Wireless power techniques mainly fall into two categories, near field and far-field. In near field or non-radiative techniques, power is transferred over short distances by magnetic fields using inductive coupling between coils of wire, or by electric fields using capacitive coupling between metal electrodes.[3][4][5][6] Inductive coupling is the most widely used wireless technology; its applications include charging handheld devices like phones and electric toothbrushes, RFID tags, induction cooking, and wirelessly charging or continuous wireless power transfer in implantable medical devices like artificial cardiac pacemakers, or electric vehicles.
... the current device can theoretically generate almost 4 watts per square meter, roughly one million times what the group's device generated and enough to help power machinery that is required to run at night.
By comparison, today's solar panels generate 100 to 200 watts per square meter.
## [Energy Harvesting](https://en.wikipedia.org/wiki/Energy_harvesting)
[Introduction to Vibration Energy Harvesting](https://www.nipslab.org/files/Cottone%20-%20Introduction%20to%20Vibration%20Energy%20Harvesting.pdf)
- [OVERCOMING IOT’S BATTERY BARRIER WITH SELF-POWERED SENSORS](https://www.iottechexpo.com/2018/11/iot/overcoming-iots-battery-barrier-with-self-powered-sensors/)
2019 [Internet of thingssparksrace to replace the battery](https://knowen-production.s3.amazonaws.com/uploads/attachment/file/3664/Internet%2Bof%2Bthings%2Bsparks%2Brace%2Bto%2Breplace%2Bthe%2Bbattery%2B_%2BFinancial%2BTimes.pdf)
> Era of mass sensors will require new sources of power
## review [RF rectifier for electromagnetic energy harvesting](https://knowen-production.s3.amazonaws.com/uploads/attachment/file/3669/Radio-FrequencyRectifierforElectromagneticEnergyHarvestingDevelopmentPathandFutureOutlook.pdf)
- [Converting Wi-Fi signals to electricity with new 2-D materials](http://news.mit.edu/2019/converting-wi-fi-signals-electricity-0128)
> Device made from flexible, inexpensive materials could power large-area electronics, wearables, medical devices, and more
2019 [Two-dimensional MoS2-enabled flexible rectennafor Wi-Fi-band wireless energy harvesting](https://knowen-production.s3.amazonaws.com/uploads/attachment/file/3887/zhang2019%2BMIT%2Btomas.pdf)
## [Wireless power transfer](https://en.wikipedia.org/wiki/Wireless_power_transfer)
> Wireless power techniques mainly fall into two categories, near field and far-field. In near field or non-radiative techniques, power is transferred over short distances by magnetic fields using inductive coupling between coils of wire, or by electric fields using capacitive coupling between metal electrodes.[3][4][5][6] Inductive coupling is the most widely used wireless technology; its applications include charging handheld devices like phones and electric toothbrushes, RFID tags, induction cooking, and wirelessly charging or continuous wireless power transfer in implantable medical devices like artificial cardiac pacemakers, or electric vehicles.
[Nikola Tesla: Early Energy Harvesting](https://medium.com/supplyframe-hardware/nikola-tesla-early-energy-harvesting-6f40a73733cb)
## transformative?
[Experimental device generates electricity from the coldness of the universe](https://phys.org/news/2019-05-experimental-device-electricity-coldness-universe.html)
> ... the current device can theoretically generate almost 4 watts per square meter, roughly one million times what the group's device generated and enough to help power machinery that is required to run at night.
> By comparison, today's solar panels generate 100 to 200 watts per square meter.