For the last few years I have been using a 36v golfcart around here. This season, I am upping the ante with this rig...I am going to up its voltage to 48v, and mount solar panels on the roof. Its going to get an inverter, charge controller, and a storage box.
Last few years we have cut our fire wood with electric chainsaws...but this year is different, the wood is still piled out in the field...I think it would be more efficient to move the power plant out to the wood pile, so as to use the electric saws. Of course, there will be an ancillary increase in efficiency, involving moving ME away from the kitchen.
So the discussion I would like to have here is about 48volt equipment. I would like to find an inexpensive 48v MSW inverter in the 5000 watt range.
I would also be interested in some 48v MPPT charge controllers...
Rogue solar makes a decent mid range, full feature MPPT controller. (MPT-3048)
http://www.roguepowertech.com/ (http://www.roguepowertech.com/)
The MidnightSolar Kid is also a good one too.
Rogue, Morningstar, Midnight, Xantrex(Conext/Schneider-Electric), Steca, Blue Sky and Outback, all make reliable models of varied capacity and input voltages. Morningstar has no meters on theirs, it's an extra $100 for the meter instead of a blank panel. I have one (mppt60 & meter) .
Beware of re-badged, un-certified imports that merely have a label saying MPPT.
for electric motors, pure sine reduces power draw by at least 10% over mod sine, unless the motors are the brushed universal AC/DC motors. On pure sine, motors also run cooler. I like shopping at http://www.solar-electric.com/, they have a decent selection of inverters. 5KW is not going to be cheap. I run off a full feature 48V Xantrex (Schneider Electric) XW-6048 6KW
Can you use 2 inverters, one for each saw ? Or does your saw really need 5KW ?
Thx Mike for the links,
I have three saws...and I might as well review them here...I have the Husqvarna 316e which is the cadillac of electric saws...$300 with a 2 yr warranty..and you end up using it! The switches quit working on these saws. The good news is they are rebuildable and easy to change. $26 a pop, for switches.
The saw I use the most is a Remington 16" Versa saw...I think its 1650watts. Its $80.00 at Menards and for an additional $8, Menards gives you a 1 yr free replacement warranty. We cut 8 full cords last season with a Versa, before stripping the gears and taking it back to Menards and getting a replacement with no questions asked...
Finally, when all else fails I have an ancient Poulan electric that is painfully slow, 14" bar, cracked handle, but still works after 15 years. I paid $40 at Walmart for it, then. I don't recommend either the Poulan or the Husqvarna.
All saws are brush motors. All saws have worked on both MSW and PSW inverters, or real AC from generators.
It is entirely possible that the Versa will run on less then 5000watts...I run it on a Magnum 2812, and a "Kaching" Ebay 5K MSW inverter. It does equally well on both.
The constraints I am working around are: The Melex golf cart is originally 36volt, but the solenoids operate at 12v, and the motor control is entirely mechanical, so bumping it up to 48v is the only way to match the solar equipment to cart voltage....meaning, I got laughed at, when I tried to buy 36volt inverters, charge controllers, and panels.
The other constraint is more mechanical...namely that I am going to leave the cart out at the wood pile exposed to the elements, so I need robust components. I also need to be really good about the enclosure for the inverter.
I cannot imagine building a roof on the cart that could hold more then 4 Kyrocera 135w panels so, I am looking at a charge controller in the, less then 30amp range. Still you never know...if I built the roof like a kitchen table with fold up sides I might be able to double that wattage...although I have found that with a battery bank the size of the golf cart's 8, six volt T-105s, I can cut all day in full sun with 280watts worth of panels. Please read "cut all day" as several minutes of cutting and hours of lift and tote, putting the wood on the buck, and loading it in the trailers.
The caveat here is that I am going to test the melex on 48v pulling the wood trailer...I am looking for a little more "snoose" going up hills with the trailer. If it does do what I think it will, then I will begin welding the roof in earnest.
DF
Could your "kitchen table" folding panels be used in the fold down position as walls of sorts when not in use to protect the electronics from the elements?
Dear Brett,
Most definitely, and, during the spring, they will catch that last sun until 1030pm. I have always had that problem of getting the panels cranked around to the north during the last few weeks of spring and the first early weeks of summer.
How about re-thinking.
Leave the GC as is and use it for the tractor. Then you are free to build yourself a purpose built trailer/ Power Station. It can then be, the bat bank, solar support, and inverter house. You could go as far as building it to IP-68 folded up or out. You might even armor it, depending on the neighborhood, and how often you visit the woodpile.
