Want to upgrade current UPS setup to Solar

Assalam-o-alikum,

My current UPS setup is APC-1500SUI with 2 X 165 AGS Batteries, it is two months old and working great Allhumdulliah. I want to upgrade it to solar. so it will charge batteries on solar during the day time and if needed then charge batteries on WAPDA during night time.

My current load on UPS is mention below

3 Fans

4 Energy Savers

2 PTCL DSL Device + WIFI Router

1 Laptop

Please advice about the good solar panels and charge controller for above setup.

My current budget for expansion is 60-80K.

I live in Hyderabad but working in Karachi :).

looking forward specially from farhan_ds & Ijaz Ahmed.

Jazak Allah Khair

i few points

  • Calculate you load in WH ( what is rating of energy saver in watts ? rating of PTCL modem and DSL router.Laptops are usually ~60Watts)
  • Go for MPPT controller (even a EP-Solar MPPT can work, it's efficiency is as high as 97% )
  • Go for quality Panels e.g Canadian Solar, Sharp, LG, Trina (haven't used the last three but have heard good reputation for these)
Date	6/14/2014
Time 	10:10
Grid	On Just came back
UPS charging	Off
Weather	35C Haze 
Led Status	Solid
PV Voltage	47.9
CC Voltage	13.9
Battery Voltage	13.4
PV Current	3.9
CC Current	12.81
Load current	-0.19
Power In	186.81
Power Out	178.059
Efficiency %	95.31556127

Suppose fans are of 100w each =300watts Energy saver =30*4 =120w Modems hardly utlize 20-30watts And I think he can't run all these thing simultaneously, so his usage will be around 400-500watts/hr Now what will you suggest Yousaf

Sent from my LT22i using Tapatalk

[quote=“waqar789, post:3, topic:21211”]

Suppose fans are of 100w each =300watts Energy saver =30*4 =120w Modems hardly utlize 20-30watts And I think he can't run all these thing simultaneously, so his usage will be around 400-500watts/hr Now what will you suggest Yousaf Sent from my LT22i using Tapatalk

[/quote]

it's Watts x hours not Watts/hr.

In a Off-grid system (no input from Wapda) , you have to balance the Load in WH with Input from Solar.

For off-grid system it will be

Watts * Hours (number of hours application will be on) * 0.52(total derating for a battery based system).

For a Hybrid system it is different.

But he already have Apc UPS ( I don't whether it stops charging if you connect a external charger or not. My DESI UPS doesn't, it instead rely on the battery's SOC or Voltage for charging) So his system is more of a Hybrid system.

@tufail_74 is using a similar setup.

but if we go with the budget route his system will consist of the following

EP-solar Tracer-4215Rn which supports upto 1170W of panels @ 24V costs Rs 25k which leaves 55K

55K can buy him 687Watt of solar panels (he can add more panels later on )

Or Else he can go with a larger controller e.g

Morningstar MPPT 40A Costs Rs 50K in Pakistan (cheaper if you import it on your own)

Morningstar MPPT 60A Costs Rs 70K in Pakistan (~ $500 Online)

and buy panels for the rest with both Morningstar can support upto 6000Watts

According to their official email

[quote=", post:, topic:"]

Morningstar’s MPPT controllers can operate with an oversized array that is several times larger than the

maximum Nominal Solar PV ratings, while still limiting the maximum battery current to the controller’s

maximum current rating

[/quote]

[quote=“swsb, post:, topic:”]

Assalam-o-alikum,

My current UPS setup is APC-1500SUI with 2 X 165 AGS Batteries, it is two months old and working great Allhumdulliah. I want to upgrade it to solar. so it will charge batteries on solar during the day time and if needed then charge batteries on WAPDA during night time.

My current load on UPS is mention below

3 Fans

4 Energy Savers

2 PTCL DSL Device + WIFI Router

1 Laptop

Please advice about the good solar panels and charge controller for above setup.

My current budget for expansion is 60-80K.

I live in Hyderabad but working in Karachi :).

looking forward specially from farhan_ds & Ijaz Ahmed.

