Inverter (power?) | recommendations for the ignorant

Creag

Creag

The Boar's Rock
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Unfortunately this is becoming an important consideration for people working from home. To a lesser extent, also for those of us who get shafted by load shedding from 18h00 onwards.

(In my area/block, it's 4x a week (Tue, Thu, Sat & Sun) from 18h00 to 22h00.)

I am considering getting an inverter but have no idea what to look for or the pros and cons. For me it would be to run the TV, Explora, a light and computer for 3 to 4 hours at most. If it were affordable, I would probably get something that would last longer.

(Cooking is not a consideration, as I can cook with gas.)

Then there are those who work from home and need to run a laptop, printer, modem and perhaps a light for 3 to 4 hours.

What would you recommend as a suitable inverter(s) for home and home/office use?

It would be really nice if you could leave a link here if you find something worthwhile.

Thanks in advance.
 
For a sensitive electronics like a PC you should use a sine wave inverter. For lights etc you can use a square wave inverter. Sine wave is much more expensive than square wave though.
 
envo said:
inverter as in for solar power?
Click to expand...

Converts 12 V DC to 220 V AC.

I have this 200 W sine wave inverter I bought 10 years ago. Was R2,000 back then.

fwkrzvvh.jpg
 
McT said:
Unfortunately this is becoming an important consideration for people working from home. To a lesser extent, also for those of us who get shafted by load shedding from 18h00 onwards.

(In my area/block, it's 4x a week (Tue, Thu, Sat & Sun) from 18h00 to 22h00.)

I am considering getting an inverter but have no idea what to look for or the pros and cons. For me it would be to run the TV, Explora, a light and computer for 3 to 4 hours at most. If it were affordable, I would probably get something that would last longer.

(Cooking is not a consideration, as I can cook with gas.)

Then there are those who work from home and need to run a laptop, printer, modem and perhaps a light for 3 to 4 hours.

What would you recommend as a suitable inverter(s) for home and home/office use?

It would be really nice if you could leave a link here if you find something worthwhile.

Thanks in advance.
Click to expand...

You read my mind, i've been thinking about getting the same, but every time i go looking for inverters and batteries the amount of options available makes the process kinda daunting.

We need specifics people. :)
 
Zyzzyva said:
You read my mind, i've been thinking about getting the same, but every time i go looking for inverters and batteries the amount of options available makes the process kinda daunting.

We need specifics people. :)
Click to expand...

1. Determine the minimum W you need. Look at the back of your device or power supply and add up the W's. Now you know what size inverter you need.
2. Spend a bit more and get a pure sine wave inverter as your electronics prefers it.
3. Decide if you want to go solar panel plus regulator. Obviously higher cost and installation plus you'll then use deep cycle batteries. Else if you just want a cheap setup get the cheapest battery (car or deep cycle) and a battery charger to charge up after load shedding.

You need to keep your draw to a minimum or else you need bigger/more batteries and a larger inverter.

If you want to get through a 2-3 hour load shed then, at a guess (best to contact one of the suppliers), look at a 70-100 Ah battery and 200-300 W inverter. The trick to battery longevity is not to drain it past 50%. Only connect low power devices like CFL/LED lights, modem, laptop etc. Forget about desktops, big screens, heating or incandescent lights.
 
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You need to calculate your requirements first and then go from there. Using your example:

Running for 4 hours each:
32 inch lcd tv: 150wx4 = 600 Watt Hours
Explora 30watt?: 30x4 = 120 WH
Light 15watt power saving 15x4 = 60 WH
Computer 500watt? 500x4 = 2000WH

Thats a total of 2780 Watt Hours that you devide by your battery voltage:
2780/12 = 231 AH of batteries needed(you will damage the batteries if you totally drain them so you need about twice that)

150w+30w+15w+500w = 695W continuous that you need for the inverter.

So in your case I would suggest 4 100AH batteries and a 1000w pure sine inverter(You can chance a modified sine wave invertor but it is not ideal).

Ellies pure sine 1000W R3,768.00
Cotek pure sine 1000W R5,390.00

Omnipower Modified sine 1000W R1,531.00

Delkor 100Ah 12V Deep Cycle Battery X4 R7700

So you are looking at R9-12000 excluding the chargers to run the items you listed for 4 hours with a basic setup.

prices from http://www.sustainable.co.za/


its a pretty pricey investment and the batteries need to be looked after properly or you will end up damaging them.
 
