27 Kilns in 27 Days – vol 4

We get to spend a day in the Longquan Celadon Museum. I am travelling with my friends Len Smith and Robert Linigan. I am very interested in these old Celadon pots, particularly from my point of view of the inspiration that I can gain from the best pieces and equally importantly from what i can learn from the shards and broken sections. There is so much to glean from being able to see inside the clay body and looking at the interface between the body/glaze layers.

I love these rich and sensuous fatty celadons, guans and ‘ru’-like glazes. These are some of my favourite pots. It’s not too surprising that I like to try my hand a making glazes with this kind of influence. I wish that I could make something as good as this. It’s a quest.

In particular, I am keen to make my clay bodies and glazes as authentically as possible, by digging up all my own minerals, rocks and stones, then mixing them with ashes from my fireplace, where I burn the wood from my own forrest. It’s a complete commitment to my philosophy of self-reliance, not just in ceramics, but in my life. This coupled with a keen interest in the soft delicate beauty of ceramics the way I envision it. Not just the look, but also the feel of the surface. Equally important to me is the tactile impression -‘feel’ and balance of the pot in my hands, as well as how it will function when I eat or drink out of it.

My favourite coffee bowl at the moment, for my morning bowl of coffee, is a small white tenmoku bowl that is very translucent and very white, made from one of the Chinese sericite bodies that I have experimented with. It gives me a lot of pleasure just seeing it and handling it, even before I drink the coffee from it. It is beautifully balanced, only slightly weighted to the lower half for stability. It looks and feels gorgeous. I’m particularly fond of the slightly out-turned rim that is an essential quality of the tenmoku form. I’ve been using it for a year now and I’m still not bored with it.

Some of the unique qualities that I find I really engage with, are all its ‘faults’ – if that is what they are. I prefer to think of them as being part of its unique character. You can’t buy this bowl from Aldi on special for $2. Their white bowls may look superficially similar, but this pot has a story embedded in it that is only very slowly revealed over time as you get to know it.

For instance, because I’m not a very good potter, I don’t go to all the trouble of trying to make things perfect. Simply because I realised long ago that perfection only exists in the mind of the beholder, therefore can never be achieved, so why bother. Better to make things with character. This bowl for instance has a slightly mottled surface to the glaze, it has a very gentle undulation where the very thin clay body saturated during dipping and the glaze didn’t adhere perfectly. I have come to love this slight quirk of its appearance more than the very smooth glazed surfaces that I can sometimes make. This is a special part of this pots own history of its making.

Another point of interest for me is the hint of the remainder of the clay slurry on my hands left embedded in the surface of the clay after I finished throwing the pot on the wheel. I left it there as a reminder of the touch of my fingers. It is almost imperceptible, but it remains. I wasn’t aware of it presence initially, but it slowly became apparent to me as I got to use it, handle it and wash it up often. Not all my pots have this effect left in them, sometimes I wipe the inner surface clean with a fine textured sponge. At other times, I turn the inside of the pot with a trimming tool when I turn the foot. It all depends on how I am feeling about the pot as I make it. I never quite know how I am going to feel about what I make on the day. So its a surprise to me to be reunited with my own pots, post firing, and to re-discover their special qualities.

I can just see this swipe of my fingers in the image above. You won’t find that in a pressure cast or jigger-jollied bowl from IKEA.

This bowl also has a single iron spot in the glaze, just below the rim. It’s a bit like a beauty spot. I didn’t put it there, but I’m OK with it. This is a real object of beauty and interest. It isn’t perfect. It’s just gorgeous. It also shows my two stamp impressions. One is my initials, the other is the workshop stamp.

Finally there is the total lack of an obvious foot ring until you turn the bowl over and look underneath. I hid the foot recess inside the bowl form to minimise the weight, so as to keep this delicate bowl as light as is possible, but still have an elevated form that lifts it up off the table in a continuous elegant curved line. This is not true tenmoku form, but I think the it is better on this pot.

In the Longquan Museum we saw a lot of shards with loads chipped edges, shattered rims and broken bases. I loved this part of the display. It was all real. Many of the perfect examples had long ago been taken away to other larger collections, as this is only a smaller regional Museum. What was left in this Museum were all the other pots. I learnt a lot form looking inside the shards to see the very same qualities, problems and faults that I get in my work, using very similar materials and and almost identical techniques.

