Utilizing Asphalt Heat Energy in Finnish Climate Conditions

Anne Mäkiranta; Erkki Hiltunen

doi:10.3390/en12112101

Utilizing Asphalt Heat Energy in Finnish Climate Conditions

Energies ◽

10.3390/en12112101 ◽

2019 ◽

Vol 12 (11) ◽

pp. 2101 ◽

Cited By ~ 1

Author(s):

Anne Mäkiranta ◽

Erkki Hiltunen

Keyword(s):

Renewable Energy ◽

Temperature Difference ◽

Heat Pumps ◽

Heat Energy ◽

Distributed Temperature Sensing ◽

Frozen Ground ◽

Climate Conditions ◽

Difference Curve ◽

Heating And Cooling ◽

The Difference

Geothermal energy is a form of renewable energy, which offers carbon-free solutions for heating and cooling spaces. This study evaluates the use of renewable asphalt heat energy in frozen ground conditions. Asphalt heat energy can be harnessed using a low-energy network, heat collection pipes and heat pumps. This study measured temperatures under the asphalt layer during a three-year period between 2014 and 2017. Measurements were made using a distributed temperature sensing method based on light scattering. Temperatures taken at four different depths under the asphalt (0.5 m, 1.0 m, 3.0 m and 10 m) are presented here. These temperatures are compared with that detected at the depth at which the temperature remains constant all year round. The temperature difference curve between 0.5 m depth and the constant soil temperature depth indicates that from April to October the soil at 0.5 m depth is warming and the temperature difference is positive, even as much as 18 °C. Instead, at the 3.0 m depth, the difference curve is smoother and it varies only from −5 to +5 °C. It is positive from June to November. The surface layer (0 m–1.0 m) is suitable for harvesting heat that can be stored in a deeper (1.5 m–3.0 m) purpose-built storage or in a bedrock heat battery. The calculated heat capacities indicate that asphalt energy, because of high temperatures, is a noteworthy renewable energy source.

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Clean Energy for Cooling and Heating with Ground Source Heat Pumps

Advances in Nanoscience and Nanotechnology ◽

10.33140/ann.03.02.5 ◽

2019 ◽

Vol 3 (2) ◽

Keyword(s):

Renewable Energy ◽

Alternative Energy ◽

Renewable Energy Sources ◽

Clean Energy ◽

Heat Pumps ◽

Hot Water ◽

Energy Sources ◽

Ground Source Heat Pumps ◽

Heating And Cooling ◽

Ground Source

In the recent attempts to stimulate alternative energy sources for heating and cooling of buildings, emphasise has been put on utilisation of the ambient energy from ground source heat pump systems (GSHPs) and other renewable energy sources. Exploitation of renewable energy sources and particularly ground heat in buildings can significantly contribute towards reducing dependency on fossil fuels. The study was carried out at the Energy Research Institute (ERI), between September 2016 and November 2017. This paper highlights the potential energy saving that could be achieved through use of ground energy source. The main concept of this technology is that it uses the lower temperature of the ground (approximately <32°C), which remains relatively stable throughout the year, to provide space heating, cooling and domestic hot water inside the building area. The purpose of this study, however, is to examine the means of reducing of energy consumption in buildings, identifying GSHPs as an environmental friendly technology able to provide efficient utilisation of energy in the buildings sector, promoting the use of GSHPs applications as an optimum means of heating and cooling, and presenting typical applications and recent advances of the DX GSHPs. It is concluded that the direct expansion of GSHP are extendable to more comprehensive applications combined with the ground heat exchanger in foundation piles and the seasonal thermal energy storage from solar thermal collectors. This study highlights the energy problem and the possible saving that can be achieved through the use of the GSHP systems. This article discusses the principle of the ground source energy, varieties of GSHPs, and various developments.

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The Efficiency of Geothermal Heat Pumps With Vertical Ground Heat Exchangers: A Simulation Under Iraqi Conditions

ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis, Volume 1 ◽

10.1115/esda2010-24373 ◽

2010 ◽

Author(s):

Nazar F. Antwan ◽

Iyd E. Maree

Keyword(s):

Heat Exchangers ◽

Energy Savings ◽

Heat Pumps ◽

Domestic Water ◽

Geothermal Heat ◽

Local Climate ◽

Climate Conditions ◽

The North ◽

Heating And Cooling ◽

Ground Source

Geothermal heat pumps with ground source heat exchangers have been widely used for heating and cooling homes as well as for domestic water heating. A study on a small house in Erbil-Iraq was conducted to assess energy savings when using GHPs with closed loop ground source heat exchangers as compared with air-to-air heat pumps. Local climate conditions and soil properties of Erbil located in the north of Iraq were used. The simulation was performed using TRNSYS-16 software. The results of this study show that we can reduce the energy used for heating and cooling by 39% during annual when using GHP. The simulation also showed that the average COP for heating is 2.9 and for cooling is 2.6 when using air to air heat pumps and the average COP for heating is 5.6 and 3.6 for cooling when using GHP. This reduction in energy reduces the CO2 emission as it reduces energy consumption.

