Living offgrid with small solar system(s)

[Naam]

So now we know why Naam built his pool indoors. To save electricity. That's why he has so much money.

having lived more than half of our lives in tropical countries, both wife and me hate the sun. that's our reason for "indoor".

[KonaRain]

Same latitude. .I hate Sun also..vitamin d?

Re: tesla..can't we just choose how many LifePo4's we need, and buy a hundred dollar inverter..?

[Gary A]

I have always wondered why the people who invent the gadgets that are guaranteed to give you 30 percent better fuel economy don't sell them to the automotive companies.

a former neighbour of mine (Florida) swore all holy oaths that the additive he is using ($19.95 plus shipping, handling, tax, tag and title) reduces his gasoline consumption by 35%

comments from my wife "Bob is such a nice and polite chap! why argue?"

In situations like your neighbor, it helps a lot to have a good imagination. When you tell the same BS all the time, eventually you believe it yourself. Then there are many people who will swear to the impossible because they refuse to admit that they made a mistake. I know a guy who paid $39.95 for some sort of gadget to increase his diesel Toyota fuel economy. After he installed it he went on a fairly long trip. When he got back I asked him about it. He admitted that it made absolutely no difference.

[Gary A]

If I had a swimming pool, I think I would have two separate systems. One that used a brush-less DC motor that ran totally off panels, no charge controller and no batteries. It would work well as long as I had sunny days. But knowing that it couldn't do the job by itself, I could then use the regular grid system when needed. At least the solar part would save considerable electricity.

I have a bore hole with a one HP submersible pump. I had a 2,500 watt generator that ran the pump just fine after the start surge. My wife's uncle is a good electrician and he told me that the little generator would soon die. Now I have a 5,000 watt generator and it doesn't ever cough when the pump starts. I use the small one at home for very long power outages. I separated a 10 amp breaker that runs the refrigerator, all the lights, TV's and the home water pump. I have a double pole, double throw switch that separates the main power from the generator. Even my wife, who knows everything, cannot possibly make any problems with that setup. None of that crazy plugging the generator into an AC outlet. Just throw the switch from main power to the generator. When the main power power comes back on, just throw the switch back to the main.

Anyways, If/when the 5,000 watt gasoline generator or the pump dies I want to go solar with that. The farm is off the grid so I have no choice. My Kubota tak tak diesel delivers a LOT more water using very little fuel than the gasoline generator running the one HP pump. The solar system would pump directly into the pond and the diesel powered pump would pump out of the pond. After the bore hole was completed, my wife had her nephew bring a large piston pump over, powered by the tak tak. The bore hole is 50 meters deep and they couldn't understand why that pump wouldn't work. I tried to explain it but they kept fiddling with the pump. After a day and a half they decided that the piston pump was not going to work. I knew that I would need a generator and a submersible pump. So far it has worked well for several years. The generator is electric start so my wife can get it going with no problems even though she complains that the generator eats too much benzine. It gets run a couple times a week as long as we have no rain.

Yes, I am a big fan of solar power. If I ever get around to it, I want to add two more 250 watt panels to the two that are feeding the grid. I will disconnect the hard starting generator and hook that system to the ten amp breaker. I need batteries and two more panels. I already have the charge controller and inverter. I'd like to go bigger but there are too may trees.

[Naam]

I separated a 10 amp breaker that runs the refrigerator, all the lights, TV's and the home water pump. I have a double pole, double throw switch that separates the main power from the generator. Even my wife, who knows everything, cannot possibly make any problems with that setup.

when we lived in the African bush our setup was identical except that our switch was not flipped very often as we were fed 95% of the time by a 70kVA genset.

[George Harmony]

If I had a swimming pool, I think I would have two separate systems. One that used a brush-less DC motor that ran totally off panels, no charge controller and no batteries.

if i can find one that can do the job during peak hours for a pool of +/- 14.000ltr volume i will buy it tomorrow .....

Perhaps 2 ....

[Naam]

Same latitude. .I hate Sun also..vitamin d?

Re: tesla..can't we just choose how many LifePo4's we need, and buy a hundred dollar inverter..?

we would have loved to live in your neighbourhood. visited the islands several times, albeit for a few days only each time. most beautiful climate at higher altitudes!