What I found particularly reassuring was that I am not alone. Someone else, 800 years ago also went through all these technical trials and difficulties to arrive in a similar place. Ultimately, there is the reward of the occasional lovely piece that survives.

This bowl is lovely, but what others probably don’t see, but I did, was what, at first glance, appears to the an incised line inside the bowl. That is easy to see, but it is in fact not an incised line, but a remnant of its making that appeared in the kiln during firing and wasn’t there when it was packed in the setting. It was formed in the fire. That wavy line is the raw glaze surface drying out and cracking slightly. The crack then doesn’t completely heal over when the glaze surface melts, but remains as a line in the glass. Perfectly fused, but hinting at its life before it became ceramic. I get it often in my glazed surfaces. It used to annoy the hell out of me, as there was no way that I could see to prevent it happening, if you fire long and low to make that particular satiny surface, it’s just what sometimes happens. If you fire hot, it disappears in the fluid melt at top temperature. This ‘scar’ is a relic of its process and making. I now look on these healed over cracks as an authentic product of the unique process that I indulge in.

Nothing is perfect. Nothing lasts. Nothing is ever finished, and that includes learning.

Kiln Disaster

Well, this is a bit of a sad tale. I have unpacked my latest kiln firing, only to find that 2 of my very expensive Japanese Silicon carbide kiln shelves had snapped during the firing and collapsed onto the work below.

Not a pretty sight.

The second and thord kiln shelves from the top have both broken.

Even though we lost 3 shelves worth of pots crushed or stuck together. There were still some very nice pieces to keep our spirits up.

The bottom shelf was OK.

Despite the disaster, there were still a lot of lovely pots that came out.

There is some nice subtle grey carbon inclusion and delicate ash deposit on the unglazed surface of the clay body.

The collapse seems to have diverted the flame path a little, causing some parts of the setting to get hotter than usual. This resulted in some over-firing and running of the glazes.

When the pale celadon glaze runs, it forms a very nice emerald green pool in the bottom of the pots. I really like the whiteness of the sericite body, contrasting with the emerald green pool and the pale hazey grey of the carbon inclusion on the rim.

I get out my quality control hammer and start to process some of the sub-prime pieces. They go into the ball mill, where they are polished for a few hours. When they come out, they are used as hand made celadon porcelain gravel ‘jewels’ for the driveway and paths.

This is one of the over-fired bowls below. The glaze has started to run, but it is still really beautiful. The runs have a build up of fine white ash glaze crystals. The pot has remained startlingly white, even with the wood ash attack. The glaze stopped just short of sticking to to the kiln shelf. What I find amazing, is that the sericite is so translucent at this higher temperature, that I can not only see light through it, but I can see the runs of glaze on the out side of the pot from the inside!

This doesn’t happen very often. It also has a beautiful, intense, emerald-green pool of celadon inside the base.

Its a really unique piece. You can even see the pink colour of my little finger holding the base of the pot on the other side, underneath. That is translucency! I’ll probably show it at Kerrie Lowe Gallery in November/December, in her Xmas exhibition.

I have kept one really translucent, but damaged bowl on the window sill in front of my wheel for inspiration. It’s ruined, the rim was destroyed when the kiln shelf on top fell on it and it is warped out of shape from the pyro-plastic deformation at the high temperature of 1300oC. Luckily, I was able to prize it off the bottom of the kiln shelf in one piece. It is so white and translucent, it’s an inspiration to me to see what is possible with this special ground up rock style of clay body called sericite.

I try not to think of the hours I spent working on it, turning and trimming it over several days, in various sessions, until I got it down to an even 2mm thick to get this result.

First Wood Kiln Firing since returning from China

I have just completed my first firing since I returned from China a month ago. I did a solar powered electric kiln bisque firing a couple of weeks ago and now this stoneware wood firing. I started very early at 4.00 am, simply because that is when I woke up. I usually do wake early on the day I’m due to fire the wood kiln. It’s somehow worked it’s way into my psyche. If I start early, it gives me plenty of time to get the firing done in one day.

