Earn Monthly Dividends By Solar Powering Schools, Businesses and Communities

Join the Sun Exchange today and start generating and selling clean energy online through a global solar cell leasing platform. All from anywhere on the planet.

Sourcing our Solar Projects
Sun Exchange identifies schools, businesses and organisations that want to go solar. Our solar engineers work with local solar construction partners to carefully evaluate proposed solar projects and ensure they meet our core criteria:

* Economic and technical viability
* Social and environmental responsibility

Tip: Sign Up and get notified about new solar project crowd sales coming soon. 

View Upcoming Solar Projects Here

Buying Solar Cells
Once solar projects have been accepted as viable and responsible, we run a crowd sale for the solar cells that will power the project. Any individual or organisation, anywhere in the world, can sign up to be a Sun Exchange member and buy solar cells, even starting with a single solar cell.

Your solar cells will:

* Generate clean energy
* Make a positive social and environmental impact
* Earn income as you lease them to schools, businesses and other organisations
* Reduce your carbon footprint for years to come

  Tip: Buy solar cells in the local currency of the project using credit card, bank transfer, Sun Exchange  

   wallet or Bitcoin (BTC).

   View available solar projects

Installing Solar Cells
Once a solar cell crowd sale sells out (they go quickly!), installation of the solar project begins. The appointed local construction partners install your solar cells, which typically takes four to six weeks, but can be longer for larger projects.

Tip: Track the status of your solar cells through your Sun Exchange dashboard.

Effortless Solar Income
Generate and sell clean energy. Schools, businesses and organisations pay you to use the clean electricity your solar cells produce. Your lease starts when your solar cells start generating electricity.

You’ll receive your monthly solar income, net of insurance and servicing fees, into your Sun Exchange wallet in your choice of the local currency of the project or Bitcoin (BTC).

Your Sun Exchange dashboard keeps you up to date on:

* Solar project status updates
* Our solar cell earnings (BTC and ZAR)
* The clean energy your solar cells generate (kWh)
* The amount of carbon your solar cells offset (kg CO2)
* Your Sun Exchange wallet balance, payments and withdrawals

  Tip: The monthly income you accumulate in your Sun Exchange wallet can be used to buy more solar cells

   in other solar projects.

Start earning monetized sunshine and offset your carbon footprint, while powering schools, businesses and communities through Sun Exchange.

Join Our Global Solar Cell Community Here!

Is Solar Rising From the Ashes Again?

Recently, the Solar Energy sector has popped up on our watch-list of potential sectors to pay attention to. Over the past few weeks, the Solar Energy sector has been under some pricing pressure and has retraced nearly 50% of the previous trend across the sector. We, the research team at Technical Traders Ltd. understand the Trade War and uncertainty resulting from geopolitical tensions can sometimes create opportunities in the markets for all traders/investors. We just have to be smart enough to find them end execute them efficiently.

Is Solar Energy the next big trend to hit in the Energy sector? What is the potential for these stocks to move 10%, 20% or even 30%+ higher? Let’s take a look.

This first chart, a Weekly chart of First Solar (FSLR) presents us with an interesting price setup. After a dramatic price decline in May and June of 2018, the price decline abruptly halted near $52.00. In fact, this downside move ended almost as if prices “legged down” to the last known true support level. Historically, looking all the way back to the lows of 2012, this downside move represents just a little over a 38.2% retracement from the highs and coincides almost perfectly with a 50% retracement from the lows in 2017. These two numbers interest us because they show us that $53.50~55.00 is very likely a strong support level that is currently being tested.

Simple Fibonacci expansion analysis tells us any upside potential could target $61.35 (+12.65%), 69.95 (+28.44%) & 76.20 (+39.99%). These levels don’t take into consideration the potential for new breakout highs above $82.50. If this were to happen, we could see a +50% or more price upside happen.

Before we get too far ahead of ourselves, what would cause the Solar sector to begin a price advance at this stage in the economy? Renewed interest in the new technology of new infrastructure/government contracts? Replacing older technology with newer, higher performance, technology? Renewed interest from personal and corporate clients? What could cause this move?

