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Sophon

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Everything posted by Sophon

  1. I realize that it's kind of a "how long is a piece of string" questions, but I am just looking for an idea of whether it can realistically be done for around the quoted figure THB 150k (not including building the structure for the panels). I have based my estimate on equipment other people have linked to on Shopee, Lazada: 5 kW on-grid hybrid inverter THB 25,000-50,000 10-12 solar panels 340W THB 40,000-45,000 10 kWh battery storage THB 50,000-80,000 Bits and bobs THB ? I can go higher than that, but if my estimate is completely unrealistic and the minimum cost would be say THB 300k then the project would no longer make sense.
  2. No-one has yet commented on my cost estimate and guesswork about what equipment I will need from my opening post. Does that mean that I am reasonably close, or is everyone just lost for words at my level of ignorance????
  3. When looking at illustrations such as this one of a solar installation in it's simplest form it all seems fairly simple and straight forward: Everything is connected to the on-grid hydrid inverter, and the inverter then acts as the command center deciding where to take energy from (solar panels, batteries or grid), and where to route that energy (house load, batteries or back to the grid). The illustration posted above by Tubulat.. basically shows the same, but just adds more details. But when I then see other illustrations like this one from Crossy's pinned topic about types of solar installations, I start to question if my understanding is correct or if there is something I am missing. Here it seems not everything is controlled by the inverter, instead there is a MPPT charge controller, a mains charger and control electronics (in addition to the inverter) connected to the battery and it's not clear to me exactly how these elements are connected. Mains charger: What's the point of the mains charger? Is it just a fail safe addition to make sure that the battery pack is always charged, even when the solar panels do not produce enough power to both cover the house load and keeping the batteries charged? If that is the case, then I can kind of see the logic in an officially sanctioned installation, when the panels don't produce enough power the batteries are kept topped up from the mains, and when there is excess power from the panels energy is then routed back to the grid. But even so, it doesn't seem optimal given the low feed back tariffs. In a non-sanctioned solar installation where you are not allowed to feed energy back to the grid, using a mains charger seems counter-intuitive. I would want to keep such feed-back to a minimum, so topping up batteries from the grid would mean, that you have nowhere to feed the energy to when your panels produces excess energy. You would either waste the energy or have to feed it (illegally) back to the grid. The one situation where I can see it making sense, is if you have a highly unreliable grid. But maybe I have completely misunderstood the point of the mains charger. MPPT charge controller: As far as I understand, the charge controller regulates the charging of the batteries, which will prolong the battery life. But doesn't most solar battery packs come with some form of battery management system built in? So can the MPPT and the BMS live together, and how much better off are you with a charge controller? Control electronics: What are the "control electronics" controlling? Are they helping out of the charge controller/mains charger? House load: The illustration shows two connections from the inverter to the house load and one directly from the grid to the house. Again, it's not clear from the illustration how you would go about connecting this, which maybe makes it seem more complicated than it really is? Is the direct connection from grid to load some kind of bypass in case the solar system develops a fault? If not, then what is the purpose of this direct link? One of the connections between the inverter and the house load is marked "Essential Power", so presumably this is items such as refrigerators, a few lights, fans etc. that you find essential to have on in case the grid is down and your panels are not producing enough power. The unmarked connections is then the rest, i.e. of the "non-essential" items? The only way I can think of that would make this work, is if your house circuits are separated into essential and non-essential circuits. In my case that would mean a rewiring of the house, something I definitely would not want to do. Normally our power cuts only lasts about an hour, and if one occurs while there is little/no sun and the batteries almost drained I will just make sure to manually turn off everything I don't find essential. It would be helpful though, if it were possible to set up some kind of alarm system in case of power cuts, as we would no longer necessarily be aware of the power being out until the batteries run out. I guess I could ask the neighbour to call us. In reality it wouldn't be a big deal, as even in the worst case scenario (grid down, no sun and batteries empty) we would still be no worse off than we are today. Most of our power cuts happen late afternoon when the thunderstorms roll in, so even on a cloudy day the batteries would typically have some power. So are Mains charger, Charge Controller and Control electronics really essential/necessary/helpful elements? I just want a simple system without unnecessary complications. Of course, if there is a strong argument for including something I am willing to do so, but it should be something that gives me real benefits. I have no doubt got a lot wrong above, so please correct my misunderstandings.