I also really like the predawn time. It’s very quiet here. Mind you it’s always very quiet here most of the time, as we are one kilometre outside of a small village, with no shops or real activity much. We do have a road that runs right past our door, but there isn’t a lot of traffic along it. Our peak hour sees 20 cars and one bus go past. However, at 4 am there is no traffic, not even bird call. That comes later at dawn.

Dawn brings the silhouette of the huge pines that tower over our little school house building. The dawn chorus is beautiful, the firing is well under way and the front row of pots is illuminated by the flames.

I fire very discretely. By choosing to use a down draught fire box design kiln, I am able to fire without making very much smoke at all. If every thing goes according to plan, there is only the faintest pale grey haze during the reduction cycle of the firing, when most kilns make enormous quantities of smoke.

The chimney just pokes up through the roof line in the dead centre of this image. if you look very closely, you can just make out a pale grey haze, just to the right of the vertical light reflection on the camera lens. If you can’t make it out, it’s because it is so very pale.

I spent the day before hand, preparing and stacking all the wood for the firing. I’m trying mostly casuarina for this firing. I haven’t had enough of it at any one time to try it out for a full firing before. It wasn’t a very nice experience. I found that it produced quite a buildup of charcoal in the ash pit. I had to open all the mouse holes to get enough air into the base of the firebox to keep it under control. I won’t be using it again as the sole fuel source. I don’t have anything against charcoal. Actually, I really like it to build up to a certain level, as this creates beautiful surfaces on my fired work, but I need to be able to keep the level under control. Otherwise, It can build up to the point that it blocks up the firebox. Luckily, I had taken the precaution of also preparing some old very dry stringy bark and a bit of pine as well. That got me out of trouble.

This was a very good precautionary move. I always prepare more wood than I think that I will need. I nearly always have a fall back position, a plan ‘B’ as it were. It’s just the way I am. Perhaps just a little aspy? I even recommend doing just exactly this in my book on wood firing called ‘Laid Back Wood Firing’. Good to see that I even take my own advice!

Janine has picked fresh artichokes from the garden for lunch. She has steamed them and prepared a warm seasoned olive oil dipping sauce, with salt, pepper, garlic and chilli. It’s pretty yummy. She has thoughtfully prepared the dipping sauce in a twin-bowl bain-marie of hot water to keep the sauce hot on its 100 metre trip down from the house to the kiln shed, and throughout the meal.

We peel off the leaves one by one and pull them between our teeth to collect the fleshy, flavoursome pulp. It’s a great reward for our efforts to be able to eat gourmet food like this at virtually no cost. For us though, it’s not gourmet food, it’s ancient peasant food. Home grown, home cooked, consumed on site, within minutes of its picking, in its season, just as it should be. A meal like this has very low embedded energy and is SO delicious.

The kiln is at full fire. No one would know, except for the warmth being given off and the occasional crackle of the wood burning in the firebox.

While the kiln is firing, you can’t even tell that the kiln is alight for most of the time. I get to sit and write or do odd jobs, some cleaning up. It takes about 20 minutes in-between stokes, sometimes 40 mins, or even up to one hour when I stoke in a large piece of heavy hardwood. There is very little to do for a lot of the time.

I repaired an old kitchen chair that was given to us by the son of an ex-pupil of the school, That is pretty amazing when you consider that the school was built in 1893 and closed in the 1920’s. Jan Riphausen gave us his Mothers chair after she died and he was cleaning out her house. It has two broken spindles, but he thought that I might be the only person that he knew that might value old junk like this. Jan’s mother had lived almost next door to us here in the ‘Green Gate’ Farm, just down the road. The chair is quite ordinary, and was missing a couple of spindles. I repaired it with hazel water-shoots from our orchard. Not the most usual way to repair a chair, but a chair like this has no value these days except for the sentimental value it carries. I use it as my firing chair.

