OAUSA Net - September 10, 2020 - Alternate Power in the Wilderness I & II

A preview of future nets
User avatar
Site Admin
Posts: 3543
Joined: Tue Mar 11, 2008 10:33 am
Call Sign: K6DTK
Location: Southern California

OAUSA Net - September 10, 2020 - Alternate Power in the Wilderness I & II


Post by DaveK » Sat Sep 05, 2020 11:55 am



Like many of our other topics, this one required more than one session to cover the essentials. For those who camp and who want some of the comforts of home, without adding much bulk to your camping gear, alternate power is the answer. Join us for the conclusion to this topic.


Well, this year the camping season got a little weird due to the Wuhan. First, campsites were open, then they were closed, then they were open again (sort of.)

Even when open, there is a dizzying mix of rules and regs that dictate how we are to enjoy the outdoors. The real culprit however, seems to be the effect to which the public, in general, is scared to death of catching the virus. In spite of all this, there seems to be no way that the rulers of the kingdom can stamp out our need to get away, and enjoy the outdoors. So, for all you that are brave enough to get out, Its time to go camping. We hope that tonight's net will help all the campers out there to make the most of their outdoor time.

Like it, or not, electronics have crept into almost every corner of our lives, and that means that we need power to make these gadgets work.

For just about everyone who listens to these nets, we are already hooked on the various Ham radio gadgets that we use at home and on the trail. But, that's just the start. Wilderness travel requires that we also need to find a way to power what seems like an ever increasing number of devices that also require power, like:
  • computers
  • GPS units
  • handheld transceivers (HTs)
  • inverters
  • air compressors
  • air pumps (air mattresses)
  • battery rechargers (flashlights, radios, headlamps, lanterns, etc
  • APRS
  • refrigerators
  • and of course, Ham Radios
Everything is great, as long as the vehicle is running, but when parked at camp, with no motor running, the combination of all of these toys can drain a battery in a big hurry. Multiple options now exist to help you power all your camping and wilderness needs.

Our discussion during the net will be directed to they types of activities that we normally enjoy. With that in mind, here are some important limitations that you will need to consider.
  • For the large majority of our adventures, we are vehicle dependent, meaning that our vehicles must have sufficient room for the gear that we bring, and that certainly includes alternative power items. Knowing how much room you have will determine what you buy.
  • Speaking for my self, there is one factor that really deserves some thought - camp set-up and take down. There is no getting around the fact that one of the less enjoyable tasks of camping is getting camp ready and then putting it away. We are always thinking of ways to make these two tasks quicker and easier. For alternative power, having the most extensive and sophisticated set up is great, that is until you are the last guy to wrap things up when the group is waiting to move on to the next destination.
  • Quality, quality, quality!!!! There are two components to this one: 1) buy good stuff and 2) buy American.

Extremism in the defense of liberty is no vice.
Moderation in the pursuit of justice is no virtue.

User avatar
Posts: 296
Joined: Thu Apr 18, 2013 8:32 pm
Call Sign: KK6CTT
Location: SOCAL

Re: OAUSA Net - September 10, 2020 - Alternate Power in the Wilderness


Post by lrsrngr » Wed Sep 09, 2020 7:19 pm

KK6CTT for the online check-in, 09/10/20. Thanks OAUSA net control. Great job Paul! Awesome explanation.

To help others with questions concerning new technology (lithium batteries) tune in with Will Prowse: https://www.youtube.com/user/errolprowse

I just started throwing things together and it looks like I might have got a few things right based on your research! My budget build over several months of working through things and collecting pieces over just as many months. I have also dabbled in some smaller scale systems that have served me well both in the EMCOMM world and family camping (low-draw) world. Solar has been the base of all my systems along with 12v lighter socket jumpers used to top the system off while driving from time to time.

This is the Big Boy who helped provide power at the 2020 Field Day with the local club when some other equipment failed. It was overkill but it definitely met the needs of the group with respect to charging and radio power distribution.

