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- Delsing, Jerker, et al.
(författare)
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Projekt: Fjärrvärme
- 2007
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Annan publikation (populärvet., debatt m.m.)
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| 5. |
- Jomni, Yassin, et al.
(författare)
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Architecture for internet enabled measurements in a district heating substation laboratory
- 2005
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Ingår i: Proceeding AMCTM 2005.
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Konferensbidrag (refereegranskat)abstract
- An architecture for the energy measurement and control and monitoring at a district heating substation is propsoed. A district heating substation is comprised of a set of sensors and actuators crutial for the well being of the substation. We want to make the data from the sensors available over the internet and provide access to the control system of the district heating substation over the internet. This technology will be implemented in a district heating laboratory being constructed at Lulea ̊ University of Technology.The architecture is based on wireless sensor and actuator nodes each talking the TCP/IP Internet suite of protocols. The implementation is made with the wireless Embedded Internet System plattform MULLE that supports the TCP/IP suite of protocols. The basic architecture and means for its implementation is given. Other applications where this vision can be readily applied are for example, sports and metrology.
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| 6. |
- Jomni, Yassin, et al.
(författare)
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Improving heat energy measurement using a feed-forward method for low power applications
- 2004
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Konferensbidrag (refereegranskat)abstract
- Heat measurement errors cause large revenue discrepancies in the district heating industry. Some of these errors are static and can be estimated using standard error analysis, but the largest error cause is the dynamic load such systems are subject to, as in the case of warm water tapping. The frequency at which heat meters estimate and update the energy is either constant or depends on the flow rate. They are often battery operated and their power consumption is proportional to their estimation frequency. Heat meters with a flow rate dependent estimation frequency are usually based on volume-flow meters. They are widely used in district heating due to their lower estimation frequency, which prolongs their battery life. Such devices are inaccurate especially at low flow rates. A Feed-forward method that measures the heat energy only when changes occur is presented in this paper.This method reduces the heat measurement error due to the dynamics of the system while minimizing the battery power consumption. The Feed-Forward method has been implemented and tested at cross-purposes with flow rate dependent heat meters in a Simulink model of a district heating substation.
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- Ståhlbröst, Anna, et al.
(författare)
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Energy savings by user interaction and visualisation
- 2012
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Ingår i: The 35th Information Systems Research Seminar in Scandinavia – IRIS 2012.
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Konferensbidrag (refereegranskat)abstract
- Environmental issues are a reoccurring discussion topic among politicians, researchers and citizens all around the world. Climate changes and pollution are both important issues that need to be dealt with to slow down their impact. Within the IS area, the acknowledgement of these issues has been slow, and it is now time to start contributing. In this paper an illustration of an approach to user interaction for energy saving is given. We present a research project in which a visual energy information system has been co-created and installed in an elementary school. The effects of the system on the pupils and staff energy consumption behaviour are evident. The school have save approximately 20% on lightning in their classrooms. Based on the pupil’s feedback during the project, we present five factors that are important to consider when designing energy visualisations.
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- Yliniemi, Kimmo, et al.
(författare)
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Experimental verification of a method for estimating energy for domestic hot water production in a 2-stage district heating substation
- 2009
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Ingår i: Energy and Buildings. - : Elsevier BV. - 0378-7788 .- 1872-6178. ; 41:2, s. 169-174
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Tidskriftsartikel (refereegranskat)abstract
- In this paper we compare our estimate of energy consumption for domestic hot water production in a building with the measured value. The energy consumption for hot water production is estimated from the measured total power consumption. The estimation method was developed using computer simulations, and it is based on the assumption that hot water production causes rapid and detectable changes in power consumption. A comparison of our estimates with measurements indicates that the uncertainty in estimation of hot water energy consumption is ±10%. Thus, the estimate is comparable to class 3 energy meter measurements, which have an uncertainty of ±2-10%.
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| 15. |
- Yliniemi, Kimmo
(författare)
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Fault detection in district heating substations
- 2005
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis gives a summary of different faults that occur in district heating substations and suggests ways of detecting them. The aim of the research has been to achieve fault detection using only the heat meter and the sensors connected to it, namely two temperature sensors and one flow meter. The incentive for fault detecting district heating substations comes from an effort to keep them in proper working order so as to be able to keep a low return temperature in the network and thus be able to lower the supply temperature. Hypothetically, if the supply temperature in Sweden were lowered by only one degree, the annual savings would be about SEK 50 million. The thesis also entails brief accounts of district heating and heat metering along with two models of heat exchangers. The first paper in this thesis presents a way of fault detecting the temperature sensors by detecting the noise amplitude. The second paper describes how to separate the energy usage for heating and domestic hot water production using only one heat meter. Energy separation is very interesting, since separate measurement of domestic hot water energy usage and heating usage is recommended by the Swedish National Board of Housing, Building and Planning. The third paper describes how to estimate hot water consumption using the hot water energy consumption and measurement of cold water and hot water temperature. It also contains an error analysis of the estimate. The error analysis suggests that the estimate using a class 1 heat meter is as accurate as the measurement using a class-3 flow meter. Thus, the two estimation methods presented can be used instead of installing extra heat meters or flow meters. This makes it possible to implement the separate measurement(s) according to the recommended guidelines at a lower cost.
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| 19. |
- Yliniemi, Kimmo, et al.
(författare)
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Sensor fault detection in a district heating substation
- 2005
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Ingår i: Proceedings of the 10th IMEKO TC10 International Conference on Technical Diagnostics.
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Konferensbidrag (refereegranskat)abstract
- This paper describes a method of detecting temperature sensor faults in a district-heating substation (DHS). It uses valve position monitoring and variance monitoring to detect sensor faults. Depending on user requirements the method can be customized either to detect faults quickly or to have a low false alarm rate and be able to detect smaller noise increases but at the expense of longer detection time. The result is a method that uses a limited amount of computing power and does not require much computing precision, since the only computing done is addition of integers. The method is therefore suitable for implementation in a microcontroller.
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