Solar system for Office.

Jackal65

Jackal65

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My computer consumption :300watt/h from the plug. I need to be able to work for 14 hours a day minimum.

Other considerations is my Fibre that consumes 32watt/h hour for the ONT and Router along with 2 router UPS systems.

Total office consumption is 332watt/h.

Solar backup system will be
1X 5.5Kw/h Lithium Battery
1X 5Kw Inverter
4X 540 Watt solar panels.

My math so far is 5500watt/h - 20% (5500 - 1100) = 4400watt/h
Total power consumption is 332watt/h
Total Time 4400 / 332 = 13.2 hours leaving a 20% charge on the battery. (Excluding solar power generation.)

Will this work? What am I missing?
 
When the sun is shining you won't be touching your reserve and you'd be charging your battery and covering your requirements at the same time. Should be more than adequate I'd say.
 
Jackal46 said:
My computer consumption :300watt/h from the plug. I need to be able to work for 14 hours a day minimum.

Other considerations is my Fibre that consumes 32watt/h hour for the ONT and Router along with 2 router UPS systems.

Total office consumption is 332watt/h.

Solar backup system will be
1X 5.5Kw/h Lithium Battery
1X 5Kw Inverter
4X 540 Watt solar panels.

My math so far is 5500watt/h - 20% (5500 - 1100) = 4400watt/h
Total power consumption is 332watt/h
Total Time 4400 / 332 = 13.2 hours leaving a 20% charge on the battery. (Excluding solar power generation.)

Will this work? What am I missing?
Click to expand...

Your consumption on 330W for 14hrs is 4620wh or 4.6kWh, you have a 5.5kWh battery excluding solar.

So without going any deeper into the details, yes the system will work, with plenty of power to spare.
 
Flanders said:
When the sun is shining you won't be touching your reserve and you'd be charging your battery and covering your requirements at the same time. Should be more than adequate I'd say.
Click to expand...
Yes, over 10kWh potential capacity from solar on a good day. Will be more than adequate.
 
That will be plenty for all the lights in the house + TV and a few plugs for laptops/computers/phones/fridges etc
 
If this is for loadshedding it's overkill. You only need a 1 kW / 1kWh trolley.

Also what are you doing on your PC that it averages 300 W?
 
Tomtomtom said:
If this is for loadshedding it's overkill. You only need a 1 kW / 1kWh trolley.

Also what are you doing on your PC that it averages 300 W?
Click to expand...
He says right there that he wants 14hrs runtime out of it at a minimum, so not just loadshedding but the extended power cuts we have now and again, in that sense I don't see what is wrong with an overspecced system.
 
TheChamp said:
He says right there that he wants 14hrs runtime out of it at a minimum, so not just loadshedding but the extended power cuts we have now and again, in that sense I don't see what is wrong with an overspecced system.
Click to expand...

Then 1 kW plus a couple panels.

People are forgetting opportunity cost. What's wrong with overspecced is all the money not going into the core business to make more money.
 
We do have extended power cuts that can last for several days not just hours. Having a backup that will allow the office to run will be more cost effective then having a generator burning fuel.
 
Jackal46 said:
My computer consumption :300watt/h from the plug. I need to be able to work for 14 hours a day minimum.

Other considerations is my Fibre that consumes 32watt/h hour for the ONT and Router along with 2 router UPS systems.

Total office consumption is 332watt/h.

Solar backup system will be
1X 5.5Kw/h Lithium Battery
1X 5Kw Inverter
4X 540 Watt solar panels.

My math so far is 5500watt/h - 20% (5500 - 1100) = 4400watt/h
Total power consumption is 332watt/h
Total Time 4400 / 332 = 13.2 hours leaving a 20% charge on the battery. (Excluding solar power generation.)

Will this work? What am I missing?
Click to expand...
The only thing I see is that you might want to account for efficiency loss too, which is roughly another 10-20%. If the majority of your operating hours are during daylight hours then you should be golden. The solar during the day should be more than enough to handle the load without tapping into the battery reserve.

Adding solar panels is a smart move. Our work only installed battery backups (so no solar panels) and with the 2 week outage we are currently in the middle of the batteries got depleted after day 2 with no way to charge them back up aside from a generator which was broken. Thankfully we managed to get the generator back up and running and could charge the batteries on day 5 of the total grid outage. Had they spent the little bit extra for panels there wouldn't have been issues and we wouldn't have to run generator at all.
 
Crusader said:
The only thing I see is that you might want to account for efficiency loss too, which is roughly another 10-20%. If the majority of your operating hours are during daylight hours then you should be golden. The solar during the day should be more than enough to handle the load without tapping into the battery reserve.

Adding solar panels is a smart move. Our work only installed battery backups (so no solar panels) and with the 2 week outage we are currently in the middle of the batteries got depleted after day 2 with no way to charge them back up aside from a generator which was broken. Thankfully we managed to get the generator back up and running and could charge the batteries on day 5 of the total grid outage. Had they spent the little bit extra for panels there wouldn't have been issues and we wouldn't have to run generator at all.
Click to expand...
And panels are now very cheap, you can integrate them in any setup.
 
Jackal46 said:
Right so Assume I don't know what you all know about this stuff.

Do I connect the solar panels in parallel or series? I have provided a link to the inverter below.

Sacolar - WiFi compatible- 5KVA / 5KW Pure Sine Wave Axpert Type 48V Inverter / 100A High Voltage MPPT / Parallel

Other inverter recommendations are welcomed but I was told these are not bad.
Click to expand...
You get an installer to come and do the connections. They should know how to connect the panels for best performance within inverter specs.
 
Jackal46 said:
Right so Assume I don't know what you all know about this stuff.

Do I connect the solar panels in parallel or series? I have provided a link to the inverter below.
Click to expand...
There's a good guide in this post:

Ted Lassoes the Sun!

So I know everyone loves Hubbles because of the 1C and great price. I've asked for a quote from Power Forum Store for two of them and was checking out Solar Advice too for comparative pricing. https://solaradvice.co.za/product/hubble-5-5kwh-lithium-ion-battery...
mybroadband.co.za mybroadband.co.za

Jackal46 said:
Sacolar - WiFi compatible- 5KVA / 5KW Pure Sine Wave Axpert Type 48V Inverter / 100A High Voltage MPPT / Parallel

Other inverter recommendations are welcomed but I was told these are not bad.
Click to expand...
Axperts are steam engines. Have a look at this:
 
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