Jazak Allah Khair

[/quote]

your load is around

3 fans = 300W.

router = 30W

4 Savers = 100W

Laptop = roughly 80-90W

that would be peak consumption of around 500W.. in actuall u would be using a lot less, as laptop charges in 2 hours and then disconnect.. also fans not all time running and not always full speed.. nevertheless, you always should prepare for atleast maximum..

add 20% extra power for over head.. that would be around 600W peak power. out of which you would be able to get between 250-400W continuous in day time,

so you would essentially require around 600W of panels and a charge controller to match it..along with future needs.

since you are on a buget, you can do a lot cheaper by going for polycrystaline panels instead of mono panels.. although their efficiency is less, but they are a lot cheaper, and even future additions would be cheap, so you would be able to afford any upgrade instead of going for small incremental ones.if affordability is an issue then poly panels are the way to go..lot of saving.

but donot skimp on a charge controller or wiring.. since your needs wont be growing much, you can make do with a proepr quality 16mm DC cable ..that would be able to hold all your current load and any future load for many years.. donot go for cheap wiring.. its a one time expense which will save you a lot in future..

for your Current and POSSIBLE FUTURE NEEDS, you should invest in a bigger CC than your needs now.. you could get a 30A CC but a 40A CC would be highly advisable.. EP Solar is a reputed brand easily available and reliable and has great specs.. again if affordability is an issue you can go for a PWM CC, from EP Solar.... MPPT does have some advantages in a small sized setup as it squeezes every bit of power from the panels but when you would upgrade more panels, then PWM would be just as fine..all this depends on your buget,, both choices are only buget dependant

since you are using APC, you can use both the CC and the ups together, the APC will reduce its charging to the point that what the battery needs.. otherwise, you can add a switch in the circuit which will shut down APC all the day when solar power is coming for free and running your whole ups only on solar power..at night when solar power goes down, ups springs into action automatically and only then wapda works.

a big mistake everyone makes is that they limit their vision that this initial setup is all they will be needing.. as soon as you get that installed you would soon be greedy for more, every one does, including me.. human nature :)

Hope you have now a basic understanding of your questions answered..

[quote=“farhan_ds, post:5, topic:21211”]

your load is around

3 fans = 300W.

router = 30W

4 Savers = 100W

Laptop = roughly 80-90W

that would be peak consumption of around 500W… in actuall u would be using a lot less, as laptop charges in 2 hours and then disconnect… also fans not all time running and not always full speed… nevertheless, you always should prepare for atleast maximum…

add 20% extra power for over head… that would be around 600W peak power. out of which you would be able to get between 250-400W continuous in day time,

so you would essentially require around 600W of panels and a charge controller to match it…along with future needs.

[/quote]No, calculations are not that simple, you have have add in the system derate factor 0.52 (in case of a Off-grid system) and also need some cover for the weather…

In my 11 years of experience with Laptops, I have used all on AC Power 80% of the time… ;)

[quote=", post:, topic:"]

since you are on a buget, you can do a lot cheaper by going for polycrystaline panels instead of mono panels… although their efficiency is less, but they are a lot cheaper,

[/quote] Poly-crystalline are more tolerant to shading/clouds too.[quote=", post:, topic:"]

and even future additions would be cheap, so you would be able to afford any upgrade instead of going for small incremental ones.if affordability is an issue then poly panels are the way to go…lot of saving.

[/quote]

You can use Mono-crystalline and Polycrstalline in series if their IMP are within 10% of each other or in Parallel if their VOC iswithin 10% of each other

[quote=", post:, topic:"]

but donot skimp on a charge controller or wiring… since your needs wont be growing much, you can make do with a proepr quality 16mm DC cable …that would be able to hold all your current load and any future load for many years… donot go for cheap wiring… its a one time expense which will save you a lot in future…

for your Current and POSSIBLE FUTURE NEEDS, you should invest in a bigger CC than your needs now… you could get a 30A CC but a 40A CC would be highly advisable… EP Solar is a reputed brand easily available and reliable and has great specs… again if affordability is an issue you can go for a PWM CC, from EP Solar… MPPT does have some advantages in a small sized setup as it squeezes every bit of power from the panels but when you would upgrade more panels, then PWM would be just as fine…all this depends on your buget, both choices are only buget dependant

[/quote]

MPPT were actually designed for large system where every percentage means loses in KWH, so they work both in small and large system (PWM is just waste of money in the long run). The data I posted in my first post was taken from the a MPPT charge controller. The bigger the CC the better, or he can go with brands which have “follow me” mode so he can install further panels along with the new CC and it will be able to synchronize across the system:)

[quote=", post:, topic:"]

since you are using APC, you can use both the CC and the ups together, the APC will reduce its charging to the point that what the battery needs… otherwise, you can add a switch in the circuit which will shut down APC all the day when solar power is coming for free and running your whole ups only on solar power…at night when solar power goes down, ups springs into action automatically and only then wapda works.

