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[Articles Home]  [Add Article]  

A Solar Powered Ham Radio Station

from Rob Norman, VK5SW on June 18, 2019
View comments about this article!

"Editor's Note: Due to the popularity of some of eHam's older articles, many of which you may not have read, the eHam.net team has decided to rerun some of the best articles that we have received since eHam's inception. These articles will be reprinted to add to the quality of eHam's content and in a show of appreciation to the authors of these articles." This article was originally published on: 02/06/2009





A Solar Powered Ham Radio Station

Since I wrote the article called ' Modest 20 foot Tower ', I've had enquiries, wanting to know more about my 'Solar Powered Station in the Bush'...

There's an interest, nowadays, in alternative forms of power but the most popular for Amateur Radio Operators would have to be Solar Power... The problem, however, is that I don't know much about it but I can share with you what I do know... I've been operating my ' Solar Station in the Bush ' for a couple of years now and it's been working very well, although my situation is probably a little different to most, in that, we use our property as a ' getaway ' and we're only there for a few days each month or so, and therefore the demand on the battery is infrequent...

There are basically 3 components to a Solar Installation... The Battery, the Solar Panel and the Controller to regulate the current going into the battery... It's basically as simple as that...

The sizes of these, depend on the amount of current you need to draw from the battery and the duration... Once you work out these 2 requirements, you're able to figure out the capacities of the 3 components... In my case, for example, I operate CW on HF, so the current draw on the battery would be about 20 Amps or so, although I only run the radios at about 75% of full power, ie 75 watts... So, let's say the current demand is about 20 Amps anyway... If I was to run the transmitter for 1 hour, it would mean that the battery has used 20 Amp Hours in that one hour period... Batteries are rated in terms of their voltage and the number of Amp Hours that they can supply... However, batteries used with solar panels need to be of the ' Deep Cycle ' type... They should only be discharged up to and no more than about 20% of their capacity... If, for example, you have a 100 Amp Hour battery, it shouldn't be discharged by more than 20%. ie 20 Amp Hours so that 80 Amp Hours of the battery's capacity should still be available...

The battery I use has an Amp Hour rating of 670 Amp Hours... 20% of that is approximately 130 Amp Hours... So, I'm able to draw that amount, 130 Amp Hours without harm to the battery... Most people would think this to be ' Overkill ' but I tend to do this sort of thing... Therefore, if the transmitter was to run for 6 and a half hours, at 20 Amps, the battery would be down to the allowable ' discharge level '... There are many different types of batteries available nowadays, but I bought a lead acid type, made by Exide in the USA, because it's a proven and reliable type of battery, old technology... It consists of 2 volt cells in series to form 6 volt batteries, 2 of which make up the 12 volt supply... A battery this size can power a small house but you would need a number of panels to recharge the battery due to the regular current drain by house hold appliances etc... They're not cheap... This one cost $1500, Australian, a couple of years ago and the expected life is about 10 years if looked after properly... The voltage at the battery fluctuates with the current coming into it from the panel... It may swing from 12 volts or so of a night to 14.5 volts or so in the daytime... I have 3 different radios that I have used with this battery and the voltage swing doesn't seem to affect them...

The amount of charge going into the battery is dependent on the size of the panel, it's direction towards the Sun and the availability of Sunshine... Since we're not at the Radio QTH all the time and drawing current, the battery doesn't need to be charged quickly on a regular basis... One 80 watt panel is sufficient for my needs ie. to keep it charged... It's made by BP and cost nearly $700 Aust... The direction that the panel faces is important to maximise the exposure to the Sun... Also, the angle to the horizon should be optimized to ensure that the Sun hits the panel as near as perpendicular as possible throughout the year... High tech ones track the sun...

