Jack Frost has been visiting…..

3 06 2016

When I first moved into my apple packing shed, I said living in it would be character forming….. well I wasn’t wrong! Tasmania has been influenced by a strong high pressure system all week which, ironically, is going to send very bad weather to South East Queensland, among other places, on the big island up north. The resulting clear skies have given us a frost every morning this week, but today’s was something else….. I literally woke up to a frozen wonder world!

I now have a digital thermometer that tells me how cold it is outside my den (as well as how warm it is inside!) so I can plan how many layers to put on before I open the door…. if you have the technology, I say, use it!  And this morning in the shed, it was -2.5C, a whole degree colder than the previous best effort…. time to break out my down jacket….


Brrr… one frozen Fanny Farm!

Everything in the shed that wasn’t alcoholic was frozen… this is the time you put stuff in your fridge to make sure it doesn’t freeze! Seeing as I couldn’t do so much as make a cup of coffee in my primitive environment, I decided to throw the Nikon in the ute and go for a drive to check out my new frozen Geeveston…. but, having started the motor to warm things up a bit, I first had to get the ice off the windscreen, and it was a good 5 or 6mm thick!  Needless to say the wipers would not touch it, but luckily enough, because it was definitely not foresight on my part, I was frost2soaking a good dozen bottles of milk within which there was sufficient liquid water to put into the electric kettle, and pouring the warmed water over the windscreen did the trick. NEVER pour hot water on a frozen windscreen by the way….

To say the place looked magical certainly is an understatement, because everywhere I looked was like a fairy tale scene.

It certainly makes you think how on Earth the people who first lived here 150 years ago or


Yep, frozen solid…

more coped without the white man’s magic we now all take for granted.  It’s now well past 10am, and I can get water out of my kitchen tap again, so I can now wrap my hands around a hot cuppa…… though I better drink it fast before it’s too cold to drink!

Now I’m not complaining you understand.  I knew what I was getting myself in for, and I’m actually enjoying the challenges, not to mention the beauty of it all…. But I am looking forward all the same to Mon Abri MkII being built right now! Waking up to a warm AGA with the ability to make a hot drink when I please really appeals.


Yep, frozen solid too..!

The good news on that front is that the excavator is seemingly fixed, and that the digging will restart tomorrow. The sawmillers won’t start again until mid next week at the earliest, when all this cold weather is supposed to be over, for the time being, though it could rain again. Such is life.

Back in Queensland, my better half has bought a car. It’s a Suzuki Alto, the same vehicle I rented many moons ago when searching for land with Geoff on Bruny Island.  That car returned 3.75L/100km back then, and I’m not even convinced it was filled with premium fuel.  It was a bit of a bargain, at altofour years old and only 40,000km on the clock; it should be as good as new and easily last until the petrol runs out.  With only three cylinders, it’s also cheaper to register, making it, according to motoring data, the cheapest car to run in Australia…. who in their right mind would buy an expensive hybrid or EV when you can have an Alto?

I’ve also made a new purchase for the shed…. after persevering (struggling?) with the stupid and badly designed oven/cooktop purchased from Aldi off their catalogue sight unseen for eight months now. I simply got sick of fixing it and replaced it with an induction cooktop; which you better believe really came in handy this morning!

Resistance heaters, such as the one in the previous unit, take what seems like forever to warm up, especially when in the cold environment I’m currently dealing with.  The whole time you’re waiting for the heat, the stupid things draw the whole amount of power they are rated at, wasting every bit of it.

Induction cooktops on the other hand heat up the saucepan directly, and instantaneously. Plus you can dial in the temperature you want it to operate at, so when heating milk to make a hot chocolate, you can do this at 80 degrees, ensuring you don’t burn the milk. And when you remove the saucepan from the unit, it automatically turns off, having sensed there no longer is anything to heat! The impact on my power bills will take some time to analyse, so watch this space….



What it would take for the US to run on 100% renewable energy

11 06 2015

The internet never ceases to amaze me as a source of hopium.  This article on vox, Here’s what it would take for the US to run on 100% renewable energy, manages to knock the wind out of the techno-utopian belief that we could run Business as Usual with renewables, even though it totally misses the most important point about why it can’t be done…....

It sets the scene with:

It is technically and economically feasible to run the US economy entirely on renewable energy, and to do so by 2050. That is the conclusion of a new study in the journal Energy & Environmental Science, authored by Stanford scholar Mark Z. Jacobson and nine colleagues.

