Primary Energy Usage Research Articles

Techno-Economic Analysis of Solar Absorption Cooling for Commercial Buildings in India

Space cooling and heating always tends to be a major part of the primary energy usage. By using fossil fuel electricity for these purposes, the situation becomes even worse. One of the major electricity consumptions in India is air conditioning. There are a lot of different technologies and few researchers have come up with a debate between solar absorption cooling and PV electric cooling. In a previous paper, PV electric cooling was studied and now as a continuation, this paper focuses on solar thermal absorption cooling systems and their application in commercial/office buildings in India. A typical Indian commercial building is taken for the simulation in TRNSYS. Through this simulation, the feasibility and operational strategy of the system is analysed, after which parametric study and economic analysis of the system is done. When compared with the expenses for a traditional air conditioner unit, this solar absorption cooling will take 13.6 years to pay back and will take 15.5 years to payback the price of itself and there after all the extra money are savings or profit. Although the place chosen for this study is one of the typical tropical place in India, this payback might vary with different places, climate and the cooling demand.Article History: Received May 12th 2017; Received in revised form August 15th 2017; Accepted 1st Sept 2017; Available onlineHow to Cite This Article: Narayanan, M. (2017). Techno-Economic Analysis of Solar Absorption Cooling for Commercial Buildings in India. International Journal of Renewable Energy Development, 6(3), 253-262.https://doi.org/10.14710/ijred.6.3.253-262

Techno-Economic Analysis of Solar Absorption Cooling for Commercial buildings in India

Space cooling and heating always tends to be a major part of the primary energy usage. By using fossil fuel electricity for these purposes, the situation becomes even worse. One of the major electricity consumptions in India is air conditioning. There are a lot of different technologies and few researchers have come up with a debate between solar absorption cooling and PV electric cooling. In a previous paper, PV electric cooling was studied and now as a continuation, this paper focuses on solar thermal absorption cooling systems and their application in commercial/office buildings in India. A typical Indian commercial building is taken for the simulation in TRNSYS. Through this simulation, the feasibility and operational strategy of the system is analysed, after which parametric study and economic analysis of the system is done. When compared with the expenses for a traditional air conditioner unit, this solar absorption cooling will take 13.6 years to pay back and will take 15.5 years to payback the price of itself and there after all the extra money are savings or profit. Although the place chosen for this study is one of the typical tropical place in India, this payback might vary with different places, climate and the cooling demand.Article History: Received May 12th 2017; Received in revised form August 15th 2017; Accepted 1st Sept 2017; Available onlineHow to Cite This Article: Narayanan, M. (2017). Techno-Economic Analysis of Solar Absorption Cooling for Commercial Buildings in India. International Journal of Renewable Energy Development, 6(3), 253-262.https://doi.org/10.14710/ijred.6.3.253-262

Energy savings potential from improved building controls for the US commercial building sector

The US Department of Energy (DOE) sponsored a study to determine the national savings achievable in the commercial buildings through widespread deployment of controls, elimination of faults, and use of better sensing. The study estimated savings from 34 measures in 9 building types and across 16 climates. These buildings are responsible for almost 57% of the US commercial building sector energy consumption. In addition to the individual measures, three packages of measures were created to estimate savings: (1) efficient building, (2) typical building, and (3) inefficient building. The results showed significant potential for energy savings across all building types and climates. The total site potential savings by building type aggregated across all climates for each measure varied between 0 and 16%. The total site potential savings aggregated across all building types and climates for each measure varied between 0 and 11%. The national potential site energy savings across all building types studied is 29%. Across all building types, the savings represent approximately 1393 PJ (1.32 quads) of site energy savings or 2912 PJ (2.76 quads) of primary (or source) energy savings. Extrapolating the results for other building types not analyzed as part of this study, the primary energy savings could be in the range of 4220 to 5275 PJ. For comparison, the total US primary energy consumption across all sectors of energy use was 102,762 PJ (97.4 quads) in 2015. This makes commercial building control improvements strategically important to sustained reductions in national energy consumption. To realize most of this potential savings, many gaps can be addressed through research development and deployment (RD&D), as recommended in this paper.