190622, FD Large Battery Box 640 01.jpg
Large secondhand Rubbermaid box, non-conductive and able to handle two 75AH AGM batteries.
190622, FD Large Battery Box 640 01.jpg (57.87 KiB) Viewed 482 times

190622, FD Large Battery Box 640 02.jpg
Auto/marine style fused distribution center as opposed to the more common Anderson power strips.
190622, FD Large Battery Box 640 02.jpg (83.03 KiB) Viewed 482 times

190622, FD Large Battery Box 640 05.jpg
On the left side of the box I have these receptacles available.
190622, FD Large Battery Box 640 05.jpg (80.52 KiB) Viewed 482 times

Battery Bank 800 04.JPG
A 120-watt semi-flexible panel held in a PVC pipe frame with adjustable legs that can be oriented either horizontally or vertically.
Battery Bank 800 04.JPG (123.57 KiB) Viewed 478 times

Battery Box Large 640 01.jpg
1500-watt sine wave inverter used to power our refrigerator for a short period of time as a test of the system where the solar panel will probably lose ground but good for a short time.
Battery Box Large 640 01.jpg (108.15 KiB) Viewed 478 times

Here are some smaller scaled down versions to include the most recent LiFePO4 battery experiment (Bioenno does not recommend putting their batteries in parallel):

200322, Bioenno Battery Box 640  01.jpg
It is recommended by Bioenno not to place the batteries in parallel but obviously I did not get the memo on that and have been using this in experimental format. So far, so good.
200322, Bioenno Battery Box 640 01.jpg (65.27 KiB) Viewed 453 times

200322, Bioenno Battery Box 640 02.jpg
Two 9AH batteries in parallel. I have since added a solar power input from a Renogy solar charge controller with LI capability.
200322, Bioenno Battery Box 640 02.jpg (59.47 KiB) Viewed 453 times

200322, Bioenno Battery Box 640 04.jpg
I went soft case on this one. This is a CD case found at a thrift store with a little padding for protection and room to put extra connections and accessories.
200322, Bioenno Battery Box 640 04.jpg (88.61 KiB) Viewed 452 times

200322, Bioenno Battery Box 640 05.jpg
Proof of weight differences and getting more power with the same weight is huge for individual or vehicle load planning weight.
200322, Bioenno Battery Box 640 05.jpg (62.45 KiB) Viewed 452 times

My first run battery box design has done great with the nominal chores of running a HT APRS system, charging phones, blowing up air mattresses and running LED lights in camp...

170429, Battery Box.jpg
8 AH, SLA battery with light. Has been great for remote station work and camp duties.
170429, Battery Box.jpg (63.35 KiB) Viewed 449 times

Managing power draw and injecting power back into the system whenever possible:

151217, Solar.jpg
Conserving power and injecting power...
151217, Solar.jpg (128.45 KiB) Viewed 437 times

160516, Blue Seas Terminal 02.JPG
Medium power box with minimal fused links.
160516, Blue Seas Terminal 02.JPG (105.09 KiB) Viewed 437 times

160516, Blue Seas Terminal 03.jpg
Plenty of protection and ports for powering in camp and at the communication site.
160516, Blue Seas Terminal 03.jpg (125.21 KiB) Viewed 437 times

200520, Power Distribution 640 01.jpg
A good example of my first run of solar for the 9 AH Bioenno system.
200520, Power Distribution 640 01.jpg (111.16 KiB) Viewed 430 times

200520, Power Distribution 640 02.jpg
This is the Renogy example of a multi-capable charge controller (lead acid, AGM and LI 14.2 volt charger rate specific).
200520, Power Distribution 640 02.jpg (95.49 KiB) Viewed 430 times
Last edited by lrsrngr on Thu Sep 10, 2020 9:14 pm, edited 20 times in total.
[b]HUA[/b] or "Hooah!" = Heard Understood & Acknowledged. In context: "Roger that sir, HUA!"

