Blank slate...

[Coconut]

Aloha y'all
TOTAL newbie here
This forum & Will's work is amazing!
Im building my home (300sq') on a coconut farm in Hawaii.
https://www.coconutinformation.com
Dream is to be off grid
Currently wiring walls up for a small fridge, few outlets, lights & fans.

Would you wire anything special (in prep for solar) while walls are open?
Just ordered Will's book & eventually will need to settle on a solar system
Simple = better (as I am brand new to this)

Any and all tips, ideas, pointers appreciated.

 

[prosper]

Personally if I were to go off grid, I would use 12 volt led lighting and have minimal use of 240 volt or 110 volt appliances. Hence, I would also install Extra Low Voltage cabling in the wall cavities, with ELV outlets, even cigarette lighter outlet if you like, you set the standards you prefer as it's a safer way to make use of electricity, especially if you're constructing a basic cabin. Yes, the cabling may be 4 mm2 but that's okay...

 

[b.james]

I agree with that . Run a few extra runs from the front to the back and bring down inside the walls and roll up . Keep a plan of where they are . I ran mine through under the ridgecapping one side to the other . House cable is not that expensive and you can use it for anything if its there . Good thinking 99.

 

[prosper]

Thanks for your message, its nice to know that you had thought out the extra cables needed as it would be difficult to install them after the wall claddings are in place. I was wondering how you can prevent rodent infestations in the wall cavities, maybe someone can recommend a benign or natural deterrent to place in the wall cavities. When I was assisting in building and construction many moons ago, the builder would place naphthalene balls in the wall cavities to deter insects and termites etc. It's not recommended now, though, as it's considered toxic. However, I've been breathing asbestos almost all my life, including having worked in the air-conditioning industry when asbestos was used in pipe lagging. I'm in my sixties now and still waiting for asbestosis or other lung diseases to occur. I really don't know why some people are subseptible but others seems okay. Still precautions should be considered when dealing with any substances. Thanks.

 

[Will Prowse]

Aloha y'all
TOTAL newbie here
This forum & Will's work is amazing!
Im building my home (300sq') on a coconut farm in Hawaii.
https://www.coconutinformation.com
Dream is to be off grid
Currently wiring walls up for a small fridge, few outlets, lights & fans.

Would you wire anything special (in prep for solar) while walls are open?
Just ordered Will's book & eventually will need to settle on a solar system
Simple = better (as I am brand new to this)

Any and all tips, ideas, pointers appreciated.

That is so cool!!! I love it!

Wow I am going to have to agree big time with Deno. That copper cost alone would be crazy at 12v. I cringe at the thought of that. 48v all the way, and use some point of use step down converters where 12v is needed.

I would actually wire it like a house with 110v, then run the whole thing with a massive inverter. Thats me though. I understand the reasons not to do that, such as efficiency. If it is pure offgrid, 48v probably ideal

 

[prosper]

Yes a 48 volt system is ideal. There is less 'copper losses' and a better use of existing available cable sizes. I mentioned lighting as I've wired up 12 volt lighting in places where mains voltage is unavailable. I wired up two 12 volt bulbs in each bedroom. Each 12 volt bulb is only 4 watts (380 lumen) which is adequate for general lighting. In total, there are 15 bulbs for the whole house, including the 3 bedrooms, kitchen, lounge and two external lighting. The 2 external bulbs are A60 with Edison 27 screw cap in weather resistant housing, the internal lightings are downlights in 12 volts GU 5.3. The voltage drop is negligible as I ran the cables in a ring circuit with resettable fuses in an approved enclosure. I might take some photos the next time I visit the premises. I had to use a 12 volt system as 48 volt bulbs are not freely available. I also had to wire up a 12 volt pressure pump and USB sockets for phone charging etc. I wired up separate 24 volt system for an inverter for their refrigerator. All in all, the lighting load is less than 100 watts, and the lights are not switched on all at once. I wired up the house with 2 core 4 mm2 cable that's more than adequate for the load. A 12 volt system is actually more than 12 volts as 12 volt deep cycle AGM batteries are utilized for the system. No earth conductor is necessary except for the inverter's internal circuit. I'm satisfied with the installation but would prefer to use a 48 volt system if I can obtain equipment that are designed for that voltage. Using DC to DC converter to buck the 48 volts can be feasible but there's more things to go wrong and reliability and efficiency will suffer. Also each of the converter will have to be installed as close to the equipment as possible, heat and insect infestions in the equipment in the ceiling cavity will then become a problem. Thanks

 

[prosper]

Thanks. For my ELV system, I use a ring circuit to reduce voltage drop, that is a two core cable with a size of four square mm cross sectional area connected in a ring circuit. Never had any problems with voltage drop or corrosion as some of these systems are already more than ten years old. I would prefer to use a 48 volt system but 48 volt inverters are more expensive than 24 volt inverters, as they're don't seem to be standard products. Many of my clients are economically disadvantaged, that's life, so I tend to do whatever makes sense to them, as its their final decision. I've tried using bulbs in parallel without much success, when one bulb fail, it's quite inconvenient to drag a ladder around to find out which one had failed. I suppose in a perfect World, things always work out as planned but in reality, it's very different. Perhaps in some of countries, electrical parts and systems are cheaper to acquire and install, while other countries, we experience a different situation.