I like it a lot, because it is made with craftsmanship, from real wood. Therefore I can repair it, again with craftsmanship, using real wood. In this case, wood that I grew myself. The new spindles are not like the originals, they are quite uneven and ‘natural’. I love it for this very reason. Because it now has a very special personality. linked to us through the medium of the Old School building that is our home, but also because I have added myself into it now. A little bit of sabi-wabi. It’s like repairing a chipped, but beautiful pottery bowl with gold inlay. Kintsugi style. I have developed my own ‘kintsugi-like’ way of repairing my favourite pots. It’s not the ‘pure’ traditional Japanese technique. It’s my own way. It’s the way that I can do it using what I have around me. I’m not Japanese, but I can appreciate their culture. I really treasure being able to take something that everyone else would throw out, and spend a little bit of time and effort on it, and turn it into something very special, with real value. At least to me, and that is all that matters. I might hazard a guess that this chair must be pushing on for 100 years old. I can’t imagine any piece of Ikea, melamine-coated, woodpulp and glue, furniture being treasured like this in another 100 years. This is my life, reflecting all of the choices that I have made along the way, attempting to live a gentle, green, passive, life of minimal consumption. An existence based on creative endeavour.

So I’m sitting on my special ‘enhanced’ firing chair, contemplating the firing, listening, smelling, sensing the process. I play some music, I write, I even talk to the chickens when they come in to visit, and they come in often throughout the day.

This metal lid is now over 20 years old and is in need of a bit of TLC and a few repairs around the air inlets.

I get up every now and then and look into the firebox through the air inlet holes in the lid, Only then can I see the wood burning inside. If it needs it, I open the lid and drop in a few more logs. That’s it. It’s a simple process.

the level of the wood in the fire box has dropped down and it is ready to stoke again.

When the wood has burned down and the charcoal drops into the ash pit, I stoke it up and fill it with new logs. The bottom logs slowly burn away and the logs on top drop down to replace them, until it is time to stoke again. In this way the firebox is partially self-stoking.

The firebox topped-up with fresh wood.

This firing has gone very well, and after 12 and a half hours, when I look into the kiln through the spy hole, cone 10 has melted and this indicates to me that the full temperature has been reached. It is now time to sit and wait for the wood to burn away, so that I can slowly close down the firing and allow it to cool for two days. I celebrate with a glass of chilled white wine and a bowl full of freshly picked broad beans. This is a special springtime treat that I learnt to enjoy in Italy.

It is only now that it is all over, that it is clearly apparent that the kiln is actually alight, simply because I have opened all of the air inlet holes. 14 hours well spent, with still plenty of time to spare, just in case I might have needed it.

Because we choose to fire alone, we have developed a firing schedule that we can fit into one day. An early start, sometime around 4am, to 6 am. When ever I wake up. I don’t require an alarm. This allows up to an 18 or even a 20 hour firing without missing a nights sleep. 14 to 15 hours is just right. We have chosen not to do the longer types of firings that require more people to be involved and organising and changing of shifts throughout the night. 

This is meant to be a simple life, rich in experiences with just enough rewards for our efforts to make it worthwhile. 

I am reminded that, nothing lasts, nothing is perfect and nothing is ever finished.

27 Kilns in 27 days – vol 3

Vol. 3. Recent industrial wood fired celadon tunnel kiln.

While in the Longquan traditional celadon region researching celadon, we took some time out to visit a former celadon factory, that was forced to close when the economy was modernised. It has now re-opened as a celadon museum/cultural park.

I found it a bit shallow and lacking in depth. That is to say what was there didn’t grab me. It may be of interest to the more general tourist, but there wasn’t enough there to speak to me, as I’m interested in the more intricate details and technical information/insights that could be included, but weren’t.

However, there was an old wood fired tunnel kiln that had been restored. This kiln was the main means of firing the celadons here right up until 1998. One can understand why it went broke and couldn’t compete with more modern factories with up to date facilities and equipment.

There was also an clay processing section that used the old fashioned water-driven, wooden clay hammers, that is a technology that dates back 1000 years. It was exactly fitted with the age of the kiln technology, So out of date for a factory setting, it is hard to believe that it managed to last right up until the 1990’s.

Clearly, this equipment hasn’t been used for many years, possibly since 1998? Just like the kiln.

All the pots produced in the wood fired tunnel kiln, were packed in saggers to protect the ware from the fly ash from the wood fuel, which is so important when making a subtle glaze like celadon.