The ' Charge Controller, ' or ' Regulator ' ensures that the right amount of current from the panel is fed to the battery... When there is a large current drain from the battery, the regulator will allow maximum current to flow into the battery from the solar panel... With the panel shown, a maximum current of nearly 5 Amps can be produced with a cloudless sky... When the battery is nearly fully charged, only a small amount of current is sent to it... The maximum Amp Hours this panel can manage at this QTH seems to be about 35 AH or so a day ... When buying the battery and panel, the sales people will sell you the appropriate controller as well... The charge controller is able to tell you a lot of information... eg. the voltage at the battery terminals at present, the amount of current going into the battery at the moment, the number of Amp Hours already gone into the battery so far today, the total Amp Hours sent to the battery each day etc...

The other consideration is the wires connecting components... To reduce voltage drop, ensure that you use heavy gauge wires and also use fuses in the main lines... Ask the sales people questions, they want your business...

I hope this is of help in building your own Solar Powered Station... You can see mine, here, at www.VK5SW.com

73's for now... Rob - VK5SW...

Member Comments:
This article has expired. No more comments may be added.
 
A Solar Powered Ham Radio Station  
by ONAIR on June 18, 2019 Mail this to a friend!
Nice set up! I think solar is becoming more popular with the QRP crowd since they can be very useful out in the boonies and prices have dropped!
 
A Solar Powered Ham Radio Station  
by AE5X on June 18, 2019 Mail this to a friend!
My shack has been solar powered for almost 3 years now. The only items not are the KPA-500 and the rotator.

With most equipment operating from 12VDC (13.8), ham stations make ideal test platforms for those wanting to experiment with solar power without the need for inverters. I use two 100-watt Renogy panels on the roof, feeding two 6V Trojan T105 batteries in series via an MPPT controller.

http://ae5x.blogspot.com/2016/08/operating-on-solar-power.html
 
RE: A Solar Powered Ham Radio Station  
by KB1GMX on June 18, 2019 Mail this to a friend!
Been running on solar power for over 12 years and
the current set of batteries for nearly 7 years.

Several items since the article is somewhat old:

Solar panels are now (even with tariffs) under 1$ US
per watt for panels over 50W. THe price of solar has dropped greatly.

Charge controllers and inverters are also greatly cheaper and many vendors.

Large batteries are not cheaper but they haven't increased much either. Lead acid is still the
cheapest but there are many technologies some
more earth friendly if that's important.

He is right going big and keeping discharge shallow
is still a good thing and extends battery life. However new with lower cost solar enough power to insure a full charge during a contest weekend of
less than one day in the winter is advised.

My most recent set of batteries are NiCd the large 150AH flooded industrial type, they were rescues
from a Fire department radio system upgrade. They
are now about 10 years old and showing no stress. Well treated life span for those is 20 years plus. Nominal voltage is 1.25 per cell for the 10 of them and top off charge is 14.8V. Solar power keeps them
topped, nearly 400W of it and a sufficiently large charge controller to handle the amps. The radios
all use power from that and a well fused distribution
and monitoring panel exists for both safety and
system checks.

For those that note the NiCd cells are not the most efficient battery technology I point out... NiCd
are durable and tolerate deep discharge and outright abuse well compared to other types. With 10 cells
the DC voltage keeps many of the power fussy radios
happy as the DC bus voltage rarely drops below 12V
and 11V is around 60-70% depth of discharge. That
and the price (free) was a factor!

The other side is with 400W a sunny day in winter
can supply nearly 22A Which the large NiCd can
absorb without issue (C/10 rate is 15A). Typical winter day can easily put back 40-70AH (1100-1600WH).
the worst days here are in Feburary where I may see 500WH of charge due to little if any sun. The big battery helps here. During the summer I have enough
to allow the charge controller to divert and take other loads. Of the four panels there are two used ones and two smaller new ones so the cost for the solar is about 250$ and charge controller was a built up by me so its cost if purchased is around 120$. The rest is wire and fuses and a lot of PowerPole for interconnect.