You may remember that we’ve been suggesting that capital, cash, is always attempting to find solid sources of growth and opportunity while avoiding risk and depreciation. We’ve been suggesting that the spare cash on the planet has been rushing into the US stock markets by the boatload to take advantage of the strong dollar and the strong US stock market values. Could it be time for that capital to shift away from the FANGs and other leaders and move back into opportunistic equities that are somewhat off the radar?

Earnings for these companies for Q3 are set to be announced near October 28, 2018. With FSLR, the Q3 earnings have typically been fairly strong. One could attempt to assume Q3 2018 sales value may surprise the markets again and this could be a good time to consider the Solar Sector as an opportunity.

Our next chart is a Weekly ETF chart of INVESCO SOLAR (TAN). This chart presents a similar picture as the previous chart – a relatively strong pullback from April~June of 2018. The price pullback ends near a 50% Fibonacci retracement level and coincides quite nicely with our Tesla Vibrational Price Arc. We’ve drawn an arrow on the chart that suggests where we believe prices could be headed as long at this $21.75 support level holds.

Again, it does not take a genius to understand that any price advance from the $22.70 level to above $26.00 (or higher) would represent an almost +15% move. Any move above $28.00 from current levels would represent a +23.34% move. There is room for profits if our analysis is correct.

Lastly, we want to highlight what might be the most interesting setup in the Solar sector so far – Canadian Solar Inc (CSIQ). This Monthly chart attempt to show our readers exactly what has been transpiring in the Solar Sector for the past 5+ years. After peaking in early 2014, Solar technology lost its sparkle with investors. Slowly, over time, prices waned and dropped while attempting to find support. Technically, we view that support as the lows established in 2016 (prior to and near the US Presidential elections).

After that point it time, it is pretty clear to see that some renewed interest in the Solar Sector began to take place. Slowly, price advanced from the low as volume stayed somewhat muted. New rotational highs were established while the most recent low is still testing the 2016 lows. This tells us that the price trend, at least until we see a new breakdown low, is attempting to move higher.

CSIQ is currently trading near $14.75 and has upside potential above $21.00 on a breakout move. We are not saying this is definitely going to happen, but we do believe the Solar sector is setting up for an upside move and we do believe the potential for a new rotational high price to be established is quite strong. This means, finding the proper entry point and understanding the downside risk of these trades is critical.

Once CSIQ breaks our Red downward price sloping line, we would assume the price channel has been broken and we would expect the price to begin to rise dramatically.

As a member of our subscription services, you will be alerted to these, and other triggers, as our research team identifies them for the best chances at future success.

Please take a minute to visit The Technical Traders to learn how we can help you find new opportunities in the markets and stay ahead of these trends. Our most recent trade in UDOW returned 12.6% for our members last week. Please take a few minutes to understand how a small, dedicated, team of researchers with 53+ years of experience can make a difference in your future.

Get Our FREE Newsletter Right Here

Thomas Edison’s Dream Smashed

By Adam J. Crawford, Analyst

The incandescent light bulb was invented in the very early 1800s, but at that time was a device too crude and impractical for mass adoption. Over the next 80 years, at least 20 inventors contributed to its improvement, until, in 1880, Thomas Edison developed and patented a bulb that would last a miraculous 1,200 hours. Edison’s product was the first to offer the levels of functionality, durability, and affordability necessary for widespread commercial appeal. That’s why he gets credit for inventing the light bulb, even though he was decades late to the party.


Some 130 years after Edison’s patent was approved, the incandescent light bulb has basically the same features… a filament inside a glass bulb with a screw base. And for all those years, it’s been doing yeoman-like work providing clean, quality lighting (compared to the candles and oil lanterns of the 19^th century), in millions of homes and offices. Today, however, the incandescent light bulb is on its way out… and a multibillion-dollar industry will be forever changed.

Done In by Inefficiency

The incandescent bulb, though very effective, is notoriously inefficient. To understand why, one need only understand how it produces light. The filament (or wire) inside a bulb is heated by an electric current until it becomes so hot it glows.

The problem: only about 10% of the energy used by an incandescent bulb is converted into light; the rest is dissipated as usually unwanted heat.

