Sensible Solutions (Sweden)

As a part of the transition of the energy system towards renewables, new technologies and combinations of technologies are emerging. These include utilization of medium temperature industrial processes or availability of surplus heat from renewables. For these applications, organic Rankine cycles may be cost efficient solutions, if both expander work and condenser heat may be utilized as valuable products. In this study, a solar powered organic Rankine cycle using a zeotropic mixture is investigated from a design perspective. Both an Exergy and Exergoeconomic analysis were conducted. The investigated unit is capable of co-producing approximately 30 kW electricity and 160 kW district heating with a exergetic efficiency of > 60 %. The unit is able to compete with existing renewable power generating systems in terms of specific cost of electricity.

Detection of forest wildfires at early stages can significantly improve the success of fire fighting and thus it contributes to the damage and cost reduction. Surface deployed sensor networks linke ...

This work discuss the possibilities of integrating passive sensor components to passive UHF RFID tags. The sensor system works by degrading a tag's communication performance in proportion to a sensed quantity. Two approaches are studied, sensors directly integrated to tag antenna structures and sensors electromagnetically coupled to tag antennas. The em coupled sensors provide the possibility to produce small sensor components as easily applied add-ons to ordinary commercial RFID tags.

Placing fire detectors in a forest is usually associated with powering problems since the sensors do not have access to external power supply and a periodical change of internal batteries is an undesired option. This paper presents an approach where the fire sensor itself, when heated by nearby fire, generates electrical energy to power a radio transmitter. Presented energizing fire sensor is environmentally friendly and can be mass produced at a very low cost. Upon activation the sensor produces enough power necessary to operate most standard radio transmitters depending on what communication system is chosen for operation. The fire detector unit can be deployed from either helicopter or manually from the ground. The sensor can be designed to activate itself at different temperatures to suit different climate zones. Rough guidelines are given for estimation of attenuation of radio wave propagation in forest areas in order to predict maximum transmit distance.