Category Archives: Education

Electric Cars on Great Barrier Island

The way we get around can be an important part of day to day life, and any approach toward more sustainability and less environmental impact needs to address transport. Utilizing renewable energy sources (solar, wind and/or hydro) to power electric cars (E-Car) is certainly the right way – and although the technology is readily available commercially and constantly decreasing in cost – a traditional implementation on Great Barrier Island is just not cost effective. In the following an explanation of why it’s not feasible and suggestions.

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Vermiculture – Composting With Worms

A few months ago, I attended a free Island wide workshop on different composting methods. This course was funded by Auckland Council and was presented by Caity from Okiwi Passion, an organic market garden in the northern settlement of Great Barrier Island. The participants of that workshop could chose a free composting kit (worm farming, Zing Bokashi and kits for traditional cold composting). I opted for vermi-composting, a suitable addition to the other forms of composting that are taking place on BENIsLAND.

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Green Lipped Mussels – Great Barrier Island

Amongst the many delicious foods that you should try during your New Zealand holiday is of course a dish of fresh, big and juicy green lipped mussels. To make this experience more memorable, gather them yourself. Sometimes, you don’t even need to get wet to collect a feed of mussels.

Fresh, big, delicious and easy to prepare. Green lipped mussels.
Fresh, big and delicious green lipped mussels can be easy to gather and are easy to prepare as well.

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Endorsing and Subsidising Solar Power – New Zealand Must Do More

In January of this year I wrote an article about ‘long-term plans and incentives‘ after experiencing first hand the magnitude of already installed renewable energy systems throughout Germany within the private and public sector. Stating that the dimension and the extent of what Germany has been doing in this respect is incredible in this country is certainly no exaggeration. I was talking to a local board member about solar, wind and hydro power and whether there are any (comprehensive) plans from the Auckland Council and/or the Great Barrier Island Local Board regarding a pathway toward renewable energy sustainability for this Island (you may exchange ‘Island’ with whichever city you live in).

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Off Grid Power Systems III – Lead Acid Batteries

After discussing some properties of electricity and common methods to generate it, it is time to talk about how it can be stored. There are different types and designs of rechargeable batteries. This article is about deep cycle lead acid batteries. The principle difference between deep cycle lead acid batteries and those that are used in almost every car is the geometry of the electrodes. The former is designed to provide a small current over a long period (hours), while the latter to provide a large current for a short period (seconds). Continue reading Off Grid Power Systems III – Lead Acid Batteries

Off Grid Power Systems II – Generating Power

In part one I wrote about some practical properties of electricity and energy, in this part I write briefly about realistic ways of generating electricity for off grid home use.  Focusing on costs of setups and on quantifying how much power is generated. Part III will be about storing electricity, maintaining batteries, charge controllers and DC-AC inverters.

This is a comment I added to the previous post (Off Grid Power Systems I – Electricity):

  • To gain a better understanding of quantities like power, voltage, current, charge, etc., it is helpful to consider the analogy to flowing water.

There are basically five realistic ways to generate electricity: Continue reading Off Grid Power Systems II – Generating Power

Off Grid Power Systems I – Electricity

If you are interested in off grid power systems and/or already rely on them – as we all do more or less here on Great Barrier Island – you may ask: ‘How much do I need to know about things like photovoltaics, wind-power, batteries and electricity?’

The answers are straight-forward. You don’t need to know anything, a tradesman/-woman will sort you out and you can know as much as you want about these topics. It is 2013 folks, just type what you don’t know into a search engine and you will be presented with brief and exhaustive explanations.

My intention here is to provide you with a conceptual understanding – if you will a foundation or framework that allows you to build up further knowledge – and to also give you some rudimentary examples and calculations. I’m not an electrician and am also not in the business of providing off grid power solutions. My motivation is to share with you what I know and obviously also to continue learning via this process. Continue reading Off Grid Power Systems I – Electricity

I’m Not Going Into Detail

I got home quite late today after work, usually I’ll be in La-La-Land by now but instead I’m going to write this post. I went to a talk today about batteries – as you know there is no reticulated power here on the island and thus knowledge about off-grid power systems is somewhat vital – and when the highly experienced speaker mentioned at the beginning of his lecture that ‘he will not go into detail’ and that we, i.e. Great Barrier Island, have pioneered off-grid power systems, I felt a bit like being back at university. I hope I don’t get into trouble for posting this picture, but since I took a screen-shot of a very recent advertising campaign (which is online at the time I’m publishing this), I’d assume it is the same as providing a link.


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Nikau Palm

I’m somewhat fascinated by Nikau trees, an endemic palm tree to New Zealand; when allowed, they grow straight and tall, around 15-20 meters high, with massive fronds up to 3 m long. Their root system must be shallow as I can visibly shake a tree about 8 meters tall, which is probably around 30-40 years old. I found many clusters of nikau in the wet areas of my property and actually enjoy sitting there, amongst a forest of palms, in their shade and sheltered from the winds, listening to the birds and allowing my mind to wander. Their fruit is apparently edible, but I have yet to find ripe ones which I can also access. I’ve noticed Kereru (NZ endemic pigeon) and Kaka (NZ endemic parrot) eating the fruit and judging by the amount of juvenile nikau I suppose the bird life is doing well in regeneration dense clusters of nikau forests.

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Kererū, The New Zealand (Wood) Pigeon

The Kererū is allegedly in gradual decline and quite indeed an impressive pigeon, with its acrobatic twirls, noisy flight, beautiful colors and big size. Their conservation status is NT (nearly threatened), according to Wikipedia and other New Zealand sources. Due its large size it is one of the only birds that can digest and thus distribute large seeds and drupes. This explains why I have so many premature plum trees scattered all over the bush. They live in pairs and like to occupy the same area.

Beautiful and important New Zealand (wood) pigeon eating away on my trees.

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