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

Materials ◽  
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.

scholarly journals Clean Energy for Cooling and Heating with Ground Source Heat Pumps

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.

scholarly journals Sílice Mesoporosa como encapsulador de materiales de cambio de fase (PCM)

2019 ◽  
pp. 14-19 ◽  
Author(s):  
Nancy González-Cervantes ◽  
Mercedes Salazar-Hernández ◽  
Miroslava Cano-Lara ◽  
Carmen Salazar-Hernández
Keyword(s):  
Thermal Stability ◽  
Renewable Energy ◽  
Energy Storage ◽  
Phase Change ◽  
Phase Change Materials ◽  
Renewable Energy Sources ◽  
Energy Sources ◽  
Research Topics ◽  
Solar Energy Storage ◽  
High Latent Heat

Today, the effective renewable energy sources are research topics, with direct solar radiation being one of the best sources of energy. However, the use of this form of energy is optimized with the development of technologies for storage (TES). One of the proposed techniques for solar energy storage is the application of phase change materials (PCMs). Several candidates of phase change materials such as organic and inorganic and their mixtures have been proposed as energy storage because they have a high latent heat. However, a disadvantage of these materials is their decomposition during storage and energy release cycles, therefore, in this project it is proposed to encapsulate PCMs in mesoporous silica networks in order to increase thermal stability.

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

Proceedings ◽  
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.

scholarly journals Impact of location characteristics on renewable energy production for a group of buildings

2019 ◽  
Vol 116 ◽  
pp. 00084
Author(s):  
Krystian Szczerbak
Keyword(s):  
Renewable Energy ◽  
Heat Pump ◽  
Energy Demand ◽  
Renewable Energy Sources ◽  
Heat Pumps ◽  
Hot Water ◽  
Energy Sources ◽  
Solar Collectors ◽  
Single Family ◽  
Northern Regions

The climate in Poland is slightly disparate in each region. The differences in temperature not always come along with the intensity of solar radiation in 5 climate zones. South of the country is colder, but well irradiated by the Sun and northern regions have milder climate, but are less irradiated. This fact alone makes people consider the suitability and safety of using renewable energy sources such as air-to-water heat pumps, solar collectors and photovoltaics instead of more traditional, fossil fuel powered sources. This paper presents a comparison analysis of energy demand and the cost for heating in a group of single-family buildings by 4 variants (gas boiler, gas boiler and solar collectors, air-to-water heat pump, air-to-water heat pump and photovoltaics) in 5 chosen cities in each polish climate zone. Calculations were done for space heating and domestic hot water energy demand, CO2 emissions and cumulative costs for all variants and locations. The results confirm the inconsistency of polish climate and have shown profitability and utility of renewable energy sources.

scholarly journals Geoexchanger System for Buildings Heating and Cooling

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.

scholarly journals Sustainable Development and Renewable Energy Sectors: Selected Indicators in European Union and Poland

2018 ◽  
Vol 18(33) (4) ◽  
pp. 250-258
Author(s):  
Anna Klepacka
Keyword(s):  
European Union ◽  
Renewable Energy ◽  
Raw Materials ◽  
Renewable Energy Sources ◽  
Main Tool ◽  
Heat Pumps ◽  
Solar Heating ◽  
Energy Sources ◽  
The European Union ◽  
European Union Countries

The aim of this article was to show the position of Poland in the renewable energy subsectors among the European Union countries. The research covered the areas of biomass, solar heating and heat pumps, showing the degree of their utilization, power required to drive the system and their production in 2016. The provided information was supplemented with a revenues per employee in thousand euros in chosen subsectors of renewable energy sources in the year 2016. The main tool for carrying out the set objective was the use of descriptive and comparative methods. The results of the survey demonstrated Poland’s prominent place in the sector of liquid biofuels (1st place in EU), thanks to the significant supply of raw materials as well as development perspectives in solar energy, which is confirmed by the world's statistics indicating a record number of photovoltaic installations fitted (PV).