  4. Thank you for your encouragement. If I decide to do this, and at the moment I am strongly leaning towards giving it a try, I will at least initially not export to the grid. I will start out seeing how much I end up relying on the grid, and then decide if I should do some unauthorized export or not. Sooner or later we will lose that option anyway when the PEA changes our meter to a smart meter. I don't think that will be soon though, as our PEA people don't move quickly. I have for more than five years unsuccessfully tried to get them to come out and put a cover on our meter to prevent people from getting electrocuted. I read your story about "commandeering" the crane to have your solar panels lifted onto your roof. I will not put ours on the roof, primarily because I don't really want to have them up there but also because our house have a roof construction with very limited roof space pointing in the right direction (south). Putting the solar panels would also make installation, cabling and later cleaning and maintenance much more difficult. In our case the best place for the panels is about 50 m from our house where the PEA supply goes to a pole on our land before going underground to the house. At this point the cables from PEA is spliced onto the NYY cable going to the house, so "unsplicing" the cables and connecting the inverter would be easy. It's also one of the least shaded part of our land with no shade at all between approximately 7 in the morning and 5 in the afternoon. I plan to put the panels on something like this (only smaller): I have taken the photo near our house down by Tha river, where they have just (after I took the picture) put up 84 solar panels. Not completely sure what the project is, but I suspect power for some kind of pumping station. Thank you again for your info.
  5. The water pump goes on whenever we use water, so many times a day but only for a short while. Rice cooker is on twice a day for half an hour or so, and the kettle once or twice for 5 minutes.
  6. Yes, starting with a hybrid on grid system but without (at least initially) investing in the batteries, and instead using the grid as storage would certainly bring the cost down and increase return on investment. But it would still leave us in the dark when the grid goes down, which does get annoying over time. I have previously thought about getting a generator for such times, but I think a solar system is a better solution. Saving on the electricity bill is not my only consideration, it might not even be the biggest one. I just like the idea of "help saving the world" by generating our own power, and not be concerned with the future cost of electricity or the status of the grid.
  7. I will definitely take the free wall box that comes with my EV, but I have read your posts (and seen the MG podcast) so suspect that the installer will refuse to install it. We only have a 15/45A meter, and our 16 sq.mm. copper cables won't support an upgrade to a 30/100A meter. And I definitely do not want to change the existing 50 m of buried cable, or get a second meter which would then require a second set of cables to be buried. In reality my existing meter should be able to cope with the wall box, but the installer won't see it that way. I will insist on getting the wall box for future install, or to sell with the car if I decide to change it in the future.
  8. As I mentioned, I understand that from a purely financial viewpoint it isn't a slam dunk. however, I like the idea of producing my own energy and not having to worry about future energy price increases. I have the funds available in the bank doing little, so yearly savings of 10% of the invested amount (unless my estimates are off), doesn't sound too bad. I understand that my pay-back time probably won't be 10 years, as there is a good chance that the batteries and/or the inverter might not last that long. My estimated consumption is only 20% lower than yours, and my planned investment only half of what you spent, so perhaps my estimates are off (or maybe you oversized your system?). Thank you for the diagramme.
  9. We live in a small village out in the countryside, so even if I could find someone to install a system at a reasonable mark-up, I suspect it would be next to impossible to get them to come out if sometime in the future I started having problems. The good thing about having done something yourself is, that you know exactly how everything is set up and get an understanding of how the system works. So if you later have problems or want to make changes, you have a better chance of knowing what to do.
  10. Apologies in advance for a long post, but I want to give as much information as possible. I have read some of the topics in the Renewable energy forum, and as some of you have already done it yourself, obviously the answer would be yes. So what I really mean is; can it be done by someone starting out from scratch with little previous knowledge of electrics/electronics? I did all the electrical wiring when we build our house (with a lot of help from this forum, special thanks going to Crossy), and have had not had a single problem over the subsequent eight years, but that is as far as my knowledge of electrics go. Our electrical consumption is fairly limited, so having a professional company install solar at our house would not make any financial sense. Even if saving on costs by installing it myself, the purely financial argument for solar is probably not very convincing in our case. However, my decision on whether to go for solar or not, will not be solely financially based. We have the occasional power cut during thunder storms maybe once or twice per month on average. It’s really not that bad, but if we decide to have solar power, I want to kill two birds with one stone by going for a hybrid, on-grid system. I would like us to be largely self-sufficient, but don’t mind having to draw on the grid from time to time when there is no sun, or our consumption is at its maximum. If it turns out that we draw more energy from the grid than expected, I wouldn’t mind the option to export (unofficially) to the grid to minimize our costs. We still have the old type spinning meters. First a little information about our circumstances. As mentioned our power