Sizing a hybrid system for Philippines. I have more info now.

[JoeLansing]

I'm getting closer to having a clue. I'm excited! I'm going to add a link to a quote for a 12KW system I was thinking about, but I don't think I need that many panels now do I? https://drive.google.com/file/d/18rnfzQHeonL4J6cSjuRb-imQ3cWjG36V/view?usp=drive_link

So I actually got a bill, for a fairly heavy use month. 588KWh. I also found this site Global Solar Atlas. I don't understand what it's telling me. Or at least I can't figure out how to convert what it's telling me to a meaningful result. I plug in small home, 8KWp (KWp?) of panels, and get back:

11.680 MWh per year
1700.5 kWh/m2 per year
How do I use those numbers against my 588KWh bill? Divide by 12 and something???? And are those ideal numbers? Clean panels, no clouds, etc.? My goal is to size panels that will run the house, and also keep a decent size battery up that will last for at least 2-3 days of rain. Or limp along at 300KWh per month for weeks after a typhoon. I'm also thinking of doing ground mount instead of roof mount for better efficiency, and maybe ease of covering the panels with plywood or something before a typhoon hits.
Thank you!

 

[DIYrich]

588 kWh per month is about 20kWh per day.
11.68 MWh per year is about 32 kWh per day.
12kW system seems large for 20kWh per day, unless you have bad shading or orientation.

 

[chrisski]

With the Phillipines being rainy, you also have to take into account if you want battery to power these times, like a spare day, or if not, just pay the price for the grid.

I used this to see how much Manilla could get by with to meet a 588 kWh goal per month and it came to about 8 kW of panels. This calculator takes into account rain; that's why production is less on the longest days of the year. You might have 14 days of no production in a row.


I am getting perhaps 9 kW of panels and a 40 kWh battery pack will keep you powered for all but 1 day a week.

 

[JoeLansing]

Thanks for all the good info. I can deal with 14 days of no production in a row if it's just rain. I'm more worried about 6-8 weeks of no grid, and my panels being trashed by a typhoon. I'm hoping to make some plywood covers for a ground mount system to protect them. Any idea on how big of a battery I can toss on an 8K or even 10K system without it being a waste? Would keeping the 300KWh ? battery on that quote make sense if I down size to an 8KW system? I'd like to get 2-3 days on just battery, but I'd only use one of the aircons in the house to stretch it. The house has 1HP, 1.5HP inverter aircons, and a beast 3 Ton non-inverter. I could get by with just the 1.5HP when needed.

 

[DIYrich]

In the USA, 3 days of battery (60 kWh in your case) is the rule if thumb for off-grid. How many days without sun and grid do you want?

For typhoon protection, make the panels easy to remove and bring them inside.

 

[ThaiTaffy]

Not sure how accurate the data is for us in SE Asia I'm currently getting 250% of any projected daily production almost every day. From 760w of panels I get on average 2kwh on rainy days during this time of the year(monsoon season but high sun angle as it's close to summer solstice).

We average 20kwh a day so our usage is similar to yours(air conditioners, pumps, fridges all inverted) not sure if you plan to be grid tied but 12kw is pretty big for your usage and in good weather your batteries will fill fast and all that energy from the panels will need somewhere to go, here in Thailand they set 5kw cap for grid tie so check your local grid supplier and be aware of the limitations they set.

The quote looks ok but inform yourself well first, as from my experience professionals here aren't that professional so best to get as much complimentary knowledge as you can.

 

[chrisski]

Thanks for all the good info. I can deal with 14 days of no production in a row if it's just rain. I'm more worried about 6-8 weeks of no grid, and my panels being trashed by a typhoon. I'm hoping to make some plywood covers for a ground mount system to protect them. Any idea on how big of a battery I can toss on an 8K or even 10K system without it being a waste? Would keeping the 300KWh ? battery on that quote make sense if I down size to an 8KW system? I'd like to get 2-3 days on just battery, but I'd only use one of the aircons in the house to stretch it. The house has 1HP, 1.5HP inverter aircons, and a beast 3 Ton non-inverter. I could get by with just the 1.5HP when needed.

Put some data in that link and see what you get. There’s other sites also like PV WATTS. Location matters, according to the map I saw nw coastal PI is great for solar, elsewhere average. Any shading kills production, for example neighbor’s 40’ coconut tree shading the southern portion of the roof.

