Willem

Well it doesn't really matter. As far as I understand most systems run on a 48v nominal bank voltage... so either 24 x 2Vs at 200 - 250ah or 8 x 6Vs etc. I would probably have to look at 200 - 250ah batts if I want more or less 5 kwh available and working on a total bank voltage of 48v x 200 x 50% = 4.8 kwh??? Had 12V batts in mind... thought they were cheaper, but may not have the lifespan of the 2V ones?? The idea of the bank is to simply be some back up power, not to run completely off grid as for that I reackon I'll need quite some more storage capacity...

Well I guess then there's no need to finght a ignorant money hunting scheme... In CoCT it's way to expensive to go for Net metering. Zero export is an option, but say one wants to do it completely legal, would that then mean that you need to get a pre-paid meter that decrement credit when feeded back if you don't want to be on the pathetic net meter tariff system? Because I really have no interest in hasling with pre-paid electricity again, it's a schlep... Mike what can you expect to pay for decent batteries? I reckon if I install 10kwh capacity to be able to use 5 at the most then I'll be fine with the occasional import from the grid. The other problem is that when you install batteries you need to cover the cost of the batteries with the extra money that you save by using the batteries and I presume depending on how many cycles you run and how far you discharge them will depend how many years you can get out of them but I doubt you'll get more that 5 - 6?? I would have been already happy with a R140 connection fee and then net metering... R400 is just totally ridiculous. But yes in the end it still sucks, solar can actually play an important role in the whole picture but greed is a bastard!!! I guess in a 3rd world country we will never reach the level of development than in 1st world countries, some days it just still irritates me... So although there is not enough electricity available they still don't want you to produce your own, and because of unemployment we are encouraged to work more inefficiently and use as little as possible machinery... hahaha what a South African joke...

I would just like to hear a few thoughts on net metering. Is there no way that consumers can force the city to come forward with more favorable net metering tariffs for residential users? Or would you think it's just better to go 0% export and not mind the hassle? It's actually quite sad that the city is so short sighted about using more renewable energy sources. Any thoughts?

I might have mixed up the infini with the imeon... Can the infini also deliver more than 3kw combined power? I just took a look at the spec sheets again and it's definitely mentioned that the imeon can deliver 3kw from dc (combination of solar and batteries) and add to that another 3 kw from the grid to deliver a peak power of 6 kw. So it's specifically mentioned that if the load stays under 6 kw then the imeon will work perfect. Wish they were a bit cheaper...

That's where the infini plus 5kVa looks really attractive with a 5kw pv input and a 7.5kw combined output... Mike did mention that the infini plus 3kw unit can combine the 3kw solar/battery power with 3kw more grid power to supply a total of 6kw combined power if I understood correctly. If it's true then it would at least help to not limit the available power to 3kw because of the unit sitting in line. The nice thing as mentioned is indeed that with this hybrid system when the grid goes off it will simply continue to supply with what it has available... eg. solar or bats. Where as with the normal grid tied inverters you have to go abnormal routes to get power when the grid is off because they are designed as a grid tied systems... For me currently the infini plus 5kw unit looks like a nice option and cheaper than the SMA system I planned and almost bought... which was a SB 5000tl 21 + SMA Home manager (including 2 sockets) + SMA Energy meter + SMA Multifunction Relay for SB which would have added up to around R43k excluding any panels... ouch...

I am also interested in when the 5kw will arrive aswell as the cards... if there's a 5kw single phase available it will be dificult to not go the infini route...

I know this is a old thread but thought of question. What would happen if you exchange the grid for a genie with a grid tied inverter? What will the effect be of the inverter pushing back the surplus to the genie? I'm still trying to figure out a way if I put up a Sunny Boy with energy meter and home manager to run the system from solar only during the day when the grid is off, given that my solar input is higher than my load... It looks like it might be possible to set the Sunny Boy to off grid but I'm not hundred percent sure. Can anyone maybe advise if it's possible to use a sunny boy when the grid is off??

