Lighting a major city at night can be expensive and leave a massive carbon footprint, so it's worth hearing out some ambitious alternative ideas about how to light up city streets in more environmentally-conscious ways. But China's Chengdu, one of the three most populous cities in western China, might take the cake for considering the wildest idea yet.
The city has recently endorsed a plan proposed by a private aerospace company to launch a large reflective satellite into orbit that can reflect a beam of light from the sun back to the city 24/7. The satellite would effectively act like an artificial moon that would flood the city with a "dusk-like glow" throughout the night, thus making streetlights obsolete, reports The Guardian.
Because a large amount of electricity in Chengdu is generated by coal-fired power plants, the plan certainly offers a carbon-neutral alternative. It's a take on solar energy not really considered before. Officials also claim that it will cut down costs of running and maintaining streetlights, but one would imagine that the cost of launching and maintaining a satellite in orbit would be expensive as well. So until a more detailed plan is released to the public, it's unclear whether the plan is truly financially viable.
Even so, it's a captivating, out-of-the-box proposal. The satellite itself would likely have solar panel-like wings with a super-reflective coating. Supposedly the illumination generated by the reflective surface would be about eight times what you would expect from the actual moon, and the light would have a dusk-like hue. Moreover, the beam of light would be carefully controlled so that it would only illuminate an area of 10-80 kilometers on the ground. So it wouldn't be visible to anyone outside the city limits.
Researchers also claim that the light wouldn't interfere with any nocturnal wildlife activities and will have a minimal ecological impact, although this remains to be seen. It's difficult to imagine how an unnatural nightly gleam wouldn't have some kind of impact on the behavior of animals, and even plants. Of course, so does artificial lighting.
Developers also believe that the fake moon could become a tourist attraction, drawing people from around the world to the unusual nightlife of Chengdu.
The plan hasn't been officially approved yet, but if it is, the satellite could be ready for launch by as early as 2020.
If it does take to orbit, the plan will not be completely without precedent. In 2013, the Norwegian town of Rjukan placed three large computer-controlled mirrors on the mountains surrounding the city to track the movement of the sun and reflect its rays down on the town square. Rjukan never sees the sun in the winter, due to shielding from the mountains that surround it.
Of course, placing mirrors on mountaintops and placing them in orbit are considerably different kinds of engineering feats, so it will be interesting to see if Chinese officials can pull off their plan. Perhaps by 2020, we'll find out.