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The Advisability of Employment of Renewable Energy Sources in DHW Systems in the Kindergarten

Proceedings ◽

10.3390/proceedings2019016041 ◽

2019 ◽

Vol 16 (1) ◽

pp. 41

Author(s):

Dorota Anna Krawczyk ◽

Antonio Rodero ◽

Agata Witkowska ◽

Bernadetta Wądołowska

Keyword(s):

Renewable Energy ◽

Renewable Energy Sources ◽

Heat Pumps ◽

Hot Water ◽

Coefficient Of Performance ◽

Energy Sources ◽

Solar Collectors ◽

Payback Time ◽

Heat Demand ◽

The Difference

This research aims to show the advisability of usage of selected renewable energy sources for domestic hot water (DHW) installations in buildings located in Poland and Spain. The analysis was conducted for a typical kindergarten, an example of buildings with high density of people and stable profile of usage, as opposed to schools which are closed during summer holidays. We took into account national regulations to estimate heat demand. Then applying solar collectors and heat pumps to use as a monovalent energy sources were considered. The total cost of the system with solar collectors in Poland was found to be 1.4 times higher than in Spain, whereas the difference in a case of air heat pumps was 18%. Moreover efficiency of solar collector and heat pump systems were found as 49.56% for Warsaw, 52.29% for Madrid with coefficient of performance (COP) 2.2 and 2.55 respectively, therefore simple payback time (SPBT) of investment was estimated in a range between 6–12 years for solar collectors and 5–6 years for heat pumps.

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Energy Recovery from Wastewater: A Study on Heating and Cooling of a Multipurpose Building with Sewage-Reclaimed Heat Energy

Sustainability ◽

10.3390/su12010116 ◽

2019 ◽

Vol 12 (1) ◽

pp. 116 ◽

Cited By ~ 3

Author(s):

Daniele Cecconet ◽

Jakub Raček ◽

Arianna Callegari ◽

Petr Hlavínek

Keyword(s):

Heat Exchangers ◽

Urban Areas ◽

Energy Recovery ◽

Heat Recovery ◽

Energy Requirement ◽

Heat Pumps ◽

Heat Energy ◽

Heating And Cooling ◽

Conventional Solution ◽

The Impact

To achieve technically-feasible and socially-desirable sustainable management of urban areas, new paradigms have been developed to enhance the sustainability of water and its resources in modern cities. Wastewater is no longer seen as a wasted resource, but rather, as a mining ground from which to obtain valuable chemicals and energy; for example, heat energy, which is often neglected, can be recovered from wastewater for different purposes. In this work, we analyze the design and application of energy recovery from wastewater for heating and cooling a building in Brno (Czech Republic) by means of heat exchangers and pumps. The temperature and the flow rate of the wastewater flowing in a sewer located in the proximity of the building were monitored for a one-year period, and the energy requirement for the building was calculated as 957 MWh per year. Two options were evaluated: heating and cooling using a conventional system (connected to the local grid), and heat recovery from wastewater using heat exchangers and coupled heat pumps. The analysis of the scenarios suggested that the solution based on heat recovery from wastewater was more feasible, showing a 59% decrease in energy consumption compared to the conventional solution (respectively, 259,151 kWh and 620,475 kWh per year). The impact of heat recovery from wastewater on the kinetics of the wastewater resource recovery facility was evaluated, showing a negligible impact in both summer (increase of 0.045 °C) and winter conditions (decrease of 0.056 °C).