This is a problem, not just for the homes and businesses using these bulbs, but also upstream at the power plants that produce the required energy. In an era when producers are wondering how they’re going to keep up with the surging demand amidst rising fuel costs and concern about the environmental impact of energy production is running high, such inefficiencies are frowned on.

Governments, of course, have the ability to put muscle behind their frowns… and they’re doing just that. In 2013, it became illegal in the United States to manufacture or import 75 and 100 watt incandescent bulbs. 40 and 60 watt bulbs were added to the ban in January of this year. The U.S. isn’t the only government actively limiting the use of incandescent bulbs. The European Union, Canada, Brazil, Australia, and even China are among many that have phase out programs aimed at forcing users to convert to an alternative technology.

For household applications, that primarily means a switch to those twisty shaped compact fluorescent lamps (CFLs), or the newest competition in town, light emitting diodes (LEDs).

A CFL’s spiral tube contains argon and mercury vapors, and they are far more efficient than the old Edison bulb. When an electrical current is passed through the vapors, invisible ultraviolet light is produced. The ultraviolet light is transformed into visible light when it strikes a fluorescent coating on the inside of the tube.. all at about one fourth the electrical cost for an equivalent amount of light from an incandescent lamp.

LEDs, in contrast, don’t use commonplace materials. Rather, they’re made from somewhat exotic semiconductor materials, like indium and gallium nitride. When an electrical current is passed through these semiconductors, energy is released in the form of particles called photons—the most basic units of light in physics, i.e., light’s equivalent of individual electrons. In the process, little is lost to heat and the materials take minimal wear, making for another very efficient light source, and one that lasts far longer than its competitors.

Comparing the Alternatives

Right now, LED bulbs are relatively expensive to produce. That’s because a bulb is not just a bulb when it comes to LEDs—it can’t be made brighter by just putting in a thicker filament or tube. Instead, each bulb is a complex web of up to dozens of small diodes, each roughly the size of a pinhead, wired together and to a ballast that regulates the electricity flowing through them.

When compared head to head with incandescent and CFL light bulbs, LEDs come out the clear winner in operating costs. But even with millions of these bulbs now shipping to Home Depot, they still fall down on initial cost:

60-WATT Equivalent	Incandescent	CFL	LED
Lumen	880	800	800
Life (hours)	1,000	8,000	25,000
Initial cost	$1.19	$5.00	$9.98
Yearly operating cost	$7.23	$1.81	$1.45

However, when you add up those advantages over that 25,000 hour lifetime, then the advantages start to become clear:

60-WATT Equivalent	Incandescent	CFL	LED
Yearly operating cost	$7.23	$1.81	$1.45
Years	23	23	23
23-year operating cost	$166.29	$41.63	$33.35
Initial cost	$1.19	$5.00	$10.00
Replacement cost	$28.56	$10.00	$0.00
Total cost	$196.04	$56.63	$43.35

As you can see, to produce roughly the same lumens (a measure of the amount of visible light emitted by a source), both CFLs and LEDs are hands-down more economical than incandescent bulbs.

Of course, in a residential scenario where a bulb is run for maybe three hours a day, it would take about 23 years to realize that big a savings. But put them in place in a commercial or industrial setting like the hundreds of lights running 24 hours a day in the local Walmart, and the savings add up quickly.

Still, why are we so bullish on the prospects for LEDs if they barely edge out their CFL competitors over tens of thousands of hours?

The first difference is environmental. CFLs have the inherent disadvantage of containing mercury, a toxic metal that poses health and environmental risks. Break one of these bulbs and you have a biohazard on your hands. There’s a real cost to recycling these bulbs and containing the mess from those that are just tossed in the trash heap. It’s a cost that will certainly be shifted back to consumers of the bulbs if environmental legislation continues on its same path.

Further still, over its life, an LED bulb is already 25% more economical than a CFL. When compared to an incandescent bulb, either is a huge cost winner. But when it comes down to dollars and cents, the LED wins today. The only reason not go that route is the big upfront cost difference, which when buying tens of thousands of bulbs at a time (as many commercial companies do) can be a hard pill to swallow.

