Living offgrid with small solar system(s)

[KonaRain]

Lots of full sine wave inverters on google etc.
I have modified sine wave.. $45 for 500 watts.a full sine wave might cost $75 for 500 watts.. 1000 watts maybe 4000 baht+.
Definitely worthwhile..
Alohs, Gents..

[KonaRain]

(I've not been following this thread, so my apologies if this product has been discussed.  The size of the thread is too intimidating to try to go back and read it from the beginning.)
 
This showed up in my Facebook feed today:  SmartFlower.  It looks intriguing, but the big question I have is how much it might cost.  I could imagine a high-rise office or condo rooftop with a "garden" of SmartFlowers tracking the sun.  They also have a FAQ with more information.
 
The Austrian company seems to have geared its info toward the Euro market, addressing such things as sub-zero temps, frost and snow.  Would it be any less appropriate/effective in Thailand's tropical climate?
 
Is this a realistic product, or just a gimmicky "feel good, look nice" product?

Smartflower looks cute, which to me means expensive..my cousin started solar in Hawaii..
I never got any, but now it's less than $1 per watt.
My neighbor has 64 solar panels to hopefully produce 13K watts. 240 watt panels are $225- 300 per panel depending on made in u.s. or china.. he said I can pay $1 per watt including da mounting brackets.. no leaks, cost extra!
Alohz

[KonaRain]

(I've not been following this thread, so my apologies if this product has been discussed.  The size of the thread is too intimidating to try to go back and read it from the beginning.)
 
This showed up in my Facebook feed today:  SmartFlower.  It looks intriguing, but the big question I have is how much it might cost.  I could imagine a high-rise office or condo rooftop with a "garden" of SmartFlowers tracking the sun.  They also have a FAQ with more information.
 
The Austrian company seems to have geared its info toward the Euro market, addressing such things as sub-zero temps, frost and snow.  Would it be any less appropriate/effective in Thailand's tropical climate?
 
Is this a realistic product, or just a gimmicky "feel good, look nice" product?

https://www.pv-magazine.com/2016/07/13/intersolar-north-america-smartflower-unfurls-its-dual-axis-tracker_100025392/
There You go.. not bad, $20k for 20,000 watts or so..tracking the Sun efficiently..
Thanks! Aloha!!

[Jing Joe]

On 20/02/2017 at 10:01 AM, KonaRain said:

Smartflower looks cute, which to me means expensive..my cousin started solar in Hawaii..
I never got any, but now it's less than $1 per watt.
My neighbor has 64 solar panels to hopefully produce 13K watts. 240 watt panels are $225- 300 per panel depending on made in u.s. or china.. he said I can pay $1 per watt including da mounting brackets.. no leaks, cost extra!
Alohz

I haven't looked at tracking systems but still reckon KISS. Keep it simple.  Being able to buy 250W second hand near-new panels at 24 cents a watt (AUD) there's no way I would track. With an excess of panels and mounted almost flat (even at 23 deg South) there's  collection during  overcast or even rain because the direction of radiation is straight down so I'm aiming at max collection on minimum days.        Previous posts re this.   

Re mounts for panels, the you-beaut aluminium gear is soooo expensive. Making your own from 25 x 25 Gal RHS is much cheaper provided any welds and holes are zinc coated from spray can.

[Muhendis]

Hi Jingjoe. Spot on with your KISS. The more bit you have the more likely and expensive will be the failures. That sun flower looks a bit of a gimmick to me. Sure it will give power as it tracks the sun but like you say. Is it really worth it? I note the stress/emphasis on the wind effects and have to wonder at the complexity of dealing with something that neither you nor I have any problem with.

[Jing Joe]

23 hours ago, Muhendis said:

Hi Jingjoe. Spot on with your KISS. The more bit you have the more likely and expensive will be the failures. That sun flower looks a bit of a gimmick to me. Sure it will give power as it tracks the sun but like you say. Is it really worth it? I note the stress/emphasis on the wind effects and have to wonder at the complexity of dealing with something that neither you nor I have any problem with.