Use your tractor/GC to tow it to the wood-pile, and leave it.
Lloyd
Quote from: Dualfuel on March 18, 2014, 04:52:10 AM
Thx Mike for the links,
I have three saws...and I might as well review them here...I have the Husqvarna 316e which is the cadillac of electric saws...$300 with a 2 yr warranty..and you end up using it! The switches quit working on these saws. The good news is they are rebuildable and easy to change. $26 a pop, for switches.
The saw I use the most is a Remington 16" Versa saw...I think its 1650watts. Its $80.00 at Menards and for an additional $8, Menards gives you a 1 yr free replacement warranty. We cut 8 full cords last season with a Versa, before stripping the gears and taking it back to Menards and getting a replacement with no questions asked...
Finally, when all else fails I have an ancient Poulan electric that is painfully slow, 14" bar, cracked handle, but still works after 15 years. I paid $40 at Walmart for it, then. I don't recommend either the Poulan or the Husqvarna.
All saws are brush motors. All saws have worked on both MSW and PSW inverters, or real AC from generators.
It is entirely possible that the Versa will run on less then 5000watts...I run it on a Magnum 2812, and a "Kaching" Ebay 5K MSW inverter. It does equally well on both.
The constraints I am working around are: The Melex golf cart is originally 36volt, but the solenoids operate at 12v, and the motor control is entirely mechanical, so bumping it up to 48v is the only way to match the solar equipment to cart voltage....meaning, I got laughed at, when I tried to buy 36volt inverters, charge controllers, and panels.
The other constraint is more mechanical...namely that I am going to leave the cart out at the wood pile exposed to the elements, so I need robust components. I also need to be really good about the enclosure for the inverter.
I cannot imagine building a roof on the cart that could hold more then 4 Kyrocera 135w panels so, I am looking at a charge controller in the, less then 30amp range. Still you never know...if I built the roof like a kitchen table with fold up sides I might be able to double that wattage...although I have found that with a battery bank the size of the golf cart's 8, six volt T-105s, I can cut all day in full sun with 280watts worth of panels. Please read "cut all day" as several minutes of cutting and hours of lift and tote, putting the wood on the buck, and loading it in the trailers.
The caveat here is that I am going to test the melex on 48v pulling the wood trailer...I am looking for a little more "snoose" going up hills with the trailer. If it does do what I think it will, then I will begin welding the roof in earnest.
DF
I'm working, OK playing with a 36 volt Cushman golf car (notice no "t"). One of the manuals I have pulled off the Net recommends bumping it up to 48 volts. Everything should work better says it. So I'm faced with replacing the 36 to 12 volt thing with a 48 to 12 volt thing. I wish I had popped the extra $11 for the 24-60 to 12 volt thing now that I'm faced with going to the 48 volt common denominator world. Those of you that know me realize I'll run what I got until it smokes and then replace it with the correct thing. And yes I've attended the lectures about how much power there is in three or four 12 volt lead acid batteries.
Curiosity questions. If it's a mobile battery station then why is it being left out? Where are you that the June and July solar angles make that much difference? (You're cutting fire wood so I assume you're North of the tropics.) Wouldn't two 250-270 watt panels be a lot better than four 135 units? Wouldn't it be better to leave these saws running between cuts as much as possible to reduce current flow and extend switch life?
Casey
PS.
Dear Llyod,
The cart tows the wood trailer....if it runs out of power, I would be able to just leave it. As it is now, I have to charge it at the oil shed with its solar system, and limping back on dead batteries is a PITA, much easier to dismount and wander off in an ADHD moment, and come back to find the cart charged.
Armor..ha ha...they cut ALL the trees down, no need for armor anymore...I sure have had my fair share of stuff smashed by trees though...
Dear Casey,
The cart is either parked outside at the wood pile or at the camp...the cheapskate in me says walk my fat a$$ down the hill to the camp for lunch rather then drive.
I am north of 48 latitude...for June and July the sun at noon is more north then overhead.
That is good to hear about the switch from 36 to 48...I suspected as much, because I put a voltmeter on the cart and watch it at various accelerator settings...and its not uncommon for the batteries to be down to 5v if you floor it..
