I have been musing on what it would mean to be self-sustainable on our property. I think, compared to our old suburban lifestyle, that we've made great strides in providing for ourselves. We still hook up to the utility, but our bills are a fraction of what others use on our island (we have the highest utility costs in the nation here on the Big Island) because we have a heat pump, photovoltaics, and solar water heating. We could do more by turning off everything all the time, but we do okay there. We are by no means able to chuck the electric company altogether - and the people we do know who have done so still buy gas to run generators, so that's not a solution. More solar might work, but we don't get much sun, frank, in a rainforest.
I could grow more, but with the exception of apples which don't grow prolifically here (although they do grow at higher altitudes) and which my kids adore, I could grow everything I buy in the way of produce (I shop the Farmer's Market pretty exclusively for veggies and fruits). This is an an area I could be more self-sustainable. Dry beans would need to be under some kind of rain cover - a very large greenhouse, but definitely doable. Black beans do well outside here, but soybeans and garbanzos would need some shelter.
Meat wouldn't be a problem, although I am not to that point.
I don't think we can grow wheat or, really, any grain. Sweet corn grows well in some areas, but not here - and the lack of sun would hinder corn for flour. I am going to give oats a try, but I have my doubts. Some wheat grew from undigested chicken scratch, but it didn't make it to maturity - much, much too wet, I suppose. I would be very sad without flour, so not self-sustaining there. I have thought about trying potato flour - potatoes grow here - but bread with only potato flour isn't so good. Or at least, I haven't found a recipe, yet.
Dairy is another thing that ends up in my basket when I do head for a store - I could fix that, if I had a dairy animal or two - but that's going to take some planning for fencing and housing and such. Not to mention time to milk and make the cheese/yogurt/butter.
I can't sew at all, and given my lack of fine motor skills, I doubt I could weave or spin, so clothing is NEVER going to be something I am self-sustainable with.
Ethanol fuel might be possible on a limited scale - engineer husband.
It's interesting to think about, but sometimes I feel like I am banging my head against the wall. For a variety of reasons, we're trying to produce more for ourselves, but it just seems to be so overwhelming, sometimes.