Lessons Learnt

The most important lesson is that with the right intention, it's possible to do anything include build an interesting house. If nothing else, the journey was worth the effort. And the result? Well I think the house is 'awesome'! And hey, it won an award for sustainability so it's not too shabby either.



Passive Heating
The very first lesson in the middle of winter was how warm the living room was. The sunlight flooded into the room as the patio roof had still not been installed and the floor sucked up this warmth. At night this radiated out as though the underfloor heating was on full bore.

The patio roof had always been a concern as its effect would be to block the light from the living room. After fully appreciating the importance of this heating effect, a redesign of the roof became a priority. I had always felt that the patio roof was too high (3.6m) and would it would not have created any sense of embrace or allure. As a result, we chose a rather unusual design that both allowed sunlight into the living room whilst dropping the height of the patio roof. This was fairly inspired and after it was installed completely satisfied our needs. The 45deg glass pitched section still allowed a significant footprint of sunlight into the house but lowered the roof by around one metre. The picture on the right was taken on Sept 26th, just after the equinox when the sunlight footprint was due to leave the the house. The house will now remain in the shadow cast by the roof (to reduce the heat load) until March 21, when the sun will again reenter the house to provide the passive heating we will again require. This has been so successful, we do not have an electric heater in the house. The average winter temperature was between 19-22 degrees and so far the average summer temperature has been between 21-26 degrees and we've had some hot days!


Biodigester
The biodigester does work in so far as it produces gas. It's also very combustible but there is a significant psychological barrier to using this as a replacement for existing cooking gas supplies. So at the moment I burn off some gas during a demonstration from time to time - but this really is a issue of boys with their toys. However, the intention is to compress the gas into a cylinder and then to burn it off for non-cooking purposes such as hot water heating or to use it in the hot house when that's finally up and running.

Grey Water Treatment
We constructed the water treatment bed and filled it with gravel, sand and then planted some plants. Shortly thereafter, we switched it on and my family and I went off for a two week break. The grey water then passed through the bed and was pumped into a holding tank that filled the toilet cisterns. By the time we returned, the house smelled like a sewer and the house sitter (Johan) was blamed for a variety of odours.

A greywater treatment plant is not a greywater treatment plant until you can build up sufficient microbial activity to process all the soaps and stuff in the water. It is, after all, a living filter and requires life to function. So after four months of promoting life and cleansing, the greywater treatment bed is now fully functional. The toilet cisterns are being filled 100% with recycled water and I've told no one in the house. The moment they hear this news, it'll be a matter of time before a psychosomatic smell appears in the house again.


Hot Water Solar
This is a great success. However not so when it's overcast. In fact, it would be safer to say that they do not work in overcast conditions - at all. But when the sun shines, they cook. Below is a plot of our electricity consumption for the geyser and lights only over a period of 4 days. The geyser draws 11 amps and is the block of consumption on the left of the graph during the first day. The three spikes are also the geyser getting a final bit of heating before the morning bathroom run during the subsequent days. The other little humps (less than 4 Amps or 1kW) are the cumulative consumption of all the lights in the house. Basically the one geyser element dwarfs the lighting electricity demand and when the sun shines, the sun completely eliminates this requirement. So I'm convinced they're worth the investment but we still have to get them to pass the hail test.

Roof Vegetation
This was a point of debate for quite sometime. In the end we planted some succulents on the basis that they would survive a dry spell. This was done after the topsoil was spread and initially this was our only roof cover. Then it rained and the grasses sprouted and the roof became a mottled green. In winter the grasses died back and the succulents came to fore once again. However even they were struggling just before the rains came this summer. They were seriously dehydrated so we intervened with some water. They have since made a great recovery and now that the rains have returned, the roof is again rich in green. But what's growing there is anyone's guess. I have a very apathetic view of this; whatever flourishes will and whatever won't will die. It's a bit like any ecosystem in the world.


The Garden
The worm farm is a great success. However the chickens have discovered them and the worms are now having to take some evasive action. The 'worm tea' is flowing abundantly. Not that it's all the worms doing. When it rains, the worm tea is literally leached out of the wormery and now I have a reservoir of the stuff.

The vegetables are growing well. Everything grows well in this area but I really don't have a clue about growing vegetables. Some things flourish then fail while others stumbled at first and then blossom. I do not have any idea what to expect except that when it begins to yield food, it comes in a massive tidal wave. I've even started buying books that instruct you on how to preserve food but I can't say they're a riveting read.

I raided the beehive the other day and ended up with around 2 litres of honey. I left the bees more honey than I took but at least it was a start. I've since invested in some more hives and I relocated a hive from a nearby estate into one of them. So I'm waiting on the second to become occupied and I hope this takes place soon. By next year, I should be off the honey grid.

I suppose the one lesson in all of this is that you don't just wake up one day and become food secure because that's your intention. It's a process of learning something completely new and the independence is something that takes months if not years to achieve.


The Chickens
They're a pain in the butt. They go on strike when they're put in the chicken tractor but cause chaos when they're not. The vegetables are taking a hammering and I have to ring fence each plant to save it from destruction - especially the broccoli and cauliflower. In the meantime they breed like rabbits but the chick mortality is high - not that we've seen a dead baby. I think the snakes are having a field day. The house has boycotted eating fertilised eggs as they have this 'white spot' which inevitably means the snakes are getting to eat more offspring. Not that I've seen a snake either. But we don't want to lock them up and when we forget to put them away at night, Rodney the rooster gives us the 4h30 alarm call outside our window. Rodney has nearly been turned to stew on several occasions now. This is a real love hate relationship and I'm often seen pursuing them around the garden like Mr Plod.