DF
Quote from: Dualfuel on March 19, 2014, 05:46:36 PM
Dear Llyod,
The cart tows the wood trailer....if it runs out of power, I would be able to just leave it. As it is now, I have to charge it at the oil shed with its solar system, and limping back on dead batteries is a PITA, much easier to dismount and wander off in an ADHD moment, and come back to find the cart charged.
Armor..ha ha...they cut ALL the trees down, no need for armor anymore...I sure have had my fair share of stuff smashed by trees though...
DF
That's why I said re-think IT!!!!
Under my plan you have two trailers, and one GC/cart/Tractor.
Now tow the purpose built Power trailer to the wood pile. Now this trailer is the POWER Center. So it holds your, bats, inverters, and solar panels. So now you have a charging source at the wood pile, for the saws as well as the GC/cart/Tractor. As well as the one at the shop.
The armor is only to stop the would be thieves, from departing you of your duly needed electrical components, that makes the Power Station valuable, at the wood pile.
Note second trailer, is for hauling the wood.
Lloyd ;D
QuoteI am north of 48 latitude...for June and July the sun at noon is more north then overhead.
I need some help here. I'd do it myself but I don't know how to ask google.
I thought the sun was only 90 degrees or greater in the two tropic zones?
At what deflection to the sun does a solar panel start declining in measurable power? Is it linear?
Casey
Dear Casey,
There are two imaginary lines...the tropic of Capricorn and the tropic of Cancer...today, first day of spring, the sun is 90deg to the surface of the earth halfway between the northern tropic, and the equator.
Dear Lloyd,
Ok got it...two trailers. Will have to think and look at my junk pile...The enclosure doesn't have to withstand thieves...but nature is pretty fierce here.
Duelfuel,
I think you need to check this page out.
http://www.geog.ucsb.edu/~joel/g110_w08/lecture_notes/sun_angle/sun_angle.html (http://www.geog.ucsb.edu/~joel/g110_w08/lecture_notes/sun_angle/sun_angle.html)
Casey
Hi DualFuel
Old thread but I've been off MCG a long time.
Your wood cutting needs will still be the same.
Interesting you critique on the Husky electric. Who'da thought.
Gifted my then 82 year old father-in-law a Stihl MSE 180 back in 2005 for woodshed limb blocks splitting. HARD Use! Blocks ripping to get down through 6" hard dense limb roots. His only problem was tooth breaking on the original set up pico chain. 2nd year swtiched it to standard 3/8" chain and that stopped. Better chips/strands anyway for the chicken litter and woodgas filtering. Powerful electrics start at full power/torque with no give at all. He used this for three years until his death. I used another year until brushes worn. Light show/ozone smell. ~100 hours loaded using. Still have the saw with new brushes.
Nothing broke.
I'd say these are The "Cat" of electric saws. For a "Cat" price and worth it.
The new 36 and 48 volt battery pack saws look too light of cycle duty to me. I said pass, thank you to the saw shop guy. But an option to try and direct power.
Regards
Steve Unruh
I also have a 36V cart and have been considering a similar project for a while now. I think I am going to go with a power trailer instead of putting it on the cart itself. My cart has a pick-up type of bed and tailgate and no roof. I like the idea of being able to set the mobile power rig where I need it and then still be able to use the cart. Also it leaves the extra load of batteries detachable and panels and toolbox detachable. I have a couple of areas where the brakes wouldn't handle a full load of firewood and the extra batteries and such. I also plan to be able to easily connect the cart motor to the trailer if you need to.
I may go 12V just because I have an old trace 2512 that is a beast. It is reated for 2500 but will actually do far more. Runs a welder fine. I would like to go 48V on both, as my motor and controller could handle it. But then I'd need a new inverter and charger. So I may be stuck with 12V.
Jonathan
I still can't take it. Seattle has a latitude of nearly 48 degrees. Trust me! The Sun does not get 90 degrees or more to surface of the surface of Puget sound.
How goes the 48 volt conversion? I should have mentioned my cart components are of the early style and rely on resistance to modify the voltage to the motor.
Casey
Ha! Casey,
The cart is coming out of the snow and I am low on gas so....am definitely reviving this project. Still have not found a good 48volt charger or alternator. Still its worth going for it.
Hi Dualfuel, (Corrected Grammar)
I'm still here. I'm still interested in your project. I winnied out and went 36 volt because I'm sticking the batteries onto a Polaris ATV and a fourth battery would have to be much higher and mess with the center of gravity. (the farm raises almost 300 feet in less than 800 lineal feet = serious slopes.)