So put the pin in the map at your exact town to get better data. Try PV watts.

Having been in okinawa for a while, I can see you wanting to cover ground mount panels for storms. I have not heard of that. I remember a few storms a year.

 

[JoeLansing]

That PV Watts site is nice! This is the data from it for an 8KW system which I think is at my location. https://drive.google.com/file/d/16FfcyW1wR2DXky5kDizy5BIOythguGVM/view?usp=drive_link
This is where my house is https://maps.app.goo.gl/tPXn6aMVvPRLvVWB8

There sure is a big difference between the solar energy on the coast, vs the interior jungle where I'm at.
I have been planning for a grid tied system, but the grid power up there is so trashy. There are black outs 1-2 times per week. I've been told I should get a AVR of some sort to protect my system from the grid. Or will the inverter do that? I can sell back to the grid, but I am only issued credits I will hope to never use, at 1/2 their selling rate. I'm very happy to just have a copy of my bill showing usage, and a web site I can understand to get data from. I need to check to see if there is a size limit to grid tied systems down there.

 

[DIYrich]

I have been planning for a grid tied system, but the grid power up there is so trashy. There are black outs 1-2 times per week. I've been told I should get a AVR of some sort to protect my system from the grid. Or will the inverter do that?

Grid -> charge controller -> battery -> inverter -> load.

That will clean up the power, and ride through blackouts. How much battery depends on your loads and max length of blackouts. This is the cost of getting stable power.

Once you have that problem solved, adding solar now replaces the cost of buying power.

Note: if blackouts last more than a day, then solar can replace some battery.

 

[chrisski]

For the AVR, that would be system dependent, but I doubt it comes with one. The ac input can be fairly broad for an inverter, but I don’t think it’ll protect from a large spike.

You’ll find a balance between solar, generator and grid. Whatever system you go with should accept a generator of equivalent voltage as the grid. That can cover you for the three days of the storm ran a few hours a day to charge batteries. Some inverters allow generators to auto start or remote start the generator when battery is low.

 

[ThaiTaffy]

Don't know the exact model but from what I've been reading alot today the deye/lvtopsun does have a generator autostart feature though I'm kinda becoming more drawn to the solis inverters lots of good reviews and they seem to be cheaper here in SE ASIA

 

[JoeLansing]

Grid -> charge controller -> battery -> inverter -> load.

That will clean up the power, and ride through blackouts. How much battery depends on your loads and max length of blackouts. This is the cost of getting stable power.

Once you have that problem solved, adding solar now replaces the cost of buying power.

Note: if blackouts last more than a day, then solar can replace some battery.

My vision was Panels, Battery, Grid, and House each come off of the Inverter. I probably got that impression from small devices I've seen on Amazon, etc. And now I see the link I posted to the quote I received in my original post was wrong. This is the real full proposal. https://drive.google.com/file/d/1QheKZogHA21dgctpuPNmwcJV6hMoasmG/view?usp=drive_link That line item for Safety Equipment with all the strange abbreviation's is about $550 worth of stuff. Would some of that be a charge controller?
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[JoeLansing]

In the USA, 3 days of battery (60 kWh in your case) is the rule if thumb for off-grid. How many days without sun and grid do you want?

For typhoon protection, make the panels easy to remove and bring them inside.

I want to be low or no electric bill using about 600KW a month, but if a typhoon kills the grid for a couple of weeks (or longer in the case of Odette that went through last year)I want to be able to limp along on half that much each day, with no grid.

 

[chrisski]

I want to be low or no electric bill using about 600KW a month, but if a typhoon kills the grid for a couple of weeks (or longer in the case of Odette that went through last year)I want to be able to limp along on half that much each day, with no grid.

Even in the storm, if your panels were hooked up, they'd produce a little.

After the storm, still slightly overcast, expect anywhere from 1/3 the array wattage to full array wattage in power production. So, for a 8 kW array, anywhere from 2 kWh to 8 kWh. If the sun peaks its head through the clouds, could be more. I live in the desert with 300 days of sun a year, and the one cloudy, rainy day we had since my array became operational 6 months ago, I got 7 kWh from a 10 kW array.