[Muhendis]

Re: tesla..can't we just choose how many LifePo4's we need, and buy a hundred dollar inverter..?

Yep! 'course you can. If you get them from China don't forget to get a few spares..........

http://www.aliexpress.com/w/wholesale-lifepo4-battery-100ah.html

[Gary A]

A question for a good sparky. Would it work if I would connect a 500 watt grid tie inverter to the the AC side of an 800 watt off grid battery powered inverter. The grid tie inverter needs to see line voltage or it will shut down. I'm afraid to try it without some advice. That would allow the charge controller more power to charge a bigger battery bank. I could then add batteries to my battery bank and use more power from the battery bank when the sun goes down.

[Crossy]

A question for a good sparky. Would it work if I would connect a 500 watt grid tie inverter to the the AC side of an 800 watt off grid battery powered inverter. The grid tie inverter needs to see line voltage or it will shut down. I'm afraid to try it without some advice. That would allow the charge controller more power to charge a bigger battery bank. I could then add batteries to my battery bank and use more power from the battery bank when the sun goes down.

Yes, it is possible, you'll need a decent pure-sine inverter to kid the grid-tie into starting up.

Google "AC coupled solar inverter".

[Gary A]

Thanks Crossy. Since I don't have the proper permits to to feed the grid, this will keep me legal.

Yep, it works. My cheap pure sine wave inverter must be OK. The green lights are happily blinking. No sparks or anything.

[George Harmony]

For the pool experts:

Is this also marketing to convince dummies like me for a good wet dream??

Flow Range: 60-140 GPM (225-530 LPM)

Head Range: 10-70 Ft. (3-21 Mt.)

DC Voltage Range: 120-180

Controller: PCC 180-BLS-M2

Discharge Size: 2" or 2 1/2" NPT

Suction Size: 2" or 2 1/2" NPT

Certification: ETL Listed

Product Details

Sun Pumps SCP series solar powered centrifugal pool pumps with brushless DC motors are the ultimate in performance and reliability. There are two types to choose from, the BC series with a 2 outlet and the BV, or "High Volume" series with a 2 ½ outlet, designed for large pools. SCP series solar pool pumps will replace almost any AC powered pool pump up to 3 HP and because they get their power from the sun, you will never have an electric bill.

https://www.sunpumps.com/Products/SCP%20100-60-180%20BV

[Naam]

For the pool experts:

Is this also marketing to convince dummies like me for a good wet dream??

your assumption seems to correct because no power consumption is mentioned.

but perhaps you solar boys measure consumption in volts, kgs of green beans, hectoliter diesel or beer and keep this a secret? enlighten me please.

Edited April 24, 2016 by Naam

[Muhendis]

OK Naam I know this is going to be a challenge for you but take a look at the top .pdf file in their list of specifications. Second thoughts here it is SCP-100-60-180-BV-Pump-Curve.pdf

The numbers are a bit confusing but everything is there. It would seem that to get the maximum flow you need to apply 180 volts at a power of 2.666 kW. So less power = less flow.

I don't know what the flow requirements are but I expect the number of solar panels needed to produce it is going to be quite significant.

[ding]

Tesla Energy

Power Wall

[Gary A]

For the pool experts:

Is this also marketing to convince dummies like me for a good wet dream??

your assumption seems to correct because no power consumption is mentioned.

but perhaps you solar boys measure consumption in volts, kgs of green beans, hectoliter diesel or beer and keep this a secret? enlighten me please.

Actually we measure in volts and amps normally converted to watts. The technology today allows brush-less DC motors to run on about any combination of volts and amps. When there is sunshine the motor runs and when it gets dark the motor stops. No electric bill, no charge controller, no inverter and no batteries. That's the simple explanation. Of course the panels have to match the size of the pump.

[Gary A]

Available from ABO trading Thailand;

LORENTZ PS Swimming Pool Pumps are high
quality products designed for use in residential and commercial swimming pools and spas. In most pool applications all of the filtration needs can be met directly from solar panels meaning no electricity costs and significant benefits to the environment. The LORENTZ pump uses a DC brushless motor for high efficiency and reliability, it is connected to a solar generator via a controller.
The controller monitors the system, controls the pump speed and optimizes the amount of water pumped based on the power available.