User avatar
OAUSA Board Member
Posts: 282
Joined: Thu Aug 29, 2013 9:07 pm
Call Sign: KK6DYO

Re: OAUSA Net - September 10, 2020 - Alternate Power in the Wilderness


Post by KK6DYO » Wed Sep 09, 2020 8:28 pm

Questions answered
What is a solar power system?
What can it realistically do?
How can I build one?

Content originally developed for 1/25/2018 net. I'm surprised to find nothing has much changed, even prices.

What is a solar power system?
SimpleSolarSystemx.jpg (49.63 KiB) Viewed 528 times

My reason for going solar
The addition of a refrigerator was a game changer for my outdoor experience. No longer had to rely on freeze-dried foods.
arb.jpg (57.63 KiB) Viewed 528 times

My imagination
I thought I might be able to run an air conditioner 24/7 for my trailer on hot desert days.
Climaterite5000BTUs.jpg (152.67 KiB) Viewed 528 times
Electrical Basics

Volts, Amps, Watts
powerVsEnergy.jpg (35.33 KiB) Viewed 528 times

Power over time is Energy
AmpsTimesVolts.jpg (11.32 KiB) Viewed 528 times

Formulas and Notations
  • Electrial pressure measured in Volts (V)
  • Electrical flow rate (current) measured in AmperesAmps (A)
  • Power measured in Watts (W) = Voltage * Current = V * A
  • Energy = power over time, measured in Watt-hours (Wh) = W * time period
  • Current over time measured in Amp-hours (Ah)
    • Typical measure of battery capacity with known voltage (e.g., 12V)

A fairly large (2' x 4') solar panel provides 100 Watts maximum, of course only while the sun is shining.

User avatar
OAUSA Board Member
Posts: 282
Joined: Thu Aug 29, 2013 9:07 pm
Call Sign: KK6DYO

Re: OAUSA Net - September 10, 2020 - Alternate Power in the Wilderness


Post by KK6DYO » Wed Sep 09, 2020 8:28 pm

How much power do you need?

Rechargeable battery Ni-MH AA
  • 1.2V x 2.4 Ah = 2.9 Wh
  • x how many?
Phone + Camera iPhone 8
  • 7 Wh
Rechargeable battery, HT Kenwood TH-K20 (5 Watts)
  • 7.4V x 1.8 Ah = 13.3 Wh
Rechargeable battery, flashlight 18650
  • 3.7V x 3.1 Ah = 11.5 Wh
Electric Vest
  • 7.4V x 2.6 Ah = 19 Wh
Tablet iPad Pro
  • 41 Wh
Refrigerator ARB 50 qt "maintain sub-freezing temperatures in 90°F heat"
  • 12V * 1.35A = 16.2W
  • x 24 hours = 389 Wh
Base station Kenwood TS-480SAT (100 Watts)
  • 13.8V x 20.5A = 283 W
  • x transmit how long?
Inverter - convert 12VDC to 120VAC
  • Watts x how long (e.g., 1000 Watts x 0.5 hr = 500 Wh
Heating / Air Conditioning ClimateRight CR5000ACH
  • Air Conditioner 5,000 BTUs/hr for 700 Watts (BTU = British Thermal Unit)
  • Heater 4,300 BTUs/hr for 1300 Watts (3 BTUs/hr = 1 Watt)
Heating Mr. Heater Portable Buddy (Propane)
  • 3,000 or 9,000 BTUs/hr propane -> 1,000 or 3,000 Watts eletrical
Cooking: Range
  • 7,000 BTUs/hr per burner -> 2,500 Watts

Meters that provide Watt-hours

Connects inline using Powerpoles. Other versions available.
WattMeter.png (253.85 KiB) Viewed 514 times

Connects inline with typical USB Type A and newer USB Type C connectors.
USBTester.png (223.25 KiB) Viewed 514 times

Calculate Your Energy Needs
  • Heating, cooling, cooking probably still not practical
  • Ask yourself: Do you really need that 1000-Watt inverter?
  • Monitor your electrical use (how far do you let your devices' batteries run down?)
  • Total your energy consumption in Watt-hours per day (natural solar cycle)
  • Allow for growth

