It’s with a sense of fondness for you know, general naivety, which made our journey into the world of off grid solar derived electricity actually take place. How hard can this renewable energy technology stuff be? Turns out, like a lot of other things, it’s complicated and much depends upon, something or other. Way back in 2006 when peak oil was still discussed, the thought that the sun was in the sky, so there should be heaps of energy to nab, popped into the old brain. Where the thought came from, is lost to memory, but could have been due to reading and writing for the hippy press. Certainly back in those early days, details as to how the tech all worked, weren’t to be found in sales brochures, and forget about technical literature – that was non existent.
So, a little 80W Japanese made solar panel, purchased at enormous cost, was installed onto the roof of our little bush cabin, which was delightfully named: Jabba the hut! The heavy lead acid battery was equally financially ruinous, as were the wires, fuses, lights, inverter, television etc. You read that last item correctly. Much of the Star Trek Voyager series was watched on a small 12 Volt LCD flat screen. The rain may have been feral, the winds sure could howl, but the little wood heater kept the small space perfect for trips into the Delta quadrant .
Spoiler alert: The lost plucky Starfleet crew eventually made it back to Earth on the last episode. Was it a case of a: ‘and then I woke up conclusion’, because the series had been cancelled? And is the issue even worth thinking about?
Back then, so little electricity was required in the cabin, that I never really noticed whether the batteries filled up, or otherwise. There was that one time however, when presumably a Sulphur Crested Cockatoos bit clean through the solar power cable. Guess the big bird must have been attempting to sharpen it’s beak, or some other such stupid activity. Bet it hurt though! Have you ever applied the terminals of one of those small oblong 9V batteries to your tongue? I have. The large white parrot would have enjoyed a shock, but about a hundred times stronger! They’ve never done such things again…
Sorry, I digress. But it did serve the bird right. Anyway, with the solar panel disconnected, the first I knew of problems, was when the low battery voltage light was flashing. Easily fixed and there was gratitude that the parrot damaged cables had not shorted out on the metal roof. But other than that, the solar controller was basic and provided no daily data. Didn’t matter, we weren’t at the cabin very often. The batteries were full most the time, and who knew things would ever be any different? This tech is a total lark!
By 2009, we began building the house ourselves, and did all of the work other than the earthworks, house plumbing and mains electrical wiring. With the roof metal installed onto the house timber frame, we could add eight solar panels and wire them up to the big lead acid batteries. The plumbing and electrical tradies working on the dwelling, even used the solar electricity. Everything seemed OK. We moved into an unfinished house about September 2010 (Spring down here in the Southern Hemisphere). The power worked great, and being very busy getting the house finished, I barely took any notice of the power system – other than to observe that it was working.
By about April (mid Autumn) the following year, things were not all that rosy for electricity derived from the sun. Mild panic set in and a battery charger was connected up to a small 2KVA petrol generator. At least the power didn’t go out in the house. In those days, we used gas for cooking, plus the former wood heater had an oven and nifty stove top, so we didn’t really need a lot of electricity. I loved cooking with wood heat, it was the best, but alert readers will note the use of the word ‘former’, to describe the old wood heater, but hey, that’s another horror energy story.
Our solar future was ‘so bright I have to wear shades moment’ died that first winter. If the plants aren’t growing strongly, there ain’t a whole lot of electricity to harvest from the sun either. The photovoltaic panels work really well in summer, and they still do produce electricity in winter, but about only a quarter of the warmer time of year. To put the problem in it’s most simple and concise form, it’s the planets orbit around the star, dude! Near to the winter solstice, the days are short, and the sun hangs low in the sky. Not much anyone can do about that.
The response to the sad lack of winter solar derived electricity, was to add more panels. Sandra will happily remind me that in the early days, I used to make the naive claim that with just a few more solar panels, everything would work just fine, and we would ‘never have to think about it again’. It didn’t, and I don’t make such claims in these more enlightened days! From the original eight, we’ve added another forty! It’s worth mentioning that handling that much electricity reminds me what it must be like to ride a mechanical bull. It’s an exciting and ever so slightly terrifying experience. But over the years I’ve adapted the system to run cool at every single wire, connection and fuse. Experience taught me the need for that outcome, the hard way.
Over the years, a few arm-chair theorists have advised me that in order to optimise the solar power harvesting during winter, I should install a tracker which ensures that the panels face the sun dead-on all day long, where ever it may be in the sky. It’s one of those ideas, which sounds good in theory. The costs and engineering to operate what is essentially an extraordinarily heavy sail, and then delicately control it’s movement all day and every day in whatever weather, is completely off the charts nuts. It makes no economic sense. None! And every one of those machines at a home scale I’ve ever seen, were broken. It’s the wind load on the giant heavy sails – those systems just doesn’t work for very long.