Oh, we just cruised through equinox and the sun was still South of 90 degrees. We're at 19 degrees latitude. http://en.wikipedia.org/wiki/19th_parallel_north (http://en.wikipedia.org/wiki/19th_parallel_north) and http://en.wikipedia.org/wiki/48th_parallel_north (http://en.wikipedia.org/wiki/48th_parallel_north) and https://www.google.com/?gws_rd=ssl#q=tropical+zone+definition[/url].
I wish the 36 to 120 inverters were as cheap as 48 to 120 inverters.
If you have an electronic voltage controller you should contact someone that is familiar with their power requirements and limits.
Cheers,
Casey
I will get out the compass and lay out an east-west line to see whats going on. I do notice the sun is coming in the windows on the north side of the camp.
I have the solenoid and resister controller on my cart as well. Its an old Melex (polish). I found that 36v inverters were just not available. 48v inverters seem to be the size that provides the wattage that is high enough to be useful in the field.
I have those brush piles to cut, with the electric saws, so its a lot of short cuts and setting down the saw, which is perfect for an electric.
Wow! You are south of the tropic?
Aloha Dualfuel,
QuoteI do notice the sun is coming in the windows on the north side of the camp.
I'm sorry but you need a compass for sure. At noon, when your facing the sun; you're facing South. I'm Seattle, really close to 48 degrees, and I'll do this test today myself.
Cheers,
Casey
PS: I found South in Kona by looking at the sun directly at noon in December. Again, at 19 degrees and the sun isn't at 90 degrees yet. I check this with the roof overhang and the shade line.
Solar panel on rood will make precious little difference to the range. How many KW hr of power do you think a roof mount PV panel will generate?
Buickanddeere,
The panels, if mounted on the cart, will produce the same kw-hr that they presently do, mounted on the building. The big advantage of mounting all the solar paraphernalia on the cart, is now the power plant can move to the wood pile, instead of loading the wood on the logging truck and driving it to the building.
Casey...ok ok, I WILL get of this comfy chair and go measure right now, as the sun IS shining in the north window, just after dawn. I will get some data for you. LOL!
Casey...I used a lensatic compass and a GPS...at dawn the sun is coming up directly east 90degrees. The stupid camp is NOT oriented along an east west line but rather the west end is slightly northwest of the east end (hence the sun in the north window).
Heyyyyyyyyyyyyyyyy,
High noon! The change in azimuth is less influenced at the East and West as it is at the center of the path.
I'm in Seattle and the sun just ain't atop my head when it's noon. That's the optimal time for solar generation. This thread is about solar generation isn't it? Before 9 AM and after 3PM are less than 25% of my total daily collection (on average).
Of course Buickanddeere's car mounted panels would allow for hourly optimization. ;D
Oh well, I've got an extension to file.
If it ain't an art project or I'm not having fun; Just what the Hell am I doing here?
Cheers,
Quote from: Dualfuel on April 14, 2015, 05:44:39 AM
Buickanddeere,
The panels, if mounted on the cart, will produce the same kw-hr that they presently do, mounted on the building. The big advantage of mounting all the solar paraphernalia on the cart, is now the power plant can move to the wood pile, instead of loading the wood on the logging truck and driving it to the building.
Casey...ok ok, I WILL get of this comfy chair and go measure right now, as the sun IS shining in the north window, just after dawn. I will get some data for you. LOL!
How long do you think it will take for a roof mounted solar panel to charge the golf cart's battery bank ?
BuickandDeere,
The charging question's answer, can vary greatly. My sense is you wish to pin your skepticism about the project on some number. Before we go there, let me explain what is already happening.
I have three panels, whose wattage I forget, mounted on the oil shed. The oil shed has a 5000 watt inverter, and enough deep cycle storage to run the pumps all day. I have had this system working in its present configuration since 2006. When I got the golf cart, I set up some long jumper cables and started charging the cart with the oil shed power, 2 105s in series at a time.
All armchair BS aside, if I mount all the oil shed solar equipment onto the cart, I expect everything to be the same, except that the powerplant in sort of portable. If I am cutting wood up on the ridge, I expect to get even more power, by keeping the panels in the sun even longer then their present location.
At present, the charge controller stops charging the batteries at about 10am. After that, the power is wasted. I used to bring the logging truck down to the oil shed and leave wood down by the oil shed for cutting after breakfast. I think it better, to take the saw, etc., to the wood pile, or take the powerplant to other projects, so I do not have to listen to the Honda droning on, all day.
