Passive & Off Grid. Yes, no, maybe?

Off Grid? Yes, no, maybe! It's so convenient to open a tap and water spurts out. It so convenient to open a hot tap and hot water spurts out. Conversely, it's really inconvenient when you open a tap and what you get is not what you expect.

Passive is really just a funky reference to using solar energy. It's as simple as that and no more. In fact solar is responsible for the winds, rivers and waterways too. So anything that uses hydro or wind or direct solar is just that: solar. And solar does not work so well when the sun does not shine. Or more directly, passive goes out the window when the sun does not shine: there is no passive heating, the solar panels are ineffective and there is no hot water. Simple. But when the sun does shine, it works a treat and that's probably 95% of the time. Human nature is such that when things are working fine, we take it all for granted - that's what we have been taught to expect. We're not grateful, it's just part of the service. And when things don't work just right, we're indignant, frustrated and even angry. Well if you plan to rely on passive energy and intend to be off grid, then your mood will definitely be defined by the weather and the moon phase may just make things worse. So be prepared and better still, change your habits and expectations well before you plan on providing your own services.

So just how big does it have to be for it to work? How many solar panels, how much water storage & how much habit change? Quite simply, if you don't want any habit change, then you're unlikely to have enough solar panels or water tanks. And even then, you'll be undone by the simplest of things. Take for example, our grey water tank that provides the water for all our toilets. Five hundred litres of water, which is enough for nearly 100 flushes. It gets refilled weekly and can last over a week but if one cistern has a slight leak, it won't last the night! 500 litres gone, just gone. The rain water storage of 30,000 litres which should be lasting us 6 months can be dusted in one month. This seems odd as we collect around two 500l tanks of grey water per week from all of our showers, basins and kitchen. Aaah, the vegetables! Take a hose to the vegetables and discover just how little water 30,000 litres really is. Add to that a dripping tap and your off grid dreams are down the plug hole. On the solar front, give yourself three days of continuous overcast weather and start considering the issues...the hot water's not so hot (in fact it's cold), the washing doesn't really dry that well and is backing up and the house is beginning to lose that comfortable temperature. Thankfully you still have electricity until of course the tumble drier is brought into play on the back of your geyser element. We don't have heaters (we have a very effective fireplace), but in a conventional house you'd need a whole new mortgage to install a solar array and battery bank large enough to deal with the combined assault of geyser elements, heaters and a tumble drier during an overcast spell.

Fortunately, one of the key requirements behind getting off grid was to be adaptable. This cannot be under-emphasised. We consistently fail to place sufficient value on the services our municipality provides us and in particular the endless supply of fresh water. Without this fairly basic service everything comes to an abrupt halt. Considering the value of this service, and now for the first time being able to appreciate its value, I'm surprised that every household does not have an emergency water reserve backed up by a borehole or rainwater harvesting. Absurdly we have insurance for all the expendable things in our lives but not this. One thing is for certain, in this house we can easily adapt to a very limited supply of water and I now know that it is in the adapting where the difficulty lies.

So you want to get off grid then? Easy. Go and camp in a remote spot for six months. One where there is no running water, sanitation, hair dryers, hot water, clean clothes, hair dryers and straighteners or fresh vegetables. Get your habits and expectations adapted first and then move into your off grid home. You'll then be grateful for all the luxuries that present themselves and will easily cope on those days when the sun does not shine. You'll also understand the value of water and that it's far more important than having light. You'll also understand the value of having a plan B since an off grid plan A is not as reliable as being plugged into a power station or a supermarket.

How to Boil a Frog

A bit of a technical update: PV solar operates at about a 10% output during heavily overcast weather! This was a bit of a surprise. Low power and cold water also present a problem. Do you commit your energy to heating the water and possibly have no lights or do you have a cold shower? What happens if it's a week of no sunshine? Two weeks? So many decisions, so few choices...