Jacobson is well-known for his ambitious and controversial work on renewable energy. In 2001 he published, with Mark A. Delucchi, a two-part paper (one, two) on “providing all global energy with wind, water, and solar power.” In 2013 he published a feasibility study on moving New York state entirely to renewables, and in 2014 he created a road map for California to do the same.

This road map looks like this:

jacobson-us-renewables-2015At least, this road map shows a decline in total energy use over the period to 2050, which is fine, we absolutely have to reduce energy consumption.  Except of course I think we need to do this by at least 90%, but who’s splitting hairs…?

The author, , then goes on to explain what is required to do this:

The core of the plan is to electrify everything, including sectors that currently run partially or entirely on liquid fossil fuels. That means shifting transportation, heating/cooling, and industry to run on electric power.

Electrifying everything produces an enormous drop in projected demand, since the energy-to-work conversion of electric motors is much more efficient than combustion motors, which lose a ton of energy to heat. So the amount of energy necessary to meet projected demand drops by a third just from the conversion. With some additional, relatively modest efficiency measures, total demand relative to BAU drops 39.3 percent. That’s a much lower target for WWS to meet.

Fine……. so far.

So how could the economy be electrified on this ambitious timeline? Brace yourself:

Heating, drying, and cooking in the residential and commercial sectors: by 2020, all new devices and machines are powered by electricity. …

Large-scale waterborne freight transport: by 2020–2025, all new ships are electrified and/or use electrolytic hydrogen, all new port operations are electrified, and port retro- electrification is well underway. …

Rail and bus transport: by 2025, all new trains and buses are electrified. …

Off-road transport, small-scale marine: by 2025 to 2030, all new production is electrified. …

Heavy-duty truck transport: by 2025 to 2030, all new vehicles are electrified or use electrolytic hydrogen. …

Light-duty on-road transport: by 2025–2030, all new vehicles are electrified. …

Short-haul aircraft: by 2035, all new small, short-range planes are battery- or electrolytic-hydrogen powered. …

Long-haul aircraft: by 2040, all remaining new aircraft are electrolytic cryogenic hydrogen … with electricity power for idling, taxiing, and internal power….

Electrolytic cryogenic hydrogen?  My eyes glazed over here……….

Here’s what the paper says:

Power plants: by 2020, no more construction of new coal, nuclear, natural gas, or biomass fired power plants; all new power plants built are WWS.

2020 is just FIVE YEARS away………  but who’s counting?

…to meet most energy demand with wind and solar, you have to radically overbuild electrical generation capacity. To wit: the authors estimate that total US energy demand in 2050 will average 2.6 terawatts. To produce that much energy, they propose building power plants with a total of 6.5 TW of capacity. By way of comparison, the US currently has about 1.2 TW of installed electric generation capacity, so this plan would involve expanding generation capacity fivefold in 35 years.

Here’s what that would require:

… 328,000 new onshore 5 MW wind turbines (providing 30.9% of U.S. energy for all purposes), 156,200 off-shore 5 MW wind turbines (19.1%), 46,480 50 MW new utility-scale solar-PV power plants (30.7%), 2,273 100 MW utility-scale CSP power plants (7.3%), 75.2 million 5 kW residential rooftop PV systems (3.98%), 2.75 million 100 kW commercial/government rooftop systems (3.2%), 208 100 MW geothermal plants (1.23%), 36,050 0.75 MW wave devices (0.37%), 8,800 1 MW tidal turbines (0.14%), and 3 new hydroelectric power plants (all in Alaska).

That will meet average demand. Then you need 1,364 additional new CSP plants and 9,380 50 MW solar-thermal collection systems (“for heat storage in soil”) “to produce peaking power, to account for additional loads due to losses in and out of storage, and to ensure reliability of the grid.”

Is that realistic? asks Roberts……

Uh, no says Roberts….. No it isn’t. The authors inadvertently give away the game:

We do not believe a technical or economic barrier exists to ramping up production of WWS technologies, as history suggests that rapid ramp-ups of production can occur given strong enough political will. For example during World War II, aircraft production increased from nearly zero to 330,000 over five years.