Soooo, to answer the question...lets say I have no more then 300 watts worth of panels on the cart. Lets say I am charging two cart batteries at a time. Lets say I am busy and do not have any interest in checking to see when the two batteries are actually charged, so I come change the configuration once a day. Knowing that, I would say it would be three days for the cart batteries to be fully charged (the caveat being, full sun for those three days, of course).
I realize this seems inefficient. Its not. There will be a minimal monetary capitalization to get this set up. The portable configuration allows me to use wasted power in a variety of locations.
Could the efficiency be better? Oh heck yes! Efficiency comes with a price though, a price I cannot presently pay. So it is what it is.
Hi DualFuel,
I'm back - in two ways. I'm back on your thread and I'm back in paradise on the 19th parallel. Yesterday at 11:40 the Sun was still below the 90 degree azimuth. I'm guessing mid-May we'll go 90 degrees. That gives a month of past 90 degree solar radiation here in the tropics. "The Topics" is that make believe place where myth has it that at 8 AM it's Sunny and 70 degrees.
I have a neighbor with a charging ASSISTED solar panel on the roof of his Club Car. - factory unit of about 180 watts - single panel. He isn't doing much more with his car than it sounds like you are. Certainly nothing close to 18 or even 9 holes of golf on any given day. He sticks it on the factory charger every once in a while to top up the batteries or if it struggles up his driveway which is not really that steep. He gave me a "deal" on his 36 volt cart and I think I know why. This is one of them newfangled '98 models with the electronic voltage controller so I'd have to spend a couple of hundred dollars to upgrade to 48 volts.
Charging batteries separately that are part of a string sounds like a bad date with destiny. I'm not saying I wouldn't do it exactly the same way as you if it were working for me. I just thought I'd mention it for those manual readers among us.
Keep you eyes pointed North and don't worry about the sun block.
Cheers,
Casey
It happened sometime this week. I checked on Cinco de Mayo and then yesterday and sometime in that week the sun's rays started striking our farm at 90 degrees. So we'll have about six weeks before and six more weeks after solstice. Remember the rays move from 23.5 degrees North to 23.5 degrees South during the course of a year. And if you're farther away from the equator than 23.5 degrees North you ain't going to see the sun straight up when your facing South.
Casey
Yep Casey,
The sun now rises to the north. I have to turn the panels to the north to catch the first four hours of light. About 10am I have to turn the panels overhead and to the south. About three I have to turn the panels back to the west and north for the remainder of the day.
Progress
So far I have a bench proof of concept circuit setup and am now looking for high amperage switching. I have the charging circuit setup comma and the hardest part left to do is the welding.
Looks neat but I don't understand the switch layout. Can you do a switch schematic for me? Double pole and six wires has me challenged besides spending too much time getting the back of my head bombarded by ultraviolet whilst facing South at noon. ;D
Casey
(https://www.iesve.com/software/images/ve-pro/modelviewer2/solar-arc.png)
Casey,
I better start with old news first, as you still seem to be confused about how the Sun appears to travel across the sky. The image posted above , shows how the Sun crosses the sky. For us, the end of the arcs, where they intersect the Earth travel northward until the summer solstice, and then they begin to travel back to the South until the winter solstice.
If you care to Google weather for Calumet 49913, you will see that our solar noon takes place at 1:50 p.m. so if you were here facing south at 12:00am you would indeed have the sun shining on the back of your head.
On to new business, I sympathize with your inability to visualize the circuit. That has been the same problem I had while trying to draw a schematic. I had too many lines running too many different places for it to work easily in two dimensions. I discovered it was easier to draw in three dimensions, or visualize the circuit in three dimensions. To do so simply place the dpdt switches in the center of an axis. Place the batteries , the inverter, and the motor around the axis, 120 degrees apart. From there it should be fairly easy to visualize 2 leads going from each component to the dp/dt. Truly, the only trick is visualizing the series circuit to the motor.
The next most complicated part, will be installing 6 volt batteries and wiring them to this configuration.
DF
DF,
Here's a schematic I did for switching my three 12 volt batteries from 12 volts to 36 volts output back and forth with some consideration for balance and battery life. I have a 12 volt 1500 watt inverter and 36 volt inverters are very expensive. But then so are three way battery switches. And switches do attenuate low voltage DC. I considered using the resistance switch in my cart circuitry to weld with too. So many ideas (dreams) and so many, many, many "OTHER" chores on a farm.
