Probabilistic techno-economic assessment of anaerobic digestion predicts economic benefits to smallholder farmers with quantifiable certainty

The paper deals with the performances of the mesophilic anaerobic digestion treatment of sewage sludge from a full scale BNR process without primary settling (nominally 300,000 PE). A relation between the activated sludge observed yields, Yobs, and the anaerobic digester performance was preliminarily found: for values of Yobs of 0.25 kgVSS/kgCOD the anaerobic digester specific gas production showed the best performances (0.22 m3/kgVSfed). This has to be confirmed with wider future studies. It was also shown the level of sludge pre-thickening to be reached for the self-sustaining warming of the digester also in wintertime. According to the energetic balance and to a comparison with an aerobic stabilisation process, it was pointed out as when a co-generation unit for heat and energy production was introduced about 3.4 kWh/PE y of energy were produced in the anaerobic digestion process. On the other hand, 4.3 kWh/PE y were spent if an aerobic stabilisation process was applied. The economic assessment, carried out on the basis of the energy balances, showed that the anaerobic digestion is always economically advantageous if compared to aerobic stabilisation processes, also for small WWTPs. According to the energetic evaluations an environmental balance was assessed, in terms of CO2 emissions. The difference between anaerobic and aerobic processes was about 5.3 kgCO2/PE y in favour of anaerobic processes application.

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Economic assessment of urban space and blue-green infrastructure in Singapore

Journal of Urban Ecology ◽

10.1093/jue/juab020 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Mabel Lim ◽

Stefanos Xenarios

Keyword(s):

Urban Space ◽

Green Infrastructure ◽

Life Quality ◽

Economic Assessment ◽

Well Being ◽

Pilot Project ◽

Economic Benefits ◽

Mean Value ◽

Urban Environments ◽

Urban Greenery

Abstract The urban conglomeration has accentuated the role of urban greenery as a determinant factor for sustainable living, especially in highly dense cities. The country of Singapore has consistently attempted to develop and rehabilitate urban greenery by attempting to align the green space policy with the pursuit of better life quality. In this study, we assess the benefits arising from the rehabilitated Bishan-Ang Mo Kio (AMK) Park in north Singapore and the effects on economic welfare. The Bishan-AMK Park was initially constructed in the late 70 s as a drainage area for the avoidance of flooding incidents. In 2012, a pilot project was introduced to create a blue-green infrastructure (BGI) space for the provision of drainage and flood prevention but also for recreational and environmental improvement in the area. Yet, the benefits emerging from BGI are not well explored and still underestimated. To this extent, we evaluate selected services related to recreational, socio-cultural and tourism-related values by indicating the economic benefits from the introduction of BGI in condensed urban environments like Singapore. The findings indicate that the benefits deriving from the selected services could be within the range of US$100 million to US$220 million with a mean value of US$160 million per year by substantially contributing to human well-being. The assessment of environmental services can raise the awareness of residents and local authorities on the contribution of urban greenery to livelihoods and economic development in Singapore and similar densely populated areas.

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Safety and Economic Assessment of Converting Two-Way Stop-Controlled Intersections to Roundabouts on High Speed Rural Highways

Journal of the Transportation Research Forum ◽

10.5399/osu/jtrf.54.1.4279 ◽

2015 ◽

Author(s):

Shanshan Zhao ◽

Aemal J. Khattak ◽

Eric C. Thompson

Keyword(s):

High Speed ◽

Empirical Bayes ◽

Evaluation Method ◽

Economic Assessment ◽

Economic Benefits ◽

Traffic Data ◽

Property Damage ◽

Rural Highways ◽

Monetary Value ◽

Safety Improvement

This research addressed two questions: “Are roundabouts on rural high-speed roadways safer than two-way stop controlled (TWSC) intersections?” and “What economic benefits can be expected from converting TWSC intersections to roundabouts in terms of safety improvement?” Crash and traffic data on four TWSC intersections that were converted to roundabouts in Kansas were analyzed using the empirical Bayes before-after evaluation method and crash costs were applied to evaluate economic benefits. Analysis showed that fatal, non-fatal, and property-damage-only crashes were reduced by 100%, 76.47%, and 35.49%, respectively. The annual monetary value from this reduction was between $1.0—$1.6 million in 2014 dollars.

