Questions tagged [solar-energy]
Use for questions about non-photovoltaic solar energy applications, such as passive solar heating or concentrated solar thermal power. For PV applications, use the photovoltaics tag instead.
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Most energy efficient way to decrease pressure
I'm currently working on a solar still design to enhance solar desalination productivity. One of the ways to increase productivity was to decrease humidity and pressure. I simply want to know the best ...
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What is the effect of reducing the active and reactive power rate for an inverter?
Many solar inverters which can be controlled remotely have the option to reduce the active and reactive power rate (inductive, capacitive) below 100%. An additional option is the export limit in a ...
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Find an empirical formula that relates the output voltage of a solar panel to irradiation and temperature
I want to determine the output voltage of a solar panel based on irradiation and temperature.
I have a dataset spanning three years of irradiation and temperature in Dubai, recorded every 30 minutes.
...
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Is exceeding the maximum power an issue for solar panels and inverters?
Say I have a solar panel setup which can produce a total of 16 kW peak. With an inverter that has a maximum PV input of 6kW, would this be an issue that could lead to defects? Or is it just ...
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What are the design trade-offs between Parabolic Dish (Scheffler) and Parabolic Trough (Euro Trough) Solar Concentrators?
Two types of prevalent medium-to-large-scale concentrated solar thermal fields use:
Parabolic trough or
Parabolic dish
Since 1986, hundreds of sites around the world have built arrays of Scheffler ...
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PV solar panel is producing more than is possible according to its datasheet?
I have a client in Belgium that has 16 DM400-M10-54HBB on his roof. On Saturday the 2nd of December 2023, the PV output was 3.95 kW, according to the log of the Huawei SUN2000 4.6KTL-L1 5 kVA inverter....
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Are two solars panels more efficient than only one of twice the power output?
Is there any advantage to use two 50 W solar panels in parallels instead of one 100 W panel?
As we know, the effect of partial shadow on a solar panel can make the whole panel ineffective. We want to ...
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Pump capacity calculation
I have a borewell dug in my farm and the depth of the borewell is around 195 feet. I have applied for a Solar pump subsidy and I am about to get the equipment with following details:
4.7kW solar ...
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What is the efficiency of Solar energy run turbines? Are they better or worse than Solar PV cells?
The Solar PV cell has an efficiency of 25-40%.
Now steam turbines run by coal or some other fuel have an efficiency of approximately 60-80%
What is the efficiency of steam turbines run by Solar energy?...
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Why isn't heatpump technology used for solar collector panels and boiler tanks?
All solar collector and boiler tank systems that I can find on the market use a liquid to circulate the heat between solar collector panels (or PVT panels) and boiler tanks. Is there a reason why they ...
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Estimating the effective area and temperature coeffecient of a solar panel
I have a bunch of solar panels, each one is connected to an inverter.
For each solar panel I have two sensors, a wind and a west sensor.
From every inverter, I collect the power output.
The readings ...
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Heat handling in BIPV System
In a BIPV System, how is the heat handled? I mean the cells absorb the solar radiation and along with that the heat. So how is this heat handled? I was reading that the conventional solar system is ...
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What mathematical operation should I do in order to translate from TWyr/y to TWyr_30 in this article?
In this article
https://www.sciencedirect.com/science/article/pii/S266711312200002X
the authors show a result of prediction on energy reserves (in particular solar ones) as known in 2015 (Figure 1) ...
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What is the commercial status of the solar updraft tower aka solar chimney technology?
To extract energy from the sun there are a lot of different ways. According to my knowledge the ones that receives most of the attention are photovoltaics, concentrated solar power, and the Solar ...
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How can I transport sunlight (with UV, IR etc...) across space?
I currently have a tiny vertical farm which I am trying to make as energy efficient as possible.
A big chunk of my power consumption comes from LED lights which are powered by solar panels/batteries, ...
