Energy-economic-environmental cycle evaluation comparing two polyethylene and polycarbonate plastic greenhouses in cucumber production (from production to packaging and distribution).

Excessive consumption and improper management of inputs would lead to environmental damages, as well as decreased economic benefits. Thus, a thorough examination of the entire production process from the viewpoint of energy flow, economic profit, and environmental effects can identify hotspots and facilitate input management. Accordingly, in the current investigation, energy, economic and environmental aspects of greenhouse cucumber production systems were measured by life cycle assessment (LCA) technique and cumulative exergy demand (CExD) analysis by considering different greenhouse structures. Furthermore, the data envelopment analysis (DEA) approach was used to determine the efficiency of manufacturing units and optimal consumption pattern. The information required was acquired through interviews and questionnaires with 35 greenhouse owners, and consultation with greenhouse enterprises in the Khuzestan province of Iran. Based on the findings, energy consumed was 6626.45 MJton-1 in Sc1, and 6410.32 MJton-1 in Sc 3. The findings of benchmarking revealed that boosting the efficiency of the crop production process can lower input energy by 14.80%. The energy consumption for the construction of the first and second type of greenhouses was calculated to be 14,811.13 and 17,541.73 MJ (1000 m2)-1, respectively. With regard to the production variable costs, chemical fertilizers and labor had the largest contributions to the total expenses, at 7.6 (15.41%) and 7.87 $tonne-1(15.94%), respectively. In the evaluation of the energy and economic indicators, the combined indicator of Energy Intensiveness for the first and second types of greenhouse systems was found to be 80.26 and 77.07 MJ$-1, respectively, indicating higher energy-economic productivity of the first type of system. Based on LCA results, direct emissions due to input consumption (air: carbon dioxide (CO2), and nitrogen oxides (NOx); soil: mercury (Hg), copper (Cu), and lead (Pb)), and indirect emissions induced by chemical fertilizers, greenhouse structures, and chemical pesticides production are the environmental hotspots.

Circular Economy across Australia: Taking Stock of Progress and Lessons.

Australia has intensified its circular economy (CE) efforts that demonstrate designing out waste while creating wealth. It has developed eco-industrial parks in metallurgy/metal industries, eco-cities and small-scale waste-to-wealth creation strategies. Mining has taken the lead in CE development with the eco-industrial areas at Kwinana, Western Australia, and Gladstone, Queensland. Easing up the waste burden, eco-efficiency and value addition are the direct benefits of circularizing the economy. Shortsightedness in looking up for opportunities across the supply chain, technological constraints, lack of policy coordination for business innovation, economic recession induced by the COVID-19 pandemic and lack of incentives to change behavior from linear to circular economy are among the barriers pointed out. A systematic review of published literature in Australian context was conducted to assess the state-of-the art circular economy development. We have found that Australia has to look into overcoming the barriers by putting in place policies and guidelines to nurture the current synergies, business relationships and trust among the firms in partnership, and more R & D to meet the demand for complementing technologies and to have cohesion over the current CE strategies, among others.

Economical and environmental impacts of decarbonisation of Indonesian power sector.

Renewable energy has been prioritised in decarbonising Indonesia's electricity system. Indonesia aims to attain an efficient energy system by applying renewable energy tariffs that are lower than the cost of fossil fuel-generated electricity. However, the effectiveness of this policy is questionable, as renewable energy investments under previous premium feed-in tariffs did not meet expectations. This study aims to estimate generation costs from renewable energy expansions under three scenarios, namely existing power plant planning, and 11% and 14% emission reductions in Indonesia's electricity sector. We develop an agent-based model (ABM) tool called PowerGen-ABM that employs multi-approaches: linear programming and input-output analysis. The optimisation result shows that the emission reduction targets would increase the average electricity generation costs in 2028 from 65.3 USD/ MWh in the existing plan of power plant expansions to 68.3 USD/ MWh. The increased costs are caused by insufficient dispatchable renewables in several regions such as North Maluku. Renewable energy production share in total electricity production and emission reduction achievement of the existing plan in 2025 will be 22.8% and 6.5% below the targets of 23% and 11%, respectively. In contrast, the emission reduction scenarios could achieve those targets due to higher renewables productions, especially with wind energy from 5,268 GWh in the existing plan into anywhere between 64,472 to 75,085 GWh. Several policy implications are discussed based on these findings.

Enhancing the adaptive capacity for urban sustainability: A bottom-up approach to understanding the urban social system in China.