Yes M.  Couldn't see any gimmicky picture, was enough just to read the costs and supposed advantages. Buying more panels instead would facilitate;- quicker battery recovery next morning ideally with good sun, but at least some recovery in overcast and light rains. There's 18 more 250W panels going up soon here at $60 each = 36 total and hope to eliminate any power concerns and will have NO moving parts nor wind stress/emphasis.   BTW ATM  I'm noticing less collection with certain combinations of rain & clouds.  BUT would there be any input from tracking arrays on bad days?    Anything extra to get more collection here would be a more permanent fine cooling recovery water spray than the 15 metre experimental lawn soaker hose, even then that's mostly only "interesting" or 'possibly applicable" in hot weather ATM.         KISS>> Shopping around for s/h good panels, plus extra numbers = good long term investment etc etc. To not KIS invites Murphy's law and it will break down just when you don't want,  which in reality is never??? Just saying. 

[Muhendis]

2 minutes ago, Arjen said:

KISS: Keep It Simple, and then the last S??

 

 

Stupid

[Jing Joe]

On 2/24/2017 at 0:22 AM, Arjen said:

Ok, makes a lot clear!!

 

Sorry Arjen, Spelling might be ok for the usual word  "kiss" but I avoid the  word stupid at the end. 

I smiled at your puzzlement because I thought everyone knows the last word.  

Happy Monday to you all.  

Hope George the starter of this topic returns with results of his great experiments to help small time village projects.  He has a good heart to help.

[Muhendis]

I have recently purchased a commercial desulphator to try and lengthen the lifespan of my FLA's. At the moment I am running some tests on a few VRLA batteries just to see if there is any truth in the claims. After a few days I have noticed an improvement in the battery conductance which has gone down from a very high 50 milli Ohms to 10 milli Ohms. Its early days yet so I'll see how it goes and keep you informed. 

Normal desulphation is a process of controlled over charging whilst ensuring the battery temperature does not become too elevated. This process also causes accelerated aging of the battery plates. The device I have is a pulsing desulphator which does the same thing but with short duration pulses thus ensuring no thermal problems but, depending on the degree of the problem, it could take weeks to desulphate the battery under treatment.

Here is a picture of the device I bought. Notice it takes its' power from the battery to which it is connected. Because of this it is advisable to keep the battery on trickle charge during treatment. 

 

[KonaRain]

Vanadium batteries: just build a tank? Fill with..
I forgot, will be back..
(to not k.i.s.s. is to invite Murphy to the party), right?
Aloha

[Jing Joe]

On 3/6/2017 at 11:36 AM, Muhendis said:

I have recently purchased a commercial desulphator to try and lengthen the lifespan of my FLA's. At the moment I am running some tests on a few VRLA batteries just to see if there is any truth in the claims. After a few days I have noticed an improvement in the battery conductance which has gone down from a very high 50 milli Ohms to 10 milli Ohms. Its early days yet so I'll see how it goes and keep you informed. 

Normal desulphation is a process of controlled over charging whilst ensuring the battery temperature does not become too elevated. This process also causes accelerated aging of the battery plates. The device I have is a pulsing desulphator which does the same thing but with short duration pulses thus ensuring no thermal problems but, depending on the degree of the problem, it could take weeks to desulphate the battery under treatment.

Here is a picture of the device I bought. Notice it takes its' power from the battery to which it is connected. Because of this it is advisable to keep the battery on trickle charge during treatment. 

 

Hi M. its way too early to see much but good luck.

Not clear;-  the model, or specs, or your AH capacity, and voltage of batteries.

 

I made a heavy duty one for my 48V  1000 Ah batteries some years ago but either i was too impatient or it didn't work.

they were 10 or 12 years old.

I bought AGM replacements instead.

Again; all the best and we hope to hear more results.

