How Many Watts Do You Leave On The Table? (Small Systems)

emt27 said:

Never thought of waste... now I can't stop thinking about it. I have 4 12v batteries wired in 24v system. Sorry haven't worked out the math

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Not all production goes to 'Waste', some will be absorbed by equipment losses,
Losses are a fact of life and simply the price you pay for having electricity...
Instead of donkey power , anything that comes out of the donkey is also waste, but both will bite & kick!

When we 'Over Panel' for battery charging on not optimal sun days, we leave that power on the table once batteries are charged on full sun days,

When we throttle the power from panels through a charge controller with 30 Amp maximum,
Corvette power panels, Lawnmower power charge controller...
*IF* you have Corvette batteries that charge quickly, the Corvette power from panels on the roof are perfectly capable of making big power,
Some batteries are not capable of charging at high rates/quickly, and that makes a difference.
Simply trying to point out you CAN use that power with common components...

Batteries FIRST, and always.
Follow that one rule, then you can do what you want with something as simple as a timer.

Connected charge controller and appliances (Loads), like those connected wall outlets and power switchs, you could find out remotely when your batteries hit 100% SOC and you could turn on applainces remotly.
I'm NOT the connectivity type, so I couldn't stop a timer I set while at work when an unexpected/forcast storm or clouds popped up, that's where my battery reserve comes in, but batteries cost big money...
Someone tech savvy could get along with less battery with connected monitoring and control over load.
(Instead, they would spend money on a fancy phone & remote power controls, connected charge controllers, etc.)

Being NON-connected (read: Old Fart) and having been off grid for 20+ years, I use something like this for washing machine, etc.
Load the washer, set the switch to 'Auto' and let the washer work after the batteries *Normally* charge.
I have one in the kitchen to start crock pot dinner or something like that.



We have been so accustomed to living off grid, wall light switches look like this,
No lights/appliances left on by mistake.
This mechanical version doesn't suck any Watts like motion sensors or digital timers do.

@JeepHammer I like the idea of turning things on when SoC is 100%, especially if before a certain time (when you likely are still generating PV). I'll consider that in IoTs optimization. Thanks, once again, for your perspective.

While I'm still on utility power, I had a 3 hour outage Christmas Eve. That, combined with this thread, has me thinking about all the ways I can divert power.

Another untapped source of lithium storage: old laptops! lol Yeppers. I wiped the dust off an old Pentium III, and sure enough, it has lithium batteries so still holds a charge really well. It's a brick power bank. Not sure how I got it to go in a standby mode without the OS running, but that allowed me to charge a phone off its USB port without actually booting it up. Newer computers will have a setting in the BIOS that allow you to draw power from the USB while the computer is off.

These are the sort of things you'd want to charge up during those excess PV days, and drain by using as phone chargers, night lights, etc,..

BTW, I cringe at those timers for turning off hot showers so many times while camping. Don't mess with my hot showers!

emt27 said:

Never thought of waste... now I can't stop thinking about it. I have 4 12v batteries wired in 24v system. Sorry haven't worked out the math

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The person with just enough panels that just charge the batteries in about 5 hours (short winter sun) won't really have any over-production except in long, clear summer days...

While Will Prouse has fairly well balanced smaller designs,
Panel production is limited to about what the system & batteries eat,
That puts 100% of the load on the batteries.

*IF* someone catches on, can figure the production, figure or observe charge time, has batteries that won't take all peak sun hours to charge,
A little larger panels allows for direct use, and ability for charge controllers to put that REGULATED power on the inverter lines for use, there isn't really an issue with doing just that.

We aren't talking trying to use battery charge controllers and BIG extra power panels to power everything directly,
There are devices that protect both panels from there own over production, and safeguard the larger paneled systems, when you go WAY big, use those!

The MPPT charge controllers LIMIT top voltage to what's safe for the batteries,
Anything extra they put on the lines is REGULATED specifically to the Load, which is simply what you use up to the limits of the panel production, then you start pulling on batteries.

As long as the panels don't over volt, or over amp the charge controller, so it won't be damaged, it's perfectly safe to do, simply maximizing what the panels/charge controller/controllers can put on the main lines for use.

Every charge controller has a maximum voltage, and maximum amperage it can handle,
Your panels have to be wired so they can't exceed those specifications, so you have to the the watts/volts/amps conversion to see how the panels are most efficient and still say under the limits of the CC.