Solutions that effectively promote sustainable development in urban environments require an understanding of the complexity of human-environment interactions. This paper adopted a systems-based framework to understanding how social, organisational, and environmental factors interact within an urban system in China. Drawing upon a case study from the industrial city of Jinchang, it applied a qualitative bottom-up approach to understand these key factors operating from three perspectives: the commitment of stakeholders, institutional development and personal development of social systems. It revealed that decision-making mechanisms play a key role in improving the sustainability of governance, and that public-private cooperation and public participation are critical for innovative knowledge-based strategies. The key for improving institutional development is to reform the evaluation system of governance thus enhancing the capacities of decision and policy makers, and consequently improve the process of decision-making. Cultural and personal development are important soft power components that influence individual pro-environmental behaviour and performance toward sustainability. The results demonstrated how, in a Chinese context, the urban social system can be understood and urban sustainability can be promoted through environmental adaptation supported by joint efforts from governments, businesses, society and individuals. In this, China does not differ from other nations in spite of significant differences in cultural and political systems. This study contributed to a better understanding of complex urban systems, providing a bottom-up approach and knowledge for enhancing the adaptive capacity toward urban sustainability.

Estimating the impacts of financing support policies towards photovoltaic market in Indonesia: A social-energy-economy-environment model simulation.

This study develops a hybrid energy agent-based model that integrates the input-output analysis, environmental factors and socioeconomic characteristics of rural and urban households in Indonesia. We use the model to estimate the effects of four solar energy policy interventions on photovoltaic (PV) investments, government expenditure, economic outputs, CO2e emissions and the uses of steel, aluminium, concrete and energy. The results of our analysis call for the abolition of the PV donor gift policy, the improvement of production efficiency in the PV industry and the establishment of after-sales services and rural financing institutions. A 100 W peak (Wp) PV under this recommendation would be affordable for 80.6% of rural households that are projected to be without access to electricity in 2029. Net metering is the most effective policy for encouraging urban people to invest in PV in a situation where fossil energy prices are increasing and PV prices are declining. A donor gift policy may induce USD 51.9 new economic outputs for every Wp of PV operating to capacity in 2029, but would require a subsidy of USD 18.6/Wp. The recommended policies do not require subsidies and reduce CO2eq emissions and the consumption of aluminium, energy, steel and concrete by between 83.1% and 89.7% more than the existing policy. Several policy implications are discussed in response to these findings. As a contribution to energy modelling literature, the model can be used for other developing countries by merely changing its data.

A meta-analytic review of life cycle assessment and flow analyses studies of palm oil biodiesel.

This work reviews and performs a meta-analysis of the recent life cycle assessment and flow analyses studies palm oil biodiesel. The best available data and information are extracted, summarized, and discussed. Most studies found palm oil biodiesel would produce positive energy balance with an energy ratio between 2.27 and 4.81, and with a net energy production of 112 GJ ha(-1) y(-1). With the exception of a few studies, most conclude that palm oil biodiesel is a net emitter of greenhouse gases (GHG). The origin of oil palm plantation (planted area) is the foremost determinant of GHG emissions and C payback time (CPBT). Converting peatland forest results in GHG emissions up to 60 tons CO(2) equivalent (eq) ha(-1) y(-1) leading to 420 years of CPBT. In contrast, converting degraded land or grassland for plantation can positively offset the system to become a net sequester of 5 tons CO(2) eq ha(-1) y(-1). Few studies have discussed cradle-to-grave environmental impacts such as acidification, eutrophication, toxicity, and biodiversity, which open opportunity for further studies.

Improving the environmental profile of wood panels via co-production of ethanol and acetic acid.

The oriented strand board (OSB) biorefinery is an emerging technology that could improve the building, transportation, and chemical sectors' environmental profiles. By adding a hot water extraction stage to conventional OSB panel manufacturing, hemicellulose polysaccharides can be extracted from wood strands and converted to renewably sourced ethanol and acetic acid. Replacing fossil-based gasoline and acetic acid has the potential to reduce greenhouse gas (GHG) emissions, among other possible impacts. At the same time, hemicellulose extraction could improve the environmental profile of OSB panels by reducing the level of volatile organic compounds (VOCs) emitted during manufacturing. In this study, the life cycle significance of such GHG, VOC, and other emission reductions was investigated. A process model was developed based on a mix of laboratory and industrial-level mass and energy flow data. Using these data a life cycle assessment (LCA) model was built. Sensitive process parameters were identified and used to develop a target production scenario for the OSB biorefinery. The findings suggest that the OSB biorefinery's deployment could substantially improve human and ecosystem health via reduction of select VOCs compared to conventionally produced OSB, gasoline, and acetic acid. Technological advancements are needed, however, to achieve desirable GHG reductions.