I liked koinas take on KISS and Murphy.  :-)

Edited March 14, 2017 by Jing Joe

[Muhendis]

As promised here are the results of my tests on the desulfator. Firstly the spec. is as in the picture. The device detects the battery voltage and adjusts itself accordingly. I connected it to a battery of four 12v 200 ahr units connected in series. I also connected a dc supply to give some trickle charging to overcome the losses caused by the desulfator. SG at the start was 1.195 which was way too low and this was a "fully charged battery" according to a three stage charger. The three stage charger works by monitoring the current in the second, absorption stage and when the current has dropped to a predetermined level the charger will switch to float charge. What is happening in the case of the batteries in test is the lead sulphate crystals have reduced the available current flow so the charger thinks that the battery is fully charged before time. 

I set the power supply to a float voltage of 54v and left the desulfation test to run for 6 hrs. The SG had changed to 1.20 in this time. I let the test run for a further 14hrs and checked the SG at 1.22. Keeping this up for a few days the SG stuck at 1.25 so I increased the float voltage of the power supply by 100mV. The SG continue to rise. This pattern of events continued until the float voltage had been adjusted to 55v and the SG had risen to 1.27. At this point I put the battery into service and the subjective observation was a satisfying improvement in capacity. I did not make any scientifically controlled tests nor was my equipment recently calibrated so the conclusion can be no better than "yes this method of desulfation seems to work". Further improvements would be to decouple the dc power supply from the desulfator with a goodly sized common mode choke. This would ensure that all the power in the pulses of the desulfator went into the batteries rather than some losses caused by the power supply output filter. That's for my next bout of enthusiasm.

[JimShortz]

On 2/23/2017 at 7:34 PM, Muhendis said:

 

Stupid

Silly is another alternative

[tlock]

I'm about to build a house, and plan to eventually go solar.  I'm very much a fan of KISS (Jing Joe do you lift?), and don't want to overwhelm the builders with specs as we are building the house.  Is solar easy enough to add a few years after the house is built?  Are there any steps I could include in the building plans now that will make things easier when we add it later?

[Muhendis]

4 hours ago, tlock said:

I'm about to build a house, and plan to eventually go solar.  I'm very much a fan of KISS (Jing Joe do you lift?), and don't want to overwhelm the builders with specs as we are building the house.  Is solar easy enough to add a few years after the house is built?  Are there any steps I could include in the building plans now that will make things easier when we add it later?

It's always a good idea to have the panels mounted so that you can effortlessly clean them and replace any that show up faulty later. As far as the angle of tilt is concerned, this will depend on your geographical location so I would recommend that you take a look at this web site which will save me a whole load of key bashing and at the same time give you enough information to cover all eventualities. http://www.solarpaneltilt.com/ What you could do is have the builders construct a nice big car port with a flat roof which is strong enough to take the weight of the panels (concrete is nice for this) and big enough for your panels and for you to walk around them. Also the location of the car port needs to be on the sunny side of the house and orientated with the long side either due north or due south depending on which hemisphere it's in. If you are planning on batteries then a separate (well ventilated for flooded lead acid) battery room would be good and also another room for the inverter(s) which can be pretty noisy with fan cooling. It might be a good idea to have a separate shed/cabin away from the house for all of this but that would depend on available space and planning regs. My battery room is 2 metres by 1 metre which is plenty big enough. The inverters are in an adjacent box on the outside of this. It's as well to remember to make provision for cable runs otherwise you will have to fiddle around with drilling holes and adding surface trunking later. PM me if you would like to see detailed drawings/pictures of my setup

 

Have fun

[Muhendis]

Absolutely Arjen, although it might not be necessary to tell the builders what is planned for the solar installation, provision could be made for a well (inexhaustible supply of cold water) maybe or a plumbing system to include cooling the panels. By the way your figure of 15% is very conservative. With an ambient of 35 deg C the real life loss in performance can be as much as 25%. Panels are characterised at an ambient of 25 deg C. and will lose 0.46% power per degree C dependant on panel construction. That is the official figure under controlled conditions. The reality is dependant on many other factors. You should look at this site.  http://pveducation.org/pvcdrom/modules/nominal-operating-cell-temperature and other places for more information. Jingjoe has already tried the water cooled method and has mentioned it's success before. That's now on my todo list.

