Solar power has been going gangbusters since my previous post under this title (2014) and an update of it is well overdue. This isn’t it, however. What I want to do here is talk about domestic solar power, and specifically its advantages here in North Queensland, via four small projects which came out of our own move from one suburban Townsville house to another two years ago.
I will go from smallest to largest.
The new house is a low-set, 1950-ish cement block home pleasantly surrounded by trees. That makes it much darker than our old high-set home, and its double-fronted layout means that the central hallway gets no direct natural light at all.
We had to choose between running lights all day, every day, and putting in a small skylight. Initial quotes for a skylight (Solatube, basic model) were around $750 with, of course zero running costs for about 10 hrs/day of adequate light, 365 days/yr. Could we do better?
The internet and digital photography have opened up wonderful opportunities for ordinary people to get involved in citizen science as observers of the natural world. Online meeting places and forums come and go but the best at the moment seems to be iNaturalist – https://www.inaturalist.org.
It’s a global project and the numbers are huge: 54 million observations by 1.4 million observers from nearly every country in the world when I looked recently. That presents a management problem, of course, which is solved by having countries run independent branches, e.g. https://inaturalist.ala.org.au/
Anyone at all can browse the content of the site but people have to sign up to participate. When that’s done (at no cost and very little trouble) they can upload their observations, help with identifying others’ observations, and join the discussion forums. It’s a big and complex site but not too difficult to negotiate because it is exceptionally well planned and because there is no need to use most of its functions until you want to. (I have to admit there are some that I haven’t bothered with in the year I have been a member.)
And ordinary people can make very useful contributions to the project, especially if they (we) are outside the big cities.
Sitting at my computer a few days ago, I was distracted by a tiny bug moving around on the screen. My first impulse was to identify it, and the way it moved, its body shape and what I could guess of its leg-count all said, “spider, not insect.”
My next impulse was to remove it without harming it, and this is the point at which things got really interesting: I discovered that it wasn’t on the screen at all, but inside it. That, naturally (for me, at least) called for a photograph. Out came the camera and the macro lens …
But that was a problem, too, because photographing anything small, moving, poorly lit, obscured by its surroundings, or under glass is a challenge, and this was all five.
The rooftop PV system we installed seven years ago has just passed another good round number – 16 000 KWh – having produced 4 000 KWh since my last update, in September 2016.
The daily average in that period is therefore 5.9 KWh/day, a little lower than the average of the first five years. The drop in output is so small that it’s not really worth worrying about but three explanations come to mind, and all may have contributed to it:
We don’t bother cleaning the panels, so full-sun output may have dropped;
Our trees have kept on growing, so the panels may be shaded for longer, especially in winter;
The period we are considering includes two full Wet seasons but not quite two full Dry seasons (the month-by-month variation is shown here).
Townsville’s ongoing drought has encouraged many of us, especially the keen gardeners, to think seriously about bores, grey water systems and rainwater tanks. This post attempts to arrive at a credible answer to the first question we must ask about tanks: are they even useful?
We have been hearing from two schools of thought on the question for as long as we have been in Townsville, more than 25 years: “Yes, of course!” and “No! The dry season is so long and so dry that no tank will last through it.” One group must be wrong, and the only way to find out is to crunch a few numbers. Continue reading “Are rainwater tanks useful in Townsville?”