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Solar bimetal/dilation power generator
What attempts are there been at converting on Earth's surface, night/day temperature differences, so that the dilation of a large bimetal is converted into mechanical work ?
At small scale it would ...
user12750
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Solar power system, hybrid, 48 V & 24 V inverters in parallel
I am planning on getting an off-grid/hybrid power system for my house.
We have a shortage of inverters in South Africa currently.
Is it possible to have 2 inverters in parallel: one of them 48 V (5 ...
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Is Mostly-Passive Solar Desalination Possible in a Desert Climate?
It seems like it should be possible to have almost entirely passive (minimal moving parts or machinery) solar desalinization that would be ideal for desert countries bordering the ocean. e.g. Northern ...
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Need a solar powered mechanical motor? that moves a leaver up and down low force and little distance on day/night
I'm planning to use barrels full of water to make a drip watering system. I can make the water controls from a pretty easy toilet fill&flush valves and balance it so it needs a very light push on ...
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What materials to use indoors to absorb sunlight and store it as heat?
This is a very practical question; the underlying principles are, I imagine, extremely well-known.
I'm buying a new place in the northern hemisphere (49° N) with lots of southern (or rather SES) ...
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how much energy is stored in a car under sun ? (car interior)
When a car is under the sun, the interior is hot. This is due to the interior, especially seats, which are black (or a dark color) so that they heat under sun light and restitute this heat to the air. ...
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Can a grid connected PV system deliver power backwards through the distribution transformer?
If there is no local load demand can a residential roof top grid connected PV system deliver power across distribution transformer [up to the higher voltage grid]?
Suppose my grid connected solar pv ...
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Solar Thermal Collector to Boil Water (100 deg C)
Is it possible to build a Solar Thermal Collector that boils water to 100 deg C?
I've seen a lot of Solar Thermal Collectors that claim to be able to boil water, but every example demonstration that I'...
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A shape that focuses light from the widest range of incidence angles into a smaller area
I remember reading about devices which were roughly hyperboloid in shape that had the property of focusing light from a much wider range of incidence angles than a parabollic antenna. I think they ...
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Can air currents be used to keep dust from settling on solar panels?
I've been trying to build products to start my own solar company. A common issue with solar panels is dust accumulation, which reduces the already low efficiency even further. I've been working on ...
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Best metal for solar energy collection in an evacuated tube solar water heater
I am building an evacuated tube array for a solar water heater and I am selecting the materials to use for the tubing and the collectors (the places connected to the tubing that help absorb the solar ...
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How large would a solar panel array need to be in order to supply all the world's energy?
This story from 2016 claims that all the world's energy needs could be supplied by covering 1% of the Sahara in solar PV panels.
Was (is?) this true, and if not, how would you go about approximating ...
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Why are there no propane refrigerator air-conditioning units that run on solar heat?
I was thinking about how hot it was outside, when a thought came to me. There are propane refrigerators, so why not replace the propane as the heat source with solar heat and then change it from a ...
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Problem with relationship between shunt resistance and grain boundaries in a solar cell [closed]
Here is the correct answer from another stack website.
The higher shunt resistance means that higher the
polycrystalline lattice irregularity and many grain boundaries. This
means higher current ...
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Why do monocrystalline solar cells have rounded/cropped edges?
What is the meaning of this croped part? Why do they crop it, rather than let it be full square?
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Why do solar cells need to be square-shaped?
There were circular solar cells 30 years ago. Why do we have square-shaped solar cells now? Why square?
Furthermore,
Why do monocrystalline solar cells have rounded/cropped edges?
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Mirror specification used in Solar Fresnel Collector systems
Im designing a Linear Fresnel collector system, and wanted to know what type of mirrors would be suitable for use as the reflectors. Thickness, type, coating etc. I couldnt find a manufacturer of ''...
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Use of Cast Acrylic sheets as glazing in a Flat Plate Collector for domestic water heating
I am designing a FPC for heating water. I was wondering about the feasibility of replacing the usual Low-iron tempered glass with Cast Acrylic sheets [owing to non-availability of the former where Im ...
