Questions tagged [solar-energy]
Form of renewable energy emitted by the Sun, coming in two flavours: photovoltaic and thermal. The former, especially, relates closely to electrical engineering since it is traditionally harnessed through semiconductor devices and converted to AC in order to feed the electric grid or individual users' homes.
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How does AC backfeeding work?
How/when does AC backfeeding work (such as in a grid-tied solar power generator plugged into a 120V wall socket)? Is a slightly higher voltage required to backfeed?
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What breakers or switches are really needed on this solar setup?
I asked a question whether with DC breakers does polarity really matter?, that caught fire in the direction of whether at all to use those breakers or any breakers for that matter. The suspicion is ...
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Bidirectional Solar inverter circuit confusion
I has seen a solar inverter design and have some confusion regarding the inverter circuit I have drawn myself from an inverter. The circuit is shown below. As far as I understood going from left to ...
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How to secure ESP32-to-inverter RS232 communication by filtering commands using ATtiny?
we are working on a project where an ESP32 communicates with a solar inverter (Axpert KS/MKS/V) over RS232 to fetch status data (e.g., PV power, battery voltage) via the ...
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kWh/kWp Solar atlas meaning [closed]
I have a doubt, if I read the value of 'Specific photovoltaic power output' from pages like this solar atlas what does this relationship means? if I have 1 kWp installed capacity I will generate 3.958 ...
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Dual Buck inverter confusion
I am having a slight confusion in the dual buck converter as given in the paper. This is a model for a PV inverter. This initially has a voltage DC-DC converter that maintains the bus voltage.
What ...
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Is it possible to supply a hybrid inverter AC input from its own AC output? [closed]
As in the diagram below, will it be possible to give the inverter an AC supply coming from its own AC output?
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Solar Inverter vs DC
With, let's say a single phase, inverter with pulse width modulation which is essentially switching on and off the DC source at high frequency, then if the DC source is a battery when the switching is ...
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Solar panel 400W / 36v to battery 12V
I have received a good offer for a 400V to 36v solar panel (40V ~ 10.1Amps open circuit).
My question is, I already have a 12V solar chargers and a 12V battery.
I want to pair this with a 12V battery, ...
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Can solar panels in a power plant be switched off safely?
Can a solar panel power plant, e.g. 1 MWp, just disconnect from the power grid and "switch off" the solar panels, or is there some kind of issue with that?
As far as I know, solar panels don'...
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Managing Solar Power, battery, and load for raspbery pi - designing power management system
So, I am working on a scientific instrument that measures air quality. It uses a raspberry pi with a couple of sensors. Essentially, this instrument is going to be deployed in an Urban area in a ...
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Off Grid Without Battery Inverter [closed]
Respected Members,
In My Country Pakistan hundreds of peoples selling off grid inverters that are working without battery. But I am not sure whether it is safe or not? because solar production is not ...
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Do we need MPPT in grid synchronization and string inverters? [closed]
I have two questions regarding the MPPT grid synchronization. I have seen that it takes a few minutes for the inverter to get synchronized with the grid. I want to ask that does the inverter first ...
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Charging a battery using solar panels, and IV curve of the solar panel
I am aware that a solar panel has a fixed IV curve, and the load resistance can move the operating point of the solar panel along the IV curve.
If a solar panel was used to directly charge a battery ...
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Solar emergency LED Night light control design: Solar panel, 5 V : 3.7 V 18650 Li-ion or similar as Vref. No negative voltage. Only GND. Which Op-Amp?
Solar charging daytime with 0 V battery output to micro LED chain.
At nightfall, solar voltage drops to 0, activating Vout: 3.7 V or alternative Lithium chemistry to power 30 ft (100×) white LED rope ...
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Difference between MPPT charger and MPPT boost converter
I am quite confused regarding the MPPT charger and the MPPT boost converter. I have a hybrid inverter where I have a boost converter circuit at the beginning with inputs from the PV. The output of it ...