Notice in my diagrams I keep the panel production under 20 Amps, which is the limit for common MC4 connectors with 10 Ga wire.
(Some people say 30 amps/10 Ga, but the 10 Ga wire starts heating, wasting amps at 32.5 Amps, not nearly enough safety margin built in for my installs, panels CAN, and often do exceed their 'Rated' output)

With the new generation of batteries (low resistance, fast charge time) a charge controller for Lead/Acid might very well be leaving power on the table.
Adding batteries in the strings, but using a charge controller that was intended (amps pass through) a single battery might very well be drawing out charge time, as well as leaving power on the table.

It never hurts to run the numbers and see if you are leaving power on the table...

erik.calco said:

@JeepHammer I like the idea of turning things on when SoC is 100%, especially if before a certain time (when you likely are still generating PV). I'll consider that in IoTs optimization. Thanks, once again, for your perspective.

While I'm still on utility power, I had a 3 hour outage Christmas Eve. That, combined with this thread, has me thinking about all the ways I can divert power.

Another untapped source of lithium storage: old laptops! lol Yeppers. I wiped the dust off an old Pentium III, and sure enough, it has lithium batteries so still holds a charge really well. It's a brick power bank. Not sure how I got it to go in a standby mode without the OS running, but that allowed me to charge a phone off its USB port without actually booting it up. Newer computers will have a setting in the BIOS that allow you to draw power from the USB while the computer is off.

These are the sort of things you'd want to charge up during those excess PV days, and drain by using as phone chargers, night lights, etc,..

BTW, I cringe at those timers for turning off hot showers so many times while camping. Don't mess with my hot showers!

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I jump started (boosted) my old Jeep off an 18 volt cordless tool battery and a local guy saw me do it.
Then later on he raked me over the coals because when he tried it on his wife's car it cost $1,400 to get the car fixed.
Seems some components of that COMPUTER vehicle wouldn't withstand 18 Volts, even momentary...

I have USB transformers/outlets laying around here, I install them in things like my Harley builds, old Jeeps, Radio battery packs, etc
There will always be USB charged devices around no matter what we are doing, so why not have a couple USB converted outlets, I mean they are like $5 each on eBay, and the ones I get have flush install mount faces for permanent install, nothing shows but the USB slot...

I've seen them in 9 volt, 12 volt, 16 volt, 18 volt, 24 volt, 36 volt & 48 volt DC,
120 & 240 AC, all cheap...
(16 volt & 18 volt still have me scratching my head)

I don't get the wall mounted LED 'Emergency' lights with weights and all that,
It takes 3 Watts to bring some LEDs to life,
Wouldn't a hand crank be a lot more simple to operate?
I have an old, cheap plastic hand crank LED flashlight I glued a magnet to, 30 seconds of crank get 10 minutes of light and it's sticks to any magnetic surface.
No dead batteries ever...

The idea of the laptop battery was GREAT!
A damn sight more than 3 Watts hiding in there too!
Having a regulated power source for USB charging is stupid handy since half the world seems to be USB powered these days!

JeepHammer said:

Having a regulated power source for USB charging is stupid handy since half the world seems to be USB powered these days!

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Add to that 18650s. You can get "DIY power banks" on ebay that can take up to 8 cells. My 18650 charger also has a USB out, doubling as a power bank with 1 to 4 cells in it. I used it during that 3 hour power failure because I have a lot of 18650s lying around.

These are small use cases. But, when in conservation mode, 5V applications are very useful. The first thing I did when my power was out was shake my phone, using it as a flashlight so I could turn other things on. If my main internet is down, my phone can act as router. I then use Chromebook connected to it to get online. So, at that point, USB power becomes important. The phone needs extra juice to act as a wifi router.

To be sure, I got my inverter online the day after Christmas with my 24V bank. But, the lightest circuit I can run with that via my transfer switch happens to be the one I use to charge my phones and tablets, next to my couch, where I can comfortably watch Netflix on my Chromebook.

In March, I'll have my PV charging, and begin to hopefully deal with excess PV capacity. Along the lines of your point, I plan to flip on whatever circuit makes the most sense for absorbing the level of production I'm getting that day. You could potentially dedicate an entire circuit to excess production absorption if your inverter can handle it, then one day automate turning that on.