I was having my mandatory morning coffee the other day and got chatting to a solar supplier and it was the usual dialogue about the solar business and our choices. It's an interesting dynamic in that we would expect the major electricity increases to spur people to invest in energy saving devices - but it remains a trickle although the awareness is growing. Also there are issues with solar that don't really help, the main one being that it does not really provide an uninterrupted service - especially when the sun does not shine (like at night and when it's overcast). However, when we had the euphemistically named 'load shedding' there was a scramble for alternatives. It was then I realised that we're all frogs (in a manner of speaking).

Apparently (and I have not tried it) if you put a frog in cold water and bring the water to boil, the frog eventually overheats and dies. But if you drop a frog into hot water, it has a tendency to move fairly rapidly to escape the heat. The frog's behaviour is governed by the rate of change of his environment. When it changes rapidly and significantly, it responds appropriately but if the change is gradual (although equally significantly in the long term), the frog persists with trying to adapt to the change and eventually doesn't and then dies.

So despite today the fuel price and electricity prices have pushed new highs and are expected to do so well into the future, we continue to shrug off the heat and will try a bit harder.

It seems the Japanese have been suffering a long and drawn out deflationary period where every effort by their government to 'kick start' their economy has achieved nothing. It has resulted in a growing pile of debt for Japan but it also seems to be eroding domestic savings. If you take a look at a graph of Japanese savings over the past 20 years, it has been in gradual decline for some time and has almost reached the point where there are no longer any savings to mention. I can only speculate that this is an example of the cold water frog syndrome, where individuals dip into their savings on the basis that everything will to return to 'normal' tomorrow. As time progresses, the savings are reduced to the extent that any change they could have made is now very difficult or not possible at all.

Equally here in SA, had the government raised our electricity costs by 930% in one step instead of doing so over a ten year period (25% compounded over 10 years), we would have been hot water frogs instead of cold water ones. Had the same or something similar been done to the price of fuel, the double whammy would have had everyone focusing on and investing in a new lifestyle - which probably would have included low energy habits, smaller houses and very small cars called bicycles. Of course there would have been a huge adjustment, but that adjustment tsunami is coming regardless of the current or future pain and because it's happening so slowly, we ignore it. Unfortunately if we follow Japan's savings path, in ten years time very few people will have any savings at all and making the switch to a low energy lifestyle will become almost impossible. For everybody else, access to credit will also probably have evaporated so it amounts to the same net result.

For 20,000 years there was minuscule growth (and progress) and for all intents and purposes it was a flat line. In the last 100 years we've had exponential everything including appetites. For some reason we are convinced that the last 100 years is the norm and the previous 20,000 were the aberration. What if we are wrong? Can we as cold water frogs learn to behave differently? Perhaps at some point we'll recognise that we're in a pot on a burning stove and that warm fuzzy feeling needs some deeper consideration.

Off Grid Two Step

We're now off the electrical grid and have been for a couple of days. It was a bit of an anticlimax making the switchover. The lights still shone, the fridge and appliances still functioned and life went on as usual. There were no pipe bands, dancing girls or neon lights. In fact no one even noticed. But then we had an amazing electrical storm last night with gale force winds and a lightning display like no other and it seemed that we were one of the few houses in the area not using candles. Sweet.

I'm beginning to realise that being offgrid electrically is like driving a Prius. You keep looking at your consumption and trying to improve on your last 'record'. I find myself telling my kids when they're watching television that it's being powered by sunlight. Awesome. I'm also now switching off lights in empty rooms and the TV at the wall to remove it from standby. The computer's power function, which was completely ignored up until now has been configured to switch off the monitor after 10 minutes, the hard disks after 20 minutes and to euthanize it after half an hour of inactivity. This may be a sign that I’m a little obsessive but whatever it is, being off the electrical grid was step two.

