Saturday, November 30, 2013

The tree that engulfed a fence

This tree slowly overgrew the fence that was alongside it.
Eventually the fence was cut away, leaving the metal fence posts and chain-link within the tree, which lives on.

Wednesday, November 06, 2013

Good, Clean Energy & the salt of the earth.

Have you noticed how most North Americans now concede that their contribution to climate change is real (and increasingly spectacular), yet have no access to clean energy?

At the modest end of the scale, installations of solar and/or wind energy remain prohibitively expensive for the average citizen. Some of the costs can be recovered by feeding unused energy back into the grid, but this entails more expense. Moreover, solar panels and wind turbines are not yet installed in quantities that allow for economies of scale.

On the large utility scale, only a handful of solar power generators supply electricity around the clock. Wind generator farms are typically connected to the grid, but contribute only a fraction of world electrical consumption. Hydro-electic power is well established  ̶  in areas where water supply and topography are favourable. Fuel cell electricity is highly specialised, costly and not available to the general public.

So, what can the rest of us do to experience the joy of clean energy? Well, some folks do it themselves, making and installing solar or wind power units. Some installations energize small devices such as laptop computers or lights, while others power up homes and recreational interests.

One website -, gives us an idea of the scale and variety of DIY generators . One of their smallest units makes use of old floppy drive motors while a more ambitious project supplements a homes's utility source with electricity from an array of collectors and rechargable batteries.

An ingenious supplementary source of hydroelectricity is found at Turlough Hill, Ireland, where a double-reservoir system pumps water to the upper dam. On demand it flows down again to the lower dam, generating power at peak consumption times.

On a larger scale, Gemasolar Concentrated Solar Power plant in Spain has achieved a round-the-clock power supply. Believe it or not, the key ingredient in its heat storage  is molten salt!