User avatar
OAUSA Board Member
Posts: 282
Joined: Thu Aug 29, 2013 9:07 pm
Call Sign: KK6DYO

Re: OAUSA Net - September 10, 2020 - Alternate Power in the Wilderness


Post by KK6DYO » Wed Sep 09, 2020 8:30 pm

How much power can you get? The Panel
Panel Types
PanelMonovPoly.jpg (239.77 KiB) Viewed 527 times
  • Blackish
  • More efficient (15-20%)
  • Entire panel affected by any partial shading (newer panels built with bypass diodes)
  • Bluish, speckled
  • Less efficient (13-16%)
  • Supposedly affected less by partial shading
  • Possibly out of favor; not currently sold by Renogy
Comparison - Renogy 50-Watt
  • Monocrystalline: 24.8" x 21.3" (528 sq in), 9.9 lbs
  • Polycrystalline: 26.7" x 21.6'" (567 sq in, 9% larger), 11 lbs (11% heavier)
Rigid vs. Flexible vs. Folding 100-Watt
  • Rigid: 16.5 lbs $110 (less expensive)
  • Flexible: 4.4 lbs $190
  • Folding: 5.1 lbs $210 (easiest to store)
RigidPanel.png (196.7 KiB) Viewed 513 times
FlexiblePanel.png (196.7 KiB) Viewed 513 times
FoldingPanel.png (480.63 KiB) Viewed 513 times

Hold it!
Only ~100 Watts from one panel?
The panel just keeps the battery charged.
The battery collects power over time and stores it for later use.

  • Consider storage space and mounting needs (more later)
  • Easy to connect additional panels into system

User avatar
OAUSA Board Member
Posts: 282
Joined: Thu Aug 29, 2013 9:07 pm
Call Sign: KK6DYO

Re: OAUSA Net - September 10, 2020 - Alternate Power in the Wilderness


Post by KK6DYO » Wed Sep 09, 2020 8:34 pm

Heart of the system: The Battery

Battery Terms
  • Cold cranking amperage (CCA) = maximum current at 32°F for 30 seconds
  • Reserve capacity (RC) - minutes providing 25 Amps at 80°F while keeping voltage above 10.5V
  • State of charge (SOC) - percent of battery capacity remaining
  • Depth of discharge (DOD) - percent of battery capacity used = 100% - SOC
  • Deep cycle - ability to discharge deeply (50%+) before charging without harming battery
  • Capacity - energy stored in battery at rated voltage in Amp-hours (Ah)
  • C-Rating - fraction of charge/discharge rate relative to maximum capacity in one hour
Battery Chemistry
BatteryTypes.png (57.38 KiB) Viewed 527 times
More on lithium later

Type of Batteries by Purpose

  • Short, high-current bursts for cranking engine
  • Greater number of thinner lead plates
  • Higher CCA
  • Lower RC
  • DOD around 3%
  • Quickly recharge (topped off) by alternator
  • Will fail after a relatively lower number of deep cycles
Deep Cycle Battery
  • Continuous current for prolonged time
  • Smaller number of thicker lead plates
  • Lower CCA
  • 2 to 3x the RC
  • Recharge at lower amps for longer
  • DOD up to 50-80% hundreds of times
Marine Battery
  • In-between, but not a deep cycle battery
  • DOD around 20%
For a solar power system, we need a deep cycle battery

Type of Deep Cycle Batteries

Wet cell or flooded
  • Half the cost of Gel and AGM
  • Requires maintenance (water replacement, specific gravity testing)
  • Generally must be vented (hydrogen, possibly hydrogen sulfide)
  • Can spill sulfuric acid; must be kept from moving; may not be suitable for rough travel
  • Self discharge 13% of charge per month
  • Appropriate for household solar system, not mobile
Sealed Lead Acid: Absorbed Glass Mat (AGM)
  • Will not leak, even if punctured
  • Can be used in any orientation
  • Greater life span than wet cell
  • Self discharge 1 - 2% of charge per month
Sealed Lead Acid: Gel vs. AGM
  • Lose power faster in cold
  • Higher price
  • Shorter life span
  • Slower charging
  • Lower discharge rate
  • Self discharge 3% of charge per month
  • Better suited to deeper cycles
AGM it is!