The upside is station power and LED lighting run
off the solar/battery with plenty of reserve. Even with a foot of snow the panels put out enough to
charge as needed. That is where excess solar helps.
It is handy to be able to ride through power failures
without notice on the air and also provide emergency lighting to the remaining house as well.

Solar power can easily run a 100W station and the
cost due to declining cost of solar panels and controllers can be quite moderate.


Allison
 
A Solar Powered Ham Radio Station  
by KK6BXO on June 19, 2019 Mail this to a friend!
Good article and good follow up comments.

Nobody has mentioned circuit protection. Remember that a big battery can deliver arc-welding level current to a short circuit! Some of the marine electrical system companies like Blue Sea Systems make good quality fuse and circuit breaker products for DC circuits. They are reasonably priced and available through West Marine, Amazon, etc.

https://www.bluesea.com/products/category/16/Fuse_Blocks
 
RE: A Solar Powered Ham Radio Station  
by KC6RWI on June 19, 2019 Mail this to a friend!
I was going to say use a couple of car batteries, but then I realized I was confusing cold cranking amps with amp hrs.
 
RE: A Solar Powered Ham Radio Station  
by KB1GMX on June 19, 2019 Mail this to a friend!
Fusing and circuit breakers are a big part of my installation. Also adequate sized wire so that
fuses blow before wire heating happens.

One thing I did is the load side is well protected then I decided to add a few large fuses (100A) between cells
in case of a short.

Yes, the big batteries can arc weld! I've cabled them for that when I first got them for a emergency repair.
100-200A is nothing for those big cells.

Another thing to be wary of is Hydrogen from charging
or high loads. Ventilate to outdoors.

Allison
 
A Solar Powered Ham Radio Station  
by K7EXJ on June 20, 2019 Mail this to a friend!
My XYL and I cruised our 32' sailboat (Kibitka) for five years. When we left our home port of Everett, WA in 1980 we had one child (a girl, 2-1/2). When we came back, in 1985, we had two kids (the addition was a boy born in Guaymas, MX in 1983).

When we were in San Francisco I bought two, 33-Watt, solar panels. I never "installed" them but kept them loose so I could move them around. The "charge controller" was me and my new digital voltmeter. The panels fed into two deep-cycle 12vdc batteries via a large germanium diode (much lower voltage loss... but almost impossible to find now). When battery voltage was under 12.5vdc I set out the panels and aimed them at the sun. When voltage got to 14.5vdc I disconnected the panels and stored them away.

This gave us enough power for a 100-watt Icom IC702 transceiver (modified to also cover marine SSB), interior lights, and 12vdc refrigeration! (Enough ice for one sundowner for the XYL and me each evening.)

Later I built a wind generator out of a 36vdc motor, and several pieces of 1/2" steel plumbing. I carved a propeller sitting on a beach near La Paz, Baja, connected it all together, ran it through that germanium diode, and hung the contraption up in the foretriangle above our cabin using a halyard.

After that we could sometimes have two sundowners apiece.

The solar panels were quiet but UV caused the epoxy the mfgr used to encapsulate the cells to fog to the point of uselessness. (They were guaranteed for life but the seller demurred, saying that I had left them in the sun too much...) The wind generator worked wonderfully but if the wind got above 15kts it made a terrible noise so I had to get out on deck many nights in my skivvies to tie the tail of the device to a shroud to shut it down in order to get some sleep.

In the 1980s the question asked the most about solar was, "Do those things work?" We were the only cruising sailboat with them aboard that we saw back then and I'm not sure everyone believed me when I said that, yes, they did work.

Of course, many people were naive about a lot back then. We had a stainless steel drip-diesel heater in the cabin and the question most asked about that was, "Is that a capuccino machine?"
 
RE: A Solar Powered Ham Radio Station  
by N8FVJ on June 21, 2019 Mail this to a friend!
If I had the set up as shown, I would vent the smelly battery out gassing to the outside of the building. An alternate battery would be lithium, but I heard of fires if the lithium battery is shorted. So, be careful using lithium batteries.
 
