| 1. |
- Mirzanamadi, Raheb, 1987, et al.
(author)
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Anti-icing of road surfaces using Hydronic Heating Pavement with low temperature
- 2018
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In: Cold Regions Science and Technology. - : Elsevier BV. - 0165-232X. ; 145, s. 106-118
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Journal article (peer-reviewed)abstract
- A traditional method to mitigate slippery conditions on a road surface is to spread out sand and salt. This method results in corrosion of the road infrastructures and damage to surrounding vegetation. A renewable alternative method for anti-icing the road surface is to use a Hydronic Heating Pavement (HHP). The HHP consists of embedded pipes in the road. A fluid as thermal energy carrier circulates through the pipe. The energy is harvested in summer and saved in seasonal thermal energy storages. The harvested energy, as the only source of energy, is released in winter for snow/ice melting. The aim of this study is to investigate the anti-icing performance of the HHP system during cold periods. A two-dimensional numerical model was developed to investigate how different design options, such as distance between the pipes, affect the efficiency of the HHP systems. The annual required energy for anti-icing and remaining hours of the slippery conditions on the road surface were numerically calculated using a finite element model. The numerical model was validated for two cases: (i) for a road without pipes using a one year measured data of an existing road and (ii) for a road with embedded pipes using an analytical solution. The validation results for a road without pipes showed that the mean annual temperature difference of the road surface is 0.28 °C with standard deviation of 3.53 °C between the measured data and numerical calculation. The validation results for the road with embedded pipes showed that the maximum relative error associated with the thermal resistance between the pipes and surface is less than 1% between the numerical model and the analytical solution. In order to investigate the anti-icing performance of the HHP system, the climate data from Östersund, an area in middle of Sweden, were selected. The results revealed that the anti-icing performance of the HHP system improves when the pipes are placed closer, the depth of embedded pipes is reduced, large pipe sizes are used and when the road surface has a lower emissivity value. Among all options, the distance between pipes has the most significant effect on improving the anti-icing performance, so changing the pipe distances from 400 mm to 50 mm results in approximately four times shorter hours of the slippery conditions on the road surface.
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| 2. |
- Adl-Zarrabi, Bijan, 1959, et al.
(author)
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Hydronic Pavement Heating for Sustainable Ice-free Roads
- 2016
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In: Transportation Research Procedia. - : Elsevier BV. - 2352-1465 .- 2352-1457. ; 14, s. 704-713
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Conference paper (peer-reviewed)abstract
- Hydronic pavement is an alternative method for de-icing of roads. A hydronic pavement (HP) could be more environmental friendly than traditional de-icing methods such as salting. The HP system consists of embedded pipes in the pavement structure, with a fluid as energy carrier. The performance of a HP system strongly depends on a number of parameters e.g. the location of the pipes, the thermal properties of pavement structure and the temperature level of the heat storage system. In this paper initial results related to the designing of a HP system are presented.
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| 3. |
- Adl-Zarrabi, Bijan, 1959, et al.
(author)
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Hydronic Pavement Using Low Temperature Borehole Thermal Energy Storage
- 2016
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In: Advances in Civil, Environmental and materials research (ACEM16). - 9788989693444 ; , s. 14-
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Conference paper (peer-reviewed)abstract
- Winter conditions on roads are a challenge for road administrators in cold climates and with increased public demands on safety, winter maintenance activities will increase. The most common winter maintenance activity in Scandinavia is anti-icing, which is performed when it is a risk for ice formation on the road surface. Commonly a truck is utilized for spreading freeze point depressant, like salt, on the pavement thereby lowering the freezing point and preventing ice formation on the surface. This method has been questioned for a number of reasons e.g. salts have negative effects on the local environment. An alternative method for de-icing is to use hydronic pavement (HP). HP consists of a pipe network, embedded inside the pavement, in which a fluid is circulated. The fluid collect solar energy during summer days and transports heat back to the road surface during icy winter days. The harnessed and released energy should be in balance, otherwise an additional heat sources is needed. This study has investigated the possibility of developing an alternative strategy to heat the pavement surface with stored low temperature fluids. By using the methodology, and software BRIDGESIM, a preliminary design of a hydronic pavement system have revealed that it is not feasible to design a system for the cold climate of Ö stersund (Sweden); only relying on harnessing solar energy and store the energy in a borehole thermal energy storage. However it was revealed that it is possible to design HP system for low supply temperatures of about 7 °C. Which is far below the supply temperature of about 35 °C, recommended by manufacturers of HP system. The prospect of utilizing low-temperature heat sources would make HP system more energy efficient which could make it an alternative to traditional winter maintenance methods.
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| 4. |
- Adl-Zarrabi, Bijan, 1959, et al.