[/quote]

Thanks I wanted to know how APC works with a external charger (in this case Solar panel with CC)

[quote=", post:, topic:"]

a big mistake everyone makes is that they limit their vision that this initial setup is all they will be needing… as soon as you get that installed you would soon be greedy for more, every one does, including me… human nature :)

Hope you have now a basic understanding of your questions answered…

[/quote]

Needs grows, people start to learn about their usage and systems evolve/grow.

Jazak Allah to all for replying on the topic. So far now I have to increase the budget in order to buy one time expensive Morningstar MPPT 40A with 600 Watts Mono-crystalline panels. Any other good brand of solar panel like Canadian Solar mention by yousaf465 easily availabe in Karachi? Also is the Charge Controller come with warranty too as the solar panels?

Once Again thanks a lot and Jazak Allah for sharing useful information.

The cable size mentioned by Mr. Farhan is far too much than required.

Please have a look at the link below. This will help you get the approximate correct size of the PV cable cable.

http://www.solar-wind.co.uk/cable-sizing-DC-cables.html

Remember your MPPT CC will give you option to connect three panels in series thus the current will remain as of the the one panel (8A) or so. Laying 16mm2 cable for only 8A is too extra sending while even the 6mm2 cable can go for 20A easily.

Remember this is a proper brand cable not the local/china made cheap cable. Go for FR cable or Pakistan cables.

The battery cable will surely be thicker depending on the load and future expansion.

This is always a good method to install what is needed rather than just assumption and hence waste of money.

[quote=“swsb, post:7, topic:21211”]

Jazak Allah to all for replying on the topic. So far now I have to increase the budget in order to buy one time expensive Morningstar MPPT 40A with 600 Watts Mono-crystalline panels. Any other good brand of solar panel like Canadian Solar mention by yousaf465 easily availabe in Karachi? Also is the Charge Controller come with warranty too as the solar panels?

Once Again thanks a lot and Jazak Allah for sharing useful information.

[/quote]

According to Morningstar email, Nizam solar are their official distributor in Pakistan. Usually Karachi office is well stocked (being their headquarter) and do offer better prices compared to their Lahore office (but you have to do a little bit of bargaining too ) .

Yes every major Solar Installer has offices in Karachi ( Pakistan’s economic capital), so all quality brands are available in Karachi.

Yes, Morningstar official warranty for MPPT controller is 5 years. all info for that about can be found at http://www.morningstarcorp.com/products/tristar-mppt/

Well I am using Morning-star MPPT 45A and extremely happy from it. For a solar setup, always think ahead and make a good plan. Saving few thousands now can cost you a lot in the longer run. If you are going to use MPPT CC then no need to go for a fancy powerful inverter rather just get a sine wave inverter with max power capacity you can afford now. as farhan very rightly said that you will start becoming greedy once the solar start giving you power.

[quote=“tufail_74, post:8, topic:21211”]

The cable size mentioned by Mr. Farhan is far too much than required.

Please have a look at the link below. This will help you get the approximate correct size of the PV cable cable.

http://www.solar-wind.co.uk/cable-sizing-DC-cables.html

Remember your MPPT CC will give you option to connect three panels in series thus the current will remain as of the the one panel (8A) or so. Laying 16mm2 cable for only 8A is too extra sending while even the 6mm2 cable can go for 20A easily.

[/quote]

Acceptable loss should be 3%, the voltage should be such that it doesn't exceed maximum VOC supported by the Charge controller at very lowest temperature recorded at your location.

total Voltage = (Number of Panels in a single string x VOC of a single Panels) this is case when same panels have been used in a single string. and it does drastically reduce the cable size. e.g

If you need 20m cable from Panels to Charge controller :

Panels at 12V with total 8A require 25mm2 cable

while Panels at 58V with total 8A require just 4mm² cable

Array's arrangement can be easily calculated using this string calculator http://www.morningstarcorp.com/string-calculator/ althoug some people prefer Midnite's string calculator http://www.midnitesolar.com/sizingTool/index.php

[quote=", post:, topic:"]

Remember this is a proper brand cable not the local/china made cheap cable. Go for FR cable or Pakistan cables.