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Beachless said:
You need to calculate your requirements first and then go from there. Using your example:

Running for 4 hours each:
32 inch lcd tv: 150wx4 = 600 Watt Hours
Explora 30watt?: 30x4 = 120 WH
Light 15watt power saving 15x4 = 60 WH
Computer 500watt? 500x4 = 2000WH

Thats a total of 2780 Watt Hours that you devide by your battery voltage:
2780/12 = 231 AH of batteries needed(you will damage the batteries if you totally drain them so you need about twice that)

150w+30w+15w+500w = 695W continuous that you need for the inverter.

So in your case I would suggest 4 100AH batteries and a 1000w pure sine inverter(You can chance a modified sine wave invertor but it is not ideal).

Ellies pure sine 1000W R3,768.00
Cotek pure sine 1000W R5,390.00

Omnipower Modified sine 1000W R1,531.00

Delkor 100Ah 12V Deep Cycle Battery X4 R7700

So you are looking at R9-12000 excluding the chargers to run the items you listed for 4 hours with a basic setup.

prices from http://www.sustainable.co.za/


its a pretty pricey investment and the batteries need to be looked after properly or you will end up damaging them.
Click to expand...

It is important to remember that these appliance only pull the maximum power during start up. E.g. a pc with a 500W PSU does not use 500W the whole time it is running. I am not sure what the % is that it uses after start up, but I'm sure the info is available somewhere.
 
As awesome as inverters are, batteries needed to power them are bloody expensive, I've got a 6kw Generator that runs the whole houses lighting (All LED), TV's, fridges and one geyser without a problem, cost R4k back in the day. I modified its exhaust to fit out of a window in an outhouse so you can't hear it when its running unless you actually stand in the outhouse.

Point being, generators are cheaper and provide more power, but they are bloody noisy! and unless you and your neighbors can live with the noise, soundproofing is a must, which is where inverters reign supreme, they are virtually silent.
 
MightyQuin said:
It is important to remember that these appliance only pull the maximum power during start up. E.g. a pc with a 500W PSU does not use 500W the whole time it is running. I am not sure what the % is that it uses after start up, but I'm sure the info is available somewhere.
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Yip I was intentionally over estimating because I dont know what is meant by a pc Dual 26 inch screens 5 hardrives and 2gfx cards with neon lighting or a laptop. My microservers use about 70watt when idling along doing minor duties and a normal desktop will probably be 200-300w with 50w or so for the screen.

There are quite a few sites that will give you your components average watt ratings so its just some research to work out your needs.
 
biometrics said:
For a sensitive electronics like a PC you should use a sine wave inverter.
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Though you can probably get away with square wave...like 90% of the UPS out there pump square when on battery so most PC equipment seems to cope with it especially if its a decent PSU.
 
I completely endorse biometric and Beachless's recommendation of a true sine wave inverter - I run my house on a 12kW model. But it's also true that pretty much anything that simply converts your 240VAC back to DC will be fine with a square wave inverter.
 
Does the use of inverters not cancel out the idea of loadshedding ? Surely while you are charging your batteries again you are putting strain back on the grid. One would think using solar will be better ? I may be wrong so forgive my observation :)
 
Dan C said:
Does the use of inverters not cancel out the idea of loadshedding ? Surely while you are charging your batteries again you are putting strain back on the grid. One would think using solar will be better ? I may be wrong so forgive my observation :)
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If you're using the grid to charge your batteries, all you're doing is time-shifting your load (and losing a bit in translation).

You're not gyppoing the load shedding system because your load is at an "authorised" time.

Charging with solar PV is great, of course. But it does require a relatively large investment in panels.
 
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Dan C said:
Does the use of inverters not cancel out the idea of loadshedding ? Surely while you are charging your batteries again you are putting strain back on the grid. One would think using solar will be better ? I may be wrong so forgive my observation :)
Click to expand...

You are right, but the idea would be to charge the batteries during off-peak times so that the grid can handle it.

Thereby smoothing out demand.
 
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