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First, he used a prehistoric technology: he lit a wood fire.
But Prof Nordhaus also had a piece of hi-tech equipment with him - a Minolta light meter.
He burned 20lb (9kg) of wood, kept track of how long it burned for and carefully recorded the dim, flickering firelight with his meter.
Next, he bought a Roman oil lamp, fitted it with a wick, and filled it with cold-pressed sesame oil.
By 1900, one of Thomas Edison's carbon filament bulbs would provide you with 10 days of bright, continuous illumination, 100 times as bright as a candle, for the money you could earn with our 60-hour week of hard labour.
By 1920, that same week of labour would pay for more than five months' continuous light from tungsten filament bulbs.
By 1990, it was 10 years.
A couple of years after that, thanks to compact fluorescent bulbs, it was more than five times longer.
The labour that had once produced the equivalent of 54 minutes of quality light now produced 52 years.
And modern LED lights continue to get cheaper and cheaper.
Switch off a light bulb for an hour and you are saving illumination that would have cost our ancestors all week to create.
It would have taken Benjamin Franklin's contemporaries all afternoon.
But someone in a rich industrial economy today could earn the money to buy that illumination in a fraction of a second.
And of course our light bulbs are clean, safe and controllable - no flicker, pig fat stink or risk of fire.
The light bulb has become an icon of innovation.
It has transformed our society into one where we can work, read, sew or play whenever we want to, regardless of how dark the night has become.
But the price of light alone tells a fascinating story: it has fallen by a factor of 500,000, far faster than official inflation statistics suggest.
A thing that was once too precious to use is now too cheap to notice.