However, the cost of LEDs has been falling fast in recent years and will continue to do so. In 2011, a 60 watt equivalent LED bulb retailed for about $40. In 2012, the price fell below $20. Today, it’s less than $10.

As volumes increase and competition among manufacturers and retailers intensifies, prices will continue to fall. Some industry analysts see a $5 LED on the near horizon. We wouldn’t bet against it.

The price could go even lower if manufacturers can successfully implement a cost-reduction break through. Specifically, LED devices are built on expensive aluminum oxide substrates. But manufacturers are working on ways to build on substrates made of silicon, which would substantially reduce defects and thus costs. As prices drop, and if environmental law hits mercury laced CFLs next, LED’s cost advantage will start to widen significantly.

Inflection Point

This all means that the LED’s time has arrived. According to IHS, a global market and economic research firm, unit shipments of LED lighting devices will grow at a compounded annual rate of 40% between now and 2020.

In 2011, the size of the global lighting market was about $96 billion, and LED devices accounted for about 12% of that amount. By 2020, McKinsey & Company projects, the size of the market will be $136 billion, of which 63% will be attributable to LEDs.

With the LED bulb, we have a trend that’s been in the making for several years… and it’s now ready to surge. How should an investor play it? Certainly not with a blindfold and a dartboard, or a whole sector buy like an ETF, because not all participants in this market will prosper.

Some will not be a pure enough play to benefit, or will be cannibalizing their own incandescent and CFL business… like GE and Phillips. Others will find themselves producing a commodity with ever thinning margins… like Cree. And others still already have much of the anticipated growth priced into their shares.
However, we scanned the field and found a company that is well positioned to benefit from the growth of the LED market while, at the same time, actually improving its margins.

We believe this company’s stock is undervalued. That’s why we’re recommending it in the next issue of BIG TECH

For access to this recommendation and many more, simply sign up for a risk free trial of BIG TECH. 

If you decide to keep your subscription, it will only cost a mere $99, nothing compared to the profits just this one investment should bring. But, if for any reason you’re unsatisfied, simply cancel to receive a prompt, courteous, and complete refund of the entire subscription price. You have 3 full months to make up your mind.

The article Thomas Edison’s Dream Smashed was originally published at Casey Research

Do you need blocking diodes when adding a wind turbine to your DIY solar system?

One of forum members, Ladyhawk, brought up a great discussion this week. And as always one members jumped right in and gave a priceless response. Where are you finding this anywhere else on the internet?

Ladyhawk ask....

If I add a wind turbine to my system, do I need to put blocking diodes on each one of my Harbor Freight solar panels? I had planned to hook my turbine up direct to a 12 volt element but have been told that it a bad idea due to stalling turbine, overheating wires, etc.

Member Hillbilly Gene responds....

Yes, you need at least two diodes if you add a Wind Turbine to your system.

A diode will “block” voltage if the voltage is more positive on the diode’s cathode side (bar side) than on its anode side (arrowhead side).

If the sun is out, and no wind blowing, you want the wind turbine diode to stop solar panel voltage from pushing current into the wind turbine.

If the wind is blowing at night you want the solar panel diodes to stop wind turbine voltage from pushing current into the solar panels.

The internal diode in the Harbor Freight charge controller stops battery voltage pushing current back into the solar panels if those panels have no diodes added, which is the way the Harbor Freight kit comes out of the box.

The solar panels can be shorted together at their outputs and two panel diodes removed to get to a two diode system, but doing so will then not stop the solar panels from pushing current into each other if one or more of the panels are shaded.  This Harbor Freight solar panel backfeeding was discussed here.

I would recommend using the four diodes, but for the best results I recommend a separate charge controller for the wind turbine.

Come and join us on the DIY Solar Energy Forum and ask that tough DIY solar system question. We have qualified members who are willing to help!


Everything You Need to Produce Your Own Solar Energy.....Check Out New World Solar Power!

-->

Off Grid 100% Solar Powered Retail Store " The Laurel Mountain Shop"

George took an old country store,and upgraded inside and out. And he runs off 100% solar power.