I just read the document in quite a bit of detail. It would seem that if you install any solar connected to your DB board while you are connected to municipality , you'll have to go through the process. SSEG does not specify if you're exporting or not only that you're an embedded generator even if just for own use, you're still embedded. If you're not exporting you'll need to have a device or inverter that will limit export and they will most likely come and install a pre-paid meter. So the way I understand is the only way you can do PV without having to worry about the above is if you go completely off-grid... Now I know this doesn't happen in practice. What would you say is the real necessary steps when installing solar to just at least be responsible in what you are doing? The ones I can come up with: Make sure installation(eg wiring) is done correctly, DC and AC Make sure all grounding is done properly Install isolator switches on both AC and DC side Make sure that the planned equipment comply with the NRS 097-2-1 regulations/specifications. Is there any other critical things that I'm missing?? I wonder if we will get to a point where the city will inspect suspect adresses to do inspections, for instance where the elec accounts are much lower than the history of the same account??

Glad to share!! Sorry for all the spelling errors... will fix them when I have time..

Wetkit here's a few photo's for you that will show the blade installation from closer. The guy in the hub is waiting for the blade to come up. There's two more guys with him that you can't see. He will be the first one to catch the blade by the studs and pull it closer the hub while also stabalizing it to fit into the hub, it's quite a tight fit. You would think he's wearing a harness but in fact he's not. There's to much wires and electronics in the hub that can be damaged by the steel on the harness and since it's rather flippen small inside the inner part of the hub they prefer to not wear a harness... On the photo below you can clearly see the studs in the blade that the guy in the hub will grab to pull it closer. and yes they all need to be lined up 100% before the blade will go in. They have temp. gear inside the hub and nacelle so that they can manually pitch the hub for the holes to line up with the studs. Here is another picture of the blade getting installed. This is with a different main crane from Vanguard. We had two main cranes on site. The one in the picture is a Grove GTK 1100. Not the nicest crane to work with but it has some advantaged when it comes to mobilizing space. This is the last piece of equipment that I loaded from site, it's a 220 ton mobile, Grove GMK5220. The advantage being site manager was also being able to get my 275ton hydraulic boom and 250ton lattice boom crane licenses... And then last but not least, a Kudu decided to scrap my wife's car the one day that my bakkie was in for service... 5:50 one morning 4 km from site... Happily I got out without a scratch.. the kudu was not so lucky... and off coarse the site workers utilized the meat... hahaha

Mike The turbines start to turn in basicly no wind, as low as 1 - 2 m/s (3 - 7 km/h). They start generating power at 3 m/s with blades at fully pitched. The power then increase up to 100% power at 12m/s. If the wind goes stronger the pitch of the blades are reduced to not over power the turbine or let the speed run to high. They actually turn quite slow even thought the tip will move at about 200km/h. Think it was 5 to 6 seconds on a rotation. These turbines are all rated at 1.8 MW but produce 2 MW on 100% capacity. And as long as the wind blows 12 + m/s they generate at full capacity.. However when the wind goes above 20 m/s (+- 70km/h) the turbine control system will pitch all blades to neutral and stop the turbine. Brakes are not applied but the control system wil pitch the blades every few second to make sure the rotor doesn't turn. The highest windspeed that I measured on site was 37 m/s... now that is quite strong (133 km/h). I had to hold on not to get blown away to actually take the measurement. It was only blowing like that for a short while though. Windspeeds of 20 - 28 m/s was very common on site with all works getting stopped. Wetkit If you have a big enough garden then one should fit... The blade gets about 46 high tensile M36 studs (not 100% sure about the size and number) screwed and locktighted into the root end of the blade. You lift it horizontally and install the blades by fastening the nuts from inside the hub. After a certain percentage of the nuts are torqued the hub will be rotated by a temporary motor installed on the drivetrain to align the next opening on the hub for the installation of the next blade. You have to preferably install all three blades at a time, if you can't you have to position the blade in a certain orientation depending on how many blades are hanging as you'll get a uneven load on the bearing. Another interesting fact that not everyone knows, you can't install the last tower section when the wind is above 11m/s because of the natural frequency of the tower. So if you do put it on the tower starts to sway from side to side and you can't get the nacelle on because of the movement. If you leave the last tower section on and the wind picks up more the tower can fail due to the swaying, so you need that 100 ton nacelle and hub on top to change the natural frequency of the whole tower so that it's stable in strong winds.

