Outsourcing for electricity

Kyle and I are both having to learn a lot of new things to pursue this project. We quite enjoy that part, but there comes a point where we simply don't have time to learn everything we need to. One of the most significant areas was electrical wiring and solar panels. This is a big, sometimes complicated area that we knew very little about to start with (by very little I mean high school science level of understanding, enough to figure out where the cables need to go but not which parts to buy). The learning curve is not insurmountable, but the time it would take would mean there are other things we can't learn that we need to. Just like money, and building materials, and space, time is a resource we have to budget for.

So we're outsourcing for the electrical wiring. Not necessarily to a professional electrician (though we know we legally have to have one to do any 240V wiring), but to my Dad who has kindly offered to help. Dad had to learn all about solar panels and wiring when he built a motorhome a few years ago, which he and my Mum drove from Malaysia to Scotland and back (for real - go check it out). So he has a fair bit of experience with solar systems (though a bit smaller than the system we'll have), and how to repair them when something goes bung and you can't just drop down to the store for parts.

At some point we'll get Dad to do a guest post about it all, because we don't know very much about it yet (we're getting Dad to do it so we don't have to spend time learning just yet).

The arrival of the bags

We ordered our woven polypropelene tubing from the Bundaberg Bag Company, who were the only supplier we could find in Australia that would confidently sell us tubes instead of bags. A quick look through their facebook page shows someone from their end has been involved in a few international build projects - I'm not entirely sure, but the water tank they built in Vanuatu back in April looks a lot like the one featured in a "how to build an earthbag water tank" instructable I found a while back.

The tubing comes in two sizes, 460mm and 350mm. Rolls are 1000m long. I ran the maths as best I could, and I came up with 4x 30kL water tanks at just a smidge less than 1000m. That was cutting it a bit fine for my rough calculations, so we decided to get two rolls of the 460mm as it's best to do water tank walls tick. This way, we'll easily get 4 water tanks and have some left over for experimental practice and the lower levels of the house. We'll probably end up getting another roll of the narrower stuff for the house build, as the upper levels of the dome can be narrow and the lower levels wider, but that's later on.

All up, including delivery from Bundaberg to Canberra, it cost us around $1400. We messed around with the idea of having it all delivered to my parents place in Brisbane and getting them to bring it when they come, but it turned out not to be a huge difference in shipping costs.