The phrase “given strong enough political will” is open-ended enough to allow virtually anything through. But what would create this political will, equal to what gripped the US in the wake of the Pearl Harbor attack? The authors don’t say much about it, other than a hopeful note at the end that their quantification of the benefits of such a transition “should reduce social and political barriers to implementing the roadmaps.”

But here’s the key thing for me.  exactly how would the US build an increasing quantity of renewables, growing year after year, while reducing fossil fuel use, year after year, at the same time..?  And we all know how much fossil energy it takes to build all those wind turbines…..

Something major would have to be abandoned.  Like maybe the US military?  After all, once the Arabs’ oil is no longer needed, it won’t need ‘defending’!  Dream on.  This is no Pearl Harbor.  This is civilisational change…..  and the only other time we’ve had change on this scale was when…..  fossil fuels were discovered and exploited!  I’m definitely not holding my breath, but you already knew this.

It’s AGA time again

3 06 2015

agabibleIt’s June, and Winter’s taken off with an early start.  No frosts yet, but it was 4 degrees this morning, and I was so glad to wake up to a warm AGA.  To top it off, my AGA Bible turned up in the mail this morning, and I’ve already picked out something nice to cook for Glenda when she arrives home again from Brisbane after a hard week at the office…… I mean University!

It’s full of clues on how to best achieve delicious results with a stove with no knobs.  Can’t wait to put it to the test.

If you’ve ever bought Asian food from a proper noodle bar with fairdinkum wok cookers, you will have seen a big hole with a raging fire covered with the wok for proper stir frying heat.  The boiling plate on an AGA is pretty hot, but it just doesn’t have the fire.  unless of course, it’s wood fired like ours!

I recently thought that if I removed the fuel filler plate in the middle of our boiling plate, my wok would fit nicely in the hole, and I could duplicate the noodle bar’s impressive fire cooker.

So tonight I harvested an onion, a chilli, a capsicum, and a good handful of Asian greens and coriander to go with last year’s garlic, turmeric, and ginger.  Tossed in some chicken, soy sauce, and honey from our hives, and voila, delicious honey soy chicken stir fry.  Serve with rice of course, or rice noodles….  Took all of five minutes to cook while I’m baching…….

I wonder if Amy Willcock will ever see my AGA fire pit…!


On a missed opportunity

26 11 2014

Maybe it’s my ingrained negativity, maybe it’s something else, but I have this irresistible compulsion to write this article; even though in many ways the house which is the subject of this post would at first glance appear to be a dream home, it just grates with me as a missed opportunity, and one that is growing as I think about it more and more.

My dear other half received an email from a friend who know the people selling this house in the Huon Valley, which is of course where we want to live.  The views are to die for, no doubt about that, and the house is a solar powered 8 star energy efficient one.  So why do I disapprove?  Read on…….

125 Swamp Road, Franklin, Tas 7113

The living space is just 70m².  I could live with that, if it had been cleverly designed.  But it isn’t.  You have to walk through the floorplan1kitchen from the bedroom to the [tiny tiny] bathroom and toilet….. which is flushing!  More about that later….  I really don’t like the kitchen, no space to work, let alone make cheese.  To heat it, they use a wood heater, when they could have had a wood cooker., that probably would save them on firewood in the long term, instead of using gas which we all know will become short soon, especially in Tasmania where all the gas comes from the big island up North….

The owners tell us that they don’t like walking on concrete, and thus have an above ground timber floor….  that almost certainly cost them the two more stars needed to make this the 10 star house it should have been.  Instead, they used this fandangled phase change thermal mass idea, which they put in the roof when it should have gone in the floor…..  sigh….  And what a missed opportunity for an earth bermed house, the site is perfect!

In the video linked below, the owner proudly announces that their 3.7kW solar array has all but ended their power bills.  Really?  Our 3.5kW system produces six to seven times what we need here, so where on Earth does all the power used in this tiny house occupied by just 2 people go…?  This is where the missed opportunities comes in.