A few weeks ago we added a further dozen panels to the system, which took the grand total to 48, and I’d forgotten to mention something interesting about the system itself. Everyone knows that the sun rises sort of around about the east, and sort of sets somewhere over in the west. Solar panels produce the most output when they face the sun dead on. It’d be nice to try and track the sun as it moves across the sky, and there is a cheap way to do that: by creating a virtual solar tracker. That is, a system can have solar panels facing all sorts of different directions, so as to at least get some solid electricity generation all day long. And that’s what we’ve done:
- As the sun rises in the east, there are 6 panels facing North East;
- 16 panels face dead North (and these do the heavy lifting);
- 20 panels face North West; and
- 6 panels face South West (and these capture the last of the sunlight as the sun sets in the west)
Does the arrangement work? Well 2pm today, which is late April (and so into the second half of Autumn) we harvested 103 Amps out of a potential 125 Amps. That’s pretty good.
There is no longer a wood oven here (sigh!), and we’ve seriously reduced our reliance on LPG (Liquefied Petroleum Gas) to an 8.5kg / 19 pound BBQ bottle every 37 days (at worst – during winter). The gas is used for boosting the hot water which is primarily heated by wood in winter, and solar hot water panels in summer. Haven’t worked out a way around that one, yet.
But for everything else in the house, we use wood for heating, and electricity for the rest.
We’re really trying to get this renewable energy technology to work, and it may, maybe… I read an article in the news the other day, that in some parts of the large city of Melbourne, people demanding this technology be installed due to environmental concerns, are discovering the limitations the environment will then impose upon them, and seem to be unhappy about the results. We’ve long known about this, and they could have all saved themselves a lot of hassle by having a quick chat and asking us whether we think that it’s all a good idea: Victorians transitioning from gas exacerbates growing problem of undervoltage.
I shouldn’t laugh, it’s a really serious issue, but if any area was going to vote for the left leaning Greens party, it’d be that part of the city. And the cynic in me does wonder whether this outcome is all a deliberate policy… Anywhoo, it’s probably due to the construction of the many new large multi-story apartment towers they’re building in that area. Those things require heaps of energy, and may not be as green as the locals would imagine.
As an old electronics geek from way back, the solar power system is a bit of a financially ruinous hobby, and why anyone else wants to jump onboard the journey, is something of an enduring mystery to me. There are some upsides, but plenty of downsides too. However, we’ve got the time and space to muck around with this stuff, most folks can’t simply bang in 16 used solar panels (picked up for $400), chuck ’em down in the paddock, and face them dead north. In the city the houses have unfortunately eaten all of the land, so there ain’t no space to do that. There’s just no easy ride with this stuff, and it’d be real nice, but sorry to say it, Star Trek dilithium crystals are pure fiction. What we’ve got as a civilisation, is probably as good as it gets, and when you’re at the top, there’s only one way to go.
The weather this past week (and the coming week) has been superb. Day after day of warm, sunny, calm autumn weather. A large high pressure system over the Tasman Sea has stalled, and we’re becalmed.
All that smoke produces some lovely sunsets:
With the new firewood shed almost completed, we began splitting and hauling seasoned firewood back up the hill.
We’ve begun filling the opposite side of the new firewood shed. Dry and well seasoned firewood is a beautiful thing.
Earlier in the week, the two large barn doors were attached to the new shed with heavy duty hinges.
It’s looking sharp.
Now the new firewood shed is nearing completion, the adjacent white cantina shed began looking like a poorer relative. This should not be!
We slapped a coat of woodland grey paint on the cantina shed, and gloss white on the two barn doors.
Then another coat of paint was applied to each:
A third coat of paint – yet to be done – should finish that work. Observant readers will note that the downhill side of the cantina shed, remains white. That side cops the worst of the winter weather, and so we’ve ordered a few sheets of grey corrugated zincalume steel to better weather protect it. Saves painting that side as well.
A lovely local lady gifted us a large bag of apples. Candidly, there were too many to eat, so we turned them into cider. We squished 2.7L / 0.71 Gallons of apple juice which with a bit of sugar water, exactly filled up a 5L demijohn.
In breaking produce news, the radishes planted in early March, are nearing ready to harvest. The leaves make a tasty pesto, and the bulbs are consumed grated in salads and enchiladas.
Despite the warmth last week, and this coming week, the lower sunlight levels determine when the many fruit trees go deciduous.
Onto the flowers:
The temperature outside now at about 11am is 14’C (57’F). So far for this year there has been 297.8mm (11.7 inches) which is up from last weeks total of 297.6mm (11.7 inches)
Leave a Reply