Step one was to get off the water grid. We finally installed three 10,000 litre water tanks after quite a bit of deliberation. Not that there was any deliberation about getting off the water grid, but there was quite a bit of research on how to do it. I went to several companies trying to work out how best to store water and every time I was told that stored water goes "off". How on earth does H2O go off? Apparently it's not the H2O, it's all the organics that are suspended in the water that go off. Then I thought that I'd distil it all using some solar panels and even did the sums to work out how much energy is needed to boil and evaporate 500 litres of water per day. This process would simply remove all of the 'bits' in the water and I'd have perfectly clean and healthy water to drink - until I learned that distilled water is not fit for human consumption! Apparently it has no dissolved salts and if you drink it, it leeches all the salts out of your body. It's not an isotonic solution! It makes sense if you follow the logic so that option was also ruled out. Then I was told that rainwater is not that good for you anyway. How's that possible, we've been drinking it for thousands of years without any problems?!! Well it's the acid rain argument, but it had a new twist. It's full of pesticides. All those inorganic farmers spray their crops with poison and some of this remains suspended in the air and the rain washes it out. There really was no solution to this dilemma and it was becoming as confusing as cell phone contracts. There seemed to be an infinite number of reasons why every type of ‘natural’ water was not good for me and then of course why I needed to pass it through a whole lot of gadgets that cost fortunes of money to make it 'fitter' for human consumption.

I thought I would sterilise the water using a UV light. I'd already been informed about the myriad of bacteria that could possibly harm us and of course it's their cousins that make the water go off in the first place. So sterilising seemed the sensible thing to do and UV seemed the least intensive option. Finally I went in search of a UV supplier to be told by the first water treatment company I visited that a UV light does not work. It works a little, but not enough. Then I went to another water company and they said it works perfectly. Apparently they had installations where people were running river water through one of their units and it passed all the potable water tests. Obviously I would also need a filtration system which is a series of filters down to as little as one micron, which is very small. It was very confusing. All of this work to stop my water going 'off'. I even explored a reverse osmosis system. Now that's seriously high tech. It's also seriously energy intensive and expensive. Energy is an issue to me and we don't have an abundance of it being 'offgrid'. I now fully understand the meaning of ‘finite’ so that option died a rapid death. Then of course there's the Hydrogen Peroxide option, which is a popular industry solution to a lot of bacterial problems. It would also entitle us to free hair bleach with every shampoo. It doesn't repair split ends though, so we dispensed with that option. In the end, I decided to speak to someone in the know.

John, who works for me, lives in kaBokweni. He has a trickle of electricity and no water at all. He collected his water every morning from a filthy nearby stream and that's what they used to wash with. He'd take home five litres of water from time to time for drinking. However, he does have a solid house with a tin roof and we decided to install a rainwater harvesting system for him around 18 months ago. The tank was full throughout the rainy season and it almost carried him over the winter. In fact he was a few days away from making it through to the first rains the following summer. Since there was no-one else that harvests and stores rainwater in this neighbourhood, I asked him how 'off' his water was. Well it wasn't at all. He said it was crystal clear and tasted good throughout the year (despite the leaves that had fallen in his tank) and he confirmed that none of his family of five was suffering from any mysterious illness either. They all still had ten fingers and toes. His biggest problem was that all his neighbours wanted access to his water also.

Well that sealed it. I decided not to treat the water at all except for removing the visible bits from it. To do this, I put in a tiny pump that circulates the water through the smallest possible sand filter. All the harvested rainwater goes through this filter and every day for half an hour, it circulates the water in the storage tanks through the filter also. Obviously not all the water is filtered every day but it keeps it 'moving'. I don't know if this is too little or too much treatment, but in the end 'moving the water' is ultimately only a psychological cure to some psychological ailment that now exists my head insofar as storing water goes. If I've still got ten fingers and toes next year, then I'll know things are probably OK. If not, I'll have to make some changes.

Step three is getting off the food grid. Now that's a completely different ball game. All I know is that everything else will be easy in comparison so I'm not shredding my credit card just yet.

What would I Do Differently?

What would I do differently? I get asked this all the time and it is probably asked to establish whether there's an easier way to becoming more sustainable than the road I've taken. Not that I'm yet living sustainably but the gap is much smaller than it used to be. Also there is a lot to be learned and even more to be unlearned. So it's a journey and it's in progress.

