So, keep in mind that single photon sensors have been around for awhile, in the form of avalanche photodiodes and photomultiplier tubes. And avalanche photodiodes are pretty commonly used in LiDAR systems already.
The ones talked about in the article I linked collect about 50 points per square meter at a horizontal resolution of about 23 cm. Obviously that’s way worse than what’s presented in the phys.org article, but that’s also measuring from 3km away while covering an area of 700 square km per hour (because these systems are used for wide area terrain scanning from airplanes). With the way LiDAR works the system in the phys.org article could be scanning with a very narrow beam to get way more datapoints per square meter.
Now, this doesn’t mean that the system is useless crap or whatever. It could be that the superconducting nanowire sensor they’re using lets them measure the arrival time much more precisely than normal LiDAR systems, which would give them much better depth resolution. Or it could be that the sensor has much less noise (false photon detections) than the commonly used avalanche diodes. I didn’t read the actual paper, and honestly I don’t know enough about LiDAR and photon detectors to really be able to compare those stats.
But I do know enough to say that the range and single-photon capability of this system aren’t really the special parts of it, if it’s special at all.
You can host a webserver on a Raspberry Pi. I don’t know what you’re doing with your setup but you absolutely do not need hundreds of watts to serve a few hundred KB worth of static webpage or PDF file. This website is powered by a 30 watt solar panel attached to a car battery on some guy’s apartment balcony. As of writing its at 71% charge.
An Ampere Altra Max CPU has 128 ARM cores (the same architecture that a raspberry pi uses), with a 250 watt max TDP. That works out to about 2 watts per core. Each of those cores is more than enough to serve a little static webpage on its own, but in reality since a lot of these sites get less than 200 hits per day the power cost can be amortized over thousands of them, and the individual cores can go to sleep if there’s still not enough work to do. Go ahead and multiply that number by 4 for failover if you want, its still not a lot. (Not that the restaurant knows or cares about any of this, all this would be decided by a team of people at a massive IT company that the restaurant bought webpage hosting from).