Benefits

• Zero energy costs provide a very fast return on investment
• Longer life expectancy than standard AC motors
• Quiet and efficient
• Proven in service record
• Speed controllable to match the pool size exactly
• Smart modular design for simple and cost effective servicing and repair
• Fast and simple installation, direct replacement for an existing pool pump

Features

• Engineered in Germany
• EC DRIVE DC brushless motors, designed for solar with over 90% efficiency
• High quality non corrodible materials used throughout
• Solar direct connect with AC connection options
• MPPT technology to maximise power use from PV modules
• Optional data logger

[Muhendis]

Off topic............can anyone tell me where I can get a motorised satellite dish receiver in Thailand?

[Muhendis]

Available from ABO trading Thailand;

LORENTZ PS Swimming Pool Pumps are high

quality products designed for use in residential and commercial swimming pools and spas. In most pool applications all of the filtration needs can be met directly from solar panels meaning no electricity costs and significant benefits to the environment. The LORENTZ pump uses a DC brushless motor for high efficiency and reliability, it is connected to a solar generator via a controller.

The controller monitors the system, controls the pump speed and optimizes the amount of water pumped based on the power available.

Benefits

• Zero energy costs provide a very fast return on investment
• Longer life expectancy than standard AC motors
• Quiet and efficient
• Proven in service record
• Speed controllable to match the pool size exactly
• Smart modular design for simple and cost effective servicing and repair
• Fast and simple installation, direct replacement for an existing pool pump

Features

• Engineered in Germany
• EC DRIVE DC brushless motors, designed for solar with over 90% efficiency
• High quality non corrodible materials used throughout
• Solar direct connect with AC connection options
• MPPT technology to maximise power use from PV modules
• Optional data logger

Engineered in Germany

That'll please Naam but where is it produced?

The sales blurb looks good. Almost makes me wish I had a pool....

[George Harmony]

I don't know what the flow requirements are but I expect the number of solar panels needed to produce it is going to be quite significant.

In the past few days ive been reading and watching vids of realistic solar setups with regard to pools and , if you want to achieve a reasonable flow with a quality brushless pump, you need indeed a lot of panels.

Perhaps i buy each month a panel and i see you back here after 2 years for the presentation of my pool hehehe pfffffff ??????

Edited April 24, 2016 by George Harmony

[Naam]

OK Naam I know this is going to be a challenge for you but take a look at the top .pdf file in their list of specifications. Second thoughts here it is SCP-100-60-180-BV-Pump-Curve.pdf

The numbers are a bit confusing but everything is there. It would seem that to get the maximum flow you need to apply 180 volts at a power of 2.666 kW. So less power = less flow.

I don't know what the flow requirements are but I expect the number of solar panels needed to produce it is going to be quite significant.

i'd call it bullshitting and supporting some peoples wet dreams not stating watts or amps. not everybody knows how to convert "solar volts" into internationally used power consumption.

and we just learned that this applies even to our solar boy @number1

just for information sake... how many m² solar panels does one need for an output of 2.6 kW?

[Naam]

SCP series solar pool pumps will replace almost any AC powered pool pump up to 3 HP and because they get their power from the sun, you will never have an electric bill.

but no worries! you will compensated by shelling out huge initial capital cost to filter and sanitise your pool

a small disadvantage is that you need an additional football field full of panels to power your home if you want to enjoy the fact never having an electric bill again

[IMHO]

just for information sake... how many m² solar panels does one need for an output of 2.6 kW?

That depends - are you talking about 2.6kW actually achieved, or are you talking about outputs based on STC/NOCT specs which you will never achieve in Thailand's heat and dust?

Edited April 24, 2016 by IMHO

[Muhendis]

Number of panels required is less than I thought. On the back of each panel there should be a rating plate/label which will tell you the peak voltage at peak current of the panel.

Assuming each panel to be 34.4volts at 5.2 Amps at peak power. A string of 5 panels in series would give 172 Volts at 5.2 Amps so three parallel strings would give the power required at peak power (a total of 15 panels). Size of the individual panels is 1.67 x 0.67 metres so the total area for 15 panels is 16.78 sq Metres.

It is quite likely that the available panels will be different from the example I have given but you should be able to calculate the number required by applying some simple maths.