The 1st tower section gets installed with a 250ton mobile crane. It then gets grouted to the foundation where after the main crane is mobilized to the crane pad to continue with the other 2/3 tower sections, Nacelle and hub assembly and then lastly the three blades. Blade offloading prior to installation. You'll note that the blade in this case is still upright in the transport frames as it came from the ship. Prior to installation the blade will be lifted from the brackets with two small cranes like in the photo, turned on it's side and laid on the ground, the root end on sleepers and the blade on sponges on top a frame. The studs is then inserted into the root end of the blade whereafter it can be installed by the main crane. One of the foundations at Noblesfontein, you'll notice some rock in the excavation (basically it's all rock...). All foundations, roads and cable trenches needed to be blasted because of the rock. The foundation is slightly different to the Hopefield ones but not too much.

Transporting the 76 ton Nacelle all of a sudden becomes a bit more tricky when you attempt it on a 14 - 16% incline on a gravel road.. Front truck is a Actros 6x6 with 15 ton ballast for traction, secon truck is a 8x4 actros hooked onto the 8 axle with a fifth wheel, both trucks needs torque converter for these type of slopes in order for when you get stuck to be able to pull away again. Total combination weight is about 140 tons. Reaching the top Nacelle installation with Nacelle spreader bar/lifting gear visible. The lifting gear to lift the nacelle alone weights about 3.5 tons. Same as above zoomed out.

Building the main crane on one of the most difficult locations on the side of a koppie on the Noblesfontein windfarm near Three Sisters Flat blade transport on Noblesfontein site on one of the steepest hills on site. The gradient is not really a problem for the blades because they are light, they vertical and horizontal curvature of the road is much more problematic with the blades because of the long spine beam of the trailer when extended. Second last blade installation on cranepad #2 on Noblesfontein.

Some photos from the Hopefield site Temp laydown yard close to the site entrance. You'll realise the size of the towers etc when you see them next to the vehicles.. A complete open foundation in the sand excavation on Hopefield windfarm. The sand is excavated deeper and then recompacted before the foundation is cast. The carrier and base boom section of the main installation crane (Liebherr LG1750). The legs swivel outwards to form a 16 x 16m cetre to centre footprint. The carrier as it's shown in this photo weights about 175 - 180 tons.

just checking the first one if it works posting the photos

Wetkit here is some photo's for you from the hopefield and noblesfontein windfarm. You'll be able to get a better idea of the size of the turbines when looking at the photo's and directly measuring it against people and normal size cars...

Regie Quite true. So many people want to go solar to run their stove and geysers from the panels... Happily the house I bought roughly a year ago already had a 5 plate gas stove as well sa geyser with evacuated tude system on the roof. It's a pump circulated system so I think the little pump uses like 40 or 50w to circulate but it works well. It summer the element is completely switched of via the geyserwise control panel and reaches between 50 and 75 depending on the weather. I can get down to about 16 - 18 units per day for the total household including pool pump so I'm looking to go grid-tied for a start and then later try and move to off-grid. For now just getting all the ducks in a row to start the whole setup...

I would not have been so comfortable with this batteries for the long run... I have limited knowledge about batteries at this stage but inside a battery the is a lot of eletron exchange happening being electric current flowing, I'm just wondering if the lead plates will still have the same composition on a secondhand battery in term of free electrons etc... Haven't read up about it but to simply clean the lead plates you are still using the old lead plates... Maybe someone else with more theoretical battery knowledge can comment on the above statement??

Thanks, I missed them on my searches... prices also not bad... so I quess at least if I want to go SMA I can leave import and buy here...