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Are cameras' CCDs just elaborate tiny solar cells?
While watching How It's Made episode on CCDs, this just springed to my mind... I always though of CCDs as of some kind of alien technology. Only now I realized that it's just an array of silica ...
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explaining ohmic loss and understanding inverter efficiency curve
I'm trying to understand an efficiency curve from PVsyst, using this documentation
However, I'm not sure what this sentence means:
This production is penalized by an ohmic loss$^1$ of the internal ...
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Explanation for photovoltaic circuit
My background is in Environmental Science, although I have recently been taught in the basics for energy engineering especially for solar panels.
I'm currently using PVsyst to build solar panels on a ...
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Which kind of thermal oil is used in solar thermal power plants and how are they produced?
I'm currently researching some mechanisms for a simulation game, which also covers several electrical power plant options. As part of this, I'm currently looking at a solar thermal power plant, which ...
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Correct wind Weibull distribution for wind+solar system
I'm trying to forecast the peak power output for a wind + solar system. The solar output as a function of time of day and month can be forecasted easily. I also have the historical wind speed for a ...
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Internal Tent Temperature
Here is the problem I am working on:
"Consider a perfectly sealed polygonal tent with the sun directly overhead. The solar irradiance of a surface 90° to the sun’s rays is 1,000 W/m2. However, ...
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Capacity credit vs capacity factor
What is the difference between capacity factor and capacity credit? I know that capacity factor = annual generation / (installed capacity * 8760) but I don't understand how capacity credit is ...
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For a given surface area of sunshine are the latest solar panels more or less efficient than a Stirling engine?
I was wondering if the efficiency of current solar panels are better or worse than the current state of the art Stirling engines. I understand the former isn't a static variable and solar panels are ...
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Adding a black plastic layer to increase retained heat in compost
I have some invasive climbing weeds to break down into compost. I don't want to discard the biomass, but I do want to thoroughly kill all the weeds and ideally the seeds over a period of months.
The ...
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Can we use an open expansion tank in solar water heating system?
We all know that in an indirect (closed loop) hydronic system, an expansion tank is needed ,to deal with thermal expansion of the circulating water, that can be either open expansion or closed ...
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How do you calculate heat transfer due to solar radiation for a multi-layer wall given the incident solar radiation and wall specs?
Trying to come up with a MATLAB code for calculation of heat transfer due to incident radiation on a building's walls, would the solution involve using the conduction equation only? What would be the ...
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Would using activated carbon in a solar air collector help due to increased surface area?
Basically put a light coat of activated carbon on the collector, because surface area is so great, but I cant find info on its ability to collect solar energy, esp. compared to other materials. Im ...
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Joining the negative PV wires of 3 solar arrays for 3 MPPT controllers in an inverter?
My Inverter has 3 MPPT inputs. For some design simplifications (Involving ATS), i would like the three arrays to have separate PV+ but join the PV- wires together at a bus-bar and take the Inverter ...
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How do multiple enphase microinverters stay synced to the grid?
In a prior question it was established that any string or microinverter that is grid tied must put out sinusodial power. But there is also the task of being in sync with the grid. It seems from ...
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Solar power, Battery power to mains voltage
My question is what is the most efficient way to convert 48V D.C. to 220V A.C. Not the easiest or most cost efficient but the most efficient electrically?
Also if anyone has any cheats on the best ...
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Is it economical to use solar energy to manufacture solar panels?
Estimates of area needed to be covered by solar panels to power all of the US using only solar are about equal to a 100 mile by 100 mile tract of land. But solar panels have a lifespan of only a few ...
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What's the name of this parameter?
$ P_m=P_n*{G\frac1{G_{STC}}}*[1-\gamma*(T_c-25)]$
This equation is applied on sollar cells. $ P_m$ is the mean power produced in 15 minutes, $P_n$ is the nominal power [W], G is the insolation [W/m2]...
user20096