Sustainable energy solutions for thermal load in buildings - Role of heat pumps, solar thermal, and hydrogen-based cogeneration systems

Author(s):  
Praveen Cheekatamarla ◽  
Vishaldeep Sharma ◽  
Bo Shen

Abstract Economic and population growth is leading to increased energy demand across all sectors – buildings, transportation, and industry. Adoption of new energy consumers such as electric vehicles could further increase this growth. Sensible utilization of clean renewable energy resources is necessary to sustain this growth. Thermal needs in a building pose a significant challenge to the energy infrastructure. Supporting the current and future building thermal energy needs to offset the total electric demand while lowering the carbon footprint and enhancing the grid flexibility is presented in this study. Performance assessment of heat pumps, renewable energy, non-fossil fuel-based cogeneration systems, and their hybrid configurations was conducted. The impact of design configuration, coefficient of performance (COP), electric grid's primary energy efficiency on the key attributes of total carbon footprint, life cycle costs, operational energy savings, and site-specific primary energy efficiency are analyzed and discussed in detail.

2018 ◽  
Vol 70 ◽  
pp. 01001
Author(s):  
Jacek Biskupski

This paper gives a thorough description of the two different scenarios of retrofit of an existing detached country house (with high primary energy demand) to a net zero energy building (nZEB) or near zero energy (nearZEB) by using energy form on-site RES. Using a designed piece of modelling software author pointed out two possible solutions. First one, based on a bio boiler and small on-site PV generator (on-grid) and the other based on large PV generator and three heat pumps. A 24 months test was performed in order to find out the output of both scenarios. In first period, the bio boiler delivered energy for space heating and DHW, while energy from PV was used to cover all electricity needs of the household during the 12 months testing period. In the later, the energy received from 10 kWp PV of was partly used to cover the current needs of the entire household (switchable on/off-grid system), and surplus was stored in the national electricity grid and regained later in the winter for the space heating (by a GSHP) and ventilation (ASHP) and DHW (dedicated ASHP). In both cases the system proofed the possibility to achieve the nZEB (nearZEB in first scenario) state of the household, as all (in the first near all) energy needs were covered by renewable energy produced on-site.


2020 ◽  
Vol 1 (1) ◽  
pp. 33-47
Author(s):  
Tran Viet Dung

AbstractVietnam has experienced an economic growth accompanied by increasing energy demand and inadequate supplies. Like most developing countries, the increased inefficient use of energy in Vietnam leads to increased greenhouse gas emissions and high energy costs for consumers. Also, the traditional sources of energy are not sufficient to satisfy the demand of the economic sectors.With the negative impact of climate change on water resources and the depletion of coal, oil and gas reserves, Vietnam must diversify and integrate other forms of renewable energies into its energy mix. The efficient use of renewable energy resources can boost economic development. Thus, the policies for endorsing renewable energies and energy efficiency are playing a vital role in ensuring the sustainable development for Vietnam’s future. This paper examines the legal and policy framework influencing the deployment of renewable energies and energy efficiency in Vietnam. The paper also attempts to identify major barriers to a large scale deployment of renewable energies and energy efficiency technologies and offers some possible solutions.


2016 ◽  
Vol 23 (1) ◽  
pp. 21-35
Author(s):  
Janusz S. Szmyd

Abstract The development of civilisation is linked inextricably with growing demand for electricity. Thus, the still-rapid increase in the level of utilisation of natural resources, including fossil fuels, leaves it more and more urgent that conventional energy technologies and the potential of the renewable energy sources be made subject to re-evaluation. It is estimated that last 200 years have seen use made of more than 50% of the available natural resources. Equally, if economic forecasts prove accurate, for at least several more decades, oil, natural gas and coal will go on being the basic primary energy sources. The alternative solution represented by nuclear energy remains a cause of considerable public concern, while the potential for use to be made of renewable energy sources is seen to be very much dependent on local environmental conditions. For this reason, it is necessary to emphasise the impact of research that focuses on the further sharpening-up of energy efficiency, as well as actions aimed at increasing society’s awareness of the relevant issues. The history of recent centuries has shown that rapid economic and social transformation followed on from the industrial and technological revolutions, which is to say revolutions made possible by the development of power-supply technologies. While the 19th century was “the age of steam” or of coal, and the 20th century the era of oil and gas, the question now concerns the name that will at some point come to be associated with the 21st century. In this paper, the subjects of discussion are primary energy consumption and energy resources, though three international projects on the global scale are also presented, i.e. ITER, Hydrates and DESERTEC. These projects demonstrate new scientific and technical possibilities, though it is unlikely that commercialisation would prove feasible before 2050. Research should thus be focused on raising energy efficiency. The development of high-efficiency technologies that reinforce energy security is presented, with it being assumed that these new high-efficiency technologies are capable of being applied globally in the near future.


Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1012
Author(s):  
Francesco Calise ◽  
Francesco L. Cappiello ◽  
Maria Vicidomini ◽  
Jian Song ◽  
Antonio M. Pantaleo ◽  
...  

In this research, a technoeconomic comparison of energy efficiency options for energy districts located in different climatic areas (Naples, Italy and Fayoum, Egypt) is presented. A dynamic simulation model based on TRNSYS is developed to evaluate the different energy efficiency options, which includes different buildings of conceived districts. The TRNSYS model is integrated with the plug-in Google SketchUp TRNSYS3d to estimate the thermal load of the buildings and the temporal variation. The model considers the unsteady state energy balance and includes all the features of the building’s envelope. For the considered climatic zones and for the different energy efficiency measures, primary energy savings, pay back periods and reduced CO2 emissions are evaluated. The proposed energy efficiency options include a district heating system for hot water supply, air-to-air conventional heat pumps for both cooling and space heating of the buildings and the integration of photovoltaic and solar thermal systems. The energy actions are compared to baseline scenarios, where the hot water and space heating demand is satisfied by conventional natural gas boilers, the cooling demand is met by conventional air-to-air vapor compression heat pumps and the electric energy demand is satisfied by the power grid. The simulation results provide valuable guidance for selecting the optimal designs and system configurations, as well as suggest guidelines to policymakers to define decarbonization targets in different scenarios. The scenario of Fayoum offers a savings of 67% in primary energy, but the associated payback period extends to 23 years due to the lower cost of energy in comparison to Naples.


2017 ◽  
Vol 26 (3) ◽  
pp. 31-41
Author(s):  
Marta Skiba ◽  
Natalia Rzeszowska

Abstract One of the five far-reaching goals of the European Union is climate change and sustainable energy use. The first step in the implementation of this task is to reduce energy demand in buildings to a minimum by 2021, and in the case of public buildings by 2019. This article analyses the possibility of improving energy efficiency in public buildings, the relationship between particular indicators of the demand for usable energy (UE), final energy (FE) and primary energy (PE) in buildings and the impact of these indicators on the assessment of energy efficiency in public buildings, based on 5 variants of extensive thermal renovation of a school building. The analysis of the abovementioned variants confirms that the thermal renovation of merely the outer envelope of the building is insufficient and requires the use of additional energy sources, for example RES. Moreover, each indicator of energy demand in the building plays a key role in assessing the energy efficiency of the building. For this reason it is important to analyze each of them individually, as well as the dependencies between them.


2020 ◽  
pp. 169-177
Author(s):  
V.S. Piven

The research reveals the theoretical and practical aspects of the green energy sector. The article compares the level of development of the green energy sector in the European Union and Ukraine. Different indicators, including the share of energy from renewable sources in Ukraine, the interaction between the level of GDP per capita and the share of renewable energy in the EU and Ukraine, and the structure of the renewable energy resources of Ukraine and the EU are taken into account. The article discussed the role of financial and non-financial tools for the development of the green energy sector in the EU countries. The research states that the countries can be divided into three groups, where group A involves countries with a highly developed green energy sector, group B – member-states with progress in the transition to alternative sources of energy, and group C – countries with weak or no progress in the development of renewable energy sector. The research explains the impact of economic prosperity in developed countries on the renewable energy sector. It investigates that there is a very small positive correlation between the independent variable and the dependent variable. In general, it demonstrates that there is no correlation between the economic condition of very developed countries and the level of their green energy efficiency. The article suggests policy-making changes for the stable development of green energy in both the EU and Ukraine. Revision of existing government's medium and long term plans and adapting them to current circumstances, the gradual reduction of subsidies and reform of energy pricing, the regulatory focus on energy efficiency, the attraction of private investments through the use of domestic and donor investments are determined as important actions for stable development of green energy sector.


