As a guide for the acquiring more insight into the SunCell emission from the videos, consider that the emitted radiation drops off as one divided the radius squared. The radius of the SunCell PV window cavity is 3 inches; so at 10 feet or 120 inches away, the radiation is 1600 times less. Say a target power is 100,000 W of light emission from the surface of the window cavity of area 0.1 m2. Then, the required optical power density at the window surface is 1 MW/m2 or about 1000 Suns which is an operating intensity of concentrator photovoltaics. Using the blackbody calculator provided at this link:
https://spectralcalc.com/blackbody_calculator/blackbody.php
and using a high-pressure plasma emissivity of 1, the required blackbody temperature is 2073 K (1800 °C) corresponding to a Radiant emittance: 1.04718e+06 W/m2. This blackbody temperature corresponds to a color temperature of about reddish-yellow:
The SunCell typically emits white to blue light. But considering the one megawatt per square meter emitted at the window surface and recorded at the distance of 10 feet (120 inches) away, the radiation intensity is 625 W/m2 which is less than that of Sunlight (1000 W/m2). Given the PV window volume of 2.78 liters the corresponding power density is 36 W/cm3, and the majority of the power occupies a third or less of this volume corresponding to over 100 W/cm3 for this example. The SunCell power density compares well with that of lithium-ion batteries of 0.7W/cm3, and also the internal combustion engine wherein the most power dense internal combustion engines ever made are about 240 W/ cm3 [https://carbuzz.com/most-power-dense-engines/].
The “July 18 Station 2” Youtube video shows 221A, 34.84V on one of the machine readouts. Does this mean that station 2 was getting 7.7kw of input power during operation? Assuming 1MW/m2 this represents a very high COP. This may not even represent the “low input” tests that Brilliant is currently investigating.
It’s tempting to guess at COP from available data. Certainly, it is a foremost concern, along with run duration and output power. Input power is a simple matter if measured at line (or mains, if you’re British). If measured at input of the reactor, it has a highly variable voltage, current and phase, all of which determine the instantaneous power.
Thank you, this clears up a question or two I’ve had around the recent July videos of Suncells in operation.
This is helpful, but… what does “Given the PV window volume of 2.78 liters the corresponding power density is 36 W/cm3,…” mean? That refers to the quart vessel?
Dr. Mills, can you say what the actual measured radiation intensity of the light is for these runs? Thanks.