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Reuse of heat energy in wastewater: implementation examples in Japan

Water Science & Technology ◽

10.2166/wst.2001.0640 ◽

2001 ◽

Vol 43 (10) ◽

pp. 277-285 ◽

Cited By ~ 57

Author(s):

N. Funamizu ◽

M. Iida ◽

Y. Sakakura ◽

T. Takakuwa

Keyword(s):

Wastewater Reuse ◽

Heat Pumps ◽

Heat Energy ◽

Sewerage System ◽

Melting Snow ◽

Heat Transfer Efficiency ◽

Technical Developments ◽

Heating And Cooling ◽

Key Factor ◽

Large Heat

Sewage and treated water can be a heat source in urban area due to large heat capacity, thus recovery and reuse of its energy is one of the most desirable plans for the sewerage system. In this paper, characteristics of heat energy in wastewater, reuse plans, and some experiences in Japan are presented. Full-scale reuse projects for heating and cooling in the Tokyo Metropolitan Districts and project for melting snow in Sapporo City are discussed. The key factors found in experience of Tokyo were setting the heat pumps near the demand points and the technical developments of equipment to prevent system from clogging, corrosion, and decrease in the heat transfer efficiency. It was also found through the project for melting snow in Sapporo that the key factor in public acceptance was the multi-purpose use of the sewerage system both for melting snow in winter and retaining rain water in summer.

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Phase-Change Materials in Hydronic Heating and Cooling Systems: A Literature Review

Materials ◽

10.3390/ma13132971 ◽

2020 ◽

Vol 13 (13) ◽

pp. 2971

Author(s):

Rok Koželj ◽

Eneja Osterman ◽

Fabrizio Leonforte ◽

Claudio Del Pero ◽

Alessandro Miglioli ◽

...

Keyword(s):

Renewable Energy ◽

Phase Change ◽

Phase Change Materials ◽

Renewable Energy Sources ◽

Thermal Storage ◽

Heat Pumps ◽

Hot Water ◽

Energy Sources ◽

Practical Implementation ◽

Heating And Cooling

When considering the deployment of renewable energy sources in systems, the challenge of their utilization comes from their time instability when a mismatch between production and demand occurs. With the integration of thermal storages into systems that utilize renewable energy sources, such mismatch can be evened out. The use of phase-change materials (PCMs) as thermal storage has a theoretical advantage over the sensible one because of their high latent heat that is released or accumulated during the phase-change process. Therefore, the present paper is a review of latent thermal storages in hydronic systems for heating, cooling and domestic hot water in buildings. The work aims to offer an overview on applications of latent thermal storages coupled with heat pumps and solar collectors. The review shows that phase-change materials improve the release of heat from thermal storage and can supply heat or cold at a desired temperature level for longer time periods. The PCM review ends with the results from one of the Horizon2020 research projects, where indirect electrical storage in the form of thermal storage is considered. The review is a technological outline of the current state-of-the-art technology that could serve as a knowledge base for the practical implementation of latent thermal storages. The paper ends with an overview of energy storage maturity and the objectives from different roadmaps of European bodies.

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Geoexchanger System for Buildings Heating and Cooling

International Journal of Nanotechnology and Nanomedicine ◽

10.33140/ijnn/02/01/00006 ◽

2017 ◽

Vol 2 (1) ◽

Keyword(s):

Renewable Energy ◽

Energy Consumption ◽

Alternative Energy ◽

Heat Pumps ◽

Hot Water ◽

Energy Sources ◽

Direct Expansion ◽

Ground Source Heat Pumps ◽

Heating And Cooling ◽

Ground Source

Geothermal heat pumps (GSHPs), or direct expansion (DX) ground source heat pumps, are a highly efficient renewable energy technology, which uses the earth, groundwater or surface water as a heat source when operating in heating mode or as a heat sink when operating in a cooling mode. It is receiving increasing interest because of its potential to reduce primary energy consumption and thus reduce emissions of the greenhouse gases (GHGs). The main concept of this technology is that it utilises the lower temperature of the ground (approximately <32°C), which remains relatively stable throughout the year, to provide space heating, cooling and domestic hot water inside the building area. The main goal of this study is to stimulate the uptake of the GSHPs. Recent attempts to stimulate alternative energy sources for heating and cooling of buildings has emphasised the utilisation of the ambient energy from ground source and other renewable energy sources. The purpose of this study, however, is to examine the means of reduction of energy consumption in buildings, identify GSHPs as an environmental friendly technology able to provide efficient utilisation of energy in the buildings sector, promote using GSHPs applications as an optimum means of heating and cooling, and to present typical applications and recent advances of the DX GSHPs. The study highlighted the potential energy saving that could be achieved through the use of ground energy sources. It also focuses on the optimisation and improvement of the operation conditions of the heat cycle and performance of the DX GSHP. It is concluded that the direct expansion of the GSHP, combined with the ground heat exchanger in foundation piles and the seasonal thermal energy storage from solar thermal collectors, is extendable to more comprehensive applications.

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