It is interesting to see that sometime between 60 and 20 or so years ago, they wrapped some parts of the wooden roof frame with ceramic fibre to stop it singeing or charring during firing.

The saggers that were used in the kiln firings are these days used as retaining walls and breeze way walls.

Vegan Wood Firing

It is a beautiful clear, sunny day here today. The air is cold and a little fragrant. I’m not too sure what with, but it is crisp and refreshing. We have been up to Sydney and back for the opening of the wood fired show, at Kerrie Lowe Gallery, where we have our work on show.

This is a small white tenmoku bowl with a lovely soft ash deposit on the fire face, showing grey some carbon inclusion on the body and rim.

A very delicate and beautiful object.

  

These are two of janine’s blossom vases. These two vessels are inspired by Korean ‘Moon’ jars. On this occasion, Janine has incised a sgrafitto, carved band illustrating the phases of the moon, as a way of linking these beautiful pots back to the origin of their inspiration in Korean, where we have spent a bit of time recently doing our research.

These pots were fired in just 4 hours in our small portable wood fired kiln. This little kiln is so environmentally friendly that I call this type of firing ‘Vegan Wood firing!

All the fuel for this kiln is collected from wind falls in our paddocks. Large old eucalypt trees are constantly dropping dead branches. We have to go around collecting these dead branches to keep the ground clear so that we can mow the dead grass. We have to mow, because in summer, high dead grass is a severe fire hazard. So part of out land management plan is to keep the ground around our house clear of fire hazards, as we live in a very bush fire prone area.

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Having picked up all these dead branches, it seems irresponsible not to use them productively. By firing our wood kiln with wind falls, we are not hurting the trees in any way. No tress were harmed in the making of these pots. Hence ‘Vegan Wood Firing’. As we only use what the tree has rejected and finished with. It is also worth noting that some of the carbon that we collected from the atmosphere through the trees that we have grown here over the past 40 or so years is now encased chemically in our pots, making it securely trapped, more or less forever. So we are doing our bit to reduce the carbon load in the atmosphere. Carbon sequestration and removal on a personal scale.

We each do what we can.

Winter Wood Firing Workshops

We are very busy all this month with our winter wood firing workshops. We run these every winter, and it has become a reliable part of our income. We will be doing 4 firing workshops this month. We are currently half way through the series. 2 down and 2 to go.

So far we have had some of the best workshops that we have ever held. Excellent results keeping the students very happy. AND a zero rate of losses so far. Pulling red hot pots from a kin at 1,000oC can be challenging. The clay has to be of the right kind and the firing just right. Fortunately, we have a stock the very fast firing and fuel efficient small portable wood kilns that we build in our kiln factory, on-site. We have a number of these at our disposal these days. They work remarkably well, they are a joy to work with. We take about an hour to fire them up to top temperature from cold for the first firing. The work is unloaded using metal tongs. All the participants must be wearing flame resistant clothes, such as woollen material and leather boots or shoes to take part. they must also be wearing long leather gloves when working around the kiln. The hot pots are placed in a bed of damp sawdust to reduce cool slowly. This reduced atmosphere within the saw dust bed causes the clay body to be reduced to charcoal black colour that gives the fired work a distinctive contrast look between the shiny coloured glazes and the matt black clay body.

3 to 4 of these little amazingly fuel efficient kilns are sufficient to fire the work of about 10 students, as the kilns cycle through the day. I have built a few different shapes and sizes , so that we have a taller chambered kiln and a wider setting kiln as well as a cubic  chambered kiln, we manage to get through all the different shaped work in the day.

The kilns are reloaded with new work and left to sit in the residual heat of the kiln for 5 to 10 minutes. This allows the barely warm pots a chance to assimilate the residual heat from the kiln structure, before we start to fire the kiln up again. The subsequent firings only take 30 minutes, as the kiln is already hot, usually around 400oC when the recommence stoking. There is usually just a few small embers left in the base of the fire box, just enough to rekindle the flame and get the kiln going again. As the day progresses, the residual heat in the kiln is increased and there are more retained embers in the fire box. It makes for a very intense series of firings and unpacking. As each kiln and its firing crew work at different speeds with different loads of varied ceramic objects, all the firings and unloadings become scattered in to a series of repetitive, rhythmic ins and outs.

