Rather than inverting 12V DC to 240V AC and back, you could skip a step and use a laptop car charger, converting 12V DC straight to ~20V DC.
You could also use a desktop with one of these ATX power supplies that runs on 12VDC instead of 120/240VAC:
How much load can be served from 1m² of sunlight
41–50 of 141 posts
Re: How much load can be served from 1m² of sunlight
#42I did this 20 years ago and ran the server for about 10 years. I down-scaled the server hardware when I transitioned to solar, but soon discovered that the low-power server just could not keep up with the demand. I upgraded to something in the middle that could handle a decent number of web users while still not using all the solar. I had 1280W of panels (16x80), a 1500W inverter, and three deep-cycle 12V 50AH batter…
Link is dead. So how much did the upgraded server draw?
Re: How much load can be served from 1m² of sunlight
#43I did this 20 years ago and ran the server for about 10 years. I down-scaled the server hardware when I transitioned to solar, but soon discovered that the low-power server just could not keep up with the demand. I upgraded to something in the middle that could handle a decent number of web users while still not using all the solar. I had 1280W of panels (16x80), a 1500W inverter, and three deep-cycle 12V 50AH batter…
Site seems down?
https://web.archive.org/web/20160401215358/http://www.jsl.co...
Re: How much load can be served from 1m² of sunlight
#44Are smartphones a good option here in terms of energy use?
Re: How much load can be served from 1m² of sunlight
#45What is the bottleneck is this system?
Theoretical: Amount of energy in sunlight.
Practical: The creativity of the engineer building it.
Re: How much load can be served from 1m² of sunlight
#46Is there a name for this effect in an abstract sense? I see it pop up a lot where the gains from scaling are super-linear to the scale itself. Or is it just called "economies of scale".
Re: How much load can be served from 1m² of sunlight
#47This is an aburdly bad result, mostly caused by the questionable 14W base power draw, but also due to the questionable choice of gzip compression, which is not exactly on the frontier of compression technology. Even zlib-deflate would decompress twice as fast at the same size ratios, but something like lz4 or snappy would be an order of magnitude less CPU time cost for similar compressed size.
The real way to have an energy-efficient service is to amortize away your idle usage and all of these inefficient conversion steps by just hosting your junk on App Engine.
Re: How much load can be served from 1m² of sunlight
#48I did this 20 years ago and ran the server for about 10 years. I down-scaled the server hardware when I transitioned to solar, but soon discovered that the low-power server just could not keep up with the demand. I upgraded to something in the middle that could handle a decent number of web users while still not using all the solar. I had 1280W of panels (16x80), a 1500W inverter, and three deep-cycle 12V 50AH batter…
Site seems down? https://web.archive.org/web/20160401215358/http://www.jsl.co...
Probably hugged a bit, it works for me.
Re: How much load can be served from 1m² of sunlight
#49Technically, it should be "200 watts". The losses happen due to all the inversion and conversion (I think... right?)
Re: How much load can be served from 1m² of sunlight
#50You won't get 200W from a 200W panel in direct sunlight, but it will still generate some watts at other times, so it should work out. "A 4.6b year old yellow dwarf as a light source" loved that
In power systems there is a number called the capacity factor that is used to relate the average actual output to the nameplate capacity over whatever time interval. In this article the author note that they are expecting 600Wh in a day, or about an average of 3h at nameplate capacity. That works out to a capacity factor of about 0.13, which sounds about right for a solar installation that wasn't purpose built in an area of high insolation.