(author)
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Safe and Sustainable Coastal Highway Route E39
- 2016
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In: Transportation Research Procedia. - : Elsevier BV. - 2352-1465 .- 2352-1457. ; 14, s. 3350-3359
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Conference paper (peer-reviewed)abstract
- The project “Coastal Highway Route E39” have a mandate to, investigate how infrastructure can exploit renewable energy to reduce environmental footprint. Three PhD projects were initiated on this subject at Chalmers University of Technology by Norwegian public road administration. Results in this paper conclude that (1) Life Cycle Assessment should have a geographical dimension with respect to assumptions and input data, (2) there are substantial potential to reduce the CO2 emissions from the E39, especially when considering an electrification, and (3) the harvested energy from hydronic pavement system can be enough for maintaining ice-free roads in Nordic countries.
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| 5. |
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| 6. |
- Johnsson, Josef, 1986, et al.
(author)
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A numerical and experimental study of a pavement solar collector for the northern hemisphere
- 2020
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In: Applied Energy. - : Elsevier BV. - 1872-9118 .- 0306-2619. ; 260
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Journal article (peer-reviewed)abstract
- Solar energy is a renewable energy source that is globally available. To utilise this type of energy, novel tech- nologies are developed across the globe. Among these, the pavement solar collector (PSC) technology has a considerable potential. A PSC consist of pipes, that are embedded into the upper pavement layers through which fluid is circulated. Solar radiation heats the pavement surface, and the absorbed heat is transferred to the cir- culating fluid. One applications is to use the heat for recharging shallow geothermal boreholes with solar energy during summer, thereby reducing the electricity consumption of ground source heat pumps during winter. In Scandinavia, however, the knowledge on the PSC application is limited. The Swedish transport administration has therefore established a field station to gain more insight on the PSC in Scandinavia. This paper reports the findings of the investigation from the summer of 2018 and how the efficiency of the PSC is affected by altering the albedo, fluid flow rate, and pipe spacing. The measured harvested energy is 245 kWh/m2 with a solar efficiency of 42%. It is found that by altering the albedo and flow rate, the efficiency could be enhanced by up to 49%. This high efficiency achieved in this study is dependent on the short pipe spacing of 5 cm and results in surface condensation on several occasions. Condensation on PSC has not been reported previously but should not pose a risk to road traffic because surface temperatures are above freezing.
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| 7. |
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| 8. |
- Johnsson, Josef, 1986
(author)
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Low temperature deicing of road infrastructure using renewable energy
- 2019
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Doctoral thesis (other academic/artistic)abstract
- Winter road maintenance is costly but it is inevitable since it is necessary to keep roads accessible and safe during winter. Current winter road maintenance methods use annually 600 000 tons of salt, in the Nordic countries. The salt ends up in the environment along the roads and results in environmental challenges. This thesis proposes an alternative, winter road maintenance concept for critical parts of the road infrastructure. The proposed concept consists of a hydronic heated pavement (HHP), utilised as pavement solar collector (PSC), which is connected to a borehole thermal energy storage (BTES). The combination of an HHP and a BTES means that the solar radiation will be harvested in the summer time and the stored energy will be used for winter road maintenance. This system can be installed at critical parts of a road infrastructure. In existing hydronic pavements district heating or other high temperature energy sources are currently used, however, high temperature energy sources limit the implementation of HHP systems. Research on using low temperature energy sources can result in a reduction of primary energy need and makes implementation of HHP systems more feasible. The purpose of this thesis is to investigate the feasibility of implementing hydronic heated pavements using renewable energy, in the Scandinavian countries. This manuscript presents the experimental and numerical results from a field station of BTES connected HHP system. The field station was constructed during 2017 and experiments on harvesting were conducted during the summer of 2018. The anti-icing and de-icing function of the HHP system were studied during the winter of 2018/2019. The results revealed that the solar efficiency of the HHP system reach as high as 42 % and 245 kWh/m2 of solar heat was harvested during the summer of 2018. This is a comparably high value for a pavement solar collector. The harvested energy were higher than the supplied heat (132 kWh/m2) during the following winter. However, the cold climate at the field station required supplementary heating since the BTES did not have the capacity to supply the required supply temperature of 7 degC to the HHP. The numerical simulations has reveald that by using a dew-point regulation and weather forecasting the energy consumption can be reduced by 62 % compared to a simple air temperature regulation. Based on the experimental and numerical results it can be concluded that it is feasible to design HHP systems to use low temperature (<10 degC) sources and at the same time achieve a substantial improvement of the surface conditions in a Scandinavian climate.
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| 9. |
- Johnsson, Josef, 1986, et al.
