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A comment on New Zealand is about to test long-range wireless power transmission. Parent comment

Re:New Zealand is about to test long-range wireless power tr... by throwaway189262 on Wednesday September 09, 2020 @09:11PM (#24427870)
Will this disrupt other signals in the ISM band? If E2E efficiency is 60% there's maybe 30% radiating uncaptured? 400w is enough to jam anything else using the band for a long ways, maybe a kilometer?
[ Parent | on HN ]
Re:New Zealand is about to test long-range wireless power tr... by giantg2 on Wednesday September 09, 2020 @09:30PM (#24427972)
It could be that the radiating efficiency of the hardware is only 60%, ie lost to heat or in some other phenomena in the circuitry.

I'd imagine they'd never get approved blasting 400w per kW erratically.

[ Parent | on HN ]
Re:New Zealand is about to test long-range wireless power tr... by Emrod on Thursday September 10, 2020 @12:02AM (#24428774)
No "erratic blasting" intended :) this is NOT like a strong WiFi.

We are using a strictly point to point collimated beam that is expected to meet nothing but clear air. It shuts down if/when any transient object is about to enter the beam path.

Also, don't forget that the important figure you should be looking at is power density rather than total power

[ Parent | on HN ]
Re:New Zealand is about to test long-range wireless power tr... by TheSpiceIsLife on Thursday September 10, 2020 @06:40AM (#24430929)
> expected to meet nothing but clear air.

You also claimed it's unaffected by rain.

Which is it?

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Re:New Zealand is about to test long-range wireless power tr... by ourlordcaffeine on Thursday September 10, 2020 @08:01AM (#24431441)
He claims there is a laser safety screen that cuts the beam off if it is tripped.

Rain will trip the laser screen, as will fog.

Ergo, this will only work in clear air. Rain and fog will shut it down.

[ Parent | on HN ]
Re:New Zealand is about to test long-range wireless power tr... by TheSpiceIsLife on Thursday September 10, 2020 @02:57PM (#24435425)
In New Zealand, of all places, that's going to make this technology useless.
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Re:New Zealand is about to test long-range wireless power tr... by throwaway189262 on Wednesday September 09, 2020 @09:51PM (#24428114)
Yeah he replied elsewhere that capture is over 90% so maybe not problematic
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