consumption is relatively modest and doesn’t fluctuate that much between the different months. Our “base consumption” is around 300-500 W, and we only go above 1,000 W if the water pump or one of the kitchen appliances (rice cooker, electric kettle) is on. The only time we exceed 2,000 W if the shower heater (and pump) is on, and I have never seen us go above 4 kW. Over the last few years the consumption numbers have been as follows: 2018: Total cost for the year THB 16,827 for 4,189 kWh. Averages 349 kWh per month or 11.5 kWh per day. Monthly high 394 kWh, low 312 kWh. 2019: Total cost for the year THB 18,427 for 4,504 kWh. Averages 375 kWh per month or 12.3 kWh per day. Monthly high 470 kWh, low 300 kWh. 2020: Total cost for the year THB 16,649 for 4,209 kWh. Averages 351 kWh per month or 11.5 kWh per day. Monthly high 375 kWh, low 321 kWh. 2021: Total cost for the year THB 15,694 for 4,048 kWh. Averages 337 kWh per month or 11.1 kWh per day. Monthly high 372 kWh, low 299 kWh. 2022 (seven months): Total cost for the year THB 10,529 for 2,440 kWh. Averages 349 kWh per month or 11.5 kWh per day. Monthly high 381 kWh, low 295 kWh. The cost for 2020/21 is slightly effected by the Covid discounts, but not the consumption figures. We have ordered a new EV, which will probably arrive sometime at the end of this year or the beginning of next. This will obviously add to our consumption, but as we really don’t drive that much a shot in the dark is that we will consume an additional 1,000 kWh per year for the EV. I plan to almost exclusively charge the EV using a “granny charger” during mid-day on sunny days so as to avoid drawing power from the grid. As our normal drives are only around 50-60 km, a few hours charging at 2.3 kW will be enough to top up the battery again. With the EV added, and figuring in the rising cost of electricity, my costs for electricity for 2023 will probably be somewhere in the THB 20k – 25k range. To get an idea of what kind of battery storage I will need, I logged our consumption for a month from 8.00 - 16.00 and from 16.00 – 8.00 with the following result: 39% of our consumption fell from 8.00 – 16.00 when the solar panels produce power. 61% of our consumption fell from 16.00 – 8.00 there will be little output from the panels, so will largely need to be covered by battery storage. During that month we on average consumed 10.8 kWh per day, so slightly less than a normal month (this was February). This was split with 4.2 kWh during daytime and 6.6 kWh during the “night”. 8.00 – 16.00: Average 4.2 kWh, high 9 kWh, low 2 kWh. 16.00 – 8.00: Average 6.6 kWh, high 9 kWh, low 5 kWh. Only on four days did we use more than 7 kWh between 16.00 and 8.00, so as battery storage is expensive it probably makes more financial sense to only plan for batteries to cover 7 kWh, and draw from the grid to cover any excess. From what I have learned reading other people’s topics, I will need the following equipment: 10-12 solar panels approx. 340 W. 5 kW hybrid on-grid inverter. 10 kWh of battery storage, more would be better but would come at a cost. I believe it should be possible to buy these items for a ball park figure of THB 150k, and they should make it possible for me to save at least 75% on my cost of electricity. So that would mean annual savings of THB 15k+ or about 10% of the investment. My initial impression is that a solar installation is somewhat more complicated than wiring up a new house. But then again, when I first started planning how to wire the house, it seemed fairly complicated too. In the end it wasn’t too bad. So what’s the verdict, do you think I would be able to do this myself (“with a little help from my friends”)? I don’t plan on building my own battery storage as others have done or anything like that. I will be buying ready to go equipment and just put it all together myself. And am I completely off with what I have quoted about costs, savings and necessary equipment to achieve my goal? No need for now to post links to Shopee/Lazada/AliExpress with equipment I can buy. If I satisfy myself that I will be able to do this, I will make follow-up posts to fine-tune the details. If it's a go, I plan to install the system during the dry season, the time between now and then is for planning. Thank you in advance for any input you may have to give (even negative one).
  11. Pro Auto generally come highly recommended by those who use them.
  12. Sophon

    USED SIDECAR

    Why a sidecar, wouldn't one of these be more practical? Readily available everywhere in Thailand, and probably a lot cheaper too.
  13. They changed the rules so there is no longer a 20k Baht exemption, the banks have to withhold tax on any interest amount. However, you can avoid the withholding of tax on savings accounts (not on fixed deposits) if you show your tax id number to the bank and ask them to register it on the account.
  14. If for buying a condo, you cannot transfer the funds in THB. The transfer has to arrive in Thailand in foreign currency, in your case GBP.
  15. This is what the incoming breaker looked like during our build: At least they never replaced the fuses with solid wire. Things haven't got much better since then. This is what our meter have looked like for the last five years, during which time we have repeatedly asked the PEA to come and put on a cover. I have even offered to put on the cover myself, if they would just give me one. The meter is on a public road and in reach of kids and buffaloes (which graze on the empty land next door).
  16. A question to those who own an EV. How much is the road tax in Thailand on an EV, is it the same as on ICE cars? As an example, what would the road tax be on a MG ZS EV compared to a petrol powered MG ZS?
  17. This is what my April International plan says about late payments: No mention of late fees.
  18. Catacanthus incarnatus also known as Man faced stink bug. To see the face you have to turn your pic upside down
  19. A re-entry permit can protect any permission to stay, no matter if that permission to stay was obtained on a visa entry or an extension.
  20. I have received a new passbook for my Bangkok branch account in Lamphun (where we now live).
  21. Almost. A tourist visa will allow you to stay 60 days which can be extended for 30 days.