Inverter, batteries and a Solar panel or 2

Greglsh

Greglsh

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Hi

Please can I have a few suggestions. I am looking into getting an inverter for when we have no power. All I want is to run a 47" inch LG led tv, 2x dstv decoders and maybe 2 to 3 lights for now. What I would like to do is start off small but with the option of being able to add-on later. What I was thinking is to get an inverter that can accept Eskom power as well as solar power and this in turn must charge the batteries, and maybe 2 solar panels to charge the batteries during the day.

What can you suggest, E.G. Make and model of inverter/charger, how many and what type of batteries and panels and where is the best place to look in Durban. I don't want to go cheap on the inverter/charger as I might want to upgrade to more batteries and more panels later. I have heard of Victron what other brands are good? Thanks
 
S

StellenboschStudent

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Greglsh said:
Hi

Please can I have a few suggestions. I am looking into getting an inverter for when we have no power. All I want is to run a 47" inch LG led tv, 2x dstv decoders and maybe 2 to 3 lights for now. What I would like to do is start off small but with the option of being able to add-on later. What I was thinking is to get an inverter that can accept Eskom power as well as solar power and this in turn must charge the batteries, and maybe 2 solar panels to charge the batteries during the day.

What can you suggest, E.G. Make and model of inverter/charger, how many and what type of batteries and panels and where is the best place to look in Durban. I don't want to go cheap on the inverter/charger as I might want to upgrade to more batteries and more panels later. I have heard of Victron what other brands are good? Thanks
Click to expand...

TV will consume max 150W, DSTV decoders (not 100% sure) 200W, couple of lights (typical 80W bulb x 5) 400W. So you are looking at about 800W system. That is extremely small, typical household systems are 3-5kW.

As far as the inverter goes, the grid-connected once are expensive. Omnipower is ok, but I would go for any German made hardware. That will set you back at least R3k (for a 1kW device), they get even more expensive if you want to charge batteries.

As for the panel, you should be able to buy normal Si-based panels for roughly R6-R8 per Watt, rounding to about R6500 for the panels.

As far as the batteries go, it is still very expensive. Lithium batteries will last the longest, but are crazy expensive. Best bet is lead batteries (similar to car batteries but can go through numerous charge/discharge sequences). Adding batteries also adds another level of complexity like battery charging unit and all that. I guess you would like to run off the batteries during night time load-shedding. This means you have to calculate the battery size to give you 800W for 2 hours. Typical 75Ah (@ 12V) battery will set you back R3k, you will need 2 of those to give you 24V to run the TV and decoders (maybe they will work of 12V, not sure of the specs).

All in all you are looking at R15k and upwards. Inverter should last you a long time (20years+), panels should be ok for 10-15 years (not sure about the extreme humidity in Durban, might cut that short), batteries 5 years if you are lucky.

EDIT: http://www.sustainable.co.za/sustainable-solar-power-kit-six-800wh-solar-power-kits.html
I don't the company (seems legit). I also don't know about the inverter and charging unit in this kit, seems ok.
 
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akescpt

akescpt

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80w bulbs? what century you living in? even cfl's are really bright and come in at 15w. LED's even smaller at 6w/7w. OP should get an 800 inverter generator @ R2.8k and be done with it. a 15k outlay for 800w seems a bit much.
 
S

StellenboschStudent

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akescpt said:
80w bulbs? what century you living in? even cfl's are really bright and come in at 15w. LED's even smaller at 6w/7w. OP should get an 800 inverter generator @ R2.8k and be done with it. a 15k outlay for 800w seems a bit much.
Click to expand...

Depends on how bright he wants his lights...
Ok, sorry, 15W bulbs, x5, recalculating.... 400W system, should suffice then.

400W inverter (grid tied) maybe R2k, panels R3k, batteries R2k, all the rest R2k.

http://www.sustainable.co.za/sustainable-solar-power-kit-four-300wh-solar-power-kits.html
 
Drifter

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spiff

spiff

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my system was not that expensive:

1 x 12v 102Ah lead acid deep cycle battery - R1050-00 (first national battery)

1 x smart charger R1850-00 (first national battery)

1 x 1000w pure sine way inverter - R2500-00

I run the following:

1 x dual view SD PVR decoder

1 x CRT tv

planning on adding a 14w CFL soon

had it running for 3hrs the other night because eskum could not get our area switched on :mad:
 
Drifter

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spiff said:
my system was not that expensive:

1 x 12v 102Ah lead acid deep cycle battery - R1050-00 (first national battery)

1 x smart charger R1850-00 (first national battery)

1 x 1000w pure sine way inverter - R2500-00

I run the following:

1 x dual view SD PVR decoder

1 x CRT tv

planning on adding a 14w CFL soon

had it running for 3hrs the other night because eskum could not get our area switched on :mad:
Click to expand...