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Earth protection in PV + battery system
I'm building a system that looks like this:
PV -> solar charger (48 V) -> batteries (48 V) -> isolated DC/DC (48 V->12 V) -> non isolated DC/DC (12 V->3 V) -> load
The PV's are on ...
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Solar Array Control With Photocell
We did search on this topic before making this post, but this is as close as we found; Link to question from 2020: Solar Panel-Photocell Wiring
... which didn't seem to be closely enough related to ...
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Are 96V lead acid batteries a thing?
In the context of renewable energy grids (eg large-scale PV), I've seen people use 12V, 24V, and 48V batteries. I haven't seen 96V batteries.
I'm wondering, as things continue to scale-up to large-...
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Charge EV from array of small solar panels DC/AC
Suppose I have 20 solar panels specified to yield 18V, 40-80W.
What would be the best (most efficient, non-damaging) way to use this to charge an EV, if possible?
Note that it doesn't matter for me ...
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Confusion regarding solar power?
I was reading book of gilbert and i came across the following statement
One of the most useful ways to describe energy production from a PV array
is in terms of kWh/yr delivered per kW of STC rated ...
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Low Solar Panel Voltage Vmp Operation
so I'm currently working on an MPPT project using Asynchronous Buck Converter with the design :
Capacitor Input : 470uF/100V
Capacitor Output : 1000uF/100V
Inductor : 65uH
fsw : 39khz
current : 30A
...
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Why not always size solar cells and charge/power management module to three times continuous load power?
I am asking this question because it seems to me that this is necessary always, but I don't see people doing it. I see 196A battery to inverter setups with a 40A charger only. To me that seems wrong.
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Why not always connect cells in series to increase voltage in solar component setups? [closed]
I am designing a solar system which I can take to an Indio village deep into the Amazon forest, and thinking about some principles. I am talking about a 2, 3, or even 6 kW system. I see a big problem ...
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Solar panel charging Li-ion battery with PWM + MOSFET
My idea is to set up a circuit that uses a 18 V, 15 W solar panel to charge three 3.7 V 21700 Li-ion batteries in series (nominal voltage = 11.1 V) while the solar panel is connected directly to the ...
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Number of solar panels to power a level-2 EV charger
I am working on a project for my intro to engineering class. We are theoretically designing a EV charging station powered by solar panels. I found an example level-2 charger that says it is 9.2 kW at ...
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PC fan, powering directly by small 12V solar panel - adding more panels to help working with less sun
So I have a 12 V solar panel and a fan (size of a PC fan, assume 12 V and 0.15 A) that if connected directly work great in a full sun. Its located in a shady environment and if I kick-start it with my ...
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Troubleshooting Sako Solar Inverter and Osaka Battery Charging Issue
I have a solar power system comprising a Sako inverter (3.5-5.5 kW) and two Osaka P-180 S batteries with 21 plates per cell. Despite receiving input from the solar panels, the inverter does not ...
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Where does the electricity in electromagnets come from if permanent magnets from generators decrease their magnetic strength?
The question has been puzzling me for some time, I presume electrical power starts from generators, the heat produced by them(generators) cause their magnets to weaken and electromagnets have to be ...
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Symbol of short circuit (or termination) with an Earth
Can someone explain to me why the symbol of the valve arrester has a short circuit, if it is already earth? I don't understand why it is depicted like this.
Why does the valve arrester have the symbol ...
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Can I use a group switch to bypass a PV inverter?
I have an PV inverter which takes power input from
the main grid and
the PV modules/battery
Depending on availability, the power output to my house will be a mix of these inputs. In a usecase I want ...
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Disadvantages of using triac to control inverter load
I'm trying to optimise the usage of a residential solar system. It's a fairly low capacity system connected to the grid with an inverter (no batteries). There is also resistive heater which uses, on ...
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Grid tie inverter 200 W with low voltage auto disconnect
I have a grid tie inver that produces at most any day 200 watts from my 12 V battery bank. I also have a adjustable auto low voltage disconnect circuit that disconnect the 12 V from inverter when ...
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Excess PV damage load?