The real question is 'what does sustainable mean'? Having gone down this road, there are many shades of sustainability often referred to as 'going green'. The most cynical type is really the 'greenwashing' of businesses or behaviours - the "PR Green". BP is a great example of this changing from British Petroleum to Beyond Petroleum with a nice green sun as its logo followed closely by being responsible for the largest oil spill in US history. Some things just are not sustainable and the way we’re currently exploiting the planet (and each other) falls nicely into that category.

Being sustainable today calls for urgent and meaningful changes in our expectations and behaviour. On a global level, technology will not save us. Technological progressions just increase our ability to outcompete our environment and are the antithesis of sustainability. When I began this process, I believed that globally we were capable of stepping back from the brink; that we could reason and rationalise and by doing so would come to the simple conclusion that we urgently need to make changes to our way of doing business and our capitalistic value system. However, now I’m not so sure. I’m beginning to believe that we have more in common with the reindeer of St. Matthew Island than I ever thought was possible.

On an individual level, building a 'green' house or 'passive house' is not the answer either. Such a house may be a step in the right direction. It'll help to reduce one's energy footprint by eliminating the need for vast amounts of heating, cooling, water, electricity etc. But while there is an expectation for all the luxuries of modern life, that position will never be truly sustainable. It is also almost impossible to change one's own lifestyle when all your peers do not see the same need for change, which is a euphemism for sacrifice. In changing, one occupies an isolated position. Generally, and it's a generalisation of course, we're conditioned to take the path of least resistance with maximum comforts (and making difficult changes towards sustainability is not on this path). In fact I'll go so far as to speculate that most people will be willing to exhaust all of their savings trying to maintain their current lifestyle and only when they've exhausted all options (like borrowing more), will they accept change as inevitable. Ironically at that point, they'll be least able to make the change. Unfortunately I believe this to be true of businesses, schools and society at large.

“The Last Hours of Ancient Sunlight” was a random pick of many books on the subject. “Plan C” by Pat Murphy was for me a better read and most recently there’s the “Post Carbon Reader” which gives an in-depth analysis on the subject. With a little bit of effort, it is easy to substantiate the message in these books. The message is quite simple: our economies (and hence lifestyles) are powered by fossil fuels and we are dangerously close to passing tipping points that will impose dramatic change upon us. It’s important to note that we will never run out of fossil fuels, we’ll just run out of our ability to pay for them (or the things they make). So the energy threat will never manifest itself as a shortage of energy but will always manifest itself as a financial one. In fact, there’s a large body of evidence that believes when energy costs exceed 5.5% of US GDP, it puts the US into a recession as illustrated in the graph. Whatever you believe, there is a direct link between the performance of an economy and the cost of it's energy inputs. So if you're going through a financial squeeze, then you’re probably on the road to Sustainability 101.

There are three major fossil fuel pillars in our daily lives: food, transport and household use. All of these are within our ability to control.

The average calorie of US food takes 10 calories of fossil fuel to produce and deliver to the consumer. In view of this, there is little wonder that in 2008 there were food riots in over 30 countries as the oil price spiralled up towards record highs. This was corrected by the Great Recession, which is now supposedly behind us. Today, again as the oil price goes through $100/barrel and food prices are hitting new record highs, food price triggered demonstrations are spreading throughout the Middle East – that region where globally we can least afford volatility as it has a direct effect on the price of oil. This could turn out to be a perfect example of a positive feedback loop. But what’s important to understand is that commercial food uses huge amounts of energy and the price of food is inextricably linked to the price of energy (fossil fuels). And in today’s society where very few of us grow our own food, we’ll just have to reach deeper into our pockets to feed our families.

We all know the cost of our personal transport. But is it possible to imagine a world without our ability to travel at will? What will you sacrifice to maintain your transport freedom - 200 channels of mindless television, mandatory holidays or designer labels? In our public transport starved country where private car ownership is entrenched, try climbing on a bus or into a taxi while your peers cruise in their airconditioned SUV’s and appreciate why this is a lonely road to take out of choice.

