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Micro-cogeneration is cogeneration with small performance, with maximal electric power up to 50 kWe. On the present, there are available small micro-cogeneration units with small electric performance, about 1 kWe, which are usable also in single family houses or flats. These micro-cogeneration units operate on principle of conventional combustion engine, Stirling engine, steam engine or fuel cell. Micro-cogeneration units with fuel cells are new progressive developing type of units for single family houses. Fuel cell is electrochemical device which by oxidation-reduction reaction turn directly chemical energy of fuel to electric power, secondary products are pure water and thermal energy. The aim of paper is measuring and evaluation of operation parameters of micro-cogeneration unit with fuel cell which uses natural gas as a fuel. [ABSTRACT FROM AUTHOR]

This paper describes a dynamic price mechanism to coordinate eletric power generation from micro Combined Heat and Power (micro-CHP) systems in a network of households. It is assumed that the households are prosumers, i.e. both producers and consumers of electricity. The control is done on household level in a completely distributed manner. Avoiding a centralized controller both eases computation complexity and preserves communication structure in the network. Local information is used to decide to turn on or off the micro-CHP, but through price signals between the prosumers the network as a whole operates in a cooperative way. [ABSTRACT FROM AUTHOR]

Droplet manipulation is one of the important applications of the SAW device. When a droplet is placed on a SAW device, the longitudinal wave radiates into the droplet. Nonlinear acoustic phenomena are caused by the radiated longitudinal wave from the SAW. Droplet manipulation is one of those phenomena. It is important to investigate the minimum radiation force to manipulate the droplet by the SAW. In this paper, the radiation force in a droplet is experimentally measured. The radiation force was measured by varying an applied electrical power, water volume, and concentration of glycerol-water mixture. The minimum radiation force for manipulating 10 micro little was 0.168 mN. Also, the water droplet manipulated was observed by a high speed camera. When the longitudinal wave radiates into the droplet and the radiation force is larger than the surface tension of the water, the tip of the droplet is extended in the SAW propagation direction. In other words, the radiation force is acting only tip of the droplet. The extended length depends on the applied power and the duty factor. Other parts of the droplet act as binding force. The force only acts the tip of the droplet and the end part is dragged. [ABSTRACT FROM AUTHOR]

A brief overview of why it is important to think of energy in a sustainable way is given. The starting point is that the future of mankind depends on a sufficient energy supply, both in terms of electric power and liquid fuels, at present based on fossile resources. A shift of paradigm towards Sustainable Development is needed, based on ethical considerations and on some legal rules. A possible technological solution to the liquid fuel problem is also presented. [ABSTRACT FROM AUTHOR]