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Operational energy use in buildings accounts for 28% of global energy demand. One method to reduce operational energy is upgrading old appliances to more efficient ones. In Australia, the most common residential heating type is reverse-cycle heating, followed by gas heating. This article aims to determine the energy balance resulting from a gas heating upgrade through a life cycle assessment (LCA).

Extensive primary data were collected for operational energy performance of 61 ducted gas heating upgrades. To address the scarcity of data on material composition, one ducted gas heater was deconstructed and assessed in terms of material composition (types and weights). The comparison between embodied energy and operational energy savings allows us to establish whether operational energy savings offset the embodied energy incurred with the upgrade. The end of life stage of the old appliance, as well as the production, construction and use stage of the new appliance were assessed.

The results show that the operational energy savings offset the following impact categories: global warming, ozone layer depletion, aquatic acidification, nonrenewable energy and carcinogens. Only the mineral extraction is not offset by the operational energy savings. The results clearly demonstrate that operational energy savings outweigh the embodied energy and therefore contribute positively to the environment.

This study is the first to focus on the LCA of building services through extensive primary data collection and a focus on a high number of appliances. This supports ongoing energy efficient upgrades in Australia and paves the way for further, similar studies to confirm or disprove these findings in other parts of the world.

The purpose of this paper is to evaluate the energy, economic and environmental performance of commercial water heating systems in Hong Kong special administrative region (SAR), China.

The research team contacted 50 facilities managers in Hong Kong, and 16 of them agreed to participate in this territorial-wide survey. The overall efficiency of different water heating systems was determined through measurements of inlet water temperatures, outlet steam/water properties, the amount of steam/water produced and the amount of energy consumed. The cost effectiveness and the amount of greenhouse gases produced per megajoule (MJ) output were also determined.

Results show that electric water heating systems had the highest mean overall efficiency, followed by gas- and oil-fired systems. However, the difference between the mean overall efficiency of the three types of water heating systems was not statistically significant, as the systems had been inspected and maintained regularly. Oil-fired systems were found to be the most cost-effective when taking fuel prices into consideration. Environmental analysis showed that gas-fired systems produced the least amount of greenhouse gases per MJ output.

Water heating is one of the major uses of energy in buildings. Hence, the efficiency of a water heating system can have a significant effect on the overall performance of a building. This paper not only provides insight on the energy performance but it also evaluates the economic and environmental performance of water heating systems.

The gas assisted Iaser heating of engineering surfaces finds wide application in industry. Numerical simulation of the heating process may considerably reduce the cost spent on experimentation. In the present study, 2‐dimensional axisymmetric flow and energy equations are solved numerically using a control volume approach for the case of a gas assisted laser heating of steel surfaces. Various turbulence models including standard k‐ε, k‐ε YAP, low Reynolds number k‐ε and RSTM models are tested. The low Reynolds number k‐ε model is selected to account for the turbulence. Variable properties of both solid and gas are taken into account during the simulation. Air is considered as an assisting gas impinging the workpiece surface coaxially with the laser beam. In order to validate the presently considered methodology, the study is extended to include comparison of present predictions with analytical solution for the case available in the literature. It is found that the assisting gas jet has some influence on the temperature profiles. This effect is minimum at the irradiated spot center and it amplifies considerably in the gas side. In addition, account for the variable properties results in lower surface temperatures as compared to the constant properties case.

Promoting clean heating in rural areas is crucial for achieving a low-carbon transition of energy consumption and China's dual-carbon target. The study aims to consider the energy stacking behavior in heating energy use, reveals the determinants that affect household cleaner heating choices under the winter clean heating plan (WCHP), and proposes policy recommendations for the sustainable promotion of clean heating.

With unique rural household survey data covering the clean heating pilot regions in northern China in 2020, this study estimates the relationship between driving factors and heating energy choices through binary and multivariate probit models.

The regression estimates show that the main drivers of heating energy choices include household income per capita, education level of household head, knowledge of the WCHP, access to heating subsidies and perception of indoor air pollution. There is energy stacking behavior in rural household heating energy use. Household decisions to adopt electricity or clean coal heating are correlated with firewood or soft coal use.

This study is one of the few to investigate the heating energy use of rural households by allowing for the adoption of multiple energy types. Combined with a unique microsurvey dataset, it could provide rich information for formulating proper energy transition planning. The findings also shed light on the importance of heating subsidies, households' knowledge of WCHP and awareness of environmental health in choosing clean heating energy, which has not been fully valued in related research.

The purpose of this paper is to present a methodology for estimating scheduled and manual override heating events and heating settings from indoor air temperature and gas use measurements in UK homes.

Living room air temperature and gas use data were measured in ten UK homes built to low energy standards. The temperature measurements are used to establish whether the central heating system is turned on or off and to estimate the heating setpoint used. The estimated heating periods are verified using the homes' average daily gas consumption profiles.

Using this method, the average number of heating periods per day was 2.2 (SD = 0.8) on weekdays and 2.7 (SD = 0.5) on weekends. The weekday mean heating duration was 8.8 h and for weekends, it was 9.8 h. Manual overrides of the settings occurred in all the dwellings and added an average of 2.4 h and 1.5 h to the heating duration on weekdays and weekends respectively. The mean estimated setpoint temperatures were 21.2 and 21.4°C on weekdays and weekends respectively.

