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It works 24/7 with cover on and wifi off. It is not used as a room heater but computes 8 BOINC tasks with World Community Grid with all CPUs.
Temperature on the thermal images may not be precise as well as other numbers below is just a little experiment.
There are however set up options with the BOINC app to limit temperature to required levels. As well as number of CPUs involved in computation. BOINC app is really good with multiple set up option and is a pleasure to use.
According to the statistics from the WCG website, each WCG task takes approximately 15 hours. This means that this Android tab can compute 12+ tasks per day. Or about 4000+ tasks per year.
My average performance from all devices is 7 while I compute other projects including rosetta@home, einstein@home, TN-Grid, others.
Maybe I add more projects in future but for now this can calculates only WCG. Rosetta requires more memory.
I could not install a development version 7.16.03 of BOINC on this tab, it does work on 2 mobiles and an older tab, but here- not. So this is standard BOINC version from the Google play.
Both tab and mobile consume about 20 watts while active charging. Little less when about fully charged.
If fully charged, with monitor and wifi off, this tab eats 1.7 to 2.2 watt. Which means:
2.2 watt * 24 hours = 0.05 kWh per day
With 20 cents per kWh, this will cost less than 4 USD per year.