We have just reached the half year mark in our ownership of our electric car. We chose the plug-in hybrid version of Hyundai’s Ioniq series of new electric vehicles.
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.
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.
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_
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.
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.
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.
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.
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.
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.
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.
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 >
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.
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.
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.
We are just home from spending the Easter Long-Weekend in Canberra at the National Folk Festival. 5 Days of great music, camping out under the stars, catching up with old friends and drinking some very nice pear cider.
Before setting of for home, I check the dash to see that we have a driving range of 111 kms, but home is 200 kms away, so I decide to buy some fuel.
As the days get shorter and the evenings cooler, we are lighting the wood fired kitchen stove most nights now. This old stove, that I have lovingly maintained and repaired for the past 40 or so years, cooks our food, heats our hot water, through its bronze firebox boiler, which is connected to our kitchen hot water system. It also heats the kitchen and us while we work, cook and eat.
In the hottest couple of months of summer, we cook on the gas stove and rely on the solar hot water panels to heat the hot water. We have had to cover the solar panels with wire mesh, as we had a pine cone drop onto one of them shattering the tempered glass.
It may seem strange that we have our solar panels on the ground. I have a good reason. We have a full copper hot water system, with a copper hotter tank, a bronze boiler in the stove and copper solar panels, all connected in series, so that either or both heat sources can heat the tank depending on the weather and time of year. I used all silver soldered copper piping to connect the system, so there isn’t a separate heat exchanger needed in the system to eliminate electrolysis. A full copper system has no electrolysis issues. Eliminating the heat exchanger makes the system much more efficient. I designed the system so that the solar panels are on the ground, so that the hot water will rise up into the tank by natural thermo-siphon. No pump is need in the system to circulate the hot water to the tank. (as is necessary when the panels are on the roof.) This is another added efficiency and saving on energy. By designing systems like this and others in our hand-made home, we have managed to reduce our energy usage in our home to 1.7 kW/hrs per day for the house alone. If we add in charging the electric car and firing the electric kiln from the solar system, then our total usage rises up to 5.7 kW/hrs per day.
When we add in our kiln and car, Janine and I still use only half of what a ‘normal’ single occupant household uses. Or just one-third of a ‘normal’ 2 person household. We are quite pleased with this outcome.
We share our last meal of stuffed Zucchini flowers. This time with a somewhat asian flavour profile, less cheese and more tofu. Ms. Kang feeds the chickens, we say our goodbyes and deliver her to the train station. There is a train service, more or less direct to the airport. We come home and start to shell todays harvest of hazelnuts. Just another day with so many jobs to do.
I spend a bit of time weeding and watering in the garden, then harvesting the endless procession of ripening tomatoes. Another batch of passata is on the way. I take the time to grab a handful of bouquet-garni from the garden along the way.
I finally get some free time to sort out my glaze tests from our recent glaze firing in the solar-fired, electric reduction kiln. They are all quite good, actually very good. These are all glazes made from my local stones, collected around the shire where I live. I’m very pleased with the latest version of my Kangaroo Blue glaze (see earlier post, Kangaroo Blue. 12/12/18) and the Bindook Porphyry pale limpid celadon. Not too bad for a 5 hour solar-powered firing.
Ms Kang has left the building. We’ll miss her.
Our international guest and pottery/environmental living intern, Ms Kang from Korea, is about to leave us. We spend our time in the pottery, garden and kitchen. We put in a big day from early morning through till late night, a 14 hour day. There is a lot to get done at this time of year.
We have glazed our pots and packed the kiln previously, so while we wait for the sun to get up in the sky so that we can start the firing. I get up on the roof and wash the solar panels. We live on a dirt road which is quite dusty in dry weather. We recently had a good rain storm and collected 75mm. (3″) of rain, but then we had 150mm. (6″) of wind and dust, This means that I need to wash the PV panels so that we achieve maximum efficiency. At this time of year, the shadow from the trees doesn’t pass off the last of the panels until 10.00am.
By 10.00am the sun is up in the sky and we are generating good energy, it’s a good time to switch on the electric kiln. I wait until the PV panels are generating enough power before I start the firing. I like to start about 10-ish and finish by 5-ish, thus making the most of the sun. The kiln is very powerful and can easily fire straight through to Stoneware 1300oC in 5 hours if needed. Once the kiln gets to 1000oC, I start reduction with 2 small pilot burners running at 5 kpa. I can’t set the pressure any lower than this and expect it to be reliable. This takes the kiln through to 1300 in reduction using just 300 grams of gas. I’m still experimenting with this kiln.