Actually, I was mistaken. My SCC is 50 Amps, not 30A like your 1st diagram, and I will be adding the 3rd (starting) battery, so a lot more possible left on table. I won't know until I finish my project and get it in the vehicle...I'd rather have too much than too little any day.

erik.calco said:

Add to that 18650s. You can get "DIY power banks" on ebay that can take up to 8 cells. My 18650 charger also has a USB out, doubling as a power bank with 1 to 4 cells in it. I used it during that 3 hour power failure because I have a lot of 18650s lying around.

These are small use cases. But, when in conservation mode, 5V applications are very useful. The first thing I did when my power was out was shake my phone, using it as a flashlight so I could turn other things on. If my main internet is down, my phone can act as router. I then use Chromebook connected to it to get online. So, at that point, USB power becomes important. The phone needs extra juice to act as a wifi router.

To be sure, I got my inverter online the day after Christmas with my 24V bank. But, the lightest circuit I can run with that via my transfer switch happens to be the one I use to charge my phones and tablets, next to my couch, where I can comfortably watch Netflix on my Chromebook.

In March, I'll have my PV charging, and begin to hopefully deal with excess PV capacity. Along the lines of your point, I plan to flip on whatever circuit makes the most sense for absorbing the level of production I'm getting that day. You could potentially dedicate an entire circuit to excess production absorption if your inverter can handle it, then one day automate turning that on.

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I run into connectivity (routers) more & more...
My hillbilly 'Solution' was to look at the transformer, and if it was 12 Volt output, power problem solved, got wired directly to battery Voltage in 12 Volt systems, just took the 120vac transformer out of the circuit.

The 'Plug & Play' version of that, which I'm not crazy about, is a much smaller inverter, like the cup holder inverters that only throw 75-150 Watts connected to 12 volts, and wireless router plugged into that.

When all the power in the home is 120/240vac, and the solar batteries are out in the 'Barn' (or wherever),
A battery backup with with router only plugged into it.
Most have little gel cells, but powering JUST the router it will run for quite a while.

Santa said:

Actually, I was mistaken. My SCC is 50 Amps, not 30A like your 1st diagram, and I will be adding the 3rd (starting) battery, so a lot more possible left on table. I won't know until I finish my project and get it in the vehicle...I'd rather have too much than too little any day.

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50 Amps × 12 Votls = 600 Watts/Hour for you to run things on without damaging the batteries, or drawing off your charged batteries.
The issue in your case is 4ea, 100 watt panels, so you will be limited to 400 Watts after controller (and inverter) losses.
Controller losses if you use it as 12 Volts DC, controller & inverter losses if you use it as 120vac.

I know I'm erratic many times, and don't get my point across effectively...
But what I would like is the more knowledgeable guys with up and running systems to gauge the input to charge controllers so we know what the panels are capable of producing in Watts,

And gauge what actually comes out of the charge controller,
Particularly when batteries are discharged and controllers are working their hardest.

I've tried twice on this forum (and many others) to get some real world readings of efficiency from folks.
About everyone knows exactly what brand their panels are and what they are rated for.
About everyone knows he make/model of the charge controller so we can easily find those specifications.

What we need is real world data about how old the panels are and how much they produce, feed to the controller,
The 'Before', and what actually gets through the controller, the 'After', and all we need is the numbers off 2 watt meters with memory, we can crunch the numbers...

This would let us figure losses in the equipment.
It would also give us an idea what controllers live the longest, which panels put out fill production with age, etc.

I *Assume* I'm the odd ball on this, I stuck meters in to see what my losses were, but a sample of ONE does nothing for nobody...

erik.calco said:

The stator?

https://alternatorconversions.com/

Alternative approaches:

View attachment 4309 View attachment 4310

source: Solar-Rains-Wind-Lightning Energy Source Power Generation System (pdf)

I can hear your crazy wheels turning now.

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YOU BET! ?

I know exactly how I want to test this...

You can't fence off all the way to the river, and I have a guy in a big 4x4 that likes to drive my riverbank once in a while, but he tears down through there, stops and digs big ruts, has dumped trash twice, and I just haven't caught him yet...
He made TWO passes through my 4' tall sweet corn just to make sure he got it all.?


How about nailing his hands & feet together on the shop roof and sticking an aluminum ball bat in his butt in a stormy night? I'll spring for a cheap power meter to see what he produces...