A Solar Powered Ham Radio Station  
by W0WCA on June 25, 2019 Mail this to a friend!
Me thinks that the needed soar power for ham communication is in the form of sun spaughts of which there are few to naught . . .
 
RE: A Solar Powered Ham Radio Station  
by WA1SFH on July 4, 2019 Mail this to a friend!
Re: Lithium Batteries.
It all depends on which "Lithium" CHEMISTRY battery you are using.

The good news is that the latest chemistry,Lithium Iron Phosphate (LiFePO4, will not burn or explode.
It also has a much improve discharge curve.
Check out: www.bioenno.com
 
How to Select the Battery Technology  
by DL4NO on July 6, 2019 Mail this to a friend!
As always: Decide first what you wish to build. Then plan something that satisfies you. There are many ways to reach different goals.

If you wish to be prepared for emergencies, lead batteries are the way to go: You get the most capacity for your money and normally you will only use perhaps 20% of your capacity. That will give you far more than 1,000 charging cycles, i.e. many years of service. But you must make sure that the batteries are more or less full most of the time. Empty lead batteries loose lots of capacity very fast.

If you are sure that your lead-gel battery was well cared for, you can try to refill some demineralized water every 3-5 years. This is quite easy to do. The battery in my computer UPS is quite well after 8 years of service.

It is quite easy to get lead-gel batteries more or less for free: In commericial UPS or alarm systems, the batteries must be replaced every 3 years. Unless your grid is quite unstable, these batteries were always charged and hardly ever discharged. If an UPS was active more than 100 times or so, the battery might have lost quite some capacity.

All other battery technologies cost a multiple of lead batteries per kWh capacity. They are only interesting if space and weight are very important or if you intend to use much of the capacity very often. A typical example is a house where someone lives and that is off-grid.

Another point of view: Only lead batteries are recycled in a larger scale. At least here in Germany 95% of all lead batteries are recycled. And I mean "recycle", not "downcycle": You can produce new batteries from them. Most often "recycling" means "create lower-quality produce from lower-quality raw materials".
 
Selecting Solar Modules  
by DL4NO on July 6, 2019 Mail this to a friend!
Solar modules get cheaper very rapidly. These days you pay less than 1 US-$ per Wp (Watts of output from sunlight with 1 kW/m2 at a module temperature of 20C). You can get them even cheaper as there is a market for used modules.

The used modules are quite often from "repowering", i.e. replacement of old modules with a higher efficiency. Or a solar power array was damaged by lightning or other influences. All modules within an array must have quite uniform characteristics and it is difficult to replace old modules with modules with the same form factor (modern modules are much larger) and comparable electrical data.

If you only need a hand full of modules, try to buy them used and locally. Then, for a large part ignore the rule that the modules must be carefully directed to the sun.

You need not worry if your house ridge is directed N-S. Especially if you wish to charge batteries, this is the better way: Theoretically, you get less output. But you get it over al longer time of the day. And when it is overcast, you might only get 5% or 10% of the maximum output, but you get more than with a conventional placement. And also consider the cost of all the mounting!

This two-part placement is even better if you primarily wish to charge batteries: The charging current of any battery must be limited. You higher output might therefore not help. But a longer charging time helps.
 
RE: Selecting Solar Modules  
by VK5SW on July 6, 2019 Mail this to a friend!
G'day Everyone from down under.
Thanks for the info about solar systems. Obviously, your knowledge far out weighs mine.
I would just like to say though, that the lead acid battery in the picture at the top of this article is still in use with never having had any problems at all. The only upkeep has been the topping up of distilled water in the cells. I bought that battery in 2007. From memory, I think I paid about Aus.$1500 at the time and it has been in sporadic use all that time, about 11 years now and still going. 73. Rob.
 
