WAIT a minute. That paper is about hydrogen-doped
amorphous/nanocrystalline silicon. It's been known for decades that
doping with hydrogen causes amorphous silicon to adopt a
nanocrystalline structure.
If that's the evidence, then I think the jury is still out on pure
amorphous silicon.
Yep, there are many observations we can't explain because we can't yet
measure well enough at the atomic level, especislly below the surface.
That's why I objected to your blanket statement that amorphous silicon
has no nanocrystals, in practical mass production versus by
theoretical definition. I suspect the solar panel makers don't waste
the time and money to check for them, and I once built semiconductor
automatic test equipment for Teradyne and was a lab tech at Unitrode.
https://en.wikipedia.org/wiki/Staebler%E2%80%93Wronski_effect
My amorphous Harbor Freight panels will barely reach 0.6A instead of
the 0.86A they are rated for. When I bought them I didn't have the
test equipment to measure their maximum power point so I don't know if
they met spec even then. No one offered a better kit at a local store.
The surplus monocrystalline panels have degraded in reverse leakage
current but not output. At noon they were pushing 85W into the battery
according to the power meter.
-jsw
On Monday, November 23, 2015 at 9:41:50 AM UTC-5, Ed Huntress wrote:
I think there are still amorphous solar cells around. The solar cells in calculators were pretty much all amorphous cells. Cheap, not too efficient, but adequate for calculators.
Dan
On Mon, 23 Nov 2015 11:12:20 -0800 (PST), " snipped-for-privacy@krl.org"
Yes, looking around, I see that's one place where they're still used.
There also are a variety of experimental multi-layer thin-film cells
that contain a layer of amorphous silicon, and which have much higher
efficiency. Sony has made some, and there is a large installation of
them at an agriculture station somewhere in NJ.
The problem Sony had with theirs, initially, was relatively short
life. I don't know if that's still the case.
No crystal shape but a crystal. Likely a translation from xxxx to English.
And missed.
Some experimentalist make it out of plastic and other materials.
Martin
On 11/22/2015 11:27 PM, Spehro Pefhany wrote:
I went out and added a battery to the array and hooked up the
inverter. It runs the electric chainsaw just fine, thankfully.
It's all boxed back up for the winter now.
--
The most powerful factors in the world are clear
ideas in the minds of energetic men of good will.
I'm OK with the original PWM ctrl on the HF array, but after reading
what MPPT can do with arrays wired at 24v or more, I definitely want
one for my larger array when I get it. I'm on the fence between a
Taiwanese brand and an Outback, either 60 or 80A models for the
possibility of additional panels in the coming years.
--
The most powerful factors in the world are clear
ideas in the minds of energetic men of good will.
Picked up one of the little $13 AODE aluminum-cased wattmeters you
mentioned last time, thanks. It works well.
I can't stand wood heat, but may when the SHTF. Need to buy one of
those little guys for $60, JIC. http://tinyurl.com/qdvp8lt
Does anyone _like_ the smell of wood smoke in the house? Then again,
having heat would be A Good Thing(tm), if the natural gas goes out. I
wonder if they keep generators for the nat gas pumps, and how long
they'd last once the pumps quit, if not. Delivery pressure is 1.5psi,
so it may last a long while.
--
The most powerful factors in the world are clear
ideas in the minds of energetic men of good will.
Don't trust the least significant digit of the Amps readout. Mine
actually resolves to 0.2A and fakes higher sensitivity by dithering
the raw value. The wires are too small for its full-scale Amp
capacity. Otherwise it's a very handy gadget for checking and
reconditioning older batteries.
http://www.artecing.com.uy/pdf/guias_megger/New%20-%20BatteryTestingGuide_en_LR.pdf
I've found a DC resistance check while periodically topping off a
battery to be a good, quick indication of when it needs attention. I
haven't found a good Net reference to this yet, all descriptions of
battery impedance testing I've seen are from companies trying to sell
fancy equipment for it, just like desulfation.
The Bayite meter is more suited to a fixed installation, with the
shunt in the battery cable and the readout at the control panel. I
added a DPDT switch to reverse the (fused) shunt sense leads so it can
read either charge or discharge current. My inverter is an APC1400 UPS
which can draw over 50A continuously, probably too much for the Aode's
wires.
A properly installed and operated wood stove doesn't emit smoke into
the house, all leaks draw air in. I've learned how to set the draft
for complete combustion with little or no visible smoke from the
chimney.
That wasn't easy. I have thermocouples on the basement stove with
readouts in the kitchen and bedroom and an outdoor mirror plus a night
vision camera to observe the chimney top. It's very convenient to know
when to tend the stove or the food cooking on it from upstairs.
These are cheap and good enough if you can't find (and fix) surplus
lab instruments as I did.
(Amazon.com product link shortened)
-jsw
I guess I'll have to remember to crank the draft wide open to load
firewood, but I've never seen a house yet whose wood stove didn't blow
smoke into it, regardless of settings. <shrug>
Hah, that's cool! Self-surveilled. Are those remote t-coups?
I have a thermocouple available with my Mastech DVM.
--
The most powerful factors in the world are clear
ideas in the minds of energetic men of good will.
I can't say my stove -never- smoulders, catches and backfires but it's
rare. Lighting it may be smoky until the cold draft down the chimney
reverses. Burning one sheet of crumpled newspaper in the upper chamber
is usually enough to get the air flowing up long enough to light the
kindling.