Aside from the house array and batteries, I have a smaller homemade solar generator that I could cook with. I made it to get 3 kWh of power. I usually use a crockpot and draw around 230 watts. I set that up with 400 watts of panels, a 300 watt inverter, and a 1200 wh battery.
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When you do set this up, would be good for you to do some of the calculations yourself if you are not building it. Things like the right wire size so if it is installed by a local electrician, the build is up to standards. I do like the idea serperate inverter, charger, and MPPTs, that way you can swap it out. The solar generator I talked about is back up parts for the RV and vice versa.

 

[ThaiTaffy]

My vision was Panels, Battery, Grid, and House each come off of the Inverter. I probably got that impression from small devices I've seen on Amazon, etc. And now I see the link I posted to the quote I received in my original post was wrong. This is the real full proposal. https://drive.google.com/file/d/1QheKZogHA21dgctpuPNmwcJV6hMoasmG/view?usp=drive_link That line item for Safety Equipment with all the strange abbreviation's is about $550 worth of stuff. Would some of that be a charge controller?
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No the charge controller would be built into the inverter in this case this is just over-current devices, fuses and surge protection, it would be quite interesting to see what brands they would use to charge $550.

 

[DIYrich]

If you are doing ground mount, start on the small side, but plan for a larger system. You can add more panels and battery as you feel out the system, and have more money.

Covering with plywood may help the front side, but wind can pick up the backside. I would try to make it doable to take the panels inside.

 

[chrisski]

@ThaiTaffy Curious, what do others do in your area with these panels for storms with solar panels?

Putting or even covering up 8 kW of panels at 400 watts per panel and 50 LBS each 20 times is no easy task.

 

[ThaiTaffy]

@ThaiTaffy Curious, what do others do in your area with these panels for storms?

My area? Nothing no one has panels apart from small solar lights, there was a few large solar farms nearby on ground mounts but the panels mainly faced north so do you think they worried about storms when they placed the Panels in the wrong direction?
On a serious note being so close to the equator means our panels generally lay alot flatter, 17° latitude here so our panels face south with a 17° inclination so they are far less likely to catch the wind I'd be more worried about debris than wind catching them tbh. There's a few others on the forum who live more southern than me @Norwasian they would likely see more solar installs in their areas but rural NE where I am solar is almost as rare as hens teeth.

 

[Norwasian]

My area? Nothing no one has panels apart from small solar lights, there was a few large solar farms nearby on ground mounts but the panels mainly faced north so do you think they worried about storms when they placed the Panels in the wrong direction?
On a serious note being so close to the equator means our panels generally lay alot flatter, 17° latitude here so our panels face south with a 17° inclination so they are far less likely to catch the wind I'd be more worried about debris than wind catching them tbh. There's a few others on the forum who live more southern than me @Norwasian they would likely see more solar installs in their areas but rural NE where I am solar is almost as rare as hens teeth.

I'm actually about the same latitude as you, just farther west. In the mountainous areas here, solar is more common because the residents may not have access to a public utility. But the most common form is, like you mentioned, the small solar lights. Generators are far more common than solar systems. But there are a few solar systems.

I have not seen anyone trying to protect their panels. This is Thailand. In many cases, the panels were installed by someone other than the user--for example a charitable organization may have done the install on behalf of a school or village. The locals aren't sufficiently educated to maintain the system, and the system usually goes defunct within a couple or three years. If it breaks, it breaks: and that's that. People here are too ignorant to plan ahead, much less maintain something like a solar system.

 

[ThaiTaffy]

I'm actually about the same latitude as you, just farther west. In the mountainous areas here, solar is more common because the residents may not have access to a public utility. But the most common form is, like you mentioned, the small solar lights. Generators are far more common than solar systems. But there are a few solar systems.

I have not seen anyone trying to protect their panels. This is Thailand. In many cases, the panels were installed by someone other than the user--for example a charitable organization may have done the install on behalf of a school or village. The locals aren't sufficiently educated to maintain the system, and the system usually goes defunct within a couple or three years. If it breaks, it breaks: and that's that. People here are too ignorant to plan ahead, much less maintain something like a solar system.

Maintenance is non existent in any form as far as I can tell here, we recently looked at a second hand car where the air filter was the factory fitted one 8 years old, hence why I tend to prefer to learn how to maintain my own stuff.
Hoping OP does his research, not sure what the Philippines is like but I'm guessing he will likely have to do his own safety inspection and need to be able to maintain the system himself after the install.