We came across a time capsule when we were clearing out a spare room a few months ago: a ‘Solar Power Lab’ given by one family member to another nearly forty years ago and passed down through the family ever since.
Photovoltaic cells were cutting-edge technology back then. The cells in the kit – four of them, each about 5 x 1 cm, in a line along the back of the circuit board – were novel enough to be the selling point of an otherwise unremarkable electronics construction kit, and may well have accounted for half the cost of the kit.
The introduction to the manual, like the box, was all about the ‘space age’ technology used to power satellites – which were big news themselves in those days.
The ingenious recipient could construct any of twenty-odd projects, from logic gates (these were the days when home computers with 64KB of memory were considered powerful) to LED demonstration gadgets (LEDs were new, too) to transistor radios.
Moore’s Law was relatively new back then, too. I wonder how many people had any idea what its impact would be over the ensuing forty years? The purely quantitative differences have been so large that they have led to qualitative differences (from “big data” to the ubiquity of mobile phones.)
And solar power has grown almost beyond belief, too, on a similar path of dramatically falling costs and steadily improving efficiency. This ThinkProgress article presents a good overview of the current state of play, with one chart which sums it up beautifully:
Progress hasn’t been as rapid in solar power as in computing (Varun Sivaram explains why here, if you’re interested) but has been enough to overtake older technologies and to transform our future.
Once again, quantitative improvements have led to qualitative changes. Solar power is no longer a novelty and no longer a last resort for difficult situations such as satellites, but a realistic, cost-effective solution for all sorts of applications. Garden lights? Solar, of course – it saves wiring them in. Bore pumps? Solar, of course – no need to cart diesel down to the pump every few days. New suburbs? Solar with grid backup – not even vice versa. Parking meters? Lanterns for remote PNG villages? Traffic hazard warning signs? Domestic hot water systems? Solar, solar, solar.