Sophon

Thanks. Verify with my meter how, by measuring the resistance between panel and supports?

How have you guys grounded your solar panels? My solar panels will be ground mounted and each panel will be attached to the support metal structure (which will be bonded to the ground rod) with 8-10 screws/bolts. Will that be enough grounding, or should I run wires from the panels to the metal support or even to the ground rod?

link

Why pay USD 36 for a 200AH battery, when you can get a 280AH battery for USD 20 from the same seller: The seller seems to be genuine and has very good reviews, but there is definitely something funky going on with some of their pricing.

I wonder if the calculator from the European Commission is biased towards colder climates: If we compare the numbers from January and August, I would be producing more than 4 kWh per day more in January than I would in August. That is reflected in the fact that the calculator expects me to fully charge my battery 29 days in January against only 22 days in August. However, the calculator for some reason also expects me to run out of battery every single day in January but only on 21 days in August. That makes no sense to me. The only reason I can think of is that the calculator expects me to use more energy in the winter for heating (it has the battery running out every night in November, December and January), or that it somehow expects that the battery is used for an extended time because of longer nights. That is not really the case in Thailand, where we as a general rule probably use more energy during the night in August (Air condition), and where the difference in day/night hours doesn't wary much from summer to winter. Maybe the calculator has some constants in the calculations that are more relevant for Europe than Thailand. It is after all an calculator supplied by the European Commission. Can anyone come up with a plausible explanation?

Where in Thailand is the Global you use?

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).