As a branch off from another thread in this forum I would like to use this thread to discuss the technology behind the V3Solar project. I came across this project some months ago but until now I have not posted anything about it. Their website is:
http://v3solar.com/
Firstly here a video of the tech (please take the time to read the rest of this post before commenting):
In order to understand the operating principles behind the system I have copied the below directly from their website here: http://v3solar.com/technology/readfirst/
Quote:
"V3Solar takes a known fact: Concentration of light increases the production of electrical energy in PV.
And solves a known problem: Concentration of light increases heat, which decreases the production of electrical energy in PV.
Current solar power theory estimates that a square meter of sunlight has a maximum energy content of 1,000 watts. Based on this, a 20% efficient photovoltaic (PV) panel should produce 200 watts of energy from one square meter of sunlight.
Through its unique patent pending design, V3Solar’s Spin Cell is able to concentrate 20X more sunlight on 1X sun mono PV without the cells overheating. This is achieved through a combination of solar concentrating lenses and unique thermal management. The outer cone is larger and focuses the light on the smaller, inner cone that is populated with PV.
Light is transferred to electricity in nanoseconds. Heat is transferred in milliseconds (1,000,000X longer). The PV on the inner cone of the Spin Cell captures the light, generates the electrical energy, and then spins away before the heat can be transferred to the PV.
The V3solar patent pending design also delivers a higher level of efficiency from PV. Tests to date have shown improvements under laboratory conditions of around 20%, which effectively lifts the efficiency of the PV from 20% to 24%.
The Spin Cell’s ability to concentrate light dramatically reduces the amount of PV required for a given output, thus reducing the cost per watt. The improved efficiency of the PV means that less light is required to create the same amount of watts, further reducing costs and improving efficiency of the overall unit. With a 20X concentration of the sunlight, the Spin Cell can produce the same amount of power while using 5% of the PV material. Since the lensing costs 92% less than the PV material, this lowers the cost/watt.
To put it all in one sentence, the Spin Cell concentrates more light on the PV cells, while maintaining a low operating temperature, and the patented spin further improves the efficiency of the PV to increase the total amount of energy produced by each Spin Cell, while lowering the cost per watt."
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Note that the device uses 20x magnification optics on a reduced area of PV, and not what some critics claim as 20x the power output of flat panel PV! They clearly say there is an efficiency gain to 24% of the solar to electricity conversion rate, NOT 20% x 20 = 400% efficiency! Together with the magnification elements of the system they will use 20x less PV material or only 5% of the PV material required for the same output flat PV module.
They also claim a few things about the "latency" of heating versus "lighting" effect that is meant to help keep it cool as the PV cells rotate inside the hermetically sealed concentrating lense cover. The principle is similar as used for X-ray imaging with a rotating anode as described here: http://labspace.open.ac.uk/mod/resource/view.php?id=361885
Apparently this allows the system to benefit from the 20x magnification without the associated temperature derate and heat failure associated with conventional PV concentrating systems.
The rotating assembly is without "moving parts" per se and is suspended by magnets (maglev style), which are also the same magnets that are used as the rotor for the "inverter less" AC alternator, that converts the DC current from the PV to Grid type AC. The device can also be configured to deliver DC out as well (a simple rectifier would suffice). Effectively the rotational torque produced by the DC PV produces the force that drives the AC alternator. From what I can tell from the limited information I have found so far is that I assume it runs similar to a coupled motor-alternator to create AC from DC.
(If this is so, a previous idea I had would add another "spin" My idea would be to use the torque to drive a intermediary flywheel system between the rotating top and base, for energy storage internally, instead of using batteries. Hopefully this would lead to greater base load and load following capacity (similar to a conventional fuel powered alternator) and significantly increase network stability with solar PV, especially for short term network loads and transients. There are a couple of flywheel systems installed in WA already, however an integrated version like this does not exist yet to my knowledge. Another benefit would be that the grid frequency synchronisation would be independent of the rpm required to keep the PV rotating at optimum for sunlight collection (incorporating the proposed V3 effects), and the built in variability via a power factor type field control of a AC alternator could be used to optimise PV output, similar to a MPPT controller. In effect it would be an electro- mechanical PV to AC inverter with flywheel energy storage.)
The cone shape also has some interesting properties for placement on the ground and even for mounting multiple modules on a pole. The cone shape seems to prevent shading typically assosiated with tracking PV systems and allows for a higher density placement of the modules, which results in further savings in installation costs.
There are two things that I think still that needs further consideration from the v3solar claims:
One is the "bucket" effect apparently due to the current - voltage characteristic of semiconductors. The effect exists from what I can tell, but to what extent I am still uncertain. Maybe it's just a bad metaphor of something that works technically?
The other is a phenomenon that is claimed to increase performance that I have not yet been able find much information on. That is the one where apparently the "flashing" at sunset or "penumbra effect" increases the intensity and energy harvested by the system. The sunset effect is real from what I can tell (http://en.wikipedia.org/wiki/Green_flash), but information on how it effects PV output is not easy to come by. Of course this optical flashing could also help system efficiencies, if it is of enough magnitude and frequency.
On that basis I would welcome any posts that have some technical background included, rather than just of the cuff "won't work" remarks. I'd like to hear why people think it doesn't work, or just what components won't, as to evaluate it's technical merit. Thanks in advance for your inputs.
Regards
JB
