McWidowmaker

I cannot see the first post in this thread. The forum keeps cutting it to two lines. Clicking go to this post just reload the thread and then cut it to the first two lines again...

I am using 2 x MPPT controllers on the system, but I have been considering to drop those and replace it with a 5kva grid tie. Then I can make something like that work. Cost though is *eek*

Hi Paul, would love to be able to do that with my system, feels ideal to me. I have a full victron setup with the CCGX. I think it is possible to check all that and switched based on it, but I'n not quite sure how.

I have 2 solar geysers in series and my first geyser, that preheats the water runs a geyserwise controller and pump with 24 evac tubes in line. I'm on my 3rd controller and / or pump in 18 months and this thing is driving me nuts. I have tried running a small solar panel and pump only, but with the continuous circulation when the sun shines, heating is really crap. Currently the controller / pump setup is giving trouble again and I'm at wits end with the damn thing. I have an option of an SCR8 controller and 220v pump, but meh, I really dont want to spend R5500 and end up with much of the same. At the moment I am thinking of putting a heat pump on that geyser with a relay on my BMV to kick in when SOC is higher than 90% and trash that solar setup, since its been a pain in the arse since day one and in winter when you really need it it cans most of your gains preventing pipe freeze by circulation hot water through the system and removing the gains during the day. Does anyone have advice or alternate suggestions before I do that?

I am using this setup at the moment. One 150 litre geyser is pre heating the water with a geyserwise / EV pump unit. Its element is disabled and it doesn't use electricity. My second geyser (200l) has an element with a controller, with the EV pipes running straight into the geyser. It only turns on if the water temperature drops below 55 degrees and it receives warm water from the 1st geyser. Benefits: Your main using geyser is the only one with an element. It doesn't get cold water in, the water it receives is usually 55 degrees or more, which means the primary geyser water remains hot Its element works seldom, so the geyser lasts a long time and it doesn't use much power EV running straight into the geyser is MUCH more efficient that an EV flat panel, pump & geyserwise setup My primary geyser is usually at 75 Degrees plus Drawbacks It isn't very efficient when it is cloudy. Although my electrical solar still generate about 50% power, this drops to about 25%. If its raining there is no heat and it will go onto grid / your solar power system There is some heat loss in transferring hot water from one geyser to another. Ensure your pipes are well insulated. If I have to replace the primary geyser or the system, I would do it differently. I would fit a larger 250 - 300 litre geyser with the EV running straight into the geyser. This, when using the sun is much better than the pump / geyserwise setup. Those setups in winter keeps circulating the water at night to prevent your pipes to freeze and really stuffs up your hot water generation. Following this, I will put in a proper gas geyser like the new bosch ones, that measures water temperature at inlet and outlet and only turns on if the water at the inlet is below a certain temperature. Also ensure it has enough flow for your shower & bath to run simultaneous and does not have a pilot flame (Auto ignite). These units are not cheap, last price I got was in the region of about R18k. You also need a gas installation in your house, which most people running solar have because it is much more efficient for cooking. The benefits with such a setup is that it will only switch to gas when your solar isn't working, thus eliminating the need for an element in the solar geyser.

City power Johannesburg have an interesting setup. They do not buy back per se, but if you have any own generation, grid tie or batteries and they pick it up, they charge you what they call a capacity availability fee (ouch). It is a fee, based on the size of your connection 40A / 60A / 80A etc. for them to have the capacity available to you when cloudy days force you back onto the grid. I am generating a fair amount of power in Ekurhuleni grid tied at my business and at my house (off grid), where I haven't bought power in the last 18 months. The house I haven't had any issues with Ekurhuleni yet until now, although their head of power (Fred somebody) told me that they are moving to the same capacity availability fee as CoJ. At my business I have a 35kva 3 phase grid tied solution. I have registered it with the city. They are in process of buying the electricity back, but it will take at least another year, possibly two. They will not do it with single phase house solutions only 100A 3 phase connections and up. At the moment they have supplied me with a bulk meter. I can push back into the grid, but I am getting nothing for it. The meter will only register what I use. I do not yet pay a capacity availability fee, but once they start buying back, they will definitely come. So you will pay something in the region of R2000 a month to have this connection available to you and receive a rebate of 50c per kwh back from council. To break even you would need to push back a lot and only then you will be able to start subsidising your usage at night. You also need to ensure that your connection is well balanced, because if you push back on two phases and draw out in one, you pay for what you take, but get nothring for what is pushing back. You will not be allowed to run into credit so that the council end up paying you for the power supplied. You must remain a nett user of electricity. At the moment I generate about 40kwh more than what I use per day during daytime, but at the same time dont use the grid between 9am and 4pm when it is sunny, which suits me fine.

So, if you have 3 x 200ah 48V battery bank you need 9 balancers? And if you have 24 x 2v cells that you wish to balance you are going to need how many? Wondering if this is really worth while. By how much would it really extend your battery life by and what would the cost vs benefit be? Anyone made some sums regarding this?

Thanks for the info. It may be something to consider when I need to replace my bank i 8 years or so. Lithium is a better option I think, but the price difference had been a deterrent when I purchased my current bank.

I see they are very well priced. Anyone have some experience with them? Looks like I will be able to replace my 48v 600ah bank with one of those for less than 100k, which is awesome for Lithium. 51V bank as well, so it will just slip in where the old one come out. http://www.freedomwon.co.za/home-battery/price-list Looks like its locally manufactured. Thoughts / ideas?

I have to replace 2 airconditioning units that was hail damaged and I am looking for something that won't hurt my solar system. Does anyone have suggestions as to what to look at to replace them with? It is 12 000 and 24000BTU units.

In Ekurhuleni, business tariff, we are currently paying 1.75/kwh. That's about 31k a month if it was here. Awesome setup.

Small business complex with 7 shops.

I have installed a 60kva Kaco Powador Grid tie inverter. I am impressed with the inverter this far. It is a neat unit and works very well. Kaco have excellent local support. The unit I have, have been commissioned by Kaco themselves on site. They come and check everything and make sure that the installation is done correctly and everything work as planned. If the unit goes faulty, they repair the unit on-site. They carry the spares in South Africa and offers a 48hr turn around time, which I think is fantastic. The unit is well priced for what it is offering.

The bulk of the PV panels are east facing. I have about 30% of them facing west at the moment. The system is running 60% capacity. Once Nersa shakes the bull droppings from their socks, I hope to get a proper reversible meter and exp[and it to full capacity and add some more west facing panels. A system of this size is a no brainer. It will repay itself in just over 5 years at current electricity prices.

It has been 28 days since we turned on the inverter. We have generated a total of 6293kwh or an average of 224.75kwh per day from 39040W worth of panels.This generated about R11 000 worth of electricity so far. For sure a worthwhile investment, although I expect to generate at least 30% less middle of next year.