The day ends with a period of pot washing and scrubbing to get the work clean and shiny before packing back into their wrappings, stacked back into their vehicles and heading home.

It’s a very busy day for us starting at dawn, wheeling out the kilns in to the open and getting them ready for firing, stacking wood into wheel barrows, setting up pyrometers, preparing kiln shelves and wads, collecting kindling and setting up the outside coffee and tea table with electric jug and urn, etc. Its intense, we are glad to be back inside by dark, with everything packed away safely and all the surrounding ground watered and raked over to make sure that there are no stray embers allowed to start to smoulder. After dinner and again before bed we make our way back down to the firing site to check for any thing that might have managed to evade our watering can.

Sunshine Came Softly Through My Spy Hole Today

This is the research paper that I presented to the recent Ceramics Triennial Conference in Hobart, Tasmania.  On the ‘Sustainability’ Panel.

Steve Harrison – Sunshine Came Softly Through My Spy-hole Today.

I was raised in the 50’s in a home where the topic of ‘health foods’ and ‘natural living’ was at the forefront of conversation. I came from a loosely quaker/buddhist background with a grounding in ‘healthy’ living. As a child, I was brought up in this environment. Aristotle said “give me the child until he his 7 and I will give you the man”. I am that man. A ‘greenie’ before the greens were invented.

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Since I decided to be a potter, I have always been a wood firer using a small, single chambered, bourry-box kiln. I wanted to fire my pots as cleanly as possible, in an environmentally sensitive way. In 1976 I moved to the country and bought a very old derelict school building, built in 1893, with seven acres of land and started planting a forest. By growing my own trees, these trees took their carbon out of the air, when I eventually burnt this timber to fire my kilns, it didn’t introduce any new carbon into the atmosphere. This was the best approach that I could think of to minimise my carbon footprint at that time.  I’ve progressed!

We have also planted very large vegetable garden and 5 small themed orchards, with a dozen cherry trees, a dozen almonds, a dozen hazel nuts, a dozen citrus, a dozen stone fruits, a dozen apples, 5 avocados, 4 truffle oaks, 3 white figs, two berry vines and a bower bird in a pear tree!

My wood fired kiln has proven to be very fuel efficient, I have worked on the design for over 40 years and written the standard text on the subject. ‘Laid Back Wood Firing’ and it is as clean as a wood fired kiln can probably get, without using an after-burner. I tried adding afterburners to several kilns, but have since abandoned that idea as too wasteful and complex. There is no point in using a premium fuel like LP gas to burn the smoke from an inefficient wood fired kiln. I couldn’t justify it. So I stopped working on that project.

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I did a lot of work on ‘flame tubes’. Fibre lined stainless steel tubes on top of the chimney that allows warm air in at the base, so that it mixes with the unburnt smokey fuel during reduction and combusts with-in the tube. All that is seen is a pale red glow at the top and bottom. The beauty of it is that it has no moving parts, and needs no external fuel source.  The blue haze at the beginning of firings has always bothered me and flame tubes don’t fix that problem. That is a work in progress.

It is possible to fire in reduction at high temperature with very little smoke, but the cold blue haze at the beginning of the firing is a very difficult problem to overcome. It was only later that I came to realise that it isn’t just blue haze smoke at the beginning of the firing when we are releasing ultra-fine particles into the atmosphere from our wood kilns. Wood firing generates loads of fine particulate matter, all through the firing. Some of these are quite fine and are hazardous to inhale. They are known variously as PM 7’s to PM 2.5 particles, they are small enough to enter deep into our airways and lungs and can cause all sorts of unpleasant health effects, even cancer.

Clearly, one kiln, fired intermittently, isn’t the problem, but when it is added to the other emissions of diesel vehicles, wood heaters and industrial pollution from factories, cement works etc. It adds to and is part of the larger problem.

See the EPA web site.   https://www.epa.sa.gov.au/environmental_info/air_quality/assistance_and_

advice/smoke_from_domestic_heating.

Added to this less-than-up-lifting scenario, there is the growing problem of global warming. Contrary to the statements of conservative politicians and the hard right media shock-jocks, the science IS settled and has been for a long time. The man-made global-warming deniers are simply wrong! They are either being disingenuous or choosing to be ignorant. Perhaps I could be generous and say that they are choosing different truths.