Batteries  
by DL4NO on July 6, 2019 Mail this to a friend!
Hello Rob,

thank you for your rapid response. My activities on this topic started in 2018 with two goals: Learn more about these technologies and build an emergency power supply for my shack. As a radio amateur I had to experiment and it did not hurt that I am an electronics engineer. :-)

I have published about this topic, but until now only in German: "Allzeit bereit? Gedanken zur Notstromversorgung im Shack (1). In: Funkamateur 2/2019, S. 130ff", part 2 in Funkamateur 3/2019, S. 240ff.

If you have some command of German you can even see a presentation on the topic I did last spring: https://www.youtube.com/channel/UCabJ1rQTfgko0sL-RT2jJNg.

My ideas about the handling of lead-gel batteries you find at http://www.dl4no.de/thema/vomumgan.htm. Here Google might help you with a translation.


73,
Alexander
 
Selecting Solar Controllers  
by DL4NO on July 6, 2019 Mail this to a friend!
Most cheap solar controllers have two tasks:

- Limit the battery voltage.
- Prevent that the battery voltage is fed back into the solar modules.

The biggest problem here is that the solar modules have a certain voltage where they provide the most power and this voltage depends on several factors.

Many solar modules are rated at 18 V. But this is valid at 20C. But especially in the summer, solar modules can heat up to 60C and more. Now remember that electrically a solar cell is a silicon diode operated in forward direction. Therefore each single solar cell has a temperature dependency of -2 mV/K.

Now multiply 36 cells * 40 K * 2 mV/K = 2,88 V or about 3 V less!

If you wish to get your lead battery full, you need up to 14.5 V. In the summer your solar module provides 18 V - 3 V = 15 V. So you only have 0.5 V for the diode in the solar controller and the voltage drop in your wiring. This at least cries for lots of expensive copper!

The alternative is another solar controller technology, called "maximum power point tracking" (MPPT). These controllers contain a switching voltage regulator and a microprocessor that permanently determines the solar module voltage with the highest power output. Here you typically use 36 V modules or 18 V modules in series.

This has several advantages: The current of the solar modules is much lower, you need much less copper. And as long as the solar voltage is higher as the battery voltage, the battery gets charged. If it is overcast and the two 18 V module provide only 12 V each: It does not matter. You only get 5-10% of the rated power, but you get power over looong times when standard solar controllers would provide hardly any power at all. At least you always have fully loaded batteries at all times.
 
RE: Selecting Solar Controllers  
by VK5SW on July 6, 2019 Mail this to a friend!
Hello Alexander,
Well, I can see that you are very well suited to your job. I am no where near as capable as you mentally in that respect. It will take me a while to digest the information.
73 Rob
 
Fuses in a Solar Powered Ham Radio Station  
by DL4NO on July 15, 2019 Mail this to a friend!
As the topic came up, I decided to add my 2 cents to it...

The basic rules are:

1: Any cable behind a fuse must be able to carry the maximum current of the fuse.

2: Especially in low-voltage systems: Every circuit behind a fuse must be able to blow that fuse.

About 1: That is not so obvious as you might think. For example: You have a preamp and you inserted a 1 A fuse in the plus line.

Now think about the following: The plus line of the TRX has a 30 A fuse. TRX and preamp are connected by a coax cable. What happens if the minus line of the TRX gets interrupted? The TX tries to find its return path through the minus line of the preamp. And you thought you had a 1 A fuse in this circuit...

The solution: Remove the minus line of the preamp. It can use the minus line of the TRX through the coax cable.

About 2: 10 V / 20 A = 0.5 Ohms. That is not much! This is why many of those cheap, thin 12 V extension cables are so easily combustible: 10 V * 20 A = 200 W!

About fuses on batteries: I have a fuse within 30 cm of any of my lead-gel batteries. And if you use several batteries in parallel, the main power line must be able to carry the sum of all those fuse currents!

I most often use 15 A fuses. Two batteries in parallel are enough for a 100 W RX. If you have 4 batteries in parallel this means the battery rail must be able to cope with 60 A!

