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Everything posted by PaulF007

  1. I would suggest you first go to an Auto electrician with a multi meter and ask him to show to you the difference between parallel and series connections else you almost certainly are going to create some magic smoke... Dc is not something you should bugger around with if you don't know the basics. 12v is fairly low but the Amps could burn you badly....
  2. As far as I know yes , but they also have an extensive Wiki page so if you are not sure of the device have a look to confirm. The basic is very well supported but you could also have a look at the Wemos d1 mini. You can have up to 8 io ports in one device.
  3. Have a look at Jonathan Oxer's website , he has been involved with house automation for many years. Interestingly he moved away from all interfaces and is now using Node Red UI for his system.
  4. Been using Openhab now for almost four years . Here is a LINK of the setup I posted on another page. Personally I tested both and the reason why I went OH is that they have a Proxy server that works out of the box. You install the plugin register the on the site and add your UUI and Secured code. No need to port forward and it is for free. But apart from that I could not see much difference for what I an using. Also after three years you tend to know the interface so it is "easier" to setup
  5. @Stef that is a cheap android tablet that I used.
  6. It is looking good well done! Here is some additional points to consider. Ensure that the geyser will not switch on while you are on battery power unless it is not a problem and you battery bank can handle it. One way of handling it is to ensure that the contact is powered from the grid feed. Should the grid fail the contact can not close. Have some way of monitoring your battery watts should the draw be lower than ,for example , -2000 w let it switch of the geyser. Have a hard timer in the loop so that the geyser can only be switch automatically during day time unless you do it manually. The assumption is made that you have a non grid tie inverter and that you need to switch between grid and solar if you have grid tie then 2 and 3 is not that important but I will look at 1 for protection of the batteries.
  7. Getting back to the Original question If I do the same "Straight-line" comparison I use about 12 kwh of alternative energy (Solar + Batts) so this will give me R 63 saving per day. Keep in mind I live on a farm with prepaid but no line rental so the price per unit is very high but I only pay for what I use from the grid.
  8. Ok , so this project has been ongoing for the last three of four years and in fact is still going on we have learned a lot on hydro power and possible pitfalls. but I wont bore you all with the details. Here is what the "final" product looks like. Ps. Not my system , hope to have one going in a year or so - (Need to raise the capital )
  9. Still a work in progress. But I have build a dash to display all the different alternative energies on one page.
  10. One more idea , should any one look at this. Most alarms have an audio output , 12v , to drive siren. So 1) Dead simple method - 12v - 220v contact to the lights. They will then come one if the siren is activated and switch off if the siren is off. 2) 12v interval timer. - If triggered run for 10,20, 30 min and then reset. Wire the light in parallel with the relay so that you still have control to manually switch in the lights. There is a ton of other ways to do it but this is , in my mind , the dead simple method if you want to drive it from an existing alarm system.
  11. Looking good. Well done. You should also notice that when you start to run hot water the temp will spike as the hottest water will be on top. As the old saying goes " he who measures will know" ...
  12. @JJS - What is the full speck of your system and how do you monitor your data the values does not seem correct on average you should see conversion losses of about 15% - 20% .
  13. Here is a thought , span the begees out of those contact numbers. Keep the crook busy so he does not have time to scam ignorant/desperate people.
  14. Sure it is quite simple. So i have a SonOff running Tasmota on it . You will need to flash the sonoff with the new firmware. This will add the benefit that you can add atleast 3 sensors to the SonOff , (TX , RX and GPOI14 , I think thats the last pin). In tasmota to you just select the correct sensor for the pin that you connected that DS18B20 sensor. Here is a tutorial as to how to wireup the sensor. The nice part of tasmota is that every thing is already done and you only need to add the broker details and it will publish to sensor data to the "tele/#/SENSOR" topic. Here is some pictures of the Tasmota setup. There a lot of info as to how to flash the sonoff switch with tasmota , alternatively you could also use a Wemos D1 with Tasmota loaded to do the same. Last thing is that I placed the sensor where the normal thermostat of the geyser would go. So that was quite easy
  15. A buddy of mine used a old Android connected to the mains. There is an app that will send you a SMS , guess maybe another trigger if the phone stops charging / grid fail. Simple but very effective. If you want to go one step further you could use something like Tasker (Android) - then you can have all sorts of stuff setup when the grid fails.
  16. True but these are mostly aimed at commercial applications and the rates will me more or less the same. The only difference is that the "hardware' are , in some cases , considered as collateral..