We used to be able to fire for 8 or 9 months of the year at home, but over the past 42 years, living in the Southern Highlands, our window of opportunity for wood firing has been reduced now down to 5 to 6 months, May to August. September is now getting too unreliable to book wood firing workshops. We have had to cancel workshops in the past few years due to hot, dry, windy weather and therefore total fire bans, as early as September. Total fire bans in our area used to only occur in January and February.

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Some time ago, I decided to develop a series of small portable wood fired kilns that could be wheeled out, packed and fired in one day. Then wheeled back away again until the next firing. These portable little wood kilns are very fuel efficient and can reach stoneware temperatures in 3 to 4 hours using a wheel barrow of wood. If you are careful, they can be fired very cleanly. They are a fun solution to minimising carbon emissions and avoiding the use of gas and coal. By collecting fallen branches from around our block, we can fire with a zero carbon foot print. This is the ‘vegan’ equivalent of wood firing . No trees were hurt to fire the kiln. The trees drop the dead branches. We have to pick them up to mow the long grass. We have to mow to reduce the fire hazard in summer. So fallen branches do not introduce any new carbon and are tree friendly. That’s nice, and the kilns are quick and fun to fire. But particulates are still a problem.

So where is all this leading? I realised that I needed to find another way to fire my work cleanly and efficiently into this uncertain, carbon constrained, globally warmed, future. The climate is changing, so we must change with it. Janine and I have had solar hot water for over 30 years and Solar Photo Voltaic panels on our roof, for the past 12 years. We installed 3,000 watts of Australian made, BP Solar, Photo Voltaic panels as soon as we could afford to do so in 2006/7.

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Our first solar panels, with the netted vegetable garden with small vineyard and orchard.

We have been using our electric kiln for all our bisque, earthenware and oxidised stoneware firings ever since then and have always paid the little extra for sustainable green power since it became available. So that if we needed to draw power from the grid, it was sustainably generated power that we used. In the last couple of years we have been working towards firing our work in the summer months of fire bans, using a new low-thermal-mass electric kiln that I built from a pile of spare parts, left over from my kiln building factory, after I retired. I designed and built a kiln that is fired using our solar panels and backed up by our Tesla Powerwall II battery.

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To allow us to fire in reduction, I made allowance to install 2 small pilot burners in the bottom of the kiln and built a small flue hole in the top. These burners aren’t used to fire the kiln at all. They are too small. The kiln fires to stoneware on solar power, the burners are only used to create a very small amount of flame to generate the reduction atmosphere needed to change the glaze colours.   I attach the burners to the kiln and light them when the kiln reaches 1,000oC. They use about 200 to 330 grams of gas to reduce the kiln load of pots steadily over a couple of hours while the electrical elements heat the kiln load of pots. It’s the best solution that I can find at the moment to give us reliable, all year round access to reduction firings that are very, very, low carbon and as sustainable as I can make them.

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The firing can take as little as 4 to 5 hours in total and give perfectly adequate reduced results. Experience with this kiln has shown that we can achieve all the normal reduced colours with our standard local milled rock glazes. I fire the pilots on 5 kpa gas pressure, but have recently experimented with pressure so low that the regulator gauge can’t register the flow and the kiln still reduces. We usually wait to start the firing until around 9 or 10 am, as that is when the sun is up high enough to give us the energy that we need to get the kiln going. It takes about 2 to 3 hours to get to 1000oC, then I attach the pilot burners and start reduction, around noon to 1 o’clock. I reduce for about 2 to 4 hours depending on what I’m experimenting with and finish the firing between 2 and 4 pm. as the sun is going down. We fire directly off the PV panels until 1 or 2 pm, then as the sun passes its peak, and the kiln is drawing its maximum power. The Tesla battery cuts in automatically to make up the short fall to finish the firing. If the weather is cloudy we can also draw down on our credit with the power utility. As we are on a ‘net’ metering system, and are always in credit. We never actually ever pay for any power that we withdraw from the grid. However, it is important to note that we pay the extra to contract to only use green power from sustainable sources when we do with-draw.

