Salman Waghu (talk | contribs) No edit summary |
|||
| Line 48: | Line 48: | ||
* | * | ||
* | * | ||
===A NEW GENERALIZED DETAILED BALANCE FORMULATION TO CALCULATE SOLAR CELL EFFICIENCY LIMITS=== | |||
[http://ucep.gatech.edu/papers/honsberg-generalDB.pdf , 2001, Honsberg, CB, Corkish, R, Bremner, SP,17th European Photovoltaic Solar Energy Conference, 22-26,Honsberg2001 ] | |||
*Two ways to calculate solar efficiency - thermodynamics & detailed balance equation | |||
*both give same results | |||
*new detailed balance equation taking into consideration non ideal and non radiative processes | |||
*inclusion leads to higher efiiciencies | |||
Revision as of 19:14, 6 February 2016
Note
This is a literature review page for investigating on Intellectual Property (IP) barriers to Photovoltaic solar cells efficiency. It would be our pleasure if you share your experience in this area with us. (Discussion tab is top left of this page)
Background
Meaning of Intellectual Property: Term of Intellectual Property (IP) refer to the rights that is given by the law to the person who create, innovate or designed a new thing. There are various types of IP such as trade market, copyright, patents, industrial design rights, all artistic works and much more. This phrase (IP) was used for the first time in 1769 but its most ever use refer to the end of 20th century till now. By this law inventors feel more secure to publish their work to the public because all benefits of that invention must refer to the inventor.Intellectual Property Wikipedia
Literature Review
The IP landscape for photovoltaics
- pv patent in us 1968-2008
- patent applications
- Principal categories in PV patents (Materials, Control, Manufacturing,..)
Business, market and intellectual property analysis of polymer solar cells
- companies and markets, it seems easy to copy, risk for commercial motivation, Konarka is first in market, Probably has biggest patent portfolio
- valuable patent search engines [82-84]
- eminent universities and factories who own the most number of patent are introduced in section 4.8
- 170 countries are member of Paris Convection and 140 of them have signed the Patent Cooperation Treaty (CPT)
- Difference between Patent Application & Patent
- First a patent is published in international mode then goes on national and then regional
Photovoltaic cell basic information
Photovoltaic Cell Conversion Efficiency Basics
these parameters have effect on PV cells efficiency
- Wavelength of light: solar cell cannot absorb entire spectrum of sunlight. Photons with energy below the material bandgap cannot be absorbed and photons with higher energy, will loose their extra energy as heat or light.
- Recombination: produced electrons and holes will recombine before contribute in cell's current.This can be due direct recombination, which electrons and hols meet each other randomly, or indirect recombination which is due to impurities, structure defects or surface recombination.
- Natural resistance: this happen in bulk material, thin surface and contact point of panel to output circuit
- Temperature: Almost all solar cells lose their efficiency by growing temperature. Considering the most part of incident sunlight convert to heat in solar cell, then operating temperature would be an issue for solar cells. operating T can be considered when designing the solar cells to be a good match or somehow manage to cool the panel for higher efficiency.
- Reflection: A big portion of sunlight would be reflected on the solar cell surface (30%) if find a way to reduce the reflection, it means there would be more photon available to generate more electron-hole pairs and efficiency of light increases in result. Many methods are introduced to reduce the reflection such as anti reflection coating (multi layers) and texture the top surface of solar cell.
- Electrical Resistance: It is obvious that by larger electrical contact, electrical resistance would reduce but on the other hand more incident light will be blocked. It means there is a trade off between size of metal contact on the surface and electrical resistance for solar cells. Nearly, new methods are being introduced to overcome this issue like using a very thin transparent metal contact all over the solar cell surface.
Photovoltaic technology development: A perspective from patent growth analysis
- In this paper is tried to find a direct relation between the crude oil price and the number of registered patents. In the graph he draw number of patent graph one year ahead (When the price of crude oil increase, more money will inject to the R&D in PV which will take time for a patent come out, in average one year)
- In this paper very nicely a search strategy for relevant patent in PV is described in section 4
- five different category for PV solar cells was achieved (1)Emerging PV include:polymer and dye-sensetive (2)Silicon include: bulk type and thin film silicon (3) CdTe (4)CIGS (5)Group III-V materials.
- by the number of patent in these groups it is obvious that most focus of research are in category 1,2&5 and can see that scientist are not so much interested in categories 3&4
- mentioned in this paper that there is a 10 years lag between PV market and its technology development.
Intellectual property rights and low carbon technology transfer: Conflicting discourses of diffusion and development
- Two sides of IP debates, one group believe this is kind of public good and must be supported by international funds and be accessible for developing countries like as drugs for treating HIV, in contrast, the other side they argue if developing countries be more serious in protecting IPR, the transfer technology would be much easier
A NEW GENERALIZED DETAILED BALANCE FORMULATION TO CALCULATE SOLAR CELL EFFICIENCY LIMITS
- Two ways to calculate solar efficiency - thermodynamics & detailed balance equation
- both give same results
- new detailed balance equation taking into consideration non ideal and non radiative processes
- inclusion leads to higher efiiciencies