Micro Power Generation

A. Wood, S. Eickhoff Active micro power generator AMPGen , DARPA-MTO webpage, 2004, http //www. darpa.mil/mto/mpg/summaries/2004 summaries/honeywell.html... 

Micro coolers Micro energy harvesting Micro energy scavenging Micro fuel cells Micro heat engines Micro power generation Microengines Micropropulsion Power MEMS... 

Chou, S.K., Yang, W.M., Chua, K.J. etal. (2011) Development of micro power generators GQ6 A review. Applied Energy, 88, 1-16. 

Foam heat exchanger Foam produced from a metal-coated polymer foam Aerospace, micro-power generation, compact and micro-reactors 3,4... 

Sakane Y, Suzuki Y, Kasagi N (2008) The development of a high-performance perfluorinated polymer electret and its application to micro power generation. J Micromech Microeng 18 104011... 

Naruse Y et al (2009) Electrostatic micro power generator fiom low frequency vibration such as human motion. J Micromech Microeng 19(9) 094002 Neugschwandtner GS et al (2000) Large and broadband piezoelectricity in smart polymer-foam space-charge electrets. Appl Phys Lett 77(23) 3827-3829 Paajanen M et al (1998) Electro-mechanical film EMFi-a new multipurpose electret material. Sensors Actuators A 84(l-2) 95-102... 

Sakane Y et al (2008) Development of high-performance perfluoriented polymer electret film and its application to micro power generation. J Micromech Microeng 18(10) 104011 Sato R, Takamatsu T (1986) An electret switch. IEEE Trans Electr Insul 32(3) 449 55 Schaffert RM (1975) Electrophotography. Wiley, New York Sessler GM, West JE (1962) US Patent 3,118,022... 

Chen, S.N., Wang, G.J., Chien, M.C., 2006. Analytical modeUing of piezoelectric vibration-induced micro power generator. Mechatronics 16, 387—397. 

Barton, P.I., Mitsos, A. and Chachuat, B. (2005) Optimal start-up of micro power generation processes. Presented at the ESCAPE 15, Barcelona, Spain, 29 May-1 June 2005. 

Capstone Micro Turbine Sales Literature, Simple Cycle Micro Turbine Power Generation System, 2000, Chatsworth. California. 

Dahm, W. J. A., Ni, J., Mijit, K., Mayor, R., Qiao, G., Benjamin, A., Gu, Y., Lei, Y., and Papke, M., Micro internal combustion swing engine (MICSE) for portable power generation systems. In the 40th AIAA Aerospace Sciences Meeting and Exhibit, Reno, 2002. 

Technical progress as well as investments in PEMFCs for transportation, stationary, portable, and micro fuel cell applications has been dramatic in recent years. The present view is ophmistic for fuel cell power generation the status is presently at the field trial level, or early commercialization stage, moving into volume commercialization. Although commercially viable, niche PEMFC applicahons exist today, the first commercial mass markets for fuel cells are expected to be for handheld electronic devices, PCs, and other portable devices. 

Thus far, tubular design cells are the most reliable cells against thermal stresses and chemical degradation of the performance. Siemens Power Generation has demonstrated the performance and reliability of SOFC systems with tubular cells [6], The 100 kW CHP system has been operated for more than 20000 h, and it was reported that no degradation of the system was observed. To prove the feasibility of a GT/SOFC hybrid system, a 220-kW hybrid system with an SOFC generator integrated with a micro gas turbine has been demonstrated at the University of California this system has shown a conversion efficiency of around 49% (HHV). 

This chapter deals with development work in the field of micro structured fuel processors, which convert various fuels to hydrogen for fuel cells and other power generation modules. 

Hessel, V., Microstructured Reformer for fuel-cell applications, in Proceedings of the 3rd International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion, PowerMEMS (4—5 Dec. 2003), Global Emerging Technology Institute, New York, Makuhari, Japan, 2003. 

A new concept DMFC based on well considered electrochemical background and MEMS process was designed and fabricated [3]. The structure is shown in Fig. 5.1. The main feature of this device is the planer structure and the integration of anodes and cathodes side by side. This device has two micro channels for introducing new fuel solution and oxidant solution to the reaction area continuously to achieve high power generation. Another feature is that the inclement of the electrode surface area compared to the planer electrode used in the conventional bipolar type pDMFC. 

The fuel solution is fed into the anode side channel. Methanol reacts at the anode and releases electrons, protons, and carbon dioxide. At the cathode, molecnlar oxygen reacts with proton being transported throngh the PEM (Polymer Electrolyte Membrane) from the anode and prodnces water. The electrons travel throngh the external circnit to the cathode. Power generation is performed by the above oxidation-rednction reaction principles. In order to realize micro-mini power sonrces, large nnmbers of DMFC shonld be integrated serially on a substrate. The structure of the proposed DMFC is suitable for this application. 

A thermionic converter with a plane parallel type of a polycrystalline W emitter and an AgO X collector, an interelectrode spacing at room temperature 0.1mm, was set up and the power generation experiments were conducted. The maximum power, 3.9W/cm, 0.6V, 6.5A/cm, was obtained under the unignited mode operation at T e =1583K. The barrier index was V b =1.5V at T e =1578K. Based on the experimental results, a new type of a FGM collector was proposed for a micro-gap thermionic converter. 

Moreover, there is a current need of miniaturized propulsion system for widening the capabilities of low cost micro-satellites. Recently, the development of a turbo-pump fed miniature rocket engine has been proposed as a new propulsion system for micro-satellites (10 to 100 kg) [6] the bipropellant tlmister uses 70 wt.-% H2O2 as oxidizer and ethanol as fuel. The engine displays four sub-components (i) two propellant micro-pumps, (ii) a HP decomposition chamber, (iii) a turbine coupled to an electric power generator and driven by the hot gas released from HP decomposition, and (iv) a thruster for the combustion reaction. 

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