scholarly journals A New Modeling Approach for Low-Carbon District Energy System Planning

Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1383
Author(s):  
Abolfazl Rezaei ◽  
Bahador Samadzadegan ◽  
Hadise Rasoulian ◽  
Saeed Ranjbar ◽  
Soroush Samareh Abolhassani ◽  
...  
Keyword(s):  
Heat Pump ◽  
Cooling System ◽  
Renewable Energy Sources ◽  
Energy Systems ◽  
Energy System ◽  
Heat Pumps ◽  
Piping System ◽  
Ground Source Heat Pumps ◽  
Electricity Cost ◽  
Heating And Cooling

Designing district-scale energy systems with renewable energy sources is still a challenge, as it involves modeling of multiple loads and many options to combine energy system components. In the current study, two different energy system scenarios for a district in Montreal/Canada are compared to choose the most cost-effective and energy-efficient energy system scenario for the studied area. In the first scenario, a decentral energy system comprised of ground-source heat pumps provides heating and cooling for each building, while, in the second scenario, a district heating and cooling system with a central heat pump is designed. Firstly, heating and cooling demand are calculated in a completely automated process using an Automatic Urban Building Energy Modeling System approach (AUBEM). Then, the Integrated Simulation Environment Language (INSEL) is used to prepare a model for the energy system. The proposed model provides heat pump capacity and the number of required heat pumps (HP), the number of photovoltaic (PV) panels, and AC electricity generation potential using PV. After designing the energy systems, the piping system, heat losses, and temperature distribution of the centralized scenario are calculated using a MATLAB code. Finally, two scenarios are assessed economically using the Levelized Cost of Energy (LCOE) method. The results show that the central scenario’s total HP electricity consumption is 17% lower than that of the decentral systems and requires less heat pump capacity than the decentral scenario. The LCOE of both scenarios varies from 0.04 to 0.07 CAD/kWh, which is cheaper than the electricity cost in Quebec (0.08 CAD/kWh). A comparison between both scenarios shows that the centralized energy system is cost-beneficial for all buildings and, after applying the discounts, the LCOE of this scenario decreases to 0.04 CAD/kWh.

scholarly journals Sizing and performance analyses of a combined heating and cooling system with the integration of short- and long-term storages

2021 ◽  
Vol 246 ◽  
pp. 07004
Author(s):  
Mohammad Shakerin ◽  
Vilde Eikeskog ◽  
Yantong Li ◽  
Harsem T. Thorgeir ◽  
Natasa Nord
Keyword(s):  
Heat Pump ◽  
Cooling System ◽  
Renewable Energy Sources ◽  
Energy System ◽  
Energy Sources ◽  
Heating And Cooling ◽  
Short And Long Term ◽  
Performance Analyses ◽  
And Performance

Technological advancements in the utilization of renewable energy sources have unveiled potentials for increasing building energy efficiency. Integrating heat pump-based energy systems with thermal storages is a suitable option to meet the thermal requirements of modern buildings and exploiting the available renewable energy sources. However, how to size the main components of a heat pump-based energy system with the integration of short- and long-term storages is not yet well explored. Therefore, this study focused on the design and performance analyses of an integrated heating and cooling system consist of a heat pump, borehole long-term thermal storage, and hot water tank short-term thermal. Heat pump models were introduced as parametric models based on the producer data. The dynamic thermal model of the energy system was developed and analysed in MATLAB. Different combinations of heating and cooling loads were tested. Integration of cooling and heating systems was discussed through different operation strategies and challenges were addressed. The results of the parametric analysis identified the key parameters affecting the design of components and efficiency of the system. Moreover, the results showed that lower cooling to heating load ratio leads to an excessive reduction of the ground temperature and overall efficiency over the long-term operation.

scholarly journals A methodology for designing decentralised energy systems with predictive control for heat pumps and thermal storage

2019 ◽  
Vol 111 ◽  
pp. 06014
Author(s):  
Andrew Lyden ◽  
Paul Tuohy
Keyword(s):  
Predictive Control ◽  
Thermal Characteristic ◽  
Thermal Characteristics ◽  
Energy Systems ◽  
Thermal Storage ◽  
Energy System ◽  
Heat Pumps ◽  
Hot Water ◽  
Water Tank ◽  
Electricity Cost