Normal car batteries have a surprisingly high resistance. They easily have several 100 mV of voltage drop before they blow. So I try to use no more of them in series than absolutely necessary. But that might mean 3 fuses in series for a thin wire.
 
Fuses in a Solar Powered Ham Radio Station  
by DL4NO on July 15, 2019 Mail this to a friend!
As the topic came up, I decided to add my 2 cents to it...

The basic rules are:

1: Any cable behind a fuse must be able to carry the maximum current of the fuse.

2: Especially in low-voltage systems: Every circuit behind a fuse must be able to blow that fuse.

About 1: That is not so obvious as you might think. For example: You have a preamp and you inserted a 1 A fuse in the plus line.

Now think about the following: The plus line of the TRX has a 30 A fuse. TRX and preamp are connected by a coax cable. What happens if the minus line of the TRX gets interrupted? The TX tries to find its return path through the minus line of the preamp. And you thought you had a 1 A fuse in this circuit...

The solution: Remove the minus line of the preamp. It can use the minus line of the TRX through the coax cable.

About 2: 10 V / 20 A = 0.5 Ohms. That is not much! This is why many of those cheap, thin 12 V extension cables are so easily combustible: 10 V * 20 A = 200 W!

About fuses on batteries: I have a fuse within 30 cm of any of my lead-gel batteries. And if you use several batteries in parallel, the main power line must be able to carry the sum of all those fuse currents!

I most often use 15 A fuses. Two batteries in parallel are enough for a 100 W RX. If you have 4 batteries in parallel this means the battery rail must be able to cope with 60 A!

Normal car batteries have a surprisingly high resistance. They easily have several 100 mV of voltage drop before they blow. So I try to use no more of them in series than absolutely necessary. But that might mean 3 fuses in series for a thin wire.
 
Fuses in a Solar Powered Ham Radio Station  
by DL4NO on July 15, 2019 Mail this to a friend!
As the topic came up, I decided to add my 2 cents to it...

The basic rules are:

1: Any cable behind a fuse must be able to carry the maximum current of the fuse.

2: Especially in low-voltage systems: Every circuit behind a fuse must be able to blow that fuse.

About 1: That is not so obvious as you might think. For example: You have a preamp and you inserted a 1 A fuse in the plus line.

Now think about the following: The plus line of the TRX has a 30 A fuse. TRX and preamp are connected by a coax cable. What happens if the minus line of the TRX gets interrupted? The TX tries to find its return path through the minus line of the preamp. And you thought you had a 1 A fuse in this circuit...

The solution: Remove the minus line of the preamp. It can use the minus line of the TRX through the coax cable.

About 2: 10 V / 20 A = 0.5 Ohms. That is not much! This is why many of those cheap, thin 12 V extension cables are so easily combustible: 10 V * 20 A = 200 W!

About fuses on batteries: I have a fuse within 30 cm of any of my lead-gel batteries. And if you use several batteries in parallel, the main power line must be able to carry the sum of all those fuse currents!

I most often use 15 A fuses. Two batteries in parallel are enough for a 100 W RX. If you have 4 batteries in parallel this means the battery rail must be able to cope with 60 A!

Normal car batteries have a surprisingly high resistance. They easily have several 100 mV of voltage drop before they blow. So I try to use no more of them in series than absolutely necessary. But that might mean 3 fuses in series for a thin wire.
 
Fuses in a Solar Powered Ham Radio Station  
by DL4NO on July 15, 2019 Mail this to a friend!
As the topic came up, I decided to add my 2 cents to it...

The basic rules are:

1: Any cable behind a fuse must be able to carry the maximum current of the fuse.

2: Especially in low-voltage systems: Every circuit behind a fuse must be able to blow that fuse.

About 1: That is not so obvious as you might think. For example: You have a preamp and you inserted a 1 A fuse in the plus line.

Now think about the following: The plus line of the TRX has a 30 A fuse. TRX and preamp are connected by a coax cable. What happens if the minus line of the TRX gets interrupted? The TX tries to find its return path through the minus line of the preamp. And you thought you had a 1 A fuse in this circuit...