In South Africa our electricity costs are doubling every two and half years. So in two and a half years they’ll double and then two and a half years later double again. It's exponential growth at a rate well beyond likely increases in income. All of this energy goes into perfectly manageable lifestyle choices. So if you’re sitting with your salary cheque in your pocket and it fails to cover all the escalating costs in your life, you’re going to have to make some changes. And when you make this decision, it’s Sustainability 102.

So then, what have I learned and what would I do differently? I now know it’s possible to dramatically reduce the energy and water used in a house and I certainly don’t think it’s necessary to build a new house from scratch to do this. So the first thing I would do is not build a new house. If anything, I'd sell my existing house and move into a much smaller one and use the spare cash to make the following changes:

1. Replace every light in the house with low energy lights and preferably LED lights where feasible. This includes all outside security lights.
2. Replace the electric hob and stove with a complete gas unit
3. Retrofit a hot water solar panel to the EXISTING geyser and only use the element in the geyser as a last resort. Insulate all hot water pipes where quite a bit of heat escapes.
4. Heavily insulate the ceiling and ensure the roof is then well ventilated so that it does not continue to behave like an oven.
5. Plant deciduous trees on all east and west facing walls to protect them from direct sun in the summer. Remove all evergreen trees that block the sun from heating the house in the winter.
6. Learn to live without the many heating elements that are currently taken for granted: electric heaters, tumble drier (the sun works perfectly well), dishwashers & washing machines that heat the water (rather supply them hot water from the solar powered geyser) etc.
7. It’s prohibitively expensive to get off the electrical grid completely, especially if you don’t plan to make any lifestyle changes. If I were doing it again, I’d put in a much smaller electrical backup system and tie this into a deliberate lifestyle change. When you have no electricity, it’s a fairly compelling reason to change. So switching off unnecessary lights or the TV when no one is watching really will become a habit.
8. Transportation is where the change is hardest. Freedom of movement is well entrenched in our behaviours and society. You’re expected to drop you kids here, there and everywhere based on the functions at school or of their friends. The prevailing argument against our children walking or using bicycles is safety. There’s equally no appetite to create cycle or pedestrian lanes to change the status quo. It’s emotional blackmail and it works. So on this item, it’s really each to his own but the location of your house is very important.
   
9. Food is an interesting issue. It’s supposed to be possible to feed your family out of a vegetable garden the size of a front door. Ours is much bigger and we’re frankly very poor at it. Being organic in 'bug city' where there’s an orgy of growth of everything makes this fairly difficult. It’s much easier to grow veggies in the colder months. Nevertheless yields arrive in batches far greater than can be normally consumed. I’m now of the opinion that food independence can only be reasonably achieved by working within a small community where between the group, a reasonable diversity of products can be produced, preserved and shared. An improvement on this is Community Supported Agriculture where a community supports and shares the risk of a larger scale farming operation. It's as close as you can come to growing your own food without doing the growing. It also deals with the meat issue; urban dwellers prefer to believe that meat comes in vacuum packed parcels and this is one way to perpetuate the illusion. However when faced with killing your pet chicken or pet pig for the pot, vegetarianism becomes overwhelmingly appealing.
10. Finally, by installing low flow showers, not having any baths (jacuzzi or a swimming pool), we use very little potable water. We don’t have a meter, but we probably treat less than 150l of grey water per day for a family of four. Water independence at this rate of consumption is fairly easy to achieve considering the rains we’ve been getting lately and to achieve this you would also have to stop watering your roses.

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.

In - the end

Today the chickens produced their first egg. The cock discovered his crow a few days ago, so the one probably follows on from the other. It was small and perfect, but an egg nevertheless. That was after we had a lunch entirely from our vegetable garden, which was another first. On the whole, today has been a milestone but not quite as big as the past few weeks.

We moved in on the 27th of May and that was a milestone of note. The house was not quite ready, but we had to move out of our rented accommodation by the end of May and so we moved.

