Good day Guys

I`m in the process of building a house and will be completely of the grid. I`m looking at 8000w system and will ad on as required in the future. Can anyone please give me an estimated price range for such a system. Should be a high quality and reliable system with low or zero maintenance on the batteries as I`m working out of country and the misses will be left with the issues while I`m gone

It really depends on the kind of products you put in, and how much power you're looking to make in a day. If you go with a flagship Victron 10kva Quatro, you're talking 75k just for the inverter. Assuming you need make 15kwh a day, you'll need around 3kwp of solar power, which is going to set you back another 25k or so. Then you probably want a good MPPT charge controller, where both the 100A Microcare and the Victron 70/150 is going to set you back another 10k. So it's 110k just for the three main components.

 

Now add batteries. Around 60k will buy you a 48V bank of 500Ah-600Ah deep cycle 2v cells. So we're up to around 170k.

 

Now you need mounting hardware, cabling, odds and ends (fuses, breakers), and man-hours to install it, so let's just say it's going to be an even 200k for that system.

 

You can go with a cheaper inverter too. The guys around here love the Axpert, and I believe you can put two of those units in parallel for the same capacity, and you'll pay less than half of what the Quatro costs (around 20k), which still leaves you with a good 150k outlay. Which is why I say... it really depends on the products :-)

HI DeWet

 

Welcome to the forum.

 

I am not going to get involved in price but rather ideas, since you are going to be away a lot of the time.

 

• Since you are starting with a new home LEDs,  A++ fridge and A++ freezer are a must. Every appliance you buy, have a look at it rating. Perhaps take an Efergy plug with you to the store and look at the draw on TV etc. More often than not other appliances are not plugged in, but look at their manuals on the internet. (All our appliance manuals are saved in one folder in Google drive).
• Since you are going to be off grid I would have two inverters in parallel (Victron 5kW) would be a good choice. Thus if a inverter fails your missus will not be without power.
• A battery bank to give you 2 days autonomy (3 days if you live in KZN or the Cape peninsula and environs).The batteries should probably be sealed. They might not last as long as vented batteries but will not need routine maintenance. If you are in the country every 5-6 weeks you may get away with vented batteries.
• A standby generator that automatically kicks in should your batteries voltage drop too low. Honda make standby petrol generators that produce a reasonably clean output that would be compatible with most inverters.
• Panels are relatively cheap you can over spec on them and then organise to run most of your heavy loads during the day when the sun is shining. 

Just some ideas to ruminate over

 

Chris

Also water heating system

Indeed, I was just thinking that TTT should be here shortly to tell you that you ought to ask what you NEED, not what you WANT :-) So downsizing your consumption side first as Chris says is the way to go, and a large part of that is to immediately take hot water out of the equation, as Regie says. Move the cooking to gas (which is NOT cheaper than electricity per unit of energy at municipal rates, but so much more convenient and makes so much sense within the larger picture), and suddenly you need a much smaller system.

 

I can run all the important stuff in my house with a system that cost < 50k (that makes less than 5kwh a day)... because the important stuff are all energy efficient :-) Of course that is not what I actually do... we love our entertainment and tumble dryer way too much for that :-)

Indeed, I was just thinking that TTT should be here shortly to tell you that you ought to ask what you NEED, not what you WANT :-) 

 

Plonky your career in the software industry is a waste of your talents. You should be in entertainment, specifically comedy.

Hi DW

We live on a farm in the Karoo.

The buildings at our place were planned from the outset not to support Eskom.

We have 15 250W panels, a 100A MicroCare charge controller, a 5kW M/C inverter and 12 Narada REX-C200 batteries.

All the lights in the buildings are LED's. The fridge/freezer A++, the gas stove has an efficient electric oven. It seems that the European stoves use less power for the oven than the local ones.

Yesterday the oven and dishwasher were on simultaneously. Once I saw them pulling 4600W. The system was keeping up nicely. The controller said that it was putting 3100W back into the batteries.

You can find prices for e everything you need on the internet. Shout here if you're in doubt about something.

If I were to build the system again, I'd probably do it exactly the same.

Thanks Guys

This is awesome to have somewhere to turn to, What you are saying is a lot of help. The decision to go off grid was a huge one and we understand that this is not only a choice but a lifestyle and will need a lot of management to succeed.

The stove is Gas-gas with only the rotisserie and the oven light that needs power.

The water heating will come from two high-pressure solar geysers and a gas one for backup in the main bathroom.

I`ll insure that all lighting is led

Thanks for the tip on the A++ fridge and freezer.

That leaves me with the dishwasher, pool pump, and irrigation system which will need to be operated during peak sun hours.

The Idea to go with two inverters in parallel will insure that there is some power if something goes wrong with either system.

I`ve got two quotes and both is much more than what is spoken about.

I don't want to stir anything but will put the quote up for you to see, this is the one I`m interested in. the only real concern is the Power-box in this quote which is a very fancy box for all the equipment to go into but with a R15 000 rand price tag, I`m not so sure.

Louis Jordaan, 08 October 2015, Off-Grid EnergyBox Revised.pdf

That EnergyBox might include a amp-hour counter like the Victron BMV-702 as well as a large DC on/off switch. I remember when the guy at ExSolar told me I needed one of those too, showed me this nice orange steel case with the big handle switch on the front and the BMV next to it. Then he told me it's 5.5k (or something like that), and this was two years ago :-) That is to say, it might not be completely ridiculous, just find out what it is :-)

 

Dish washer: I have a Bosch energy-efficient unit. It uses around 1kwh per wash. Peak is around 1800W, and only for a short time (to heat a little bit of water).