I'm thinking of planting sweet corn down there again this year, but around one of those triangle shaped tank barriers they used during WWII...
Maybe put a one of those plastic garden owls on a broom handle sticking up so it's irresistible...

Yes, I have a mean streak once in a while...
I'd MUCH rather be making friends and working on something challenging & constructive, it's just in my nature to build.
Some people are builders, some people are users, some people are destructive in nature.
I throw tools in the truck and the wife says, "Where are WE going?"
I say to help someone with something, she wants to know if they have wife, kids, etc so she can take along treats and make new friends...
There is a reason I like the guys on this forum, they are learners, teachers & builders!

JeepHammer said:

What we need is real world data about how old the panels are and how much they produce, feed to the controller,
The 'Before', and what actually gets through the controller, the 'After', and all we need is the numbers off 2 watt meters with memory, we can crunch the numbers...

This would let us figure losses in the equipment.
It would also give us an idea what controllers live the longest, which panels put out fill production with age, etc.

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If I implement the IoTs, we'll be able to feed the cloud with data, combining it to help us learn.

erik.calco said:

If I implement the IoTs, we'll be able to feed the cloud with data, combining it to help us learn.

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I'd settle for just having a reasonable recommendation for guys on the beginner forums that's NOT sales propaganda...

It's not like the manufacturer/sales staff isn't going to put their products in the best possible light...
That's what I'm liking about Will Prowse videos, he takes the stuff apart, tests in side by side, gives recommendations on what showed best promise.

Unless you had every product in use for 20 years, no way to say how long it's going to hold up...
Most of the stuff we see wasn't on the market 5 years ago, so longevity is still a crap shoot, but using components that look promising is a good start!

I don't want to filter through years of daily production on MY OWN stuff, so just some peak sun hour, single data points would be helpful...

Yeah, I get it. Anything is better than nothing.

I actually already created the data collection service a few years ago. I called it Cloud Collector. But, it's not live in production currently because it costs money to run it.

When it is live, and we have things to feed it, it will be EASY. If your device can get to the Internet via wifi or bluetooth (via mobile proximity), it can just automatically send it. Otherwise, I might develop something so you can plug in a memory card and update the cloud. Once in the cloud, a user would have control over the data and view their own reports, but could offer some form of sharing, either anonymous, or inter-personal, where person A shares with person B. If we have anonymous aggregation, then we can learn from everyone's data. But, I'm a long ways from developing those capabilities. Right now, it is just an interface that can be used by services to push large quantities of data -- aka Internet of Things (IoT) data.

I get the storage part, but what crunches the numbers from different programs/platforms?

The guy that goes $25-$30 into a couple power displays, snap a few pictures of what's input and what's output, let us know if it's full sun, a few clouds up high, and that's stupid easy.
Those $10 power meters show volts, amps, Watts, so it's pretty easy to tell how many watts you are making and how many are making it through to the batteries/inverter lines.

AND, you can do that on the low end, non-connected charge controllers.
Most certainly low tech, but still effective.
Until someone sets industry standards and everything identifies itself to the central information processor, it's not going to be 'Plug & Play' like computers are now.

It's even harder with inverters, unless you have a calibrated load on the AC side, its difficult to determine what the efficiency of any given inverter is. Very few will even bother with advertising an efficiency rating, and most won't even tell you want the stand by consumption is when it's sitting idle.

You know a LOT more about it than I do, I'm as 'Low Tech' as I can possibly get away with...

It's not 'Tech Phobia', it's a longevity issue.
KISS, "Keep It Stupid Simple", and use common parts that will still be on the market 30 years from now.
Build so 'Bubba Thumbuster' can do the maintenance, because 'Bubba Thumbuster' is exactly who is going to being beating on it with a hammer instead of someone that has training...
(People with training cost more)

You have seen people scoff at a Rheostat instead of something higher tech, but a Rheostat is 2 wires and Stupid Simple, has been available for 150 years, and is still available at autoparts stores.

You have seen people scoff at using sun tracking, saying panels are "Too Cheap",
Buy a 'Cheap' panel, get a Cheap panel, and replace it every couple years...
Good panels cost good money, sun tracking costs what one better panel does, but saves you 20%-30% every day.