  17. I guess the easiest way to look at is As per usual do you want to save cost or stick it to the man.... If it is the latter - go for it as there is no argument for principle decisions. On the other hand .. In CPT it looks like average cost is about R2.50 per unit if you are going to use less than 1000 units per month - just got the value of a quick google search .. Lets assume that most people can get Prime + 2% , although some of my clients recently go as low as Prime -2 - rather stick to the upper part cause if that one work it will definitely work the other way . Last time I checked a halve decent solar/battery unit wil set you back at least R 150 000 but lest rather work on R 200 000. Interest on R 200 000 @ 9.25% (7.25% + 2%) will be about R 1500.00 pm or R 18 000 - With the bond repayment over 10 years R 2500.00 over 20 years it will drop to R 1800.00 but you will pay more interest. Lets work on R 2500 pm - that would be close to what you would be paying every month for 1000 units. So on the surface it looks like it could make it BUT you then make the assumption that you are now off Grid and not paying CPT else that will add to the cost per month. (Extra 300 units will be R 720.00 on top of your current bond and that will burn disposable income) If you have a R 200 000 setup chances are you will need to change your lifestyle to match your system and as a result you will end up using less units per month if you were on grid. Factor that back into the first calculation and it becomes near impossible to justify setting up solar system on a bond for non commercial use - (Commercial changes it quite a lot as you need to factor in loss of production ectr. ) Also keep in mind that rates are as low as what I personally think it will drop so don't bank on it for too long... Rather start to setup the household to become solar friendly , solar geyser , gas stove ectr. Once you have reached that goal you can then recalculate if it is worth converting. You might find that a small hybrid system to cover you base load and have some capacity available for load shed will be much more profitable in the long run and that you could do without needing a bond or if you need to the saving will justify the cost.. From my side there is one variable that makes it a little hard to factor in and that is battery tech. Last time I checked you could get lithium's for about R 2.75 per unit. In theory if you buy a bank now it will "cap" your cost per unit for the duration of the batteries lifespan and you could offset that against Eskom increases in the future. . Unfortunately as it has been proven over the years in the forum batteries do not last for ever and if they do go it is away messy.
  18. Hello @Abdul Gool I had a slightly closer look at the info in your calculator. I assume that I am missing something so Ill ask In your data collection you ask for the Loan amount , term and rate. Then you introduce a solar-kit/quote into the mix. Is that for reference ? I t seems like it is added on top of the installation amount and will have an effect on the calculations. If the design will be grid tie only and not a hybrid system , keep in mind that the bulk of the users end up here as a result of load shed an the savings part is a "bonus" ( This is just my point of view) Using the Rand amount of the electric bill makes it difficult in a Grid tie scenario as it will depend when the and how the bulk of the units is used. In some of the scenarios that I have used (here a Histogram of your consumption helps) I have found that using a 1kw Grid tie solution could cover up to 80% of your consumption . Here base load will play a major effect. Have a look at the image below. I have a Max load sometimes of 5kw + but the bulk of my consumption is at +- 500 w so a 1Kw system could account for quite a lot of my setup at a much lower cost. When the energy will be used also play's a major factor in grid tie. You could find that some houses is on idle for most of the day as they are at work/school and only surges when every body arrive back at night and cooking/cleaning happens. Not sure if you did , but do you make provision for the bad weather days as well? Most of these might be addressed in your calculations or not even relevant to what you want to achieve but that my 5c worth. As the saying goes - You asked and therefore I answered. Well done on the hard work done so far. It is quite the beast you are taking on there - respect!!
  19. @Abdul Gool Have a look at this thread. It is quite old but there is some basic principals that you could use to refine your calculator. But in my experience the main factor is human behavior , if that changes the cost of solar becomes viable. Also batteries has become a little cheaper and better. But have a look : )
  20. The Battery sensors I build myself and transmit the data via MQTT. The Geyser controller is also part of the automation system. It has a Geyser Wize Controller as the "Master" and then I control the power to the element with a SSR. Rules is done via Node Red and the temp sensor is a DB18B20 sensor placed in the thermostat of the geyser.
  21. So the wife's old S7's battery gave out and after 2 more attempts to replace it with batteries that last I gave up and made a small screen for the Kitchen. Got most of the basic info running on it and so far so good. It also doubles as a small picture frame.
  22. Another way is to pull the data via node red (js) and then post to mqtt.
  23. I have a couple of them running at my place. (I have some arduino boards running so Wifi is not a option) One thing is that you have to keep them on the same line - the moment you go through a DB the signal is shot to much noise. The longest one that I had was about 900m and never had any problems with it. Just for in case it does not make sense DB >>>> PLUG 1 >>>>>>> PLUG 2 -- No problem Plug 1 >>>>>> DB >>>>>>>> Plug 2 - some times work but you will have issues. Also when I run the genny there is just to much noise so then it also does not work ... But that happens once a month on a maintenance run..
  24. There is a lot of variables that we just do not know. As you noted shading even on just one halve of one panel will have an effect on the production of the panels and with that flat angle there is a good chance that there will be shading of sorts.
  25. At that angle you are going to suffer during winter months. Summer will be fairly good in the middle of the day so that could account for the poor performance. Considering the batteries. Looking at your graph again I can see when you charged them at night and the curve suggest that they had a proper charge.Personally I suspect that they might then not be in the best of condition but I could be completely wrong. The only way to know for sure is to get a battery tester and test each battery under full load and check the recovery time. Just make sure that they are all well charged before you do the test else you will not get proper results. If you can not test them at this stage I would not use them during night time. Being in town you are not going to lose that much in terms of costs. You could then use them for backup when load-shed arrives again.
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