Open-source energy planning tool with easy-to-parameterize components for the conception of polygeneration systems

Polygeneration systems are a key technology for the reduction of primary energy usage and emissions. High costs, lack of flexibility and effort for parameterization hinder the wide usage of modeling tools during their conceptual design. This paper describes how planning tools can be structured for the conceptual design phase where only little information is available to the planner. A library concept was developed using the principles of object-oriented modeling to address the flexibility issue. With respect to cost and expandability, the open-source modeling language Modelica was chosen. Furthermore, easy-to-parameterize component models were developed. In addition to the improved library concept and novel component models, an easy-to-adapt control concept is proposed. The component models were validated and the applicability of the library was demonstrated by means of an example. It was shown that the data usually obtained from spec sheets are sufficient to parameterize the models. In addition to this, the control concept was approved.

Energy and environmental evaluation of combined cooling heating and power system

The paper addresses issues involving problems of implementing combined cooling, heating and power (CCHP) system to industrial facility with well-defined demand profiles of cooling, heating and electricity. The application of CCHP system in this particular industrial facility is being evaluated by comparison with the reference system that consists of three conventional methods of energy supply: (a) electricity from external grid, (b) heat from gas-fired boilers and (c) cooling from vapour compression chillers run by electricity from the grid. The CCHP system scenario is based on the combined heat and power (CHP) plant with gas turbine-compressor arrangement and water/lithium bromide absorption chiller of a single-effect type. Those two scenarios are analysed in terms of annual primary energy usage as well as emissions of CO 2 . The results of the analysis show an extent of primary energy savings of the CCHP system in comparison with the reference system. Furthermore, the environmental impact of the CCHP usage, in the form of greenhouse gases emission reductions, compares quite favourably with the reference conventional option.

Analysis of energy development sustainability: The example of the lithuanian district heating sector

Today, sustainable energy development is one of key issues on European development agenda. The article describes one of sustainable energy development promoting tool - the eco-labelling scheme for district heating and cooling systems elaborated within the framework of Intelligent Energy for Europe program project “Ecoheat4cities” and partially funded by European Agency for Competitiveness and Innovation. The scheme is based on measured energy and environmental performance data of the district heating and cooling system and considers primary non-renewable energy usage together with the share of renewable energy and carbon dioxide emissions calculated using life-cycle analysis methodology. The “power bonus” approach is used for performance indicators of the heat generated in cogeneration installations. An analysis of a number of Lithuanian district heating companies using elaborated labelling criteria shows positive trends towards fulfilling Lithuania's energy policy goals. The labelling scheme gives opportunity for policy makers and urban planners to compare different heat supply options and decide upon exploiting district heating advantages and benefits for reaching EU energy and environment policy goals.

System Dynamics Framework to Study the Effect of Material Performance on a Building’s Lifecycle Energy Requirements

AbstractThe buildings sector accounts for nearly 41% of the United States’ primary energy usage. Various lifecycle analysis (LCA)-based tools are available for facilitating sustainable material selection and energy usage estimation, especially during the material production and construction phases of a building. However, for the use and maintenance phase, there is a lack of a comprehensive framework that can monitor and quantify the effects of various factors such as building system and material deterioration and dynamic occupant behavior patterns on the energy consumption. This research propose a lifecycle energy monitoring framework that couples LCA and energy simulation analysis using a system dynamics modeling framework to enable a distributed simulation platform that can monitor and control the energy requirements during all phases of a building’s lifecycle. Experimental results indicate that the proposed framework can help understand the optimal maintenance and replacement period of major building m...

Heat recovery investigation from dryer–thermal oxidizer system in corn-ethanol plants

In recent years, annual corn ethanol production in the U.S. has exceeded 13,298,000,000 gallons. However, net energy balance for this sector became a subject of controversy in many discussions.The aim of the presented research is an investigation of thermal improvement opportunities in a corn ethanol plant. For this purpose, a complex mathematical model was developed for a dryer–thermal oxidizer system. Three variants were subjected thermodynamic analyses: one state of the art system and two proposed system modifications. The properties of humid gas, a mixture of combustion products and moisture evaporated from distiller's grain, were updated based on the steam properties according to the formulation proposed by the International Association for the Properties of Water and Steam. All calculations were performed by uniquely-developed C++ code.The results indicate major potential for improvement in the following areas: (i) water recovery from humid gas; (ii) heat recovery from moisture condensation – max. 44% of total primary energy usage (TPEU); and (iii) fuel savings by reduction of humid gas flow through a thermal oxidizer – max. 1.4% of TPEU. Also the presented analysis can be a starting point for further modifications in real corn ethanol manufacturing applications, leading towards pilot system implementation.