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Technical and Economic Assessment on Various Energy-Saving Reconstruction of Public Buildings

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.368-370.1289 ◽

2013 ◽

Vol 368-370 ◽

pp. 1289-1295

Author(s):

Ren Jun ◽

Peng Wang ◽

Xiang Yang Jiang

Keyword(s):

Energy Saving ◽

Net Present Value ◽

High Efficiency ◽

Cost Benefit ◽

Economic Assessment ◽

Economic Benefits ◽

Public Buildings ◽

Benefit Ratio ◽

Financial Assessment ◽

Cost Benefit Ratio

The Paper, based on the theory of technical and economic assessment, puts forward to make financial assessment (on net present value, payback time, risk-benefit ratio, etc.) as the economic control index in accordance with the ideology of entire life cycle during the energy-saving reconstruction of public buildings. Then the Paper makes analysis on cost-benefit ratio of energy-saving reconstruction measures taken on various parts and equipment of outer protective structure, finds out approaches to energy-saving reconstruction with high efficiency, and finally adopts the method of sensitivity analysis on individual energy-saving reconstruction measures to further optimize reconstruction plan, thus improving economic benefits of energy saving.

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Operation and Economic Assessment of Hybrid Refueling Station Considering Traffic Flow Information

Energies ◽

10.3390/en11081991 ◽

2018 ◽

Vol 11 (8) ◽

pp. 1991 ◽

Cited By ~ 5

Author(s):

Suyang Zhou ◽

Yuxuan Zhuang ◽

Wei Gu ◽

Zhi Wu

Keyword(s):

Energy Storage ◽

Traffic Flow ◽

Storage System ◽

Economic Assessment ◽

Energy Storage System ◽

Economic Benefits ◽

Green Energy ◽

Fuel Cell Vehicle ◽

Management Approach ◽

Hydrogen Pumps

It is anticipated that the penetration of “Green-Energy” vehicles, including Electric Vehicle (EV), Fuel Cell Vehicle (FCV), and Natural Gas Vehicle (NGV) will keep increasing in next decades. The demand of refueling stations will correspondingly increase for refueling these “Green-Energy” vehicles. While such kinds of “Green-Energy” vehicles can provide both social and economic benefits, effective management of refueling various kinds of these vehicles is necessary to maintain vehicle users’ comfortabilities and refueling station’s return on investment. To tackle these problems, this paper proposes a novel energy management approach for hybrid refueling stations with EV chargers, Hydrogen pumps and gas pumps. Firstly, the detailed models of EV chargers, Hydrogen pumps with electrolyte and hydrogen tank, the gas pumps with gas tank, renewable resources, and battery energy storage systems are established. The forecasting methodologies for renewable energy, electricity price and the traffic flow are also presented to support the hybrid refueling station modeling and operation. Then, a management approach is adopted to manage the refueling various kinds of vehicles with considerations of the refueling station profitability. Finally, the proposed management approach is verified under four different kinds of tariffs- Economy-7, Economy-10, Flat-rate, and Real-Time Pricing (RTP), finding that the proposed management approach has the best performance under RTP tariff. The economic assessment of the Energy Storage System (ESS) is also performed. It is found that the ESS can make the saving up to $127 per day. Different sizes of gas storage tank are compared in the final section as well. The result shows that increasing the size of the tank does not bring attractive extra benefits with the consideration of the investment on enlarging the tank size.

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Rainwater harvesting as an alternative for water supply in regions with high water stress

Water Science & Technology Water Supply ◽

10.2166/ws.2018.018 ◽

2018 ◽

Vol 18 (6) ◽

pp. 1946-1955 ◽

Cited By ~ 3

Author(s):

Miguel Ángel López Zavala ◽

Mónica José Cruz Prieto ◽

Cristina Alejandra Rojas Rojas

Keyword(s):

Water Demand ◽

Rainwater Harvesting ◽

Economic Assessment ◽

Water Source ◽

High Water ◽

Economic Benefits ◽

Storage Tanks ◽

Logistics Company ◽

Current Water

Abstract In this study, the reliability of using rainwater harvesting to cover the water demand of a transportation logistics company located in Mexico City was assessed. Water consumption in facilities and buildings of the company was determined. Rainwater potentially harvestable from the roofs and maneuvering yard of the company was estimated based on a statistical analysis of the rainfall. Based on these data, potential water saving was determined. Characterization of rainwater was carried out to determine the treatment necessities for each water source. Additionally, the capacity of water storage tanks was estimated. For the selected treatment systems, an economic assessment was conducted to determine the viability of the alternative proposed. Results showed that current water demand of the company can be totally covered by using rainwater. The scenario where roof and maneuvering yard rainwater was collected and treated together resulted in being more economic than the scenarios where roof and maneuvering yard rainwater was collected and treated separately. Implementation of the rainwater harvesting system will generate important economic benefits for the company. The investment will be amortized in only 5 years and the NPV will be on the order of US$ 5,048.3, the IRR of 5.7%, and the B/I of 1.9.

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