First, the flushing toilet; all the waste from this house goes into an award winning Biolytix system.  This one, it appears, works fine, because it’s on steep well drained terrain with about five acres of grass below it to soak it all up, but the fact of the matter is, Biolytix went into receivership way back in January 2011 because nearly all the systems here in Queensland failed.  They cost between $10,000 and $12,000 to put in (probably more in Tasmania, as they came from Qld) and consume 44kWh per year, not a huge amount, but 44kWh more than our system here consumes!  Biolytix was founded by Dean Cameron in Maleny not far from here.  He’d already gone bust before with their Dowmus wet composting toilet arrangement, and you’d think he would have learned the error of his ways the first time.  Mixing water with shit is simply a bad idea, and to prove it, the very first house I designed for Glenda’s uncle and aunt in the Glasshouse Mountains has a Dowmus that still works because…… it has a dry pedestal sitting above it!  It may well be the only one still working, as far as I know.  Biolytix systems also cost some $400 a year in maintenance, at least in Qld.  I have no idea how much this might cost in Tassie.  Conclusion…….  they should have installed a dry composting toilet.

Where is all that solar energy going?  To start with, there is no solar hot water system.  I expect they have a heat pump, though if they have gas for cooking, they may also have a gas HWS.  Either way, it’s another missed opportunity, they could have done what we did and have a wood boosted solar heater and save on loads of PVs….

Then of course there are the two big iMacs in the study, which both use 170W (according to Apple) while our two laptops use a quarter of this consumption.  The conventional fridge in the kitchen would also consume some five times more power than our cool idea, and then there’s the huge TV in the lounge.  Beats me why anyone thinks they need such a large TV in a small lounge room like this house has…..

At 400 grand, it would be the most we could afford, and even then we’d probably have to go into a small debt unless they were prepared to come down….  having bought this admittedly great property – even though it’s steeper than I would like – we would have nothing left to rip out the kitchen and toilet, and switch to standalone power.  In the video, the owner happily states that they still have access to water in blackouts because of their header tank.

I’m almost tempted to describe this as a classic example of Jevons Paradox….

Is there anything I like?  Maybe I’m being overly pedantic;  it’s just that I’m not terribly inclined to move that far only to compromise on my list of essentials.  Going back to what I like, as I’ve already stated, the views are to die for (but they won’t feed you), I love the highland cattle, and the double glazed timber doors I would kill for.  There’s a lot of potential there……  but it would all cost money we simply won’t have.  If it were available as a blank slate, it would be marvellous, though I hate to think how much the driveway cost them….  and we still haven’t sold Mon Abri, though we have some seven parties that are very very interested, but who all have to sell their current abodes to win the race…!  It’s all happening, just in terribly slow motion.


Spiced Duck Breast with Orange and Fennel Salad

10 11 2014

It’s duck season.  This time of the year is always dry, and ducks go through huge amounts of water, at least for we who do not have a dam.  Whilst all that water is turned into liquid fertiliser by the birds, it is me who has to carry it back up the hill to water the veggies, and when you reach carrying capacity, it’s time to deal with the overpopulation.  So this weekend I killed four ducks; there are six more on their way to the Christmas dinner table, so not all is lost!

IMG_0241_1Furthermore, I have finally worked out how to pluck the darn things…  Duck feathers are way more tenacious than chicken feathers, and they are waterproof to boot, and then there’s all that down…..  To pluck a chicken, you have to dunk it in boiling water for a few seconds, and the feathers just fly off, easy peezy…  of course you have to be careful you don’t dunk the bird for too long, it can start cooking pretty quickly!  I even bought a plucking device (all the way from the Ukraine, would you believe…) off eBay, and whilst it works fine on chooks, ducks just thumb their beaks at this technology.  Then, I had a breakthrough…..

I decided that the water straight from the solar water heater was hot enough for the job, and 3/4 filled a 20L bucket straight from the bathtub tap.  Having dispatched the bird, I chucked it in the bucket, when something else happening distracted me, and I forgot about the bird for a good 10 to 15 minutes…..  by the time I realised what I’d done, the feathers were easy to pull out, especially with the duck plucker…  obviously it’s not the temperature that is critical, it’s the immersion time.  I can now kill a duck, pluck it, and dress it in just 30 minutes…..  a job that used to take me two hours, and put me right off slaughtering the poor things.

Once you’ve gone through that ordeal, you can concentrate on your culinary skills….  which is where the fun starts!  I recently made this great recipe almost entirely with what I grew here… the exceptions being the sugar (which I used sparingly), the olive oil, the spices, and the red wine and vinegar.