Decentralised energy systems provide the potential for adding energy system flexibility by separating demand/supply dynamics with demand side management and storage technologies. They also offer an opportunity for implementing technologies which enable sector coupling benefits, for example, heat pumps with controls set to use excess wind power generation. Gaps in this field relating to planning-level modelling tools have previously been identified: thermal characteristic modelling for thermal storage and advanced options for control. This paper sets out a methodology for modelling decentralised energy systems including heat pumps and thermal storage with the aim of assisting planning-level design. The methodology steps consist of: 1) thermal and electrical demand and local resource assessment methods, 2) energy production models for wind turbines, PV panels, fuel generators, heat pumps, and fuel boilers, 3) bi-directional energy flow models for simple electrical storage, hot water tank thermal storage with thermal characteristics, and a grid-connection, 4) predictive control strategy minimising electricity cost using a 24-hour lookahead, and 5) modelling outputs. Contributions to the identified gaps are examined by analysing the sensible thermal storage model with thermal characteristics and the use of the predictive control. Future extensions and applications of the methodology are discussed.

scholarly journals A European Database of Building Energy Profiles to Support the Design of Ground Source Heat Pumps

Energies ◽  
2019 ◽  
Vol 12 (13) ◽  
pp. 2496 ◽  
Author(s):  
Laura Carnieletto ◽  
Borja Badenes ◽  
Marco Belliardi ◽  
Adriana Bernardi ◽  
Samantha Graci ◽  
...  
Keyword(s):  
Heat Pump ◽  
Energy Demand ◽  
Residential Buildings ◽  
Building Energy ◽  
Heat Pumps ◽  
Climatic Conditions ◽  
Ground Source Heat Pumps ◽  
Heating And Cooling ◽  
Energy Profiles ◽  
Ground Source

The design of ground source heat pumps is a fundamental step to ensure the high energy efficiency of heat pump systems throughout their operating years. To enhance the diffusion of ground source heat pump systems, two different tools are developed in the H2020 research project named, “Cheap GSHPs”: A design tool and a decision support system. In both cases, the energy demand of the buildings may not be calculated by the user. The main input data, to evaluate the size of the borehole heat exchangers, is the building energy demand. This paper presents a methodology to correlate energy demand, building typologies, and climatic conditions for different types of residential buildings. Rather than envelope properties, three insulation levels have been considered in different climatic conditions to set up a database of energy profiles. Analyzing European climatic test reference years, 23 locations have been considered. For each location, the overall energy and the mean hourly monthly energy profiles for heating and cooling have been calculated. Pre-calculated profiles are needed to size generation systems and, in particular, ground source heat pumps. For this reason, correlations based on the degree days for heating and cooling demand have been found in order to generalize the results for different buildings. These correlations depend on the Köppen–Geiger climate scale.

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 BUILDINGS DESIGN INTEGRATION WITH GEOTHERMAL ENERGY SYSTEM TECHNOLOGIES AND AIR CONDITIONING APPLICATIONS

2020 ◽  
Vol 1 (2) ◽  
Author(s):  
Abeer Osama Radwan
Keyword(s):  
Geothermal Energy ◽  
Influence Factors ◽  
Energy System ◽  
Heat Pumps ◽  
Ground Source Heat Pumps ◽  
Human Thermal Comfort ◽  
Heating And Cooling ◽  
Ground Source ◽  
Modern Cities ◽  
Design Integration

Nowadays global warming and thermal islands in modern cities are spending much energy on heating and cooling spaces. Geothermal energy considered a renewable energy technology for space heating and cooling. The ground source heat pumps (GSHPs) are increasingly interested in their expressive potential to reduce fossil fuel consumption and hence reduce greenhouse gases. Geothermal energy used for both electricity generation and direct use, depending on the temperature and the chemistry of the resources. Recently, direct utilization has varied significantly, and there are several methods available for temperatures typically ranging from 4°C up to 80°C. (Lund J.W., 2012). This paper presents a comprehensive literature-based review of ground source heat pump technology, cooling, and heating applications buildings to achieve precisely human thermal comfort. Subsequently, propose the influence factors of the system components that would undoubtedly reflect on the optimal design of the building. As a result, achieve precisely an integrated building.