(author)
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Modeling the thermal performance of low temperature hydronic heated pavements
- 2019
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In: Cold Regions Science and Technology. - : Elsevier BV. - 0165-232X. ; 161, s. 81-90
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Journal article (peer-reviewed)abstract
- Winter road maintenance is costly but it is necessary in order to keep roads accessible and safe during winter. Current winter road maintenance methods use 600,000 tons of salt annually, in the Nordic countries. The salt ends up in the environment along the roads and results in environmental challenges. Alternative winter maintenance methods that use heat instead of salt are in use today. However, those systems are designed to use high temperature of about 20–35 °C. This paper presents a numerical model for designing low temperature (4–8 °C) hydronic heated pavements (HHP). The model is validated against an experimental setup and different control strategies are evaluated. The validation indicated that the developed model can predict the behavior of the HHP with a root mean square error (RMSE) <1.4 °C for surface temperatures and <0.4 °C for the return fluid. In this paper the model is used with two different control strategies. A basic strategy controlling the system based on air temperature and one strategy based on dew point temperature. With dew point regulation the energy consumption can be reduced by 62%. However, the energy consumption is still in the range of 125–180kWh/m 2 for the location of Östersund, Sweden. We found that the HHP system can utilize low temperature sources like waste energy or geothermal energy that is freely available. By using renewable energy for winter road maintenance, the environmental impact from winter road maintenance can be reduced.
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| 10. |
- Johnsson, Josef, 1986, et al.
(author)
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Modelling and evaluation of groundwater filled boreholes subjected to natural convection
- 2019
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In: Applied Energy. - : Elsevier BV. - 1872-9118 .- 0306-2619. ; 253
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Journal article (peer-reviewed)abstract
- One of the challenges of designing ground source heat pumps systems is the calculation of the effective thermal borehole resistance which affects the heat extraction rate and thereby the required length of the borehole. Calculating effective borehole resistance is especially demanding when the boreholes are filled with ground- water. The natural convection in the groundwater affects the heat transport from the borehole heat exchanger to the borehole wall. The objective of this paper is to present the results of the modified Pygfunction software in which recently developed correlations for calculating influence of the natural convection in boreholes has been incorporated. The calculated results were validated by using results of thermal response test (TRT) from four adjacent groundwater filled borehole in the central parts of Sweden. The numerical results reveal that the ori- ginal and unmodified Pygfunction can be used for accurate calculation of fluid temperatures in borehole heat exchangers by using an effective thermal conductivity of the filling material. However, that requires access to thermal response test data. The modified software calculates the effective borehole resistance with a deviation of about 15–30% compared to the effective borehole resistance from TRT. This deviation is an improvement compared with the standard assumption of neglecting natural convection in boreholes. However, for large in- stallations with more than 4000m of borehole heat exchangers a thermal response test is still recommended in order to ensure a more correct sizing of geothermal system.
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| 11. |
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| 12. |
- Johnsson, Josef, 1986
(author)
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Winter Road Maintenance using Renewable Thermal Energy
- 2017
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Licentiate thesis (other academic/artistic)abstract
- Winter road maintenance is costly but it is inevitable since it is necessary to keep roads accessible and safe during winter. Current winter road maintenance methods use annually 600 000 tons of salt, in the Nordic countries. The salt ends up in the environment along the roads and results in environmental challenges. This thesis proposes an alternative, winter road maintenance concept for critical parts of the road infrastructure. The proposed concept consists of a hydronic pavement (HP), utilised as solar collector, which is connected to a borehole thermal energy storage (BTES). The combination of an HP and a BTES (called renewable HP) means that the solar radiation will be harvested in the summer time and the stored energy will be used for winter road maintenance at critical parts of a road infrastructure. In existing hydronic pavements district heating or other high temperature energy sources are currently used, however, high temperature energy sources limit the implementation of HP systems. Research on using low temperature energy sources can result in a reduction of primary energy need and makes implementation of HP systems more feasible. The purpose of this thesis is to investigate the feasibility of implementing hydronic pavements using renewable energy, in the Scandinavian countries. This thesis studies how a BTES can be connected to a hydronic pavement, focusing on the design of the BTES. The studies are based on extensive literature reviews and numerical simulations considering the interaction between the hydronic pavement and the BTES. The studied systems have all been direct connected systems without supplementary heating such as boilers or heat pumps. The results revealed that BTES is a suitable thermal storage technology to be used in combination with renewable HP. The renewable HP systems are mostly suitable for areas with mild winters. For locations with harsher climates there is a need for supplementary heating or increased number of boreholes in the BTES. The studied locations of Tranarp and Studevannet revealed that the renewable HP system can reduce the annual number of hours with risk for ice formation from 400 hours and 855 hours, to 6 hours and 23 hours respectively. However, in order to reach low risk levels, further development of control systems will be needed.
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