CRT TV, that consumes more power than say a 51" Plasma would, right?
 
S

StellenboschStudent

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Drifter said:
And with this I can run a few lights, decoder and TV? Guesstimate of installation costs?
Click to expand...

Yip, should be able to do all that with 300W. Installation can be free if you do it yourself, not that hard :)
An electrician will probably ask you R250 an hour (???) and it shouldn't take more than a couple of hours, so lets say R1000 for installation. But I base this on absolutely nothing.

spiff said:
my system was not that expensive:

1 x 12v 102Ah lead acid deep cycle battery - R1050-00 (first national battery)

1 x smart charger R1850-00 (first national battery)

1 x 1000w pure sine way inverter - R2500-00

I run the following:

1 x dual view SD PVR decoder

1 x CRT tv

planning on adding a 14w CFL soon

had it running for 3hrs the other night because eskum could not get our area switched on :mad:
Click to expand...

The single 12V battery enough?
You can always get stuff cheaper if you buy local products or even cheaper imports. My personal preference in just to the more expensive side as the components usually last longer. Don't want to pay R2500 for an inverter every 5 years, rather pay R5k and it lasts 10+years.
 
spiff

spiff

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The single 12V battery enough? Yes bought it last week. had a similar system back in 2008 running the same CRT tv and SD PVR decoder, but with a deltec 105Ah battery running a 750w basic inverter. (R500-00) the Deltec died last month :( hence the replacement and upgrading.

I can add another 12v battery in parallel if I need to.


You can always get stuff cheaper if you buy local products or even cheaper imports. My personal preference in just to the more expensive side as the components usually last longer. Don't want to pay R2500 for an inverter every 5 years, rather pay R5k and it lasts 10+years.

not really - my 750w el cheapo R500-00 inverter from brights Plattekloof still works after 7yrs.
 
AfricanTech

AfricanTech

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Can anyone recommend someone in Cape Town who would be able to do such a job at a reasonable price.

Thanks
 
C

CraigS2

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Subscribed as well. Why can't some entrepeneur (an electrician maybe) put together a package like this for light medium and heavy users. He'd make a packet.
 
N

Niner

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Ok, so I have some questions.

I'm looking at going this route as well - initially just for loadshedding, but with the option to expand.

I'm looking at a 3kW Victron Multiplus inverter.

1'st question - 24v or 48v? And if I calculate that I need 250Ah of battery life(already accounting for dod), do I need 2 12v batteries in series for 24v(and 4 for 48v), to get the same amperage? What exactly would be the benefit of going 48v over 24v then?
 
The_Traveller

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Niner said:
Ok, so I have some questions.

I'm looking at going this route as well - initially just for loadshedding, but with the option to expand.

I'm looking at a 3kW Victron Multiplus inverter.

1'st question - 24v or 48v? And if I calculate that I need 250Ah of battery life(already accounting for dod), do I need 2 12v batteries in series for 24v(and 4 for 48v), to get the same amperage? What exactly would be the benefit of going 48v over 24v then?
Click to expand...

That's a good inverter, but $$$ ... anyways to answer your question ...

you're right, to add voltage, you need to wire in series.

The advantage of a 48v over a 24 is that you will have extended backup time ... for example ...
If your load is 1000w ...
on a 24v system - 1000/24 = 41.66Ah
on a 48v system - 1000/48 = 20.83Ah

So if you using 12v100ah batteries, then on a 24v system .... 100/41.66 = 2.4 hours
on a 48v system ... 100/20.83 = 4.8 hours

ALL OF THE ABOVE IS NOT TAKING INTO ACCOUNT INVERTER EFFICIENCY, BATTERY DC CURVES ETC. JUST A QUICK LOOK AT WHY A 48V IS BETTER THAN A 24V , BECAUSE YOU HAVE MORE BATTERY.
 
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BigEars

BigEars

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The_Traveller said:
That's a good inverter, but $$$ ... anyways to answer your question ...

you're right, to add voltage, you need to wire in series.

The advantage of a 48v over a 24 is that you will have extended backup time ... for example ...
If your load is 1000kw ...
on a 24v system - 1000/24 = 41.66Ah
on a 48v system - 1000/48 = 20.83Ah

So if you using 12v100ah batteries, then on a 24v system .... 100/41.66 = 2.4 hours
on a 48v system ... 100/20.83 = 4.8 hours

ALL OF THE ABOVE IS NOT TAKING INTO ACCOUNT INVERTER EFFICIENCY, BATTERY DC CURVES ETC. JUST A QUICK LOOK AT WHY A 48V IS BETTER THAN A 24V , BECAUSE YOU HAVE MORE BATTERY.
Click to expand...

The devil is in the detail....
 
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