Manual overrides of heating behaviours have only previously been assessed by questionnaire survey. This paper demonstrates an alternative method to identifying these manual override events and responds to a key gap in the current body of research that little is currently reported on the frequency and duration of manual heating overrides in UK homes.

The results could be used to better inform the assumptions of space heating behaviour used in energy models in order to more accurately predict the space heating energy demands of dwellings.

Manual overrides of heating behaviours have only previously been assessed by questionnaire survey. This paper demonstrates an alternative method to identifying these manual override events and responds to a key gap in the current body of research that little is currently reported on the frequency and duration of manual heating overrides in UK homes.

The purpose of this paper is to investigate the effect of different heating approaches during thermal rounding of polymer powders on powder bulk properties such as particle size, shape and flowability, as well as on the yield of process.

This study focuses on the rounding of commercial high-density polyethylene polymer particles in two different downer reactor designs using heated walls (indirect heating) and preheated carrier gas (direct heating). Powder bulk properties of the product obtained from both designs are characterized and compared.

Particle rounding with direct heating leads to a considerable increase in process yield and a reduction in powder agglomeration compared to the design with indirect heating. This subsequently leads to higher powder flowability. In terms of shape, indirect heating yields not only particles with higher sphericity but also entails substantial agglomeration of the rounded particles.

Shape modification via thermal rounding is the decisive step for the success of a top-down process chain for selective laser sintering powders with excellent flowability, starting with polymer particles from comminution. This report provides new information on the influence of the heating mode (direct/indirect) on the performance of the rounding process and particle properties.

Looks at models constructed for the gas industry domestic, central heating, cooling and industrial markets. Shows how these models can be used to permit the rapid assessment of marketing targets for appliance sales and price levels against gas supply constraints. Concludes that although these models do not provide instant solutions to the marketing problems of the gas industry they do help to organize available data in a more efficient way.

This paper aims to investigate the relationship between domestic natural gas consumption and climate change in the Greater Dublin Region.

Based on historical climate and natural gas use data, a linear regression model was derived to estimate the impact of future climate change on natural gas consumption under different climate scenarios.

Generally, under controlled socioeconomic development, the climate scenarios by Hadley model and the Ensemble GCMs are likely to decrease future natural gas consumption per capita and related CO₂ emissions compared to present. These results indicate that climate change has become as one of the most important factors affecting the energy system.

This study contributes understanding of the long‐term impact of climate change on regional domestic natural gas use. It provides the national and local authorities a methodology to anticipate the potential impacts on domestic energy use and enable urban areas to maximise any benefits and minimise any losses from climate change.

To highlight the effect of viscous and Joule heating on different ionized gases in the presence of magneto and thermal radiation effects.

The conservation equations are written for the MHD forced convection in the presence of thermal radiation. The governing equations are transformed into non‐similar form using a set of dimensionless variables and then solved numerically using Keller box method.

The increasing of fluid suction parameter enhances local Nusselt numbers, while the increasing of injection parameter decreases local Nusselt numbers. The inclusion of thermal radiation increases the heat transfer rate for both ionized gases suction or injection. The presence of magnetic field decreases the heat transfer rate for the suction case and increases it for the injection case. Finally, the heat transfer rate is decreased due to viscous dissipation.

The combined effects of both viscous and Joule heating on the forced convection heat transfer of ionized gases for constant surface heat flux surfaces can be investigated.

A very useful source of coefficient of heat transfer values for engineers planning to transfer heat by using ionized gases.

The viscous and Joule heating of ionized gases on forced convection heat transfer in the presence of magneto and thermal radiation effects are investigated and can be used by different engineers working on industry.

The purpose of this paper is to shed fresh light into whether an energy commodity price index (ENFX) and energy blockchain-based crypto price index (ENCX) can be used to predict movements in the energy commodity and energy crypto market.

Using principal component analysis over daily data of crude oil, heating oil, natural gas and energy based cryptos, the ENFX and ENCX indices are constructed, where ENFX (ENCX) represents 94% (88%) of variability in energy commodity (energy crypto) prices.

Natural gas price movements were better explained by ENCX, and shared positive (negative) correlations with cryptos (crude oil and heating oil). Using a vector autoregressive model (VAR), while the 1-day lagged ENCX (ENFX) was significant in estimating current ENCX (ENFX) values, only lagged ENCX was significant in estimating current ENFX. Granger causality tests confirmed the two markets do not granger cause each other. One standard deviation shock in ENFX had a negative effect on ENCX. Weak forecasting results of the VAR model, support the two markets are not robust forecasters of each other. Robustness wise, the VAR model ranked lower than an autoregressive model, but higher than a random walk model.

Significant structural breaks at distinct dates in the two markets reinforce that the two markets do not help to predict each other. The findings are limited by the existence of bubbles (December 2017-January 2018) which were witnessed in energy blockchain-based crypto markets and natural gas, but not in crude oil and heating oil.

As per the authors’ knowledge, this is the first paper to analyze the relationship between leading energy commodities and energy blockchain-based crypto markets.