Assume a 200 A service with a 40 A PV and a sub panel with a 20 A breaker. If it is mid-day and if there is excess PV (say 35 A) in the main service panel and light loading the load subpanel, why does ...
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Repurpose APC UPS with Solar Panel as DC-AC Inverter, what changes needed
Firstly I have these items lying around,
330W 24V Solar Panel, APC Back-UPS Pro 1000VA/600W with dead battery
Wanted to see if I can repurpose this UPS circuitry to utilize solar panel during day time ...
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Selecting a charge time for a NiMH charger at 1C
I'm building a solar charger for an Energizer 8.4 V, 175 mAh NiMH battery with a MAX713. The solar panel is 15.4 V, 200 mA. If I charge them at 1C (175 mA), would it be better to set the charge time ...
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Confusion regarding solar cells
I am very confused by these two videos.
This video mentions at 1 minute onwards that a solar cell has a PN junction.
This video mentions N type solar panels and P type solar panels.
From that what I ...
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Combining/ Balancing multiple small solar panels
I am designing an energy harvesting system that runs off of a couple of solar cells. Each cell is a Dye-sensitised solar cell and gives out around 0.5v. Because of the placement of the cells around ...
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Limiting current/power dynamically
I recently installed solar panels and now I was looking at using the energy as efficient as possible.
All the energy produced I don't use goes to the grid, I get a small amount of money for that.
I ...
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Solar system: 40 A DC AND fuses. What is the difference between Audio and Solar version of this fuse?
So, I've purchased some 40A ANL fuses and holders for my solar controllers and I'm hooking them up tonight after the sun goes down. Due to a comment from a neighbor, I went back and reviewed my ...
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Where to place an LED to indicate the charging of a battery via a solar panel?
See the attached circuit diagram and PCB design. All I'd like to do is have a very small LED turn on when the panel is charging the battery.
Circuit description: Q1, a PNP transistor ensures that when ...
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Solar Powered Bilge Pump for Pool Heater
I am planning to build a swimming pool heater, using a solar panel to drive a bilge pump which circulates pool water through 1/2" x (2 x 60) m poly irrigation tube to heat swimming pool.
Solar ...
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How to calculate or estimate power inverter's peak power
What should be fine to consider as peak power output of an inverter when a motor starts for example?
given that:
Capacity (Rated Power): 935VA / 12 V
Solar UPS Overload:110%
Solar UPS Short Circuit ...
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Connecting a Pb battery back with a LiPo pack to combine maximum output power
I am working on my mountain cabin and am wiring it with some new electricity. In the long run, I want to switch to only LiPo based batteries but for now I still want to keep my old Pb batteries as a ...
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Is this possible? 1phase splitphase auto transformer connected to A 3phase grid
Dear reader,
I have a question about a single-phase auto transformer which is connected to a three-phase electricity grid. The windings of the auto transformer are on a common iron package.
The ...
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How to prevent a nichrome wire from melting under variable energy?
I’m experimenting with a DIY “sand battery”.
The “battery” is a pot lined inside with an insulator and filled with sand. The sand is heated by a nichrome wire placed at the bottom. The wire is ...
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Effects of Solar Distributed Generators on Utility Grid
The figure Below is a test block diagram that I would like to model and simulate in DigSILENT PowerFactory Software to analyze the effects of SDGs on the utility grid’s Power losses, Voltage ...
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Why is there loss of power between solar inverter and utility meter?
I have an on-grid 10 kW system installed with two-way recording meter. Recently I have noticed that units generated as shown by inverter are more than the units recorded by utility meter. Previously, ...
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I am trying to DIY outdoor gazebo solar lights
Im no electrical engineer. Just a bored ADHD mum trying to make her home nice and eco friendly.
So we just set up a gazebo tent un our courtyard and it gets really dark at night. We dont have any ...
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Connecting two solar panels in parallel with different voltage - circuit model
I am interested in understanding how two solar panels with different voltages in parallel work. Despite it is not recommended, but it may occur when for example one panel is defected, under shading or ...
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