  • 2 tablespoons fennel seeds
  • 2 teaspoons cumin seeds
  • 2 teaspoons whole black peppercorns
  • 4 duck breasts (see note), skin scored
  • Juice of 4 oranges (to give about 300ml)
  • 3/4 cup (185ml) red wine
  • 2 tablespoons sherry vinegar or red wine vinegar
  • 1/3 cup (75g) caster sugar

Orange & fennel salad

  • 2 small fennel bulbs, trimmed, thinly sliced, fronds reserved
  • 3 oranges, peeled, sliced into thin rounds
  • 2 tablespoons sherry vinegar or red wine vinegar
  • 1/4 cup (60ml) extra virgin olive oil

IMG_0222First, separate your duck from its breasts with a paring knife.  You may notice the bright yellow colour of the fat and skin on the bird.  This is the result of free ranging and grass eating.  The remainder of the bird made two additional meals, nothing is wasted…


Spice Mix

Then place spices, peppercorns and 1 teaspoon salt in a frypan over low heat. Cook, stirring, for 1-2 minutes until it smells just great. Transfer to a mortar and pestle and crush to a fine powder.  it’s not often I get to use my wanky mortar and pestle, make the most of it… then rub onto the duck. Cover and chill for at least 1/2 hour.

Marinated Duck Breasts

Marinated Duck Breasts

Remove duck from fridge 30 minutes before cooking. Heat a frypan over medium heat. Cook duck, skin-side down, for 6 minutes or until fat has rendered and skin is crisp. Turn and cook for a further 2 minutes or until browned. Transfer to a plate and set aside.

Remove all but 1 tablespoon duck fat from the pan. Add orange juice, wine, vinegar, more fennel seeds and sugar. Bring to the boil, then reduce heat to medium-low and simmer for 15 minutes until reduced by half. Reduce heat to low, then return duck to the pan and cook, turning, for 5 minutes for medium-rare (duck is red meat… and if overcooked quickly gets tough, you’ve been warned..) or until cooked to your liking. Remove duck from the pan and rest, loosely covered with foil, for 5 minutes. Strain sauce, season and keep warm.

Meanwhile, for the salad, arrange fennel and orange on a plate. Whisk vinegar and oil together and season, then drizzle over salad. Scatter with fennel fronds

Slice the duck breast and serve with the warm sauce and salad.  All you vegetarian wusses don’t know what you’re missing out on..

Spiced Duck Breasts with Orange and Fennel Salad

Spiced Duck Breasts with Orange and Fennel Salad

Something fishy and the clairvoyant

16 05 2014

Steve Harrison

Steve Harrison

More from Steve the potter.. he never ceases to amaze me! I love his scrounging ways and how he makes things last, even his food…. the ultimate self sufficient potter…






I am at the fish market and see that filleted salmon frames are only $4. They appear to have a lot of meat still on them, so I decide to give it a try. It’s a big fish, or at least it was. It’s still a long frame.

Protein is the most expensive part of any meal for us. Good quality meat or fish costs upwards of $30 per kilo. Of course there are cheaper alternatives, but I refuse to eat sausages. I’m trying to limit my fat and salt intake and stay reasonably healthy, so I want to buy lean meat. Anyway, I only buy red meat once a month and I want to be able to feel good about what I’m eating when I do eat it.

Last month it was lamb shanks, cheap, flavoursome and when cooked slowly in red wine and reduced stock, the meat just falls off the bone and is quite delicious. I also buy chicken once a month as well. Some times its the whole bird. ‘The Lovely,’ skins it and boils it and from this she makes a great stock and the meat is separated and used for a number of meals. I’m not religious, so I also buy pork occasionally. Sometimes it’s the belly flap, boiled in our own cider and later, roasted to get that great crackling. This is a once a year treat. At other times I buy minced lean pork and we make gyoza, pork, garlic and vegetable dumplings, in the Japanese style. Sometimes pan fried in our own homemade stock or otherwise steamed.

For the most part though, we prefer fish as our major source of protein and we eat it 2 or 3 times a week, two days I fast and the other days we eat vegetarian directly from the vegetable garden, with or without tofu. I’m not a vegetarian, certainly not a vegan. I’m an omnivore, but within limits. For 35 years we kept ducks and chickens. They are such good company and a lot of fun to watch and interact with. We ate them on a regular basis. That is why we kept them. I feel that the only way in which I can justify eating meat is if I kill it myself. Only then do you realise the significance of what you are doing and fully appreciate the meal. I never found it easy. I always had to steal myself for the act. It’s all about living in reality. Taking responsibility for your actions. Being independent and self reliant.