Battery capacity falls off at low temperatures
Percent capacity vs degrees C (F)
BatteryPercentCapacityvTemperature.gif (12.97 KiB) Viewed 527 times
Battery Care
  • Keep battery charged, on a maintainer when not in use
  • Avoid discharging below 50% SOC
    ExpectedBatteryLifevDOD.gif (21.33 KiB) Viewed 527 times
  • Charge battery at correct voltage/amperage profile for type
  • Protect from extreme cold
    BatteryChargingVoltage.jpg (14.91 KiB) Viewed 527 times

AGM Charge Cycle Phase, Voltage, Amp
ChargeCycle.gif (10.46 KiB) Viewed 527 times

Battery Cost and Weight vs Capacity
BatteryWeightCost.gif (32.56 KiB) Viewed 527 times
State of Charge vs Voltage for AGM Battery
BatteryAGMStateOfCharge.jpg (23.37 KiB) Viewed 527 times
  • SLA AGM (or Lithium, next section)
  • Size based on your calculated daily energy needs
  • Multiplied by some number of days of bad weather based on destination
  • Multipled by factor based on expected temperature (see charts)
  • Get the largest battery you can physically manage to limit DOD and have surplus capacity
California’s Shift From Natural Gas to Solar Is Playing a Role in Rolling Blackouts

User avatar
OAUSA Board Member
Posts: 282
Joined: Thu Aug 29, 2013 9:07 pm
Call Sign: KK6DYO

Re: OAUSA Net - September 10, 2020 - Alternate Power in the Wilderness


Post by KK6DYO » Wed Sep 09, 2020 9:00 pm

The Future: Lithium Batteries
LithiumvAGM.jpg (215.39 KiB) Viewed 526 times
  • Cost 3x AGM
  • Requires special controller (but most current controllers handle lithium)
  • Shouldn't be charged under 0°C (lead acid to -22°C)
  • Half the weight of similar SLA
  • Can be nearly fully discharged without harm, not just 50%
  • Minimal self discharge
  • Possibly 10x the number of recharge cycles
  • Very high charging rate if power available
  • No minimum charge current
  • Maintains capacity in low temperatures
  • Runs well at high temperature
Lithium vs. SLA Performance in Cold
CapacityLithiumvAGM.gif (14.84 KiB) Viewed 526 times

Battery Comparison

Renogy LiFePO4 100 Ah
RenogyLiFePO4100AhBattery.jpg (37.54 KiB) Viewed 526 times
Vmaxtanks AGM 100 Ah
Vmaxtanks100AhBattery.jpg (60.59 KiB) Viewed 526 times
Renogy 100 Ah LiFePO4 vs. Vmaxtanks 100Ah SLA AGM
  • $900 vs. $275 (price has barely changed in 2½ years)
  • 28 lbs vs. 68 lbs
  • 90% DOD (1152 Wh) vs. 50% DOD (640 Wh)
  • 2000 cycles vs. 500 cycles (?)
  • Lifetime 2.3 MWh vs. 0.3 MWh (cycles x DOD Wh = megawatthours)
    • 7.7x life vs. 3.3x cost
Lithium is most cost effective battery, if you can justify the initial cost

Links to other LiFePO4 batteries
https://www.altestore.com/store/deep-cy ... es-p40844/
https://www.bioennopower.com/collection ... lf-12100as
https://www.ebay.com/sch/i.html?_nkw=li ... +12v+100ah

User avatar
OAUSA Board Member
Posts: 282
Joined: Thu Aug 29, 2013 9:07 pm
Call Sign: KK6DYO

