Dual energy use systems: district heating survey. Final report

Proper adjustment of domestic hot water (DHW) load structure can balance energy demand with the supply. Inefficiency in primary energy use prompted Omsk DH company to be a strong proponent of a flow controller at each substation. Here the return temperature is fixed to the lowest possible value and the supply temperature is solved. Thirty-five design scenarios are defined for each load deviation index with equally distributed outdoor temperature ranging from +8 for the start of a heating season towards extreme load at temperature of -26°C. All the calculation results are listed. If a flow controller is installed, the customers might find it suitable to switch to this type of DHW supply. Considering an option with direct hot water extraction as usual and a flow controller installed, the result indicates that the annual heat consumption will be lower once network temperatures during the fall or spring months are higher. The heat load profiles obtained here may be used as input for a simulation of a DH substation, including a heat pump and a tank for thermal energy storage. This design approach offers a quantitative way of sizing temperature levels in each DH system according to the listed methodology and the designer's preference.

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Analysis of energy signatures and planning of heating and domestic hot water energy use in buildings in Norway

E3S Web of Conferences ◽

10.1051/e3sconf/201911106009 ◽

2019 ◽

Vol 111 ◽

pp. 06009

Author(s):

Tymofii Tereshchenko, ◽

Dmytro Ivanko ◽

Natasa Nord ◽

Igor Sartori

Keyword(s):

Energy Use ◽

District Heating ◽

Energy System ◽

Energy Performance ◽

Multiple Regression Model ◽

Hot Water ◽

Temperature Dependent ◽

Domestic Hot Water ◽

Dependent Part ◽

Energy Signature

Widespread introduction of low energy buildings (LEBs), passive houses, and zero emission buildings (ZEBs) are national target in Norway. In order to achieve better energy performance in these types of buildings and successfully integrate them in energy system, reliable planning and prediction techniques for heat energy use are required. However, the issue of energy planning in LEBs currently remains challenging for district heating companies. This article proposed an improved methodology for planning and analysis of domestic hot water and heating energy use in LEBs based on energy signature method. The methodology was tested on a passive school in Oslo, Norway. In order to divide energy signature curve on temperature dependent and independent parts, it was proposed to use piecewise regression. Each of these parts were analyzed separately. The problem of dealing with outliers and selection of the factors that had impact of energy was considered. For temperature dependent part, the different methods of modelling were compared by statistical criteria. The investigation showed that linear multiple regression model resulted in better accuracy in the prediction than SVM, PLS, and LASSO models. In order to explain temperature independent part of energy signature the hourly profiles of energy use were developed.

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Environmental Comparison of Energy Solutions for Heating and Cooling

Sustainability ◽

10.3390/su11247051 ◽

2019 ◽

Vol 11 (24) ◽

pp. 7051 ◽

Cited By ~ 3

Author(s):

Ida Franzén ◽

Linnéa Nedar ◽

Maria Andersson

Keyword(s):

Environmental Impact ◽

Geothermal Energy ◽

Energy Use ◽

District Heating ◽

Conventional System ◽

Three Solutions ◽

Air Conditioners ◽

Heating And Cooling ◽

Energy Flows ◽

One Year

Humanity faces several environmental challenges today. The planet has limited resources, and it is necessary to use these resources effectively. This paper examines the environmental impact of three energy solutions for the heating and cooling of buildings. The solutions are conventional district heating and cooling, a smart energy solution for heating and cooling (ectogrid™), and geothermal energy. The ectogrid™ balances energy flows with higher and lower temperatures to reduce the need for supplied energy. The three solutions have been studied for Medicon Village, which is a district in the city of Lund in Sweden. The study shows that the energy use for the conventional system is 12,250 MWh for one year, and emissions are 590 tons of CO2 equivalents. With ectogrid™, the energy use is reduced by 61%, and the emissions are reduced by 12%, compared to the conventional system. With geothermal energy, the energy use is reduced by 70%, and the emissions by 20%. An analysis is also made in a European context, with heating based on natural gas and cooling based on air conditioners. The study shows that the environmental impact would decrease considerably by replacing the carbon dioxide intensive solution with ectogrid™ or geothermal energy.

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