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I don’t know if you have ever seen one of these graphs?   It is the screen from the Tesla mobile app that tells me how much solar power I’m producing and consuming and/or selling/buying from the grid.The yellow area indicates the solar power generated. As you can see the solar energy starts off low at 7 am, then from 10.00 am it quickly rises to a peak at noon, hovers for a while, then drops away until 6 pm. and sunset.The green area is the energy required to re-charge the battery from its use since yesterdays sunset and running the house over night. This re-charging is usually complete by 9.00 or 10 am.The blue areas of tiny upward spikes is the fridge turning on and off regularly over night and all through the day. The sharp blue spike is the electric jug and toaster being used at breakfast time. On this day it was at 7.00 am. The white area below the line is the energy that we sell to the grid every day when we are not firing the kiln or charging the car. This generates a credit that we can draw down on in cloudy weather and covers our daily charges. This report tells me that I generated 35 kW/hrs of solar and used just 1.4 kW/hrs to run our home and pottery on that day. We sold 32.8 kW/hrs to the grid. It was obviously a quiet day with nothing much going on. I wasn’t welding in the kiln factory or ball milling rocks and pugging clay in the pottery.

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This is what a firing looks like, We simply stop selling our excess to the grid and use it our selves. The blue block is the amount of energy used to fire the kiln. The taller blue spike on the left, is the car being charged at the same time. It is worth noting that we can do both at the same time and still recharge the battery after wards in the afternoon.

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Just as an aside, we also have a solar powered electric car. A Hyundai, Ioniq, ‘plug-in’ electric car. I have written about this on my blog on a few occasions with regular up-dates to let readers know how it’s going. v< https://tonightmyfingerssmellofgarlic.com >

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This is what happens when we charge our car. We simply stop selling our excess to the grid for 2.5 hrs. There is enough power to do this, even on a cloudy day, as is the case in the chart above.

We put our pots out in the sun to dry. We call it the ‘solar drier’. The solar drier makes sure that the pots are totally dry before bisque firing. We can charge the car as well in the back ground, both using sunlight at the same time! It’s amazing that there is enough sunshine to go around! The vegetable garden keeps growing and the orchard thrives! We can also walk and chew gum at the same time.

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To help make this all happen, we recently bought into a community bulk purchase scheme and installed another 3,000 watts of Australian built solar PV from ‘Tindo’ in Adelaide. This allows us to run our house, fire our kiln and drive our car, all on our own sunshine. It’s a very nice feeling to be able to live, cook, work and drive, powered almost totally from our own solar power. We do all this and still have a little excess to sell to the grid. This covers our daily charges to be connected and even earns a little bit of extra cash. I haven’t paid an electricity bill for 12 years. You can see from our recent bill that we do all this and still use about half of what a single person household uses, and much less than half of what a two person household like ours uses.

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Now, I know that someone is going to ask me what is the cost benefit analysis? It’s the most common question that I get asked along with the statement, “I wouldn’t put solar power on yet. you can’t make any money out of it!”Well, my answer is, when you bought your new car. How did you make money out of that? Or, when you flew to Bali for a holiday, How did you make money out of that?

The point is that I did this because it pleased me. I get a lot of satisfaction out of it. I did it to extract myself as far as is possible out of the coal and oil economy. I didn’t do it for money. I do very few things in my life solely for the money. I’m not very interested in acquiring ‘things’. This is the equivalent of my holiday in Bali, or my ‘walking tour of the vineyards of Provence’. I’ve never been to Bali, or walked the vineyards of Provence. We each choose to spend our discretionary dollars in our own way. This is mine.

Now finally, I will add that I bought carbon credits to cover the carbon off-set of my flight here. Real off-sets in the form of planted trees. I buy a few hundred dollars worth of carbon credits each year to cover all the damaging things that I do to the environment in my life, like air travel. I think that it is worth it. I’m not proselytising for solar. You will have already made up your own mind about that. You’ve had a couple of decades to consider it. I’m just telling you what is possible, because you won’t have heard it from the the Federal Energy Minister or any one else in the government. This however, may be food for thought, if you haven’t already though about it. I will end by telling you that the future is here and this just might be what it could look like.