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17 votes
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Why isn't heatpump technology used for solar collector panels and boiler tanks?

Heat pumps work well to extract heat from one zone and discharge it into a zone at a higher temperature. The output of solar water-heating panels is generally much higher than the boiler tank ...
Transistor's user avatar
  • 10.9k
11 votes

Can solar panels absorb heat for energy?

Yes, there are indeed combined PV-T (photovoltaic-thermal) hybrid panels that turn some of the incident light into electricity, and have a circulating fluid and heat exchanger to put some of the heat ...
410 gone's user avatar
  • 3,771
5 votes

Why isn't heatpump technology used for solar collector panels and boiler tanks?

The transmission of heat by phase change (liquid to gas and gas to liquid) IS used in some solar collectors. These are the evacuated tube type and are the "Rolls Royce" equivalent when ...
Solar Mike's user avatar
  • 15.9k
4 votes

How large would a solar panel array need to be in order to supply all the world's energy?

The U.S. National Renewable Energy Lab did a study of solar installations in the U.S. in 2013 and determined that for large-scale solar PV systems, 7.9 acres (31,970 $m^2$) of land are required on ...
LShaver's user avatar
  • 449
4 votes

Why isn't heatpump technology used for solar collector panels and boiler tanks?

You can't tie these two systems together because the demands on them are pretty much independent of one another. They each need to operate according to their own run schedule. The HVAC system runs ...
Phil Sweet's user avatar
  • 4,820
3 votes

Electrical flowchart in Microsoft Visio : issues

I had to draw electrical and hydraulic schematics in Microsoft Visio at a past job. I'm glad that is behind me because that software is barely good enough for making flow charts. I would never ...
ericnutsch's user avatar
  • 8,201
2 votes

How can I add roof-mounted solar panels to a van without making it unstable at highway speeds?

I work for a company that, builds custom truck bodies and upfits vans, though we do not work with GM/Chevy vehicles. Your best source of information will be in the Body Builder Guide that GM provides ...
DLS3141's user avatar
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2 votes
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What's the name of this parameter?

It's the temperature coefficient of the panel. It varies by panel, but 0.005 (0.5%) is a fairly normal value for it. Its unit is 1/degree C. It's the rate at which cell efficiency drops off, as the ...
410 gone's user avatar
  • 3,771
2 votes

Is it possible to cook with low power PV systems (under 300 W)

Have you considered a solar oven? The kind that sits in the sun and is heated by the sun's rays with no electricity or other power source. For cooking it'd be more efficient than a PV system. ...
Matt24's user avatar
  • 21
2 votes

Does this PID-like algorithm make any sense for a solar inverter?

The algorithm The standard control system is depicted below and has the following signals reference signal: $r(t)$ error signal: $e(t) = r(t) - y_m(t)$ input/control signal: $u(t) = K_p e(t) + K_i \...
useless-machine's user avatar
2 votes
Accepted

Explanation for photovoltaic circuit

Diode Like you assumed Panels: These are the PV panenls that produce current. They produce DC current I and DC voltage V Inverter: the inverter converts the DC current and Voltage from the panels to ...
NMech's user avatar
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1 vote

Why isn't heatpump technology used for solar collector panels and boiler tanks?

I'm not quite sure what you meant by your question - about boilers using gas vs water. Are we talking about refrigerants being liquid or gas at a particular point in the cycle? circulating hot water ...
M Szil's user avatar
  • 21
1 vote

How do I properly store lead-acid batteries?

Remember that in a car, a lead-acid battery is subjected to routine temperature excursions from -20F to +140F under the hood, and this does not ruin the battery. The critical issue with long-term ...
niels nielsen's user avatar
1 vote

36V solar panel with a 12V battery, results in 12 watts a day?

It will charge at 5 amps until the battery reaches float voltage, then the charge controller will turn off. After it turns off, it won't charge any more. If it stays on all day, charging at 5A for 10 ...
david's user avatar
  • 819
1 vote

36V solar panel with a 12V battery, results in 12 watts a day?

I may be wrong but from memory back in the day solar controllers had quite tight max panel voltage limitations, these days now that MPPT for 12/24v are ubiquitous not so much. For instance this is ...
Greg Locock's user avatar
1 vote

36V solar panel with a 12V battery, results in 12 watts a day?

