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Jacques has been getting in the spirit of SFD 🙂

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Solar cooking event


The fastest solar oven to assemble is probably the windshield reflector variant as shown below. All one needs is a reflector, a black pot with lid, an oven bag  to act as a greenhouse and sunshine. It works and I have a blister to prove it.

While this setup is sure to satisfy the vegetarian’s appetite, one cannot fry or worse yet braai. There are however several lens (parabolic or Fresnel) designs at that address this shortcoming and include some pointers on heat retention mechanisms to permit cooking after dark.

Let’s have a sunny, solar cooking event and brainstorm our own solar braai – ideally portable – for the SA market. If you’re interested please contact Kina at or post a comment below. Remember ‘Two is a couple, three a H4H project’.

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Our geohash


In preparation for Software Freedom Day and the H4H stand here is the Geohash of the H4H address: kekhczvdbmvb. Geohashing converts a GPS location into a string. Latitude and longitude are expressed as two sequences of bits where each bit increases the precision by halving the interval a value falls into. For example, with latitude the first bit indicates whether a point is on the northern or southern hemisphere (90-0 or -90 to 0 degrees) the second whether the point falls into the (+/-) 90 to 45 or the 45 to 0 degrees range, etc.. The bit sequences are then merged into one sequence (even bits for longitude, odd bits for latitude) and finally converted to base32. There’s a worked example on Wikipedia.

Although short, a Geohash code is not a pleasure to type. One possible use other than to share it online is to generate a QR-code (Quick Response) for it as shown below.

Proudly generarted at – my very own, all Python QR code generator in a messy but working pre-alpha state. 🙂


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