A Carbon Footprint of Textile Recycling: A Case Study in Sweden

SummaryGlobal population growth and rising living standards are increasing apparel consumption. Consequently, consumption of resources and generation of textile waste are increasing. According to the Swedish Environmental Protection Agency, textile consumption increased by 40% between the years 2000 and 2009 in Sweden. Given that there is currently no textile recycling plant in Sweden, the aim of this article is to explore the potential environmental benefits of various textile recycling techniques and thereby direct textile waste management strategies toward more sustainable options. Three different recycling techniques for a model waste consisting of 50% cotton and 50% polyester were identified and a life cycle assessment (LCA) was made to assess the environmental performance of them. The recycling processes are: material reuse of textile waste of adequate quality; separation of cellulose from polyester using N‐methylmorpholine‐N‐oxide as a solvent; and chemical recycling of polyester. These are compared to incineration, representing conventional textile waste treatment in Sweden. The results show that incineration has the highest global warming potential and primary energy usage. The material reuse process exhibits the best performance of the studied systems, with savings of 8 tonnes of carbon dioxide equivalents (CO2‐eq) and 164 gigajoules (GJ) of primary energy per tonne of textile waste. Sensitivity analyses showed that results are particularly sensitive to the considered yields of the processes and to the choice of replaced products. An integration of these recycling technologies for optimal usage of their different features for treatment of 1 tonne of textile waste shows that 10 tonnes CO2‐eq and 169 GJ of primary energy could be saved.

Modelling the Evolutionary Paths of Multiple Carbon-Free Energy Technologies with Policy Incentives

In this paper, we establish an economy-energy-environment integrated model by introducing a new technical mechanism, that is, the revised logistic model, to be the technical core of the energy module. This gives the conventional top-down modes more bottom-up features and allows us to model the evolutionary pathways of multiple non-carbon technologies. The model’s simulations indicate that the mixed policy of both carbon tax and subsidy plays a significant part in promoting the development of new energy technologies. The shares in total primary energy usage for PV solar, geothermal power and wind energy, for example, will have increased to 24.9, 9.7 and 6.12 %, respectively. Meanwhile, technological progress can be significantly enhanced by introducing research and development (R&D) investment. As a result, the percentages of usage of the above three technologies are likely to increase to 26.2, 12.1 and 7.2 %, respectively, in that case. Besides, energy supply market will be locked up by non-fossil energy as early as 2035, or thereabouts, under the current R&D investment regime. Thus, the expansion of R&D may significantly improve the carbon-reducing potential of the mixed policy and perform well in easing the tax burden on businesses and consumers in the long run.

Simulation of hybrid renewable microgeneration systems for variable electricity prices

This paper addresses a hybrid renewable system that consists of a micro-Combined Cooling Heat and Power (CCHP) unit and a solar energy conversion device. In addition to a traditional PV system, a High Concentrator Photovoltaic (HCPV) device, the design of which is suitable for building integration application, was also modelled and embedded in the hybrid system. The work identifies the optimal management strategies for the hybrid renewable system in an effort to minimise the primary energy usage, the carbon dioxide emissions and the operational costs for variable electricity prices that result from the day-ahead electricity market. An “ad hoc” model describes the performance of the HCPV module, PV and Internal Combustion Engine, whilst the other units were simulated based on their main characteristic parameters. The developed algorithm was applied to three different building typologies. The results indicate that the best configuration is the hybrid renewable system with PV, which can provide a yearly primary energy reduction of between 20% and 30% compared to separate production. The hybrid renewable system with HCPV becomes competitive with the PV technology when the level of solar radiation is high.