I don’t wish harm on any other living thing in general. But I’m not a Buddhist either. I think that if I take responsibility for the meat that I eat then, I’ve earned the meal.

One of the cheapest fish at the market here is the local coastal Leather Jacket, usually at or around $5 to $9 per kilo. It’s a lovely fish, firm and tasty meat, but it can’t be filleted. It must be cooked whole, so people seem to avoid it. I love it. I have no trouble in steaming it or pan fry/steaming it. I really like it, but you can’t eat it all the time. The small local blackfish are also good value too. Always economical, as the fillets are too small for most peoples taste. I also like to buy sardines or garfish when they are in season and appear in the market. However they only appear intermittently.

So tonight it’s going to be ’empty’ salmon bone fish cakes. I simmer the frame for a while, leave it to cool and then separate the meat from the bones. The bones are then returned to the ‘soup’ and boiled again to make a stock. I plan to make fishcakes with our own potatoes and with a hint of wasabe fresh from the garden.

Now wasabe is an interesting vegetable/herb/condiment plant. It is supposed to only grow in the high clear environment of the Japanese mountains, washed by regular misty rain and growing in among the rocks and stones of fast flowing mountain streams, never allowed to dry out, always moist and well watered, growing in the shaded environment of the deep rocky ravines.

Here in Australia, there is a small producer in Tasmania, down south in the clear mountain environment where all the stringent conditions of cool dampness prevail. We once saw a small tray of fresh wasabe roots for sale in the green grocers. They had had a power failure and all the fridges and coolers were broken down over the weekend, so everything was on sale or being thrown out. We grabbed the tray of wasabe. Our initial thinking was the grate it up to make our own wasabe paste, and we did do this with part of it, but I thought, why don’t we give it a try in the garden, it’s already sprouting from it’s warm weekend spent wrapped in plastic on the tray.

We planted it out in our hot dry exposed summer garden, but we did give it some shade cover, by cutting bracken ferns and sticking them all around to create some dappled shade. We also gave it a disproportionate share of the cloudy dam water from the hose when we were watering. Now three years on we have a small tough little patch of wasabe permanently in the veggie patch. It couldn’t be farther from its home or desired environment, but it lives on, even if it isn’t thriving.

I get to make 10 good sized fish cakes from my efforts. We eat half for dinner leaving some for tomorrow. Served with garden vegetables, they go down a treat. Two main meals and two litres of stock for a risotto another day. All very good value for $4.


15 05 2014

I have been asked by several people now to write about the efficient use of firewood as an energy source.  I’m a firm believer that as we approach the looming mother of all energy crises, anyone thinking ahead of the pack should be seriously considering their options regarding the ways they will keep warm (especially in cool climates), make hot water, and cook.  I regard firewood as being one of the most serious options out there.  Solar is still the best, because the sun is free…. but unless you have gone to as much trouble as I have to design a lifestyle around solar, you will find the limitations of renewables pretty quickly.

ERoEIchartSo, why firewood?  Just look at the chart at left….  Firewood’s ERoEI is better than imported oil, wind, gas, nuclear, solar PV, and bio fuels.

Firewood is a renewable resource.  It grows on trees!  It’s more renewable than solar as far as I’m concerned…  However, demand for this fuel can outpace its ability to regenerate on local and regional level.  For example in some places in the world and throughout history, the demand has led to desertification.  Good forestry practices, and I’m talking about growing your own here, is essential to having your own sustainable source of energy.  Once in Tasmania, it’s my intention to replace any tree I cut down with several new seedlings to replenish the source and absorb the greenhouse emissions thus generated.  Not being able to grow firewood is my main reason for refusing to ever live in a suburban setting again.

Furthermore, if you grow the stuff yourself, you won’t need to pay for it (read work!) or move it very far.  Remember that once the oil supply shuts off, ringing up and ordering a truckload of firewood will be either impossible or unaffordable.  Always think ‘worst case scenario’.  If you live near a sawmill, there is every chance they will sell you scraps for peanuts.

Heating value of firewood

The moisture content of firewood determines how it burns and how much heat is released.  Unseasoned (green) wood moisture content varies by the species; green wood may weigh 70 to 100% more than seasoned wood due to water content.  Typically, seasoned (dry) wood has 20% to 25% moisture content.  It takes more than one year of drying time to achieve this, and depending on where you live, it could take two or even three years……  Not only does green wood release less heat, it also smokes, smells,  and gums up flueways in stoves and cookers, requiring more frequent flue sweeping.  I learned this the hard way!