Johan and I had become experts in the just-in-time school of building. On the 26th of May, there were no functioning toilets - the biodigester had not arrived, but it did - at the 11th hour and that was my only real concern. I told my daughters that we would be using a pit toilet in the meantime but that was not well received. Seems toilets are incomplete without a mirror, basin and a variety of other essentials and anything less is just not funny.

Of course the rain did not let up until almost the last day. We started wet (the first rains) and ended wet and now that we're in, the clouds have vanished bar a couple of overcast days. The short overcast period taught us that solar hot water panels do not work well when there's no sun. But when there is sun, they cook! The underfloor heating is not really functional but not that it's needed. The temperature has plummeted to around 4degC but the house remains warm enough for displays of nudity - not that there's much of that with builders everywhere. But it's warm and the concept of passive heating works a treat. We've been out at various end of term functions and arriving back to a house radiating heat late at night is just fantastic. In the mornings, Johan who arrives wrapped up for arctic weather remains impressed by the residual warmth in the house. It's just great.

Molly and Dolly were an anniversary gift from Andrea who heeded some advice that we needed some sheep on the roof. Africa being what it is can breathe life even into the most eccentric of ideas. The sheep arrived and they were duly installed on the roof. They've got white bodies with black heads and stand fairly majestically at the highest corner of the roof casting their gaze over all visitors - most of whom who give a double or triple take. They're a truly African breed, made by the hands of some intrepid beadist who sells his wares at a local traffic light in Jo'burg. Being life-size, they're convincingly real - enough to stop the traffic. And they've witnessed every manic move that's been typical of the past month and most of all they love the Venda clay pots.

Jonathan and I worked together and he gave me a gift of an African pot some time ago - one made by Rebecca Matibe, a close relation. I ordered some more of these to gather my rainwater harvested water. The idea was that the water would seep off the roof and drain into these stunning pots before making its way to a collection point for treatment. It was a risk as I had no idea of the volume of water or how it would drain into the pots. There have been a few teething problems, but I've now installed a short chain from each downpipe to help guide the water without much spillage. Now they stand fairly proudly at the back of the house adding a very African feel to this earthy place.

These of course arrived as we were beginning to lay the paving and concrete panels around the house. I'm fairly keen to avoid a damp problem so we've paved and cast a 1.4m wide hard surface area all the way around the house. To break up the large entertainment area at the back of the house, we created a small labyrinth as a test of one's sobriety. If you can follow the curves, they will lead you to the front (back) door and it also makes a wonderful diversion for a stressed mind. At the moment, it's only the chickens that use it as they're the ones who can walk under all the patio furniture that now occupies the space.

The progress inside the house was fantastic. It felt like a marathon and included installing all the plumbing, the various cupboards, vanities, windows, alarm system and of course the painting, tiling etc. etc. The biggest shock in this regard is the cost of all the finishing - from the labour costs to the items themselves. It has been a sobering experience and I can now walk the labyrinth blindfolded. The significant increases in prices since our last renovation which was only a few years ago came as a surprise. Architects and builders talk of being able to do things cheaply, but this must come at significant compromises in quality - with just the cheapest of everything being installed which must create huge maintenance costs later. One of the sustainable movements' clarion calls is to invest in quality items - just for this reason. Gucci said it also when he claimed that 'quality is remembered long after the price is forgotten' - not that I carry a handbag and can testify to his quality. But it seems that quality is becoming less and less affordable and that a massive cycle of junk replacing junk lies ahead of us - until of course we can no longer afford the junk...

Of course poor workmanship remains prevalent and we encountered some more of that. Equally though, we had some fantastic experiences. The tilers, carpenters and stucco plasterers were fantastic. They were all self employed and did the work themselves. The biggest and most consistent problem seems to develop when a contractor drops off his semi skilled staff leaving them to their own devices. Despite the lack of supervision, lack of productivity and flared tempers, they seem unsympathetic. However, I suppose if your business is to make money off only your labourers' efforts and not your own, then having disgruntled clients must come with the territory.

