC current flowing through the conductor) induces a proportional ...
1
vote
1answer
495 views

Is it possible to cut flexible solar PV panels down to size to suit small IoT type devices? [closed]

I've been looking for a supplier for tiny (approx 10mm x 30mm x 1mm) PV cells that you find on solar powered calculators without any success. Is it possible to cut a larger flex amorphous Si panel ...
0
votes
1answer
607 views

Brushed DC motor as generator, characterising the motor

I've read through the several topics here concerning using a DC motor as a generator but I've failed to answer my question so, apologies, I'm going to ask again. I need to use a small DC motor as a ...
-2
votes
1answer
246 views

Nanovolts to millivolts signal amplification [closed]

I need to amplify a weak signal(few nanovlts) from solenoid to few hundred millivolts. I am working on an energy harvesting device but I am unsure of the output since the DAQ(HP 34970 A) works in ...
2
votes
0answers
422 views

Solar charging a lipo battery with ESP8266 as a battery load

I am trying to add solar harvesting capability to my IoT device based on esp8266. I am using linear charge controller (MCP 73831) with solar input to charge a 500maH lipo battery. An observation when ...
1
vote
2answers
423 views

RF Voltage Multiplier

My project partner and I are working on making a rf-dc energy harvesting circuit capable of lighting an LED (even intermittently) or trickle charging a coin cell battery over a long time. We are ...
1
vote
2answers
1k views

Flash an LED with an extremely low power source

Let's say I have a very low power solar cell, which is producing a couple of uA of current at 100-200 mV for an output power of a few hundred nW. What I would like to know is what is the best (most ...
0
votes
1answer
1k views

What is the typical power that is transmitted through NFC from a smartphone

I think the question is clear. I only need a reference value, like is it in the range of 1mW or 10mW or 100mW. Clearly this will vary among smartphones. Also do you think it is possible to set the ...