Modelling and selection of micro-CHP systems for domestic energy supply: The dimension of network-wide primary energy consumption

Mathematical modelling and optimisation of the Distributed Energy Supply System (DESS) using natural gas, both at the building level and the overall energy supply network level was carried out for three types of micro-combined heat and power (micro-CHP) – solid oxide fuel cells, Stirling engines, internal combustion engines – and for two different operating strategies – cost-driven and primary energy-driven. The modelling framework captures the overall impact of the adoption of micro-CHP systems on the total primary energy usage in both generation and distribution. A detailed case study on the UK domestic energy supply was undertaken by applying both operating strategies to four different sizes of houses. The best technology selected in each case was evaluated in terms of the economics, total primary energy consumption, and reduction of central power generation requirement. It was shown that the primary energy consumption driven option selected technologies which could potentially achieve 6–10% reduction of total primary energy use compared to the base case where micro-CHP was not adopted, which is nearly two times the reduction by the cost-driven strategy.

Grand Challenges in Bioenergy and Biofuel Research: Engineering and Technology Development, Environmental Impact, and Sustainability

SPECIALTY GRAND CHALLENGE article Front. Energy Res., 30 September 2013 | https://doi.org/10.3389/fenrg.2013.00004

Projecting Long-Term Primary Energy Consumption

In this paper we use the long-term empirical relationship among primary energy consumption, real income, physical capital, population and technology, obtained by averaged panel error correction models, to project the long-term primary energy consumption of 56 countries up to 2100. In forecasting long-term primary energy consumption, we work with four different Shared Socioeconomic Pathway Scenarios (SSPs) developed for the Intergovernmental Panel on Climate Change (IPCC) framework, assuming different challenges to adaptation and mitigation. We find that in all scenarios, China, the United States and India will be the largest energy consumers, while highly growing countries will also significantly contribute to energy use. We observe for most scenarios a sharp increase in global energy consumption, followed by a levelling-out and a decrease towards the second half of the century. The reasons behind this pattern are not only slower population growth, but also infrastructure saturation and increased total factor productivity. This means, as countries move towards more knowledge based societies, and higher energy efficiency, their primary energy usage is likely to decrease as a result. Global primary energy consumption is expected however to increase significantly in the coming decades, thus increasing the pressure on policy makers to cope with the questions of energy security and greenhouse gas mitigation at the same time.

Waste Heat Recovery in Data Centers Using Sorption Systems

Of the total electricity consumption by the United States in 2006, more than 1% was used on data centers alone; a value that continues to rise rapidly. Of the total amount of electricity a data center consumes, about 30% is used to cool server equipment. The present study conceptualizes and analyzes a novel paradigm consisting of integrated power, cooling, and waste heat recovery and upgrade systems that considerably lower the energy footprint of data centers. Thus, on-site power generation equipment is used to supply primary electricity needs of the data center. The microturbine-derived waste heat is recovered to run an absorption chiller that supplies the entire cooling load of the data center, essentially providing the requisite cooling without any additional expenditure of primary energy. Furthermore, the remaining waste heat rejected by the data center is boosted to a higher temperature with a heat transformer, with the upgraded thermal stream serving as an additional output of the data center with negligible additional electrical power input. Such upgraded heat can be used for district heating applications in neighboring residential or commercial buildings, or as process heat for commercial end uses such as laundries, hospitals, and restaurants, depending on the location of the data center. With such a system, the primary energy usage of the data center as a whole can be reduced by up to 23% while still addressing the high-flux cooling loads, in addition to providing a new income stream through the sales of upgraded thermal energy. Given the large and fast-escalating energy consumption patterns of data centers, this novel, integrated approach to electricity and cooling supply, and waste heat recovery and upgrade will substantially reduce primary energy consumption for this important end use worldwide.

A review of domestic heat pumps

Heat pumps are a promising technology for heating (and cooling) domestic buildings that provide exceptionally high efficiencies compared with fossil fuel combustion. There are in the region of a billion heat pumps in use world-wide, but despite their maturity they are a relatively new technology to many regions. This article gives an overview of the state-of-the-art technologies and the practical issues faced when installing and operating them. It focuses on the performance obtained in real-world operation, surveying the published efficiency figures for hundreds of air source and ground source heat pumps (ASHP and GSHP), and presenting a method to relate these to results from recent UK and German field trials. It also covers commercial aspects of the technologies, the typical savings in primary energy usage, carbon dioxide emissions abatement that can be realised, and wider implications of their uptake.