Everything You Need to Produce Your Own Solar Energy.....Check Out New World Solar Power!

Carl's Solar Powered Automatic Gate Opener

Probably the two most common reasons for people getting started in making their own solar energy is getting that quote from an electrician to run power to the new shed or out building on the back of the property or getting power out to the new electric automatic driveway gate opener.

Today's video comes from our forum member Carl Masters as he walks us through his set up using the Mighty Mule MM600ETPRO automatic gate opener and the Harbor Freight 45 watt solar kit.

Carl's original post......

I bought a 45 Watt Harbor Freight kit a little over two years ago to see if it would power a gate opener. It is very overkill for the application and I am extremely happy with it so I thought I would post.

My gate is a 2" square steel framed solid 6' cedar privacy fence panel that is 14 feet long on Bulldog hinges (like chain link gate hinges - no bearings). It hangs on a 6" steel tube post in concrete. The opener is a Mighty Mule MM600ETPRO setup that is cycled 6 to 8 times a day. The opener is way under powered for the weight of the gate and sometimes needs human help on windy days.

The Harbor Freight solar kit keeps the single RV battery charged to upper 12's to upper 13 volts at all times. The opener doesn't even seem to affect it. I occasionally hook my RV's batteries to the system to keep them topped up too. I am very happy with the kit. It has been trouble free even during light hail using the supplied controller. I literally haven't had to do a thing to it.

I have another one of the old aluminum framed kits (still in the box) in the garage. I am thinking about setting it up on to of a carport my tractor and mowers live in to keep batteries charged and power LED cameras and IR spotlights for our security system.


Everything You Need to Produce Your Own Solar Energy.....Check Out New World Solar Power!

-->

What's going on at the DIY Solar Energy Community Forum

It's cold and miserable outside in much of the country, but that's not keeping the members at the DIY Solar Energy Forum from getting ready for spring time. So what are our 1,100 active members talking about?

Harbor Freight Charge Controller as a PDU? 

Ladyhawk is having trouble with her Harbor Freight charge controller. Can you help?

12 Volt Deep Cycle Batteries, Best Price/ Place to Buy? 

Finding a battery is no problem when you have a Walmart, Costco or Sams Club near by. Where do you find a good deep cycle battery?

Solar hot air window heater

No, we don't just talk about solar systems. Featured member Bill K. is always coming up with something new and this week it's solar window heaters. This looks easy and affordable.

Xantrex C35 Diversion Question 

We are surprised this isn't more popular, the Xantrex C series controllers have a feature that diverts the incoming charge to a 12 volt element in a water heater, or anywhere else you want to send it, when your batteries reach full charge. Do you know how to wire this?

Visit the forum and put our search bar to work, chances are you'll find the answer you are looking for at The DIY Solar Energy forum


Everything You Need to Produce Your Own Solar Energy.....Check Out New World Solar Power!

Proper Battery Wiring Technique

There is nothing more important when it comes to building your DIY solar system then cable and wire sizing. One of our featured members on the DIY Solar Energy Forum, Dale Marshall, has written an article/discussion that highlights the most important aspect of successfully connecting multiple batteries. Please feel free to join the conversation with your input or questions...... 

I have noticed lately that many people are having problems with low power issues, Improper battery charging or certain batteries in your bank of batteries failing. I have dealt with these issues and have done some experiments and also lots of Searching down best methods of charging and power draw issue.

I have Found only 1 solution that works correctly since. It also makes for even battery charging and equal power draw across the battery bank.

I have 2 Diagrams I want to share with you here .

The only rule you have to follow is this....Use proper gauge wire and all wires going to the Positive and Negative Combiners Must be of " EQUAL LENGTHS" Including any wires tying 2 batteries in series You know those 6-8 inch jumper cables must be 6 or 8 inch.

It is of my opinion and researching. This is the only true way to make you batteries have a long and reared life span. And you can enjoy for years to come.

Everything You Need to Produce Your Own Solar Energy.....Check Out New World Solar Power! -->

Adjusting Your Voltage Reading on the Harbor Freight Charge Controller

We hear a lot of complaints from DIY Solar Enthusiast about incorrect readings on their Harbor Freight charge controllers.....better known on our forum as the PDU. The "Power Distribution Unit".

