Optimization of the HVAC system design to minimize primary energy demand

Purpose The purpose of this paper is to present a method for the environmental impact analysis of machine-tool cutting, which enables the detailed analysis of inventory data on resource consumption and waste emissions, as well as the quantitative evaluation of environmental impact. Design/methodology/approach The proposed environmental impact analysis method is based on the life cycle assessment (LCA) methodology. In this method, the system boundary of the cutting unit is first defined, and inventory data on energy and material consumptions are analyzed. Subsequently, through classification, five important environmental impact categories are proposed, namely, primary energy demand, global warming potential, acidification potential, eutrophication potential and photochemical ozone creation potential. Finally, the environmental impact results are obtained through characterization and normalization. Findings This method is applied on a case study involving a machine-tool turning unit. Results show that primary energy demand and global warming potential exert the serious environmental impact in the turning unit. Suggestions for improving the environmental performance of the machine-tool turning are proposed. Originality/value The environmental impact analysis method is applicable to different machine tools and cutting-unit processes. Moreover, it can guide and support the development of green manufacturing by machinery manufacturers.

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Optimization of the energy supply in the plastics industry to reduce the primary energy demand

Journal of Cleaner Production ◽

10.1016/j.jclepro.2018.04.254 ◽

2018 ◽

Vol 192 ◽

pp. 790-800 ◽

Cited By ~ 7

Author(s):

Heiko Dunkelberg ◽

Johannes Wagner ◽

Conrad Hannen ◽

B. Alexander Schlüter ◽

Long Phan ◽

...

Keyword(s):

Energy Supply ◽

Energy Demand ◽

Primary Energy ◽

Primary Energy Demand ◽

Plastics Industry

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Myth v. Fact

Mechanical Engineering ◽

10.1115/1.2011-jan-1 ◽

2011 ◽

Vol 133 (01) ◽

pp. 24-29 ◽

Cited By ~ 2

Author(s):

John Reilly ◽

Allison Crimmins

Keyword(s):

Energy Demand ◽

Alternative Energy ◽

Nuclear Energy ◽

Fossil Fuels ◽

Fossil Fuel ◽

Primary Energy ◽

Electricity Production ◽

Energy Prices ◽

Primary Energy Demand ◽

Business As Usual

This article predicts future global energy demand under a business-as-usual scenario. According to the MIT projections, conventional technology supported by fossil fuels will continue to dominate under a business-as-usual scenario. In fact, in the absence of climate policies that would impact energy prices, fossil fuels will supply nearly 80% of global primary energy demand in 2100. Alternative energy technologies will expand rapidly. Non-fossil fuel use will grow from 13% to 20% by 2100, with renewable electricity production expanding nearly tenfold and nuclear energy increasing by a factor of 8.5. However, those sources currently provide such a small share of the world's energy that even rapid growth is not enough to significantly displace fossil fuels. In spite of the growth in renewables, the projections indicate that coal will remain among the least expensive fuel sources. Non-fossil fuel alternatives, such as renewable energy and nuclear energy, will be between 40% and 80% more expensive than coal.

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The possibility of achievement of the nZEB state of a refurbished detached house powered solely by renewable energy sources in Southern Poland

E3S Web of Conferences ◽

10.1051/e3sconf/20187001001 ◽

2018 ◽

Vol 70 ◽

pp. 01001

Author(s):

Jacek Biskupski

Keyword(s):

Renewable Energy ◽

Energy Demand ◽

Renewable Energy Sources ◽

Primary Energy ◽

Heat Pumps ◽

Space Heating ◽

Zero Energy ◽

Electricity Grid ◽

Primary Energy Demand ◽

Pv Generator

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.

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Energy Embedded in Food Loss Management and in the Production of Uneaten Food: Seeking a Sustainable Pathway

Energies ◽

10.3390/en12040767 ◽

2019 ◽

Vol 12 (4) ◽

pp. 767 ◽

Cited By ~ 11

Author(s):

Daniel Hoehn ◽

María Margallo ◽

Jara Laso ◽

Isabel García-Herrero ◽

Alba Bala ◽

...

Keyword(s):

Supply Chain ◽

Energy Loss ◽

Food Supply ◽

Energy Demand ◽

Energy Recovery ◽

Primary Energy ◽

Food Supply Chain ◽

Food Loss ◽

Food Energy ◽

Primary Energy Demand

Recently, important efforts have been made to define food loss management strategies. Most strategies have mainly been focused on mass and energy recovery through mixed food loss in centralised recovery models. This work aims to highlight the need to address a decentralised food loss management, in order to manage the different fractions and on each of the different stages of the food supply chain. For this purpose, an energy flow analysis is made, through the calculation of the primary energy demand of four stages and 11 food categories of the Spanish food supply chain in 2015. The energy efficiency assessment is conducted under a resource use perspective, using the energy return on investment (EROI) ratio, and a circular economy perspective, developing an Energy return on investment – Circular economy index (EROIce), based on a food waste-to-energy-to-food approach. Results suggest that the embodied energy loss consist of 17% of the total primary energy demand, and related to the food categories, the vegetarian diet appears to be the most efficient, followed by the pescetarian diet. Comparing food energy loss values with the estimated energy provided for one consumer, it is highlighted the fact that the food energy loss generated by two to three persons amounts to one person's total daily intake. Moreover, cereals is the category responsible for the highest percentage on the total food energy loss (44%); following by meat, fish and seafood and vegetables. When the results of food energy loss and embodied energy loss are related, it is observed that categories such as meat and fish and seafood have a very high primary energy demand to produce less food, besides that the parts of the food supply chain with more energy recovery potential are the beginning and the end. Finally, the EROIce analysis shows that in the categories of meat, fish and seafood and cereals, anaerobic digestion and composting is the best option for energy recovery. From the results, it is discussed the possibility to developed local digesters at the beginning and end of the food supply chain, as well as to developed double digesters installations for hydrogen recovery from cereals loss, and methane recovery from mixed food loss.

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