Thanks Wetkit I'm busy checking out MLT now, looks like they supply SMA as well also at reasonable prices compared to sustainable.co.za which was the only site that I could find prices on for SMA in SA... If I can get it for the prices or around the prices in MLTs price list then I'll buy it locally if I decide to go with SMA at all. You always have risk when importing yourself so you'll have to decide if the risk is worth the money you're saving... At some point I need to also realize that although nice features will be nice, the probability is high that after a while you will set it and leave it and then you paid a lot for features that was nice to play with in the beginning but doesn't get used later on...

hmm that was one of the questions I had if it's the normal 3kw or the plus, if it's the plus and it can take up to 4.5kw solar input then it should work allright, it will just give you the extra edge to make sure the batts keep up and also if you have a full 4.5 kw of panels on you reach the 3kw output on the inverter quicker especially in winter. The infini is definetly starting to look like a real option especially value for money but it's quite difficult to let go of the SMA setup I had pictured... as the SMA gear looks really nice especially what you can do with the home manager... here's a link for you for the software.. http://www.sma.de/en/products/planning-software/sunny-design.html#Downloads-9366 Really curious what your view are on the software as someone that actually works with the stuff...

For that R400 grid export is not worth it I would think. With the rotary meter however if you do not export huge amounts in order that you export more than you pull from the grid then your meter will only reverse but won't go lower than the previous months reading. The R400 pm is really pathetic, they want to make sure that they don't loose money by you putting up solar... On the infini solar, I think the 10kw is a 3 phase if I'm not mistaken... so a bit useless for single phase... Could you perhaps find anything that indicated that you can put more than one infini hybrid inverter on one system and have them communicate? So that you can effectively double your inverter size to 6kw with 2 x 3kw? I know with the SMAs you can link a few devices and they will intelligently work together... again as far as my limited knowledge goes... I know it's probably a bit illegal but I'll be very temped to use the municipality as a ''battery'', even if it's just a little bit, until I've got real batteries in operation...

superdiy I'll be keeping an eye on this thread as I'm also in the process of planning a system. Since you already have a battery bank in your shoes I would have seriously looked at the infini solar and go hybrid. The down side off infini solar is that you only get a 3kw unit but I also can't find too much on them but the upside is that you can hook up your battery bank from the start.... According to the spec sheet there should also be a 5 kw infini single phase unit but can't find anything like that on the net... If you want some software to use for planning, download sunny design 3.0, just use a sma inverter for the exercise, it's quite nice to give your yield for your system with the panels you want to put up and also for the panel orientation and so on. Choose a relevant inverter from their list that will be more or less the same size that you want. http://www.sma.de/en/products/planning-software/sunny-design.html#Downloads-9366 What you mention about the R400 per month for the net metering account, that's as far as I know only or specifically for the City of Capetown. I'm not sure under which municipality Paarl falls.. Well worth it to look into but then again since you already have a battery bank infini or imeon and running hybrid might be a better option for you and skip the net metering. Do you have a prepaid meter or old style disk?

SMA is just so bloody expensive... but they do have a great name and years of proven good service behind them... My head is turning in circles now, before I got on the forum I had a clear idea of what I was going to do and now I have no idea anymore... Almost went so far as to order my SB 5000tl from europe... 1200 pounds plus 200 pounds shipping... + 14% on the 1200 for tax... so would have paid around R28k for inverter on my doorstep... But now my head is turning towards the hybrid route... I just fear that with the 3 kw system I'll not be able to go completely off the grid in terms of not achieving the needed annual yield... If I do get a infini inverter it will mean I can start with 3 kw of panels on the roof from the start with my cash that I've got saved up for the system so that's at least a plus... choices choices... One question. Can I put up 4 - 5kw of panels on the 3kw infini inverter so that it can reach full production quicker to up the yield? Will it discard the extra solar power? I'm currently using Sunny Design just as a reference program to try and size the optimum system. Quite a nice little program to play with for free. Especially handy with the fact that I can put in my own load profile that I get from my energy monitor. Have you used it or any similar software? I'm in Yzerfontein the weekend of 14 - 15 Feb. Any chances that you'll be around?