If we want to fire longer, or on cloudy days when there isn’t enough direct sunlight, we have the Tesla battery to fill the gap. We can, if needed, fire the kiln and charge the car as well on the same day. On a good sunny day, we can charge both car and Kiln, fill the battery and still sell a little to the grid. On the off days when we don’t fire or drive the car, we sell everything to the grid. We sell our excess at 20 cents per kW/hr. occasionally when it is cloudy for a few days we buy back power from the grid. We chose a 100% green power contract and pay the premium price of 35 cents per kW/hr for the privilege. However, we are connected to the grid by a net meter, so we only have to pay for power if our imports exceeds our exports in any given month. It never does.
Once the kiln is on, It fires itself in semi-automatic mode. I only need to check it occasionally. Then its back into the garden to continue the harvest of more tomatoes, chilis, capsicums and aubergines. We are at peak tomatoes now, as we dealt with the last of the late-season plums last week. They are all safely vacuumed sealed in their jars, in the pantry, waiting for later in the year.
While I harvest the tomatoes et al, in the vegetable garden, the ladies, Ms’s King & Kang collect hazel nuts and quinces from the orchard. We are all soon very busy in the kitchen, by the time the heat of the day sets in. All the tomatoes need to be washed and sorted. Even though we have set fruit fly traps all around our garden and orchards, we still get some fruit fly stings in the very ripe tomatoes in this late summer season of hot and damp weather. All the tomatoes are cut open, checked for fly strike and then sorted into two separate pans. A big boiler for the good fruit and a small sauce pan for the fly struck fruit. The spoilt tomatoes are all boiled to kill the grubs and then fed to the chickens, with the remaining skins and detritus composted or fed to the worms.
While I’m cooking, Ms Kang is shelling the days pick of hazelnuts. This batch of tomato passata will be cooked with pepper corns, bay leaves and a bottle of good red wine. It looks great and tastes delightfully sweet and sharp, sort of tangy, with just a little bite and lingering heat from a few chilli peppers in the mix.
The quinces are washed, peeled sliced and then boiled with a little sugar, 300g in the big boiler + a couple of litres of water to cover them. I add a stick of cinnamon, a few cloves and two star anise. After they have softened. I transfer them to baking trays, pouring the sweet boiling liqueur over them and add a little bit of Canadian maple syrup into the mix I give them 45 mins at 180 and this reduces the liquer to a sticky gel and turns the fruit to a lovely red colour. I choose to cook them with a minimum of sugar. If I added more sugar, they would turn a deeper/richer shade of claret red. I love that colour, but don’t like the saturated sweetness.
We preserve everything in our antique ‘Fowlers’ Preserving jars. We bought this old boiler and a few boxes of glass jars, 2nd hand at a garage sale over 40 years ago and they are still giving good service. We have only had to replace the rubber rings.
It still surprises me that a basket full of quince fruit can fill the sink when being washed, then fill 2 baking dishes in the cooking and finally be reduced to just 3 jars of concentrated sunlight, colour and flavour after a days work. Two baskets of tomatoes fills two boilers, then makes only 4 jars of passata once it has been reduced on the stove for an few hour.
Such is the business of summer.
We have a new intern working with us this January. Our visitor is Ms. Kang from Korea. She has come here to experience our sustainable approach to life and our ceramic work.
We have been working together crushing and grinding porcelain clay body and glazes from local rocks, throwing pots, working in the vegetable garden growing our food, cooking the food that we harvest and doing a little bit of sightseeing as well. The three of us have been doing some tourist activities together, like a trip to Sydney with a ferry ride on the harbour, and a trip to the local National Park and the south coast beaches.
Ms. Kang has been learning to use our foot-powered ‘Leach-style’ kick wheels. We have just finished making sufficient clay work today to fill the solar powered electric kiln for a bisque firing. Last week we calcined some local white granite rocks, to make our local blue celadon/guan glaze.
Pretty-much life as usual, but with a hard-working and dedicated student-guest.