Re: OAUSA Net - September 10, 2020 - Alternate Power in the Wilderness


Post by KK6DYO » Wed Sep 09, 2020 9:04 pm

The Brains of the System: The Controller

Also called Solar Charge Controller
  • Takes higher panel voltage (usually 18V)
  • Drives 12V load with limited current (usually not inverter)
  • Draws from battery when panel insufficient
  • Charges battery when panel surplus
  • Note: can also connect load (e.g., inverter) directly to battery
Controller.jpg (201.23 KiB) Viewed 526 times
Type of Controllers

Pulse Width Modulation (PWM)
  • Inexpensive
  • Functional
PWMController.png (110.8 KiB) Viewed 526 times
Controller Displays: Is it working?
StecaDisplayss.jpg (142.69 KiB) Viewed 526 times
Happy sight!
SOC100.jpg (168.57 KiB) Viewed 526 times
Maximum Power Point Tracking (MPPT)
  • Adjusts charging voltage to get maximum current into battery ("maximum power point")
  • Provide 10 to 30% more power to battery
  • Better yield when cloudy
  • Biggest advantage is with multiple panels wired in series for higher voltage
VictronSmartsolarMPPT.png (129.72 KiB) Viewed 495 times
Data Screen of BlueSolar iPhone App (Bluetooth)
MPPT107Watts.png (71.92 KiB) Viewed 526 times
  • Make sure load output provides sufficient current, if used; connect load directly to battery if not
  • Must have setting for your type of battery's recharging profile (older don't support lithium)
  • Should display State of Charge

User avatar
OAUSA Board Member
Posts: 282
Joined: Thu Aug 29, 2013 9:07 pm
Call Sign: KK6DYO

Re: OAUSA Net - September 10, 2020 - Alternate Power in the Wilderness


Post by KK6DYO » Wed Sep 09, 2020 9:10 pm

The Wiring, Connectors, and Fuses

Use recommended cable sizes or larger to avoid resistance / power loss
10 ga looks pretty good to handle two 100-Watt panels 25 feet away.
WireGaugevAmps.jpg (221.75 KiB) Viewed 526 times
Use color coded cable to avoid polarity problems
PowerwerxCable.jpg (87.57 KiB) Viewed 526 times
Good copper cable isn't cheap
Figure out how much you need. Might have panels in sun away from controller / battery in shade.
WireGaugePrice.png (31.07 KiB) Viewed 490 times

Most panels come with waterproof MC4 connectors
MC4ConnectorOnPanel.jpg (65.48 KiB) Viewed 526 times
MC4 Connector
MC4Connector.jpg (22.62 KiB) Viewed 526 times
MC4 Tool
MC4Tool.jpg (55.12 KiB) Viewed 526 times
Use convenient connectors, like Powerpoles
PowerpoleConnector.jpg (44.36 KiB) Viewed 526 times
A crimping tool is necessary for Powerpoles
Crimper.jpg (37.55 KiB) Viewed 526 times
MC4 Adapter to Powerpole
PowerpoleMC4Adapter.jpg (43.38 KiB) Viewed 526 times
Power Distribution Block to Connect Multiple Panels in Parallel
PowerDistributionBlock.png (309.63 KiB) Viewed 488 times
Be safe ... fuse everything
PowerpoleFuse.jpg (38.63 KiB) Viewed 526 times
DC Breakers
DCBreakers.png (155.54 KiB) Viewed 490 times

Inverter Cables
  • 1000 Watt 120VAC inverter
  • Divide by 12VDC for current / amperes -> 83 A
  • Check against length / current table
  • Get next larger gauge (smaller number) for safety
Inverter Cable
WeldingCablePrice.gif (25.52 KiB) Viewed 526 times
6 ft Inverter Cable, 2/0 Gauge, with Lugs
InverterCable.jpg (4.13 MiB) Viewed 526 times

Use proper fuses and ground your inverter
InverterFuses.jpg (250.44 KiB) Viewed 526 times
  • Powerpoles are quick and easy
  • Must protect from water and dust
  • Buy a good crimper if you're making your own cables

