New off the grid project in The Philippines looking for some advise.

[Jeroen Pasman]

Hello Everyone.
My name is Jeroen Pasman, I am new here on this forum. I am dutch and currently living in the Netherlands but ready to move to the Philippines and built my Off the grid house there. I have made a Facebook Page with all the info about the house that we are designing now and all that comes with it. So is the whole power supply and the solar off the grid system. I believe we are going to use a very minimal ammount of power but i like to do it right with some extra's for you knever know when.

So here is my idea for the setup :

For now i have the idea to use a 40 amp Controller, 24V max input voltage 150V at 24V max 1000 W .. i still need to see what kind of panels i can find there, but i can imagine 4 panels of 250 W at 35V , or 2 panels of 500W at 45 V. lets see whats available.

I want to limit the 230V devices as much as i can. We need to be able to power a small cooler/fridge. this is like a table model with 100 L cooling and 20 liter freezer. this kind of models will consume a 100kw a year. so this is 0.27kw a day. next to the cooler i need to be able to connect a laptop and aditional monitor. For now , we dont need more 230V devices. I will use a 24V 2000W inverter for this.

there 3 other diciplines that need power in the house. Lights , Fans and charger devices. I like to use this all on 12V. ist very easy to find LED light and Fans at 12V qnd als good usbC charge devices are avialable in 12V.

Now .. I want to run the whole solar power system on 24Volts. the Charger/ Controller and the Inverter need to be running on 24 V. The distibution of all my 12V needs will run on 24V and just before i need the 12V i will use step down devices to bring it back to 12V. This way i can use thinner cable and less voltage loss in longer lengths.

the 12V devices will be seperated in "groups"
I will have a living room light group of 20W 12V // a bedroom light group of 15w 12v // a bathroom toilet light group of 15W 12V // kitchen light group of 20W.
than the fans in the house take care of a decent airflow , 1 group for the toilet and shower at 15W 12V // 1 kitchen group at 20W 12 V and than the main system that will use 30W at 12V.
Offcouse this will not be used all at the same time. but the main air flow system will run constantly. (instead of an aircon).
All these 12V groups will be powered by a 24V cable and steepd down to 12Volt at the destination.

Last thing i need to add is that i want to add a storm wind turbine to the system as well. When the typhoons hit, i wont be able to catch some sunrays, but plenty of wind during these moments. This is something i need to look into and see what is a save way to do.

Now for me the mail question would be , how manny 24V batteries should i use with what amp and what type would you advise ?
I attached my drawings and ideas.
Please feel free to correct my drawings , advise me in any way.

Looking forward for your replies.

Jeroen.

 

[MichaelK]

Jeroen, how much time have you already spent staying in the Philippines? My wife is Malay, just a few hundred miles away, and I know what equatorial jungle heat is like. Are you really ready for a minimal power lifestyle without air-conditioning in a tropical jungle environment? Honestly, I think it's a bit naive to think you will be happy with "a very minimal amount of power".

My own personal experiences with life in another country is that getting replacement parts for anything that fails can become nightmarish. I have at least once found it was cheaper to fly back to the US to buy a replacement hard-drive for my computer, then it was to buy one locally. No, that wasn't BS. I did fly back. I think your best option is to standardize everything in the household for the local voltage/frequency, rather than try to do some kind of hybrid DC/AC system.

You might make it work at 24V, but I think in your case, 48V might be a better option. I'd get at least 2000-3000W of panels, not just 1000W. If your weather is like what I experienced, you will have lots of intermittent clouds each and every day, which will cut down on solar production substantially.

If you are anything like me, I really can't tolerate the nights in that kind of heat, and would need air-conditioning, at least in the bedroom to sleep. I would also get use to the idea of taking 3 showers per day to keep feeling human. Yeah, I'm a wuss that way.

I'd say with just a frig, TV, lights, and a computer, expect to use ~ 4kWh of power per day. Air-conditioning just one room and that bumps up past 10kWh/day. I'd expect to have at least 500Ah of battery for that.

 

[Bud Martin]

There are members here that live in the Philippines, you may want to contact them and get some suggestions.
Just type in 'Philippines' in the search.

 

[Jeroen Pasman]

Thank you Michael,
I have been in the Philippines twice , for 6 months and for 4 months. I love the heat and have no problem with that, this is one of the reasons i am leaving europe. I will deff not running any aircon. I do believe that a good controlled airflow will bring down the heat. It wil not cool it, but it will bring it down.
I agree on your idea of using more panels becouse of the clouds. this depends on the months offcouse. one of the reasons i want a wind turbine as backup.
the other reason that i am going back to an off the grid setup is tha i want to back to minimum. so no TV , no fancy things , just back to basic. this is what i like.

Bud , thank you for your tip. i will search on that.

 

[Greg P]

I agree with MichaelK you should build a larger simple system. Your needs may change in future and on rainy days you may need the extra panels to get a usable harvest. I live in Davao on Mindanao Island, When we remodeled out house earlier this year we installed a 5 Kw hybrid system with 48 volt 9600 watt battery. this is more than is actually needed to run our house approximately 205 sq/mt (2200 sq/ft). but I disconnect from grid during daylight hours and run the complete house off grid with up to 4 air cons running. The cost of your investment and ROI will not be that much more

I have owned this house since 1994 and it needed a few upgrades. As we were installing a complete new roofing system and went from 5 bedrooms to 3 some major demolition was done. So we raised all interior walls to 3 meter ( 10 ft) I believe this in addition to the reflective barrier placed under the metal roofing material made the house very comfortable. We can be comfortable with just fans, but I prefer to sleep with the air conditioning.
Good Luck