The energy content of a measure of wood depends on the tree species, ranging from 4.75 to 9.8 GJ (Giga Joules) per m³.  To put that into context (because only an energy nut like me can visualise what a GJ is!), that much energy is equivalent to 1320kWh to 2820kWh, or about 2 to 4 months of your average wasteful Australian household electricity consumption. As you can see, the energy content of firewood is not to be sneered at….

The higher the moisture content, the more energy that must be used to evaporate (boil) the water in the wood before it will burn. Dry wood delivers more energy for heating than green wood of the same species.  It’s as simple as that.

Firewood energy efficiency

Now you have your firewood cut, split, and stacked, you don’t want to waste all the energy that went into this effort, let alone the energy in the wood itself.  Surprisingly, the first thing to consider has nothing to do with the wood….  is your house adequately insulated?  If all the heat your device generates simply goes out the window, you will have done a lot of work for little gain, even if you like watching fires burn…  therefore, first do whatever it takes to ensure your ceiling space is well insulated, that you have curtains and pelmets on your windows, and that your house is as draftproof as possible.  I know first hand it’s very hard to get an existing house improved, but anything you do will help, and save you money, effort, and firewood…

varied heat reflectors

Unfortunately, a lot of heat escapes straight up the flue.  The flue itself, however, can be the major source of space heating from your stove.  Heat reflectors that can be attached to flues to bounce heat back from the space near the wall (most stoves are installed in front of walls) and they also protect your wall from heat damage.

As most readers here would by now know, I am a great fan of AGA cookers because they are (as far as I know) the only ranges that inject cold air from the floor level into the flue to cool the flue down and reduce draft.  This ensures that much of the generated heat remains inside the cooker for as long as possible.

This works so well, our flue is rarely so hot that it will actually burn your skin on contact, something ‘ordinary’ heaters can do and anyone considering buying a stove should be aware of as a safety issue.  Even when ‘redlining’, the AGA’s flue is so cool where it exits the roof space, that one can (perched atop an eight foot step ladder!) put one’s hand on the flue and leave it there indefinitely…….  the best part of this is that we don’t even need ceiling exit protection to ensure the house won’t burn down!  Our flue simply goes straight out the cavity with just a few sheets of fibre board nailed to the studs for peace of mind.

My next AGA for the Tasmanian project will almost certainly be a fully recycled and overhauled four oven model, as I expect we will need a lot of younger hands to carry out the project and teach sustainability in return with loads of food to be cooked for the hungry hordes..!

4ovenagaThere are all sorts of clever devices on the market for burning wood, and this latest one really caught my eye..

Don’t discount the power of ‘sticks’….  we have fired pottery at over 1000ºC in a well insulated kiln using just 1 kg of scrap pine.  Pine burns much faster than hardwood and is great for achieving high temperatures very quickly.  I also use it to fire the AGA up and quickly get it to operating temperature whereupon I switch to hardwood for long burns and constant temperature.

I have never used rocket stoves – I think the bio-lite above may well be a version of one – but people I know who have swear by them.

They can be easily made from scrap material lying around or even turned into beautiful pieces of art such as the one at right.  Click on the photo and a great website about rocket stoves will be yours to peruse.

Also very efficient (but I have no idea of availability or cost in Australia) are so called scandinavian mass heaters.  After all, if ever there would be a people who know a thing or two about keeping warm, it’s the Scandinavians!

They rely on heavy thermal mass such as bricks or stones to store heat and can be very impressive looking to boot… though I don’t know how you’d build one inside your typical house without some major mods to the place! To me, they just look like a variation on the rocket stove theme, but having used the cast iron AGA, I can vouch for the usefulness of thermal mass or inertia in a stove.

Our latest wood burning addition is the cob oven which we will use in Summer when it’s too hot to fire up the AGA.  Apart from making pizzas in, we will use this oven like a regular one to roast meat and bake bread and cakes.

More of Alessandro's handiwork

More of Alessandro’s handiwork

In truth, your possibilities are only limited by your imagination and availability of the fuel.  The only rule to obey at all times is only burn aged firewood!  We don’t want to give firewood a bad name, and good luck….