A hybrid optimized artificial intelligent model to forecast crude oil using genetic algorithm

Crude oil is one of the most critical energy commodities while with coal and natural gas are projected to provide roughly the 86% share of the total US primary energy supply in 2030. In this study, a novel hybrid optimum model based on artificial intelligent (AI) is proposed for world crude oil spot price forecasting. A three-layer feed forward neural network (FNN) model was used to model the oil price forecasting. Genetic algorithm (GA) is employed not only to improve the learning algorithm, but also to reduce the complexity in parameter space. GA optimizes simultaneously, the connection weights between layers and the thresholds. In addition, GA reduces the dimension of the feature space and eliminates irrelevant factors. For verification and testing, two main crude oil price series, West Texas intermediate (WTI) crude oil spot price, Brent crude oil spot price and Iran crude oil are used to test the effectiveness of the proposed optimized neural network. Results show that optimized model has advantages in comparison with conventional ANN in terms of accuracy, variability, model creation and model examination. Both simulated and actual data sets are used for comparison. Key word: Artificial neural network, crude oil, genetic algorithm, optimization.

Energy harvesting, reuse and upgrade to reduce primary energy usage in the USA

Two-thirds of input energy for electricity generation in the USA is lost as heat during conversion processes. Additionally, 12.5% of primary fuel and 20.3% of electricity are employed for space heating, water heating, and refrigeration where low-grade heat could suffice. The potential for harnessing waste heat from power generation and thermal processes to perform such tasks is assessed. By matching power plant outlet streams with applications at corresponding temperature ranges, sufficient waste heat is identified to satisfy all USA space and water heating needs. Sufficient high temperature exhaust from power plants is identified to satisfy 27% of residential air conditioning with thermally activated refrigeration, or all industrial refrigeration and process heating from 100 to 150 °C. Engine coolant and exhaust is sufficient to satisfy all air conditioning and 68% of electrical demands in vehicles. Overall, this study demonstrates the potential to reduce USA primary energy demand by 12% and CO 2 emissions by 13% through waste heat recovery. A detailed analysis of thermal energy demand in pulp and paper manufacturing is conducted to demonstrate the methodology for improving the fidelity of this approach. These results can inform infrastructure and development to capture heat that would be lost today, substantially reducing USA energy intensity.

Why Technical Fixes Won’t Mitigate Climate Change

We may have already surpassed prudent limits for atmospheric greenhouse gas concentrations, and have exceeded (or are near) safe limits for a number of other Earth system processes. If fossil fuels maintain their present share, bringing the expected year 2050 world population up to US primary energy levels would involve a 6-fold rise in energy consumption, with a similar rise in CO 2 emissions. We argue that even a combination of the various conventional approaches for climate mitigation will prove to be ‘too little too late’. If use of geoengineering to delay some of the consequences of climate change is judged too risky, we conclude the only remaining approach for meeting the needs of all humans while staying within the Earth’s bio-capacity is to abandon our current growth-oriented economies. Even this strategy could face difficulties if population does not peak soon.

Potential opportunities and impacts of a hydrogen economy for the Australian minerals industry

The hydrogen economy is one of the key areas of interest for the reduction of societal greenhouse gas emissions. However, the potential for impact of hydrogen technologies in the transition to a hydrogen economy will vary across the different industrial sectors depending on the source and usage of current energy sources. This paper presents a broad examination of hydrogen economy opportunities and impacts for the minerals industry in Australia. The usage of hydrogen and fuel cell technology in the mining and metals production sub-sectors has differing potential as metallurgical and heavy-duty mobile energy consumption may not be feasibly substituted with hydrogen. This examination indicates a potential of 12–13% reduction in primary energy usage by the minerals industry, with a resulting reduction in greenhouse gas emissions of 9–12% without carbon capture and storage (CCS), or 53–60% reduction with CCS. Other impacts on the industry may include an increased demand for minerals to produce fuel cells, catalysts and infrastructure. Minimal local reserves of platinum group metals are likely to be the limiting capacity factor.