scholarly journals The effect of metal wool on the charging and discharging rate of the phase transition thermal storage material

2021 ◽  
Vol 4 (5(112)) ◽  
pp. 12-20
Author(s):  
Olga Khliyeva ◽  
Vitaly Zhelezny ◽  
Aleksey Paskal ◽  
Yana Hlek ◽  
Dmytro Ivchenko
Keyword(s):  
Power Systems ◽  
Phase Change ◽  
Phase Change Materials ◽  
Thermal Storage ◽  
Heating Time ◽  
Phase Changes ◽  
Storage Material ◽  
Heat Accumulation ◽  
Heating And Cooling ◽  
Efficiency And Reliability

Thermal energy storage (TES) plays an important role in solar heat power systems. The use of phase change materials (PCM) and selecting additives to increase the rate of heat accumulation is a promising way to increase the efficiency and reliability of such systems. The objects of the study were pure paraffin wax (PW) and composite PCMs based on it (containing aluminum and copper wool of 30 and 45 μm in diameter, respectively). An experimental setup with a cylindrical measuring cell was created, which was also considered as a model of a capsule with a thermal storage material. The rate of temperature change in the pure PW sample and samples of composite PCMs was experimentally measured. Two modes of heating and cooling were investigated: from 48 to 59 °C (mode with a phase change) and from 30 to 40 °C (mode without phase changes). Heating time from 48 to 59 °C for the PW sample was 13 min., for the PW samples with the content of aluminum wool of 0.00588 and 0.01780 m3·m-3 − 11 and 10.5 min., for the PW samples with the content of copper wool of 0.00524 and 0.01380 m3·m-3 − 11 and 8 min., correspondingly. The minimum heating time from 30 to 40 °C was 6 min. for the sample of PW with 0.01380 m3·m-3 of copper wool in comparison with 9 min. for the sample of pure PW. The expediency of using copper wool as an additive to thermal storage materials of PW to increase the charging and discharging rate of TES devices without significantly raising their price was confirmed. The presence of metal wool in molten PW suppresses bottom-up convective currents, so the main mechanism of heat transfer is thermal conductivity. This fact will contribute to a faster equalization of the temperature field by the height of heat storage capsules

scholarly journals Water-air regenerative heat exchanger with increased heat exchange efficiency

2021 ◽  
Vol 295 ◽  
pp. 04005
Author(s):  
Sergey Batukhtin ◽  
Andrey Batukhtin ◽  
Marina Baranovskaya
Keyword(s):  
Renewable Energy ◽  
Solar Energy ◽  
Solar Collector ◽  
Renewable Energy Sources ◽  
Thermal Power ◽  
Economic Effect ◽  
Hot Water ◽  
Energy Sources ◽  
Water Supply Systems ◽  
Regenerative Heat

According to experts’ forecasts, by 2040 the global demand for energy will increase by 37%, and renewable energy sources in the next 20 years will become the fastest growing segment of the world energy, their share in the next decade will grow by about one and a half times. Solar energy is the fastest growing industry among all non-conventional energy sources and is gaining the highest rates of development in comparison with other renewable energy sources. In this article, the authors provide an overview of the technologies that increase the efficiency and productivity of solar panels, only the investigated methods are described that can speed up the process of introducing solar energy instead of traditional. All the methods described can increase the efficiency of systems that are based on the use of the sun as the main source of energy. The authors presented and described the scheme of a solar-air thermal power plant, which will improve energy efficiency through the use of a regenerative air solar collector with increased heat transfer efficiency. Strengthening will be achieved through the use of hemispherical depressions on the surface that receives solar radiation. A schematic diagram is given and the principle of operation of such a solar collector is described in detail. A comparative calculation of the intensification of the solar collector with the use of depressions and without the use as modernization was carried out, on the basis of which a conclusion was made about the efficiency of using this type of solar collector and the economic effect from the application of this method. A description of the method for calculating the solar collector is given, thanks to which this development can be used and implemented in existing heating and hot water supply systems.

Sign in / Sign up

Export Citation Format

Share Document