[SOUTHERNSTAR]

Hi everyone, I need some advice. I am a starter on this subject, please be slow and gentle. We are buying a property that will be off the grid. 

 

According to hydrological studies we will need a borehole of +- 100 m deep, which would require about a 2,2 kw pump (looking at a stainless Franklin don't know if correct ??) to lift the water into raised tanks (to avoid having to pump a second time). There will also a dam which will serve as a backup for irrigation water and we will need about a 1,5 kw pump to lift water from the dam to the highest point.

 

At present we consume on average 33kwh per day. This however includes a swimming pool motor that works about 5 hours a day and a borehole pump that works about 30 minutes per day. My estimate is that the house excluding the swimming pool and borehole consume between 15 and 20 kwh per day. The new place will not have a swimming pool and by designing the house correctly we should be able to cut back on electricity needed for AC's (nice breeze on top of the mountain). We also bought a wood burning stove which we can use for heat in winter and for cooking, this should bring down our electricity consumption further.

 

The options available with my limited knowledge is as follows (all options will have batteries to store energy):

1. Install a 10 kw solar system with a 5 KW diesel generator as backup.

2. Install a 5 kw solar system and a 5 kw wind turbine system with a 5 kw diesel as backup. Each system with battery storage.

3. Install a 10 kw solar system with a wind turbine(s) as backup.

 

I have many questions but let me limited to these ones:

1. How many batteries will I need on the pure solar system to survive 2 days without sun ? Which batteries are the best deep cycle or gel batteries (confusing) ?

2. If we go for a split solar/wind system can we use solar to charge the wind systems batteries when there is no wind and the other way around ?

3. If we use option 3 can we use more smaller wind turbines, say 2 kw instead of one big one. As the wind turbine will be a backup I don't want to rely on only 1 turbine. Do we need a 10 kw turbine or can we get away with a 5 kw turbine ?

 

We will be planting trees and crops that we need irrigation and without electricity there will be no irrigation, thus all the backup systems. We will use drip irrigation to cut down water and electricity consumption. At the start we will use about 200 000 litres per week but this will increase over 5 years to  750 000 litres per week. This increase in water consumption could see us facing an electricity shortage. We need a system that can be expanded if need be.

 

Advice please.

 

 

 

[Muhendis]

Hi Southernstar. Firstly the borehole. This type of well is drilled way down to get water from below an impermeable layer. The water will be under pressure to get to the surface. I have one which is 51 metres deep but the water is pushed up to around three metres from the top of the hole. It is an Artesian well http://www.yourdictionary.com/artesian-well. If your borehole is suitably sited then you may not require such a powerful pump as your 2.2Kw job also this type of pump will be way down in the hole and expensive to retrieve should anything go wrong. I was recommended to use one also but instead I use a 250w pressure pump and a venturi which is located 12 metres down the hole. I'm pumping water 300 metres horizontally + 3 metres vertically into a 2,000 litre storage tank which takes roughly 45 mins to fill. Best thing to do is to drill your bore hole first and see how high the water rises before buying the pump.

 

Batteries. To determine how many batteries you will need take a good look at this https://www.altestore.com/howto/how-to-size-a-deep-cycle-battery-bank-a94/

 

As for the best type of battery deep cycle is the type you need but the chemistry of them is dependant on cost and performance. Lead acid comes in several different flavours. Flooded, maintenance free and gel. Flooded is the cheapest but needs a bit of maintenance to keep them in good condition. Maintenance free is what it says but more expensive. Gel is the most costly and requires least attention. The lead acid chemistry has a shorter life in elevated temperatures. All lead acid batteries suffer from sulphation which is caused by partial charging (as in solar when the sun don't shine all day). It can be got round by using a charger with a desulfation cycle. LiFePO4 (lithium iron phosphate) is a better choice but very expensive and needs some electronics in the form of a battery management system to ensure best performance. LiFePO4 batteries will have a better life expectancy and can be cycled deeper than lead acid. They are also smaller and lighter for the same power density. Battery life is determined by the number of cycles and the depth of discharge LiFePO4 is the most cost effective solution over the life of the system which could well be in excess of 20 years. After that time your solar panels will still be giving 80% of their original power when first installed. There are other flow technology "batteries" which could be used but there are cost and performance issues for small scale home power storage.