2015 ◽  
Vol 10 (1) ◽  
pp. 12-33 ◽  
Author(s):  
Robert Staiger ◽  
Adrian Tanţău

Abstract Heating application efficiency is a crucial point for saving energy and reducing greenhouse gas emissions. Today, EU legal framework conditions clearly define how heating systems should perform, how buildings should be designed in an energy efficient manner and how renewable energy sources should be used. Using heat pumps (HP) as an alternative “Renewable Energy System” could be one solution for increasing efficiency, using less energy, reducing the energy dependency and reducing greenhouse gas emissions. This scientific article will take a closer look at the different efficiency dependencies of such geothermal HP (GHP) systems for domestic buildings (small/medium HP). Manufacturers of HP appliances must document the efficiency, so called COP (Coefficient of Performance) in the EU under certain standards. In technical datasheets of HP appliances, these COP parameters give a clear indication of the performance quality of a HP device. HP efficiency (COP) and the efficiency of a working HP system can vary significantly. For this reason, an annual efficiency statistic named “Seasonal Performance Factor” (SPF) has been defined to get an overall efficiency for comparing HP Systems. With this indicator, conclusions can be made from an installation, economy, environmental, performance and a risk point of view. A technical and economic HP model shows the dependence of energy efficiency problems in HP systems. To reduce the complexity of the HP model, only the important factors for efficiency dependencies are used. Dynamic and static situations with HP´s and their efficiency are considered. With the latest data from field tests of HP Systems and the practical experience over the last 10 years, this information will be compared with one of the latest simulation programs with the help of two practical geothermal HP system calculations. With the result of the gathered empirical data, it allows for a better estimate of the HP system efficiency, their economic costs and benefits and their environmental impact.


2021 ◽  
Vol 13 (13) ◽  
pp. 7251
Author(s):  
Mushk Bughio ◽  
Muhammad Shoaib Khan ◽  
Waqas Ahmed Mahar ◽  
Thorsten Schuetze

Electric appliances for cooling and lighting are responsible for most of the increase in electricity consumption in Karachi, Pakistan. This study aims to investigate the impact of passive energy efficiency measures (PEEMs) on the potential reduction of indoor temperature and cooling energy demand of an architectural campus building (ACB) in Karachi, Pakistan. PEEMs focus on the building envelope’s design and construction, which is a key factor of influence on a building’s cooling energy demand. The existing architectural campus building was modeled using the building information modeling (BIM) software Autodesk Revit. Data related to the electricity consumption for cooling, building masses, occupancy conditions, utility bills, energy use intensity, as well as space types, were collected and analyzed to develop a virtual ACB model. The utility bill data were used to calibrate the DesignBuilder and EnergyPlus base case models of the existing ACB. The cooling energy demand was compared with different alternative building envelope compositions applied as PEEMs in the renovation of the existing exemplary ACB. Finally, cooling energy demand reduction potentials and the related potential electricity demand savings were determined. The quantification of the cooling energy demand facilitates the definition of the building’s electricity consumption benchmarks for cooling with specific technologies.


Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2538
Author(s):  
Praveen K. Cheekatamarla

Electrical and thermal loads of residential buildings present a unique opportunity for onsite power generation, and concomitant thermal energy generation, storage, and utilization, to decrease primary energy consumption and carbon dioxide intensity. This approach also improves resiliency and ability to address peak load burden effectively. Demand response programs and grid-interactive buildings are also essential to meet the energy needs of the 21st century while addressing climate impact. Given the significance of the scale of building energy consumption, this study investigates how cogeneration systems influence the primary energy consumption and carbon footprint in residential buildings. The impact of onsite power generation capacity, its electrical and thermal efficiency, and its cost, on total primary energy consumption, equivalent carbon dioxide emissions, operating expenditure, and, most importantly, thermal and electrical energy balance, is presented. The conditions at which a cogeneration approach loses its advantage as an energy efficient residential resource are identified as a function of electrical grid’s carbon footprint and primary energy efficiency. Compared to a heat pump heating system with a coefficient of performance (COP) of three, a 0.5 kW cogeneration system with 40% electrical efficiency is shown to lose its environmental benefit if the electrical grid’s carbon dioxide intensity falls below 0.4 kg CO2 per kWh electricity.


Sign in / Sign up

Export Citation Format

Share Document