Forward to the same news - I grew up in Seattle which is not too different from the Calumet latitude (about 47 degrees). You cannot face South and ever have the Sun strike the back side of your back side. Obviously, One of us is blinded by the light. ;D
Casey
Mr Casey and DuelFuel what is interesting to me is you both have "farms" with spread out need-power locations and are working toward a mobile battery bank power solution.
Ha! Same needs-power out-and-around, dilemma as me. Over 1600 feet from the one corner of our property's 195 foot deep well to the opposite corner where 200 baby fir tree went in this Spring. Damn late June-type weather in April now early May has had me bucket carrying water now daily to these rain loving DF trees. How 19th century.
This family farm evolved from the 1930's on-Grid making for up to FIVE power-in meter locations in the past. Bad habit taking the cheapest easy way outs. County roads two sides wrapping; and a third side road Grid power touched.
I've got it down to only three meter-in locations now. And since May 1 have been inverter-generating for the one to the freezers/four bay wood/tool shed location. I Grid-lite here to the two houses. But insist now all out locations are DYI off-grid. Good practice. And practicing every day now when needs-must Grid-Downs (as happens here up to 9 times a year from 20 minutes to 3 days here) then I know my working solutions WILL WORK immediate-needs, come hell, high water or the second coming.
My point is I too have many urban/suburban around the world living friends now with 2.5-5.0 kW home systems: IC engine, micro-wind, micro-hydro, PV battery banking wonder what all of my fussing is about point making power now instead of trying to central battery bank distribute my DIY out.
Mini-home-Gridding past 300 feet sucks big-time. Efficiency's. And out-of-pocket Bucks
Ha! On your sun shining stuff turns out you are both kinnda correct.
I am 150 miles south of See-Rabble.
10:00 AM to 2:00 PM no-way, no-how is that damn sun gonna ever shine on the back of my male pattern bald spot.
Sun up at 6:00 AM to ~9:00 Am: then 4:00 PM to sundown ME facing south it will. Broad brimmed hat time. Too keep that the low angle glares off the back of my neck.
Take a stand globe. Tilt it correctly. Push pin your location. Set up a focused stand off light source as the sun. Rotate the globe. You will see.
Keep up the good interchanging. And use-proof DO'ings.
Best Regards
Steve Unruh
Aloha Steve,
One word - "Garden Hoses"! ;D
The transfer of energy need not be on copper conductors. Our "Menehune Energy Lab" (MEL in respectful remembrance of HAL) is both a water catchment/storage building and also a solar array / inverter station house.
Yeah, I noticed the parallel universe stuff too. You forgot Bull Headed or you're too nice to be a member of the club. So are we brushing our teeth here or collecting solar energy?
Cheers,
Hey Mr Casey
Pump/flowing water or liquids is almost exactly the same a DC distancing electrical power.
Flow-lossXdistance.
175 feet UP from the deep well pump through a 2 inch poly pipe. 1 1/2 inch poly pipe 100 feet to the Folk's small 1959 house. Then another 150 feet in 1 inch poly to our smaller lived in remodeled 1906 house.
From there I was only able to make it out another 300 feet in 3/4" garden hoses from the well corner of property to opposite corner to reach with "caint hardley" usable flow/pressure with an additional grooud up sloping gain to fruit and nut trees I tried to put in back in 1997.
Deer like them better than I was able to protect them. A five year tussle. They won.
1800 feet across and with a total ~100 foot ground sloping up gain I'd need 3" piping and at least a 3 horsepower pump to get meaningful full flow/pressure.
DC current in 12-32 volts above one kW as Duelfuel well knows too, and you start needing big 00 and 000 cabling past 100 feet. Gets super 'spensive.
Why aircraft use higher voltages and frequencies. Saves weight.
Past the fun of sun-on-back-of-your-head funning,
what he is trying to say is most flat-plate fixed folks are leaving a lot of solar-hours on the table unharvested.
Even active tracking folks never getting that first three hours and last four hours without enough horizontal and vertical range of sweeping.
So how he can make his little 300 watt array outperform the much larger, more expensive is by active hands-on mobile management.
Plus . . . mobile, smallish come a hail storm, tornado, hurricane winds and you can run for cover and save it. Cheap.
Steve Unruh