 

The number of solar panels you need depends on the number and type of batteries you need. The batteries need to have their charge restored in around 4.5 hours each day.

 

Charge controler. This sits between the inverter and the power source and can be a hybrid which will take inputs from wind, solar and your diesel generator. A lot of inverters have them as part of the inverter. The size of the inverter must be enough to power all loads worst case conditions. Don't forget that startup current for a motor starting under full load conditions can be as much as 9 times the normal running current. Most inverters are able to supply double the maximum rated output for a few seconds so for example, a pump that requires a starting current of 10 amps and a running current of 1.2 amps would need an inverter with a 5 amp capability and a 100% overload capability for a few seconds.

 

Have you considered having your house system separate from your farm/pump system?

 

[SOUTHERNSTAR]

Muhendis

 

Thanks for the info. Yes I am considering two systems, maybe 2x5kw systems. The house will be fine on a 5kw and the farm system even with big pumps should be okay with 5 kw if I don't start all the pumps at once.

Edited May 2, 2017 by SOUTHERNSTAR

[Crossy]

@SOUTHERNSTAR are you going off-grid because you want to or because it's not possible to get grid power in your location?

 

Solar, particularly stand-alone, is still very expensive, and the systems you are considering are certainly larger than "small". It's worth investigating just how much it would cost to get "real" power and do some ROI calculations.

 

[SOUTHERNSTAR]

55 minutes ago, Crossy said:

@SOUTHERNSTAR are you going off-grid because you want to or because it's not possible to get grid power in your location?

 

Solar, particularly stand-alone, is still very expensive, and the systems you are considering are certainly larger than "small". It's worth investigating just how much it would cost to get "real" power and do some ROI calculations.

 

Crossby the cost to bring grid power in will be about the same as to buy a solar system. We have to bring in power over 5 km away. At present my CIF Bangkok price for a 10 kw solar system from China starts at $ 8 000 and for a 5 kw solar and 5 kw wind is $ 12 000. It seems as if solar panels is duty free, but I will speak to Thai customs before ordering. I have a guy that has done our present house's wiring and he is very good. He will do the installation for us as part as the wiring of the new house. He does solar in farming areas around here. Due to the long distance to bring in grid power the ROI will be very short. The other factor is the reliability of the grid power and the effect of bush fires will have on our supply. 

[Muhendis]

Please be aware that what you get from China may be of variable quality. I have found that 200ah batteries can be 10% lighter in weight than better qualified ones (made in Thailand). Solar panels may have cells which are not so well bonded and will shatter the front glass after a few months due to thermal stress. The design of inverters is, for some companies, questionable. If your kit comes from a reputable manufacturer who is involved with a European company for instance then they will have a QA system in place which will assure a better product, and the price to go with it. I cannot emphasise enough the need to carefully check the specs. looking as much for what is missing as for what is there.

Importing solar batteries into Thailand attracts a 10% duty. Electronics and solar panels are I beleive, duty free. For more information check out this.

http://en.customs.go.th/cont_strc_simple.php?lang=en&top_menu=&current_id=14223132414b505e4e 

If you are going to use an agent then that will add significantly to the overall cost but is likely to offer door to door service.

[SOUTHERNSTAR]

On 2017-5-2 at 9:07 PM, Muhendis said:

Please be aware that what you get from China may be of variable quality. I have found that 200ah batteries can be 10% lighter in weight than better qualified ones (made in Thailand). Solar panels may have cells which are not so well bonded and will shatter the front glass after a few months due to thermal stress. The design of inverters is, for some companies, questionable. If your kit comes from a reputable manufacturer who is involved with a European company for instance then they will have a QA system in place which will assure a better product, and the price to go with it. I cannot emphasise enough the need to carefully check the specs. looking as much for what is missing as for what is there.

