Break-even Selling Price Research Articles

Pre-combustion carbon-capture technologies for power generation: an engineering-economic assessment

SUMMARY An engineering-economic analysis of the behaviours of each of two pre-combustion gas-turbine combined cycles with CO2 capture (an Integrated Gasification Combined Cycle (IGCC) and an Integrated Reforming Combined Cycle (IRCC)) is described. Their economic performances have been evaluated in terms of the break-even electricity selling price. The results show that the proposed pre-combustion power plant efficiency values (37% and 43.7% for the IGCC and the IRCC respectively) are significantly lower compared to a conventional plant value (55.3%). The CO2 emissions of the latter are less than half those of the conventional plant. Introducing an hypothetical carbon tax equal to 50£/tCO2, the break-even selling price (BESP) for the proposed IGCC and IRCC plants is 4.40 p/kWh and 4.10 p/kWh respectively, while for the conventional plant amounts to 4.73 p/kWh. A sensitivity analysis has been carried out by varying the most influential investment parameters. The analysis has revealed that, considering the uncertainties associated with these key parameters, a substantial risk that the BESP could exceed the first value obtained is so prominent in some cases to alter their ranking order with respect to the most competitive technology. The final part of the analysis is a Monte-Carlo simulation to determine the impact of simultaneous variations of all the variables, subject to uncertainty, on the break-even selling unit price for the generated electricity. From the simulation, it derives that the BESP value ranges from 3.13 p/kWh to over 6.00 p/kWh for the IGCC case with a 50% probability of exceeding the first value obtained (4.40 p/kWh). In the IRCC case, the range of possible value for the BESP is from 2.85 p/kWh to 6.10 p/kWh, and there is a 60% probability that the actual BESP would exceed the first value obtained (4.10 p/kWh). Copyright © 2013 John Wiley & Sons, Ltd.

Comparison of Two Weaning Dates and Two Finishing Systems on Feedlot Performance, Carcass Characteristics, and Enterprise Profitability of Fall-born Steers

ABSTRACT In a 3-yr study, 139 fall-born steers (Angus and Angus x Charolais; BW = 287 ± 31 kg in mid-April) were allotted to 1 of 4 treatments in a 2 x 2 factorial arrangement. Weaning date treatments were 1) mid-April