But complain no more, forum Bill K. shows us [see photo] how you can take the cover off that unit and where you can adjust the cal pot.

Joins us on the forum and put our search bar in the upper right corner to work for answers to most of your problems with your DIY solar system.

See you on the forum!










Everything You Need to Produce Your Own Solar Energy.....Check Out New World Solar Power!

-->

They're Back....145 Watt Solar Panels for Only $160 each includes FREE Shipping

Now is the time, no more excuses. If you have been thinking about getting started making your own solar energy now is the time. We will be blowing out our wildly popular 145 watt solar panels for only $160 dollars each. And that includes free shipping.

It's a little bit different deal this time, they are only available in pairs and will include MC4 "Y" cables. Total for two panels with Y cables is $328.00 to your door.


Features include industry leading power tolerances of +3/-0%. 3 year warranty on workmanship, 90% after 15 years power warranty. ISO 9001:2000 certified.


Panel dimensions are  58.27"  x  26.58"  x  1.38" and weighs 26.4 pounds.

DM Solar modules offer industry leading performance and proprietary design. They boast of a high conversion efficiency, heavy duty anodized frames, high impact tempered glass and weather resistant junction boxes for easy, safe field interconnection and promising years of reliable service.




Use this link for your purchase right now!


So don't miss out, you will be making your own solar energy next week!


Everything You Need to Produce Your Own Solar Energy.....Check Out New World Solar Power!

Must see....Big Moe's Lectric Leopard

Is this the future of the average solar family 10, 20 maybe 30 years from now? Most of you are familiar with Big Moe, one of our forum members over at The DIY Solar Energy Forum. He is best known as the man with the worlds largest collection of Harbor Freight solar panels which now also features the wildly popular DM Solar 145 watt solar panels. You can usually catch a glimpse of his set up as it is more often then not the banner photo across the top of the page at the forum.

Well now Big Moe [the Michael Jordan of the DIY solar community] has taken it to the next level. Buy purchasing a "Lectric Leopord" electric car. These cars were manufactured by the U.S. Electricar Company in Massachusetts on the rolling chassis of a Renault LeCar.

Not only will Big Moe be charging the battery bank in the Lectric Leopard with his massive solar set up but the cars battery bank becomes a alternate battery bank for the whole house in a pinch.

Please feel free to come over to the forum and join the discussion and follow the changes that are coming as Big Moe has already planned a voltage change....

From Moe's post....They orignally were 48v with 16 - 6v batteries. This one has been converted over to a modern controller board and is now 72v with 12 - 6v batteries. I will be switching them to 9 - 8v batteries soon and will used these 16 Trojan T-105's for a second battery bank on my solar array.

Just click here to join the discussion!


 Everything You Need to Produce Your Own Solar Energy.....Check Out New World Solar Power!

Keeping Food & Beverages Cold with Solar Power

Is a small DIY solar system enough to keep a refrigerator going? Well, it looks like it depends on what frig you pick.

New video from John J......Keeping food fresh & beverages cold in camp with solar power.





Everything You Need to Produce Your Own Solar Energy.....Check Out New World Solar Power!

The new electric bill is in.....and it don't look good for "Mr. Big Grid"

Sick of hearing "it takes $20,000 to do any solar on your home?" And what does a $20,000 grid tie system get you if the power goes out? Darkness. When the likes of Solar City or your local solar installer is selling you on a system that should be your first question....what happens when storms knock out our grid power. And while a small do it yourself system is no replacement for your commercial power it will keep your family from being plunged into darkness.

So if you did take up creating your own solar energy as a hobby or a project, could you afford it? Can you save money in the process? Well, check out our forum member Bill K.s recent electric bill [posted below], he is kind enough to post it monthly. Bill has a simple DIY solar system and recently added a small solar water heating unit. Here is the conversation.

Check out his bill and you be the judge. Then come over and become part of the friendliest most helpful Do it yourself solar energy community. But be forewarned don't click here if you don't need another hobby or addiction.