scholarly journals An Approach to Short-Term Control of Integrated Energy Systems with Load-Controlled Consumers

2019 ◽  
Vol 217 ◽  
pp. 01001
Author(s):  
Valery Stennikov ◽  
Evgeny Barakhtenko ◽  
Oleg Voitov
Keyword(s):  
Storage Systems ◽  
Energy Systems ◽  
Electric Heating ◽  
Energy System ◽  
Heat Pumps ◽  
Short Term ◽  
Integrated Energy Systems ◽  
Heating And Cooling ◽  
Functional Features ◽  
Heat Loads

Modern cities and industrial centers boast a developed energy infrastructure including fuel, electric, heating, and cooling systems. The integration of many separate system into a single technological complex can provide new functional capabilities, the application of more advanced technologies for operation, and the establishment of integrated energy systems. Such systems have a multidimensional structure of functional features and properties of development. The control of integrated energy systems with load-controlled consumers represents an urgent and a rather challenging task. The paper is concerned with an approach to short-term control of integrated energy systems with load-controlled consumers. Planning the daily electricity and heat loads is performed for an integrated energy system, including energy storage systems and electric water heaters, electrical shiftable loads of individual consumers as well as power generation by additional electricity and heat sources (PV systems, wind turbines, heat pumps). The optimal daily profiles are obtained based on the initial profiles of electricity and heat loads, photovoltaic generation and optimal profiles of using electricity and heat storage systems and shiftable load. Optimal daily electricity and heat load profiles differ greatly from the initial ones, which provides a reduction in the energy costs for the consumer.

scholarly journals District Power-To-Heat/Cool Complemented by Sewage Heat Recovery

Energies ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 364 ◽  
Author(s):  
Marcello Aprile ◽  
Rossano Scoccia ◽  
Alice Dénarié ◽  
Pál Kiss ◽  
Marcell Dombrovszky ◽  
...  
Keyword(s):  
Heat Exchanger ◽  
Heat Pump ◽  
Heat Recovery ◽  
Renewable Energy Sources ◽  
District Heating ◽  
Heat Pumps ◽  
Economic Feasibility ◽  
Operational Experience ◽  
Operational Parameters ◽  
Heating And Cooling

District heating and cooling (DHC), when combined with waste or renewable energy sources, is an environmentally sound alternative to individual heating and cooling systems in buildings. In this work, the theoretical energy and economic performances of a DHC network complemented by compression heat pump and sewage heat exchanger are assessed through dynamic, year-round energy simulations. The proposed system comprises also a water storage and a PV plant. The study stems from the operational experience on a DHC network in Budapest, in which a new sewage heat recovery system is in place and provided the experimental base for assessing main operational parameters of the sewage heat exchanger, like effectiveness, parasitic energy consumption and impact of cleaning. The energy and economic potential is explored for a commercial district in Italy. It is found that the overall seasonal COP and EER are 3.10 and 3.64, while the seasonal COP and EER of the heat pump alone achieve 3.74 and 4.03, respectively. The economic feasibility is investigated by means of the levelized cost of heating and cooling (LCOHC). With an overall LCOHC between 79.1 and 89.9 €/MWh, the proposed system can be an attractive solution with respect to individual heat pumps.

Development of design guidelines for thermo-active foundations

2017 ◽  
Vol 27 (6) ◽  
pp. 805-817 ◽  
Author(s):  
Byung C. Kwag ◽  
Moncef Krarti
Keyword(s):  
Heat Pump ◽  
Heat Pumps ◽  
Design Guidelines ◽  
Conventional Heating ◽  
Ground Source Heat Pump ◽  
External Energy ◽  
Geothermal Heat ◽  
Ground Source Heat Pumps ◽  
Heating And Cooling ◽  
Ground Source