The solution: Remove the minus line of the preamp. It can use the minus line of the TRX through the coax cable.

About 2: 10 V / 20 A = 0.5 Ohms. That is not much! This is why many of those cheap, thin 12 V extension cables are so easily combustible: 10 V * 20 A = 200 W!

About fuses on batteries: I have a fuse within 30 cm of any of my lead-gel batteries. And if you use several batteries in parallel, the main power line must be able to carry the sum of all those fuse currents!

I most often use 15 A fuses. Two batteries in parallel are enough for a 100 W RX. If you have 4 batteries in parallel this means the battery rail must be able to cope with 60 A!

Normal car batteries have a surprisingly high resistance. They easily have several 100 mV of voltage drop before they blow. So I try to use no more of them in series than absolutely necessary. But that might mean 3 fuses in series for a thin wire.
 
Fuses in a Solar Powered Ham Radio Station  
by DL4NO on July 15, 2019 Mail this to a friend!
As the topic came up, I decided to add my 2 cents to it...

The basic rules are:

1: Any cable behind a fuse must be able to carry the maximum current of the fuse.

2: Especially in low-voltage systems: Every circuit behind a fuse must be able to blow that fuse.

About 1: That is not so obvious as you might think. For example: You have a preamp and you inserted a 1 A fuse in the plus line.

Now think about the following: The plus line of the TRX has a 30 A fuse. TRX and preamp are connected by a coax cable. What happens if the minus line of the TRX gets interrupted? The TX tries to find its return path through the minus line of the preamp. And you thought you had a 1 A fuse in this circuit...

The solution: Remove the minus line of the preamp. It can use the minus line of the TRX through the coax cable.

About 2: 10 V / 20 A = 0.5 Ohms. That is not much! This is why many of those cheap, thin 12 V extension cables are so easily combustible: 10 V * 20 A = 200 W!

About fuses on batteries: I have a fuse within 30 cm of any of my lead-gel batteries. And if you use several batteries in parallel, the main power line must be able to carry the sum of all those fuse currents!

I most often use 15 A fuses. Two batteries in parallel are enough for a 100 W RX. If you have 4 batteries in parallel this means the battery rail must be able to cope with 60 A!

Normal car batteries have a surprisingly high resistance. They easily have several 100 mV of voltage drop before they blow. So I try to use no more of them in series than absolutely necessary. But that might mean 3 fuses in series for a thin wire.
 
A Solar Powered Ham Radio Station  
by AH6FC on August 4, 2019 Mail this to a friend!
Solar is good...depending on your utility costs. In Hawaii, even with 40 cents/KwH, the cost of full solar, off grid is still marginal. We did it, because I don't want to pay the rip off utility, at 40 cents/KwH. However, it's still a 8 year payoff, even with AC.


Alternative energy, if it makes you feel good great. However the bottom line $$/Cents evaluation is not to be ignored. Many places, on mainland USA and probably elsewhere, have costs of 3 - 15 cents/KwH....my guess is at those rates it will never make sense to go solar/off grid....assuming you have access to grid electricity
 
RE: A Solar Powered Ham Radio Station  
by DL4NO on August 4, 2019 Mail this to a friend!
There are many motives to do more or less with solar energy.

Many people over here fill all of their roofs with solar modules and feed most of that energy to the grid.

Others try to store as much of their solar energy as possible for their own use. It gets extremely expensive to draw less than 10% of your energy from the grid.

If your QTH is off-grid, you have not so many alternatives. Some normal generator is quite expensive to operate and very noisy.

My main motive is to have some energy if the grid should fail for more than a few hours. Most of that energy will be dedicated for ham radio: Without the power grid you cannot use your land line phone, the Internet or your cell phone. We hams can communicate nevertheless.

BTW: Here in Germany the mean power outage per year is about 15 min.
 
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