Everything You Need to Produce Your Own Solar Energy.....Check Out New World Solar Power!

Will Harbor Freight Solar Panels Back Feed Each Other?

From guest blogger Hillbilly Gene......

The Inquiry: Will HF Solar Panels Back Feed Each Other?

No one, to my knowledge, has ever conducted a test to see if three solar arrays, such as included in the Harbor Freight 45 Watt kit, will interact and back feed current from one panel to another. I know that the HF charge controller has “blocking” diodes to prevent a nominal 12 volts from the battery from potentially feeding current back to the solar panels at night.

Logic would suggest that if back feeding were not possible, then HF would not have included those diodes. If back fed current were possible with a nominal 12 volts, then why wouldn’t the 23.5 Voc of one panel back feed another panel being shaded, and not producing 23.5 Voc?

Are those blocking diodes in the HF CC there for another reason? Such as if someone inadvertently shorts the solar panel input wiring? Instant smoke and fire inside the HF CC would result without those diodes; not counting melted wire back to the location of the “short”. I know this scenario would only happen if the negative of the battery was also connected to the negative of the panels, but anything is possible. Anyone concerned with grounding issues might do this; such as grounding the negative of the solar panels and also grounding the negative of the battery at the same point. That wiring would set up that Murphy’s law scenario.
I decided to conduct a test to see for myself.

Test Instrumentation:

My instrumentation was fairly simple:

Two HF 98025 Multimeters:

One was used with the 10ADC function; the other was used as a regular voltmeter.

One Harbor Freight 45-Watt Solar Panel Kit. This kit has been installed and working beyond the six-month “seasoning” period; the time when the electrical output of the 3 panels are expected to be permanently reduced by 20% from their like-new output. This HF kit is assembled per the HF manual, pointed at the sun with no particular fussing as to exact angle.

Brown corrugated cardboard: large enough to cover just one HF panel.

Miscellaneous. This is a category for anything used, but not specifically mentioned, such as jumper wires with alligator clips. Muttering and cussing belongs here.

Testing Parameters:
First, all three panels were cleaned with “Windex”

Testing consisted of reading the combined voltage of all the parallel panels and reading the amps of one panel being shaded or not shaded.

Shading was a piece of corrugated cardboard that just fit over one panel. It was placed on top of that panel, with no provision to secure it. Light may have filtered into the panel around the cardboard edge, but I made sure that no sunlight was directly on the panel. The one-panel shading is labeled “drastic” shading because I doubt any panel would receive that much individual shade in any normal installation.

Volts and amps were recorded with the cardboard on or off the panel, and with the rocker switch of the HF CC on or off. Rocker switch “on” was the battery-charging voltage; Rocker switch “off” simulated Voc, or no charging.

This test was conducted on the 17 of December. That’s close enough to the winter solstice (21 December) to be at a time when incoming solar power is weakest, because the earth’s axis is tilted as far north as it will get annually. A Photon spit out by the sun takes 8.3 minutes to reach earth and slows down when it reaches the earth’s atmosphere. Since the earth is tilted away from the sun during the winter it has effectively more atmosphere to travel through, and loses energy.

The sun’s Photons just don’t have enough energy to knock too many electrons silly in the panel this time of year, but the dazed electrons that do get whacked make up the current flow from the panels to the charge controller.

Time was about 9:30 – 10:30 am. Latitude in northern hemisphere: draw a line between Kansas City and Indianapolis, and you’re close enough. I believe anywhere mid-country between Louisiana and the Canadian border would give approximately the same results. It was a clear, sunny, day. Ambient temperature was 32°F.
The circuit wiring used is shown in Fig. 1

Test Number 1:
With a HF 98025 Multimeter on the 10A scale (reading panel #1 amps), and a second HF 98025 Multimeter set to 200 VDC (reading the parallel 3-panel-array voltage at the charge controller).

Here is the Test #1 data I collected:


The yellow-highlighted results of Test 1-D indicated that the shaded panel #1 wasbeing back fed current from the other panels. Minus amps means the current is going in the opposite direction from Test 1-B. The Volts of all the panels also apparently dropped about 0.2 volts.