A proper Solar controller will keep the PV voltage high where Maximum Power can be delivered with a matched impedance, while the DCDC converter reduces the voltage to manage the charge voltage with ...
Tony Stewart EE75's user avatar
1 vote

36V solar panel with a 12V battery, results in 12 watts a day?

5A rated means someone did some rating math at 5A. Check the charge controller specs. It may shut off if the panel voltage is too high ie would result in too much current to battery. Check panel Open ...
Abel's user avatar
  • 1,352
1 vote
Accepted

Are cameras' CCDs just elaborate tiny solar cells?

Yes, the actual light sensor in any CCD or CMOS imaging device is an ordinary silicon photodiode. However, there's just one silicon crystal (wafer), not an "array of silica crystals". Silica ...
Dave Tweed's user avatar
  • 6,914
1 vote

Are cameras' CCDs just elaborate tiny solar cells?

That is indeed the essence of it. CCD's either generate tiny charges upon being hit with light, or otherwise alter the accumulation of charges by the effects of light hitting them. They are made so ...
niels nielsen's user avatar
1 vote
Accepted

explaining ohmic loss and understanding inverter efficiency curve

I believe what this sentence is trying to convey is that all circuit components have a small resistance associated with them if you look at them in enough detail. For example a transformer circuit can ...
NMech's user avatar
  • 24.4k
1 vote

Joining the negative PV wires of 3 solar arrays for 3 MPPT controllers in an inverter?

Without seeing the inverter, if the maker provides 3 separate pv- then I would keep them separate. If they could be joined together, then the maker would have done so.
Solar Mike's user avatar
  • 15.9k
1 vote

How do multiple enphase microinverters stay synced to the grid?

A baseline grid-tie inverter samples the line voltage and produces current that is in phase with it and proportional to the maximum power it can squeeze out of the source (typically photovoltaic). So ...
TimWescott's user avatar
  • 2,682
1 vote

Design of Compound Elliptical Concentrator and Compound Parabolic Concentrator

Per the non-imaging optics wiki, C is the "ratio of input and output aperture areas". It is not efficiency like it is in some other equations. So putting a 45 degree half angle into the equation ...
ericnutsch's user avatar
  • 8,201
1 vote
Accepted

What is the purpose of the isolated subpanel terminal of a solar inverter?

I found out the answer. The isolated subpanel serves a load-center or distribution panel for backup loads (incase of power outage, etc).
Nagabhushan Baddi's user avatar
1 vote

Rotating Multiple Solar Panels with One Motor

I might go with a set-up use an offset arm to translate a long beam. Said beam has a link at each solar panel to a pole which push/pulls the panel to the desired angle. Kind of like the strings in a ...
Carl Witthoft's user avatar
1 vote
Accepted

Rotating Multiple Solar Panels with One Motor

You could consider idler sprockets to cause the chain to wrap around the drive sprockets more to increase the number of teeth in contact. the panels may move a bit due to play in the chain - tension ...
Solar Mike's user avatar
  • 15.9k
1 vote

Simulate Dust Layer on PV Cell?

More to the "even-distribution" question, I'd recommend your idea of water distribution. I'd use spray nozzles - they're designed for relatively even distribution. To that end, I'd recommend IS ...
Mark's user avatar
  • 5,333
1 vote
Accepted

Simulate Dust Layer on PV Cell?

A PV cell's system efficiency will vary exactly linearly with the amount of light blocked by the dust. For the particle sizes and wavelengths involved, refraction and multiple scattering effects are ...
Carl Witthoft's user avatar
1 vote

How can I add roof-mounted solar panels to a van without making it unstable at highway speeds?

I mounted 20 solar panels to the roof of my Airstream, which has a curved roof. I did this using two L brackets, attached together, then one attached to the panel, through the pre-drilled hole. The ...
Good Lux's user avatar
  • 111
1 vote

How can I add roof-mounted solar panels to a van without making it unstable at highway speeds?

There are a few different issues here. Firstly is the integrity of the frame itself. As well as the loads from the weight of the panels and aerodynamic drag it will be subject to fairly significant ...
Chris Johns's user avatar
  • 15.2k

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