The battery cable will surely be thicker depending on the load and future expansion.

This is always a good method to install what is needed rather than just assumption and hence waste of money.

[/quote]

Cable required from Charge controller to battery should be as minimum in length as possible, usually upto 3 feets is consider good.

when you wire panels in series, the current remains the same. That is why I said because of his requirement. With MPPT, you can add 3 panels as the Voc are usually 37 so in total , they go upto 112 or so.

By the way, voltage in that website is the PV volt not the battery volt so do not put 12V there. Use max Voc of your array.

You dont fix 12V panels for bigger setups. You should always go for maximum Voc to reduce current. If you install around 750watt panels, you can use 3 panels of 255watts in series in one string and off you go.

Always you have to consider everything including panels, CC inverter together to make the best setup. For example, I chose 48V system to get max power from CC. Only for this reason I got inverter of 5000VA. Now i can go upto 2000watt panels but if I had chosen 24V system then the max power would have been half and I was to be loosing that capacity of CC.

It is recommended to have shorter length from battery/inverter/CC but that is not mandatory, you can have longer cables but then you have to consider voltage drop and proper route as there be heat generation because of high current.

[quote=“tufail_74, post:12, topic:21211”]

when you wire panels in series, the current remains the same. That is why I said because of his requirement. With MPPT, you can add 3 panels as the Voc are usually 37 so in total , they go upto 112 or so.

By the way, voltage in that website is the PV volt not the battery volt so do not put 12V there. Use max Voc of your array.

[/quote]

That 12v and 58V and keeping current at 8A equations were for example only, 12V panels don't exist ( you can't charge a 12V battery with 12V VOC panels ;) )

Current adds up in Parallel and Voltage adds up in Series :)

[quote=", post:, topic:"]

You dont fix 12V panels for bigger setups. You should always go for maximum Voc to reduce current. If you install around 750watt panels, you can use 3 panels of 255watts in series in one string and off you go.

[/quote]

Yes, I do agree with that, you should go for the maxmium VoC possible taking into account the VOC supported by your CC.

For panels you can easily calculate the number of strings and number of panels required, for model of panel which is avaiable using morningstar string calculator. For a ~750W, 3 X 250W or 3 x 255W in series is a optimum configuration.

[quote=", post:, topic:"]

Always you have to consider everything including panels, CC inverter together to make the best setup. For example, I chose 48V system to get max power from CC. Only for this reason I got inverter of 5000VA. Now i can go upto 2000watt panels but if I had chosen 24V system then the max power would have been half and I was to be loosing that capacity of CC.

It is recommended to have shorter length from battery/inverter/CC but that is not mandatory, you can have longer cables but then you have to consider voltage drop and proper route as there be heat generation because of high current.

[/quote]

Higher voltage setups are more efficient, some people say,

24V system is 200% more efficient compared to 12V system

48V system is 400% more efficient compared to 12V system

reason being :

P=I2R and Increased current causes increased heat losses. :)

His System is 24V (2 batteries) and Location being Hyderabad
So the figures required will be

Min battery Voltage: 23.0V
Maximum Battery Voltage: 31V
Lowest ever recorded temperature: 6.1 C
Average High temperature: 40 C

Morningstar Tristar MPPT 45A

Module used is Canadian Solar - CS6P-255M

PV Module Specifications
Module Name	Canadian Solar - CS6P-255M	
Pmax	255.00	W
Voc	37.70	V
Isc	8.74	A
Vmp	30.50	V
Imp	8.35	A
Voc coefficient	-0.336	%V/°C
NOCT	45.0	°C
Module Operation
Min. Voc	32.64	V
Max. Operating Voc	35.46	V
Max. Voc	38.62	V
Min. Vmp	25.44	V
Max. Vmp	28.26	V

It will calculate the following

http://www.morningstarcorp.com/string-calculator/#manufacturer=89&module=7514&product=24&vmin=23&vmax=31&tmin=17.7&tmax=40&tminunits=c&tmaxunits=c