Reasons for Test Number 2:
I wanted to see exactly what that –0.02 amp reading (-20ma) in Test 1-D really was. The HF 98025 meter will read up to 9.99 amps on the normal 10-Amp scale with a precision of ± two rightmost digits, meaning that –0.02 reading could be –0.12 or it could be –0.00.
 
So I devised another test to determine that amps value given in Test 1-D more precisely.

Test Number Two:

Start of theory:
First, the theory guiding this test: I know that E = I x R. So if I make R = 1 ohm, then E = I x one. Any voltage that is read across a one-ohm resistor can be interpreted as current, because the formula now reduces to E = I. It’ll be a cheap Hillbilly Ammeter Substitute.

A 1-watt resistor was chosen because W = I (squared) x R. Since Panel #1 has a rating of 1-amp, my equation now becomes W = (1-amp) x (1-amp) x (1-ohm) = 1 Watt, which will easily handle solar panel #1 current.

And then I assembled the circuit as shown in Fig. 2.

 
Using the HF #1 Voltmeter setting as an Ammeter setting:

The HF #1 Multimeter was set to either the 200m DCV or the 2000m DCV range as needed. Normally the 200m range displays up to 0.20 volts, and the 2000m range displays up to 2.00 volts. Because of my setup, I can now read and instantly interpret the meter either as a 200-milliamp (0.200 amp) range or as a 2000-milliamp range (2.000 amp, actually 1.999 amp) respectively (m = 1/1000), rather than voltage. The HF meter on these ranges has an accuracy of ± one rightmost digit, which is much better than the 10A DC range accuracy of ± tworightmost digits.

The polarity of the HF #1 meter was selected to read positive current from the panel to the charge controller. Any resistance in a working circuit will have a voltage drop, and that voltage drop will have a polarity to oppose the source voltage. The source voltage in this case is the voltage from solar panel #1. If the voltage across that resistor switches polarity it means current is going intothe solar panel.

End of sermon theory.

The testing parameters duplicated Test Number 1 parameters.
Test Number 1 is repeated here for easy reading and comparing with Test Number 2

Results of Test 2:
 
Comparisons of both tests:

Focusing on the yellow highlighted numbers:
Test 1-D indicated panel back feeding of -20ma intopanel #1 by panels 2 and 3, but the exact amount was either inconclusive or suspect. CC not charging, panel #1 drastically shaded, Voc = 23.1
“OL” in Test 2-B stands for overload, or more than that meter setting of 200mv could read
Test 2-C indicated back feeding of –2.2ma intopanel #1. CC charging, panel #1 drastically shaded. Note that Test 1-C under the same conditions did not indicate any back feeding, because the 10-A ammeter setting in 1-C can’t read 0.002 amps, although the polarity was –000.
Test 2-D confirms Test 1-D that back feeding isoccurring and the amount is –21.4ma.
That cheap Hillbilly Ammeter Substitute mentioned in the Test Number Two Theorysection worked as planned by verifying panel #1 back feeding of over –20ma. See test 1-D vs. test 2-D.

Conclusion:
My conclusion is: The HF Solar Panels WILL back feed, given the right conditions. Murphy’s law rules here, and diodes are cheap. I will therefore wire my permanent kit in the following manner:

If I have to use a combiner box I will install the diodes and fuses in that box. If I don’t need a combiner box I will place the diodes and fuses somewhere convenient near the charge controller.

I want to redo this testing about June 21, when the solar energy is at it’s maximum. My thoughts are that there will be more amps back feeding because there will be more current available from the uncovered panels at that time of year. The sun’s Photons has more muscle.

As usual, I will be grateful for anyone pointing out any trashing of theory or for any sins of omission. I try to include everything, even if it means being long winded.

Hillbilly Gene

P.S. For those that don’t know, Murphy’s lawstates: “If anything can go wrong, it will”.
Some will say Murphy was an optimist.

Please join us over on the Do it yourself solar energy forum and check out all of Hillbilly Genes articles.

Everything You Need to Produce Your Own Solar Energy.....Check Out New World Solar Power!