Protected Powerpole
PowerpoleProtected.jpg (181.82 KiB) Viewed 526 times

User avatar
OAUSA Board Member
Posts: 282
Joined: Thu Aug 29, 2013 9:07 pm
Call Sign: KK6DYO

Re: OAUSA Net - September 10, 2020 - Alternate Power in the Wilderness


Post by KK6DYO » Wed Sep 09, 2020 9:19 pm

How much energy can you really get? The Sun
SunOnPanel.jpg (12.92 KiB) Viewed 526 times
Designating Sun's Location: Azimuth and Elevation
SunAzEl.jpg (197.73 KiB) Viewed 526 times
Differences Between Summer and Winter Solstice
SunAzvEl.jpg (127.99 KiB) Viewed 526 times
Different Methods of Tracking
Trackingx.png (52.82 KiB) Viewed 526 times
Automatic Sun Tracking
SolarTracker.jpg (60.79 KiB) Viewed 526 times
Panel can be misaligned with sun by 20 degrees and still provide 95%
Cosine.png (11.58 KiB) Viewed 526 times
Modeling/Analysis Spreadsheet
  • Latitude
  • Day of year
  • Position of sun relative to panel direction throughout day (elevation: angle above horizon, azimuth: east to west position)
  • Atmospheric effect due to sun elevation (angle of sun in sky)
  • Various scenarios:
    • panel straight up
    • panel fixed pointing toward sun only at noon
    • panel position periodically changes with sun
    • panel fully tracks sun
Spreadsheet axes and color coding
  • Vertical axis is week of year, every two weeks
  • Horizontal axis is time of day, every half hour
  • Power harvest ranges from blue (less) - yellow - red (most)
PanelUp.png (102.15 KiB) Viewed 526 times
Modeling Spreadsheet
CarPanelOnRoof.jpg (141.45 KiB) Viewed 526 times
Panel Straight Up for Travel
IdahoSetup.jpg (287.95 KiB) Viewed 526 times
Keep the Pane in the Sunlight!
CarPanelForest.jpg (183.6 KiB) Viewed 526 times
Panel Flat on Roof
PanelUp.gif (76.84 KiB) Viewed 526 times
Panel Tracking Sun, Winter
PanelTrackWinter.gif (79.13 KiB) Viewed 526 times
Panel Tracking Sun, Summer
PanelTrackSummer.gif (75.01 KiB) Viewed 526 times
Graph Containing Key Information
Value multiplied by panel’s Watt rating gives maximum Watt-hours produced per day under perfect conditions
SolarHarvest.jpg (131.66 KiB) Viewed 526 times
  • Must understand seasonal path of sun, except during Summer
  • Panel mount should be able to easily tilt for sun's elevation and be moved for sun's azimuth
  • Periodically point panel where sun will on average be during next period
  • Figure out where shadows will be during each period and avoid them
  • Watch out for thin shadows (e.g., stalk of weed)
  • Two smaller (e.g., 50-watt) panels in series: easier to manage, can provide more power (higher voltage/less loss, MPPT controller)
    • But possible to lose production in any shade on either panel
  • You can mess with panels all day, or get better results by simply getting two panels, and pointing them roughly where the sun will be at noon that day, then forgetting about it!
100W Panel Stand with Three Tilt Angles
20170929 135000x.jpg
20170929 135000x.jpg (74.2 KiB) Viewed 526 times
50W Panel Stand with Three Tilt Angles
50WPanelStand.jpg (219.06 KiB) Viewed 526 times
Sun Az El Chart
SeasonalSunAzAlChart.png (92.83 KiB) Viewed 526 times
Panel Settings
AzElSetting.png (212.75 KiB) Viewed 526 times
100W Renogy Folding Suitcase Panel
RenogyFolding.gif (19.35 KiB) Viewed 526 times
Renogy100WattFoldingSuitcase-100s.jpg (44.32 KiB) Viewed 526 times

Post Reply


Who is online

Users browsing this forum: No registered users and 0 guests