We've still a bit to do around the outside of the house. The fencing is being installed at the moment and the underside of the roof slab is being plastered. The grass needs to be laid in front of the house and the patio roof needs to be installed. Fortunately the first patio roof design was rejected which meant that we moved in before it was installed. Now, understanding the importance of sunlight in the house, the design will radically change. The grey water treatment bed is still to be built and the rainwater harvesting tank needs to be installed. This will happen next week. Finally, the biodigester needs a gas line to be connected to it and then we'll be cooking off home made biogas.

So there remains a lot more to be said. But now I need to chase the chickens off the table and to prepare a place to eat my egg.

Fuzzy Warm

For a perfectly comfortable living space, we've installed underfloor heating & cooling. Our climate is fairly mild. It gets hot (30+deg C) and cold (5deg C), which is fairly temperate compared to Virginia for example, where you can add another 20deg to the temperature swing. A comfortable temperature for the whole year then is around 21 degrees, cool in the summer and warm in the winter. And that's where the underfloor heating & cooling comes in. This highly technical system that normally requires the input of engineers, architects and consultants actually only required a tiny bit of planning, a few coloured wax crayons and a sheet of polystyrene. And of course a few other pieces of polystyrene, pipes and connectors...

So the A-Z of our heating and cooling system is as follows (and donations are welcome): We insulated the floor of the house from the ground by laying 100mm layer of polystyrene down on the floor which had first been compacted, treated for termites and leveled with river sand. The polystyrene is what they put in into the floors of large fridges and freezers. Onto this we then laid our coils of piping which transfer the heat into or out of the slab. To ensure the heat is delivered to the correct room, we installed the delivery piping in the middle of the polystyrene effectively insulating it from the slab and the ground. When it reaches the relevant room, it is brought out of the polystyrene and that section is then cast between the polystyrene and the slab. The heat is then transmitted into or out of the slab.

Each room or zone has its own supply and all the zones share a couple of return pipes. The diameters of the supply and return pipes obviously differ, but it significantly reduces the amount of piping required.



Just to be different, heating is also provided in all of the cupboards. The theory behind this is to keep the cupboards permanently warm with ventilated air to prevent any mould build up. It's a problem here and I'm tired of mould growing everywhere while I sleep. These circuits are supplied separately to the rest of the circuits in the house.

The supply manifold is simplicity itself. There are no fancy solenoid valves with separate temperature controllers - another costly item to maintain or repair. We just have a simple system to regulate flow rate which when 'tuned' should provide just the right amount of heating and cooling to all the rooms in the house. This may take a bit of time to achieve, but it is not rocket science. And the picture is pre-manifold installation.

Currently we are busy with installing all the pipework, geysers, pumps and controllers in the 'control room'. The pumps are beautiful little things that can be set to different operating powers: 30, 60 or 90W. This is quite handy when you have different flow requirements and they are the same pumps that were supplied with the solar hot water panels.

Just to boost the heating in winter, I have ordered a slow combustion fireplace with a boiler attached. This will be connected into the system and the beauty of this is that we will be able to distribute the heat from the fireplace throughout the house. It supplements the solar heating, which is what we will be using to heat the water that will heat the house.

The benefit of the insulated floor extends to the hot water supply for all the bathrooms and kitchen. We have installed a ring supply which is also buried and insulated in the polystyrene. This allows us to circulate the hot water from time to time which has a significant water saving consequence. When you open a hot tap, the hot water will almost instantly arrive at the tap. This saves leaving the hot tap running while you wait for the water to arrive and in some houses that I've lived in, this can take ages and consume gallons of water. Being insulated in the polystyrene obviously saves significant amounts of heating energy. This means that the circulating pump need only operate for a minute or two every hour.

To cool the house, all we do is pump cool water through the pipe network. This should cool the floor down to around 15 degrees C which should make everything feel quite comfortable. The cool water is provided by a geothermal loop that has been buried outside - all 600m of it. Again this is free energy except for the circulating pump which uses next to no power even at full output. Nevertheless, considering the design of the house I expect that the heating and cooling needs will be minimal even at the worst of times.

So the only question that now remains is how well does all of this work? And that answer needs a bit of time and experience. But it will work.