Please note:- You can't just connect the three strings of panels together without a protection diode in series with each string. The reason for this is because if for some reason the voltage of one string went down (shade, bird "stinky stinky" or whatever) then the remaining strings of panels would present a high enough voltage to make a spectacular show of destruction of the shaded string.

[IMHO]

Number of panels required is less than I thought. On the back of each panel there should be a rating plate/label which will tell you the peak voltage at peak current of the panel.

Assuming each panel to be 34.4volts at 5.2 Amps at peak power. A string of 5 panels in series would give 172 Volts at 5.2 Amps so three parallel strings would give the power required at peak power (a total of 15 panels). Size of the individual panels is 1.67 x 0.67 metres so the total area for 15 panels is 16.78 sq Metres.

It is quite likely that the available panels will be different from the example I have given but you should be able to calculate the number required by applying some simple maths.

Please note:- You can't just connect the three strings of panels together without a protection diode in series with each string. The reason for this is because if for some reason the voltage of one string went down (shade, bird "stinky stinky" or whatever) then the remaining strings of panels would present a high enough voltage to make a spectacular show of destruction of the shaded string.

The specs you are working on are going to be either STC or NOCT lab specs both of which are based on low ambient temps (20-25c) and a brief flash of light between 800 - 1000W/m2. In Thailand you're not getting anything like that performance with up to 40c ambient temps, cell temps regularly in the 60c range, and up to ~1700W/m2.

Time to start looking at the temperature coefficient specs too?

[Muhendis]

Number of panels required is less than I thought. On the back of each panel there should be a rating plate/label which will tell you the peak voltage at peak current of the panel.

Assuming each panel to be 34.4volts at 5.2 Amps at peak power. A string of 5 panels in series would give 172 Volts at 5.2 Amps so three parallel strings would give the power required at peak power (a total of 15 panels). Size of the individual panels is 1.67 x 0.67 metres so the total area for 15 panels is 16.78 sq Metres.

It is quite likely that the available panels will be different from the example I have given but you should be able to calculate the number required by applying some simple maths.

Please note:- You can't just connect the three strings of panels together without a protection diode in series with each string. The reason for this is because if for some reason the voltage of one string went down (shade, bird "stinky stinky" or whatever) then the remaining strings of panels would present a high enough voltage to make a spectacular show of destruction of the shaded string.

The specs you are working on are going to be either STC or NOCT lab specs both of which are based on low ambient temps (20-25c) and a brief flash of light between 800 - 1000W/m2. In Thailand you're not getting anything like that performance with up to 40c ambient temps, cell temps regularly in the 60c range, and up to ~1700W/m2.

Time to start looking at the temperature coefficient specs too?

The panels I have used in the example are the same as I have in my installation. At the high point in the day each is producing around 176 watts. Using the information on the rating labels they should be producing 179 Watts. So it seems that my losses including diode drop, thermal, cable/termination and dust amount to 3Watts (that's 1.67%). Not significant enough to worry about.

One small point to note is that my panels are rated at 200Watts which is misleading because the peak voltage and current is the figure of merit not the maximum possible voltage and maximum current.

Edited April 25, 2016 by Muhendis

[Naam]

total area for 15 panels is 16.78 sq Metres.

not bad i admit!

[Muhendis]

total area for 15 panels is 16.78 sq Metres.

not bad i admit!

Mount them on a frame 3Metres above ground an park your car in the shade underneath.

[Crossy]

total area for 15 panels is 16.78 sq Metres.

not bad i admit!

Mount them on a frame 3Metres above ground an park your car in the shade underneath.

That is exactly what we are doing

Car port was built with putting panels on top in mind.

[Gary A]

If I were going to go totally solar, I would definitely set up a ground mount system. Orientation would be precise and cleaning the panels would be easy. At this point my panels on the roof look like they haven't been cleaned for years. It's unbelievable how dirty they get. I'm getting about half of the rated wattage. Fortunately that's enough power for my requirements even on overcast days. I doubt that my system will ever pay for itself but there is the satisfaction of having clean power free from spikes and low voltage. The best part is there are never power outages.

Maybe the question is why don't I clean them? The answer is that at 71 years old, I don't want to be standing on the roof, cracking tiles and risking injury or death. When I ask my 100 pound light weight wife to clean them, she just gives me that, "Are you crazy" look. And no, just spraying water on them doesn't work.