Ground medium can be utilized as a direct energy source to heat and cool buildings. In particular, ground source heat pump systems take advantage of the year-round mild deep earth temperature without a significant reliance on any external energy sources. However, the high installation cost of ground source heat pumps associated with high drilling cost of vertical boreholes often make these systems less cost-effective compared to conventional heating and cooling systems. Thermo-active foundations can be a viable solution to reduce ground source heat pump high installation costs by embedding heat exchangers within building foundation structures. Compared to ground source heat pumps, only limited analyses and research studies have been reported for thermo-active foundations especially for the US climates. In particular, no specific design guidelines have been reported for thermo-active foundations especially for US climates. In this paper, a simplified design approach was developed and applied for specifying geothermal heat pump size and heat exchanger loop length to meet all or part of building heat and cooling thermal loads. The developed guidelines would thus provide a proper design guide for installation of thermo-active foundations for heating and cooling of both US residential and commercial buildings.

scholarly journals Geothermal energy: shallow sources

2014 ◽  
Vol 126 (2) ◽  
pp. 25
Author(s):  
Ian Johnston
Keyword(s):  
Heat Pump ◽  
Geothermal Energy ◽  
Heat Pumps ◽  
Cooling Mode ◽  
Ground Source Heat Pumps ◽  
Heating And Cooling ◽  
Ground Source ◽  
Heating Mode ◽  
To Receive ◽  
Ground Energy

Below a depth of around 5 to 8 metres below the surface, the ground displays a temperature which is effectively constant and a degree or two above the weighted mean annual air temperature at that particular location. In Melbourne, the ground temperature at this depth is around 18°C with temperatures at shallower depths varying according the season. Further north, these constant temperatures increase a little; while for more southern latitudes, the temperatures are a few degrees cooler. Shallow source geothermal energy (also referred to as direct geothermal energy, ground energy using ground source heat pumps and geoexchange) uses the ground and its temperatures to depths of a few tens of metres as a heat source in winter and a heat sink in summer for heating and cooling buildings. Fluid (usually water) is circulated through a ground heat exchanger (or GHE, which comprises pipes built into building foundations, or in specifically drilled boreholes or trenches), and back to the surface. In heating mode, heat contained in the circulating fluid is extracted by a ground source heat pump (GSHP) and used to heat the building. The cooled fluid is reinjected into the ground loops to heat up again to complete the cycle. In cooling mode, the system is reversed with heat taken out of the building transferred to the fluid which is injected underground to dump the extra heat to the ground. The cooled fluid then returns to the heat pump to receive more heat from the building.

scholarly journals Residential Buildings’ Foundations as a Ground Heat Exchanger and Comparison among Different Types in a Moderate Climate Country

Energies ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 6287
Author(s):  
Lazaros Aresti ◽  
Paul Christodoulides ◽  
Gregoris P. Panayiotou ◽  
Georgios Florides
Keyword(s):  
Residential Buildings ◽  
Residential Building ◽  
Energy Systems ◽  
Heat Pumps ◽  
Coefficient Of Performance ◽  
Software Environment ◽  
Ground Source Heat Pumps ◽  
Ground Heat Exchangers ◽  
Heating And Cooling ◽  
Air Source Heat Pump

Shallow Geothermal Energy Systems (SGESs) constitute Renewable Energy Systems (RES), which find application in the residential sector through the use of Ground Source Heat Pumps (GSHPs). GSHPs are associated with Ground Heat Exchangers (GHEs), whereby heat is gained/lost through a network of tubes into the ground. GSHPs have failed to flourish in the RES market due to their high initial costs and long payback periods. In this study, the use of Energy Geo-Structure (EGS) systems, namely, the foundation (or energy) piles and the foundation bed of a residential building in Cyprus, was computationally modeled in the COMSOL Multiphysics software. First, the single-houses’ trend in number of units and area in Cyprus was examined and a theoretically typical house with nearly Zero Energy Building (nZEB) characteristics was considered. The heating and cooling loads were estimated in the TRNSYS software environment and used as inputs to investigate the performance of the GSHP/GHE systems. Both systems were shown to exhibit steady performance and high Coefficient of Performance (COP) values, making them an alternative RES solution for residential building integration. Next, the systems were economically evaluated through a comparison with a convectional Air Source Heat Pump (ASHP) system. The economic analysis showed that the cost of the suggested conversions of the foundation elements into GHEs had short payback periods. Consequently, either using the foundation piles or bed as a GHE is a profitable investment and an alternative to conventional RES.

Sign in / Sign up

Export Citation Format

Share Document