 

I almost cannot stress the importance of the fridge/freezer enough. Two years ago I had two cheapie combo units that came from student days and just refused to die. While it is a testament to their brilliant longevity, they each used 3kwh a day, for a combined 6kwh. I more than halved that number.

 

Fridge, I have a Bosch KSV36VL30. I got it on special for R7500, but if you shop around you can find them under 10k still. Uses less than 1kwh a day. 90w compressor. LED light inside. Lots of space, vegetables and milk actually last longer, etc. I found out I'm not the only person who felt that way after reading this German review, especially where he says he only needs to go to the shops once a week (because of the space) and he's convinced the vegetables do last longer:

http://www.amazon.de/gp/customer-reviews/R3NS5XF13Y7XIV

 

(If you don't read German, I suppose that might be a problem :-) )

 

Freezer, now that was a problem. I wanted a chest-freezer, but I couldn't find anything from Bosch or AEG in that configuration. I ended up buying a Defy. Not kidding :-) It's a 210 liter (there's also a 330l model) A-rated unit, also has a 90w compressor, also uses around 1kwh a day. Since it only cost R1999, it has already paid for itself in power savings.

I am not sure what the "Energy box" is but it appears overpriced. Why two of them? If it is for the inverters then one decent DB box wired for both inverters should cost less than 3K. (5K at the outside if you have complicated circuits - but then you need one whether you go solar of go Eskom so it is actually part of your building cost).

Everything looks just a 1-2K more expensive compared to when  I installed in July. That may be a product of our exchange rate (Inverter R10k, 250W panels 2.2K and same batteries R3500 ex vat). Try Rubicon I know they have a office in JHB.

 

I shopped around for about 2 months before purchasing. You may not have that luxury.

 

Good luck with the install and post pics.

 

Chris

1st, what is this 5kva Hybrid inverter for R12k?

Looks like these days anything is called Hybrid

Get the correct details on the quote, any quote for that matter, before you proceed, otherwise they can install anything!

 

If you going completely off the grid, look for inverters with better efficiency figures, the Axpert units is cheap, but not in the most efficient.

Battries, your 520Ah is NOT going to cut it, not if you going full offgrid.

Remember, you should only use 50% of that 520Ah, otherwise you going to hurt the battries.

Rather look at the decent solar 2V cells at around 800Ah or more.

 

Ideally you would like to be able to run 2 to 3 days just on battries.

Your solar should be able to feed all loads during the day and still recharge the battries as well!!!

Hi guys

The Inverters is the (Replus sineON IM5kva-48v) made by Renesola.

The power-box is not that fancy at all with the Amp hour meter like Plonkster mentioned.

I`ve attached some of the specks of this system. But I don't thinks it`s the best system for the moneys worth.

Thanks a lot.

Replus SineON IM3KVA-48-V and Replus sineON IM5KVA-48-V Datasheet low res.pdf

ENERGYBOX CABINET SPEC1 E (1).PDF

Hi guys

The Inverters is the (Replus sineON IM5kva-48v) made by Renesola.

The power-box is not that fancy at all with the Amp hour meter like Plonkster mentioned.

I`ve attached some of the specks of this system. But I don't thinks it`s the best system for the moneys worth.

Thanks a lot.

 

The Replus is just a re-branded Axpert - as Wetkit mentioned, not a true hybrid and not the best option for an off-grid setup.

 

 

The power-box is not that fancy at all ....

 

 

 

.... but at a fancy price. (and you need two of them).

 

My advice DeWet is to try source components individually and see where you get. In the mean time scout around for an installer who will just do the installation or do the install and supply some of the components. That way you get what you want/need (up for debate TTT ) and not what someone else thinks you need.

 

The quotes for the supply of a "Total System"  that I received (R 400k +) and have seen tend to be expensive. Doing it yourself (if you have the time) is an option and obviously knocks between R20 -30k off the price but you will need someone to come and check your work and if he does the job properly that will cost a couple of thousand.  

I see I am being referred to here. 

 

Well, the fact is that if your house is going to be off-grid then there are no more wants versus needs, all have just become needs.    

 

And people who go this route has got the power saving devices in place already, for it becomes very expensive very fast if you do not do that. 

Having said that, saving 500w here or there is not going to make such a huge difference for an entire house that runs with no Eskom.

 

100% off-grid is a total different mindset.

 

@DeWet - have a squiz at Victron products also.

Controllers from Morningstar and Outback as well as Outback inverters.

Pricey, most definitely, but is there a problem at just looking? 

Thanks to everyone participating in this topic, I am indeed much more informed and will take a lot of advise from this to move forward.

I disagree TTT. Even for full off-grid, there is still want and need. I WANT an air conditioner. Given the extra cost of powering it... do I really need it? Or shall I jump into the nearby dam to cool off? :-P

  One of my friends, his aircons are needs, no joke. Even his UPS can cater for it.

 

If it was me, with a house off-grid in a hot place, a aircon is a need. Long hot summer day, lots of sun, the more you need the coolness.

 

You get very efficient ones nowadays, so for the price of a few more panels for just the aircon on hot days, problem is solved.

And those same panels in winter, no aircon needed ... problem solved again. 

For the guys who helped me on the discussion above, just an update of were I`m at this stage.

I`ve found the perfect system for my needs in the Victron series and with the help of Deltech only paid a fraction more than the so called energy box mentioned on top here. The installation was done professionally and with care to the infrastructure of the house. I am fortunate to be able to sell all the long coming appliances from the old house in town and replaced it with A++ equipment from Bosch. They truly exceed the needs of ultra light power consuming appliances.

  :D  

solar.zip

Nice that they could do a deal for you. At that price I would probably also go for Victron.