Importing solar batteries into Thailand attracts a 10% duty. Electronics and solar panels are I beleive, duty free. For more information check out this.

http://en.customs.go.th/cont_strc_simple.php?lang=en&top_menu=&current_id=14223132414b505e4e 

If you are going to use an agent then that will add significantly to the overall cost but is likely to offer door to door service.

I agree with you. The companies I am working with on the solar side is delivering systems world wide with QA systems inplace.  Some of these companies are prepared to stand in for shipment cost and customs if their products break within the warrantee period. The wind turbines will be sourced from a German company. I decided on a system of smaller 2 kw turbines. They are easier to work with and the poles are much smaller. When you go to 5kw turbines you need 8 to 12 m hydraulic poles at $ 3000 while the 2 kw ones can be made locally. 

[George Harmony]

Hi there all, here I am again and sorry for being absent so long. I promised you all before to report about my experiments with water batteries. I did some experiments and i was able to burn some leds with or without joule thief the whole night long.

About a detailed report i think this guy is better in reporting his findings: http://www.aaronparsekian.com/?cat=10

 

Now im experimenting on (active) solar distillers. Anyone amongst you have experience with diy solar stills??

my intention is making drinking water so i dont have to buy or boil with gas.

Edited July 13, 2017 by George Harmony

[George Harmony]

Just a weird idea of mine when i saw this example on internet:
How about if you make these solar distillers as a canopy and fill it with ground-, sea-, or creekwater. When its raining you  can also use these (canopy)distillers as rainwater catcher, 3 in 1 ?

..

Edited July 14, 2017 by George Harmony

[George Harmony]

just want to share about this man which inspires me so much. He travels around the world with his boat and promotes low tech sustainable living.

 

http://oceans.taraexpeditions.org/en/m/environment/mankind-the-ocean-pollution/interview-corentin-de-chatelperron-nomad-of-the-seas/

[George Harmony]

i planned to buy a 12volt solder iron and then i saw some examples with cigarette lighter. Very handy if you only occasionally need to solder ?

 

i just use a concrete nail.

[George Harmony]

About offgrid living @my home:

I am convinced that with these small systems consisting of solar panels, homemade briquettes from waste and DIY small simple cheap biogas plant many houses can generate their own energy for cooking & electricity. If you can cook FREE with briquettes or biogas you also can make your own drinkwater by boiling and/or distilling.

[George Harmony]

Next step is pyrolysys plastic @home, so nearly no waste :) 

[Jing Joe]

Hi George and all the old mates.

Good to see George back again in August after long absence  (like me)  

My pumped water-panel solar hot water system is now 6 x 250W solid state solar hot water and works REALLY well. No moving parts, no leaks, no faulty Non return valve etc.

The 180Litre tank is up to 65 degrees by 11am and 12v  through the thermostat turns off the 40A Solid Stare Relay that handles the 80V at 16A  (approx) into the1500W  48V heater element that replaced the 240V never used element.

    Bypassing the thermostat it easily went to 96 degrees by 2pm.

The second hand panels were about $50 each.

Needed experiments more than just paper calculations as to the final configuration of panels and element connections. Internal  resistance rather influenced it.  More info later  if anyone wants it.              George you have my email address.

Now there are 36  panels on the roof for home power and great for the large air con.

Very likely George could easily boil water for hours on end each day in a small boiling chamber with an element and 6 panels.   You could distill quite a bit of water each day.

An automatic water feed could  maintain the level of the small volume of boiling water.

Some commercial distilled drinking water has ozone added for extra (??)   purification and this breaks down to quite oxygenated water and is delicious.

 

There's been quite a bit of bad publicity about drinking distilled water but my question is ;-  Apart from some possibly dissolved oxygen or nitrogen in rain water, whats the difference?     Cool evaporation is how nature does it and maybe if it wasn't for the distillation rain water process, wouldn't all the water on earth have become more and more polluted?

Just thinking.