When the stove is up to temperature the draft vacuum runs between 0.08
and 0.15 inches of water, enough to make the air inlet whistle.
(Amazon.com product link shortened)
I can remove the cleanout cap in the inside flue pipe without
releasing smoke into the house.
I found spools of cheaper thermocouple extension wire at the surplus
store and ran them from the stove in the basement to the kitchen and
bedroom.
http://www.awcwire.com/productspec.aspx?id=pvc-single-pair
The X indicates extension wire which matches real thermocouple wire
only near room temperature.
The dollar a pound price for regular wire was better than a dollar a
foot for real thermocouple wire. Omega charges only a little more for
high-quality new wire:
http://www.omega.com/pptst/XC_K_TC_WIRE.html
These panel jacks
http://www.omega.com/pptst/MPJ.html
snap into these wall outlet faceplates with only a little trimming
https://www.computercablestore.com/12-port-keystone-faceplate-dual-gang-white-3
If my Tekpower DVM is like it the cold compensation isn't exact and
the linearization is incorrect. The PC datalogging program corrects
the linearization and shows a difference from the meter's display. The
error is only a few degrees C. When I log the house's heating or
cooling rates I record a few temperature points and times from the lab
instruments for calibration correction. They read within 1 degree C at
freezing and boiling regardless of room temperature.
-jsw
I've always done the wadded paper at the chimney trick to get the
smoke drafted up that way from the start.
Har, he even measured it! <g>
(Yup, Gadgaholic) I guess my old automotive vacuum gauge won't cut it.
Cool.
For K t-coup wire?!? Seems way heavy.
Ensuring a Kosher and clean setup.
http://tinyurl.com/ofygs9s $4.56 delivered.
I think Tekpower bought them, so they're probably nearly identical.
If and when I get into datalogging (most of the new MPPT controllers
have that capability), I'll remember this.
Now that I'm retired, I have all sorts of projects lined up and ready
to go, and I'm gaining the time to get around to them. You're NOT
helping. <vbg>
--
The most powerful factors in the world are clear
ideas in the minds of energetic men of good will.
On Saturday, November 21, 2015 at 4:49:43 PM UTC-5, Larry Jaques wrote:
My wood stove has an opening such that I can use a small propane torch to preheat the air in the chimney. So I do that and then close that opening and use the torch to light the kindling. I refill the 16 oz propane tanks from a 20 lb cylinder.
Dan
On Sunday, November 22, 2015 at 6:57:11 AM UTC-5, Jim Wilkins wrote:
I have bought a number of small propane torches at garage sales. So when I
refill a tank, I put a torch on the tank. So no problem with leaks.
And I do not mess with the relief valve. To refill a cylinder, I put the c
ylinder in the freezer and refill after the cylinder is cold. If the tank
is completely empty, I may have to cool it and refill it more than once. B
est to do this when the cylinder is about 1/4 full. The steel tank does no
t have much thermal mass.
But to answer your question, yes I have had refilled cylinders leak.
Dan
On Sunday, November 22, 2015 at 6:57:11 AM UTC-5, Jim Wilkins wrote:
I have bought a number of small propane torches at garage sales. So
when I refill a tank, I put a torch on the tank. So no problem with
leaks.
And I do not mess with the relief valve. To refill a cylinder, I put
the cylinder in the freezer and refill after the cylinder is cold. If
the tank is completely empty, I may have to cool it and refill it more
than once. Best to do this when the cylinder is about 1/4 full. The
steel tank does not have much thermal mass.
But to answer your question, yes I have had refilled cylinders leak.
Dan
=============I bought the adapter fitting and extension hose but haven't used them
yet. Now might be a good time since the weather is 50's during the day
and 20's at night. I could insulate the big tank with bubble wrap to
retain the day's heat and let it fill the small one outdoors
overnight.
-jsw
https://en.wikipedia.org/wiki/Compressor_station
"A small portion of natural gas from the pipeline is burned to power
the turbine."
"Commonly known as "recips," these engines are fueled by natural gas
from the pipeline."
I never investigated how reliable or susceptible to sabotage the gas
lines may be. Electricity on poles is demonstrably vulnerable but easy
to repair. Our ice storms and distracted drivers keep the crews in
practice.
My automatic backup is the house's original baseboard electric heat,
set to come on at 50F. I have these on the wall thermostat wires to
warn me if they turn on or I forget to set the bathroom back after
showering.
(Amazon.com product link shortened)
In an unlit hallway the LED is visible at a much lower current than
they list. There's no sharp 'turn-on point", they just get brighter as
the current increases.
-jsw
Transformers are far too susceptible to sabotage, too, especially
"hidden" behind chain link fences.
I ripped all those out in 2002, less than 2 weeks after I moved in
this house. CROM, those suck. 40F floor, 65F in the middle, and 90F
at your head when you stand up, all while sucking 4kWh per unit. The
96% efficient HVAC cost me $6k, but it blows the air around and keeps
everything mixed so the temp at the floor is the same at the ceiling,
more or less. I like to stand under the vent when I come in from
outside in the winter. How can you stand baseboard heat, especially
when it's not on PV to pay for it?
I guess with -those- heaters, you can save money and buy the 1AAC
setpoint units for the least cost. And each probably shines bright
enough to light your whole house. <g>
I see that you're a fellow gadget freak.
--
The most powerful factors in the world are clear
ideas in the minds of energetic men of good will.
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