What I see is people buy 'Connectivity' and watch things about a month, get bored and play 'Candy Crush' instead.
Solar production is BORING, you can't see big machines move, just some numbers on a display.
If I actually WANTED to see that, I'd go to work!

When every display is turned on, with all the operational LED lights built into everything, it looks like a 70's disco on the power wall!
Most of my monitor stuff is turned off, a habit when a 120 watt panel was a HUGE deal, and $400, but after 20 years I just want to know what's going on once a week or once a month, and I learned those displays both suck power (back to 40-60-100 watt panels being 'Big' and trying to keep lead acid batteries alive),
AND the displays left on DID burn out over time, need to be replaced (longevity issue).

Everything has changed, most for the better, but I'm still looking 20 years down the road,
If I buy the latest-greatest whiz-bang item today, will the manufacturer be there in 2, or 10 years when I need service or replacement?

I'd LOVE it if everything was plug & play, and connected so I didn't have to manually check up on it, but it just isn't...
YET...
And *IF* there was a common collection program that crunched the numbers, could you trust the PUBLISHED results?
Microsoft collected failure data on everything, but wouldn't release numbers on it's OWN fails...
Instead advertising it was the 'Most Stable' and 'Trouble Free' platform.
Anyone that has had the blue screen of death, or spent countless hours shutting down and rebooting Microsoft platforms tends to think differently...
The Linx (or however it's spelled) used to fall out of their chairs laughing when those advertisment cam on TV...

You know a BUNCH more about it than I do, so if you can shed light on how to get something like this going I'm all ears! (And I do have big ears, and nose too!)

JeepHammer said:

Those $10 power meters show volts, amps, Watts, so it's pretty easy to tell how many watts you are making and how many are making it through to the batteries/inverter lines.

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It would be a $30 version of that $10 power meter. ? It would be dirt easy.

To give an example, I have a Garmin watch that collects GPS and altitude when I jump. When I am back on the ground, my phone picks it up via bluetooth and automatically puts it into the cloud.

erik.calco said:

It would be a $30 version of that $10 power meter. ? It would be dirt easy.

To give an example, I have a Garmin watch that collects GPS and altitude when I jump. When I am back on the ground, my phone picks it up via bluetooth and automatically puts it into the cloud.

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OK, clue me in...
I'm not adverse to spending $$ for community good...

Now, if it hits $$,$$$.¢¢ that's something I probably wouldn't do.

I'm the kind of guy that has the accountant run my taxes twice,
Once straight up, once with donations to the children's hospital.
Writing a check to the children's hospital where it does direct good other than the government where I know 90% will be wasted seems more ethical to me, and better use of my money...

That's one of my jumps....

I'm not connecting this to solar data collection, how would that work?
What's the $30 interface for any system?

I'm aware of Bluetooth, Wi-Fi connections, but what collection system would compile data input?
What is the $30 hardware that would make that data collection and transmit it?

It would have to have connection points to panels, and to the battery, stand alone so it could sample both, and transmit the collected data, the hardware is what I'm talking about, the collection/transmitter.

Sorry, didn't read the whole thread, TLDR but it seems that you're looking for solar system analytics. Imho, there are three options:

1. DIY analytics. There are just hundreds of IoT analytics platforms out there, from commercial offerings like Amazon IoT, to hobbyist platforms like ITTT.com, adafruit.io etc. What you measure is entirely down to you, they just provide the means to transport, capture and display.
2. Open analytics. These are open platforms that merge data from hundreds/thousands of consumers. Last one I saw was a 'solar road' platform where hundreds of different 'solar road' installations all uploaded their data. Google 'open solar analytics'.
3. Propriety analytics. These are usually offered by a particular manufacturer, for example, I personally use Victron VRM. My Color Control GX collects data from the inverter (MultiPlus i.e. DC/Mains/Genset), charge controllers, battery monitor, temp sensors etc and uploads all this to VRM where you can analyse your usage over time, set alarms, share data etc

JeepHammer said:

I'm not connecting this to solar data collection, how would that work?

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If data can be transmited, then it first must be locally stored. For example, my Victron Color Control GX stores its data an an internal flash memory card, you can access it via connecting to its internal web server and downloading e.g. CSV files.

JeepHammer said:

What's the $30 interface for any system?

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Don't know but, for example, I use an Adafruit 'Adalogger Feather M0' to monitor current drain on my car (I'm trying to figure out why my battery keeps going flat after a few days). It uses a high-side current sensor and logs data to a SD card I can then analyse on my computer.

JeepHammer said:

I'm aware of Bluetooth, Wi-Fi connections, but what collection system would compile data input?

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There are hundreds of such online platforms, just Google 'IoT analytics'.

JeepHammer said:

What is the $30 hardware that would make that data collection and transmit it?

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Not sure on commercial product offerings, I always make my own devices using, for example, a simple microcontroller. Google 'ESP8266'. This is a ubiquitous IoT/microcontroller chip used in literally thousands of products i.e. it can collect data from sensors then transmit this securely via WiFi.

JeepHammer said:

It would have to have connection points to panels, and to the battery, stand alone so it could sample both, and transmit the collected data, the hardware is what I'm talking about, the collection/transmitter.

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A typical IoT system:



Sorry for the naff handwriting.

I hope this helps.
Regards,
David.

Well, to get someone to bother with it, there would have to be benefit TO them.
An email or text when production goes low while other local systems in their area are NOT showing low or no production (weather related),
And it couldn't annoy the crap out of the owner/user, who wants to know everytime a cloud passes over or a bird lands on the panel frame and shades it?

I think thresholds is the the correct term...

I would IMMEDIATELY want to know if full panel production hit the battery cables (charger/controller failure), another threshold/alert requirement in the software.

Stupid simple user interface would be a requirement for me, I'm about as stupid as they come when the 'Simple' (Monitoring/controls) displays have 20 screens with a 100 different setting shows up...
I just ignore everything and find a mechanical solution...

Marketed as a safety device, with a reasonable price so small 'Dumb' systems can be remotely monitored and alerts to problems issued would make it sell.
I know from first hand experience that the 'Theater' of sales propaganda is more likely to make or break a product than what that product, or improvement to a product actually does to the consumer market.
Make it seem like a safety issue would be a selling point, and a monitor interface that wasn't stupid complicated would be another selling point...

I would actually throw money at a start up for something like this, I think it's marketable if the correct people were involved, but what do I know, I still have a stock certificate for $1,500 of Commodore Computer to remind me of what NOT to do again...

You nailed my marketing plan, JeepHammer, future VP of Marketing. LOL

*IF* you wanted an actual marketing plan, sell at low cost (break even, which is about 35% over ALL costs) get people signed up & logged on, probably by zip code so you can compare average production drops due to weather,

On free sign up, get battery make/model/number, charge controller make/model, and panel make/model/number.
Then tie production figures with make/model of whatever...

*IF* it catches on, then start selling with a monthly or yearly fee to make money, previous buyers get a 'Free Year'.
OR,
Manufacturers that rate well can pay a fee to say they did really well with *Solar Safety Monitor* or what ever the name is.
Maybe pay to get on a list that (gets recommended) shows up as doing well by the numbers they produce.
A 'Top 10' best producing scroll when they look up their system.

JeepHammer said:

*IF* you wanted an actual marketing plan, sell at low cost (break even, which is about 35% over ALL costs) get people signed up & logged on, probably by zip code so you can compare average production drops due to weather,

On free sign up, get battery make/model/number, charge controller make/model, and panel make/model/number.
Then tie production figures with make/model of whatever...

*IF* it catches on, then start selling with a monthly or yearly fee to make money, previous buyers get a 'Free Year'.
OR,
Manufacturers that rate well can pay a fee to say they did really well with *Solar Safety Monitor* or what ever the name is.
Maybe pay to get on a list that (gets recommended) shows up as doing well by the numbers they produce.
A 'Top 10' best producing scroll when they look up their system.

Click to expand...

That's very much inline with a different business I'm launching in the next 2 months. A free browser-based trading system with what I believe is the biggest retail US broker for equities, which happens to offer free commissions now. It may be limited to US customers only for now.

I'm hoping to keep it free, while offering optional subscription services on top of it. The free tier will actually be very powerful. The reason I can offer it for free is my cost for running it will be very low. Although, it has cost a lot of hours to develop. The subscription services, on the other hand, will cost a lot to host.

I hope to have something similar for IoT for Solar, though its cost structure is very different because it includes hardware. On the service side, these two businesses can share the back-end technology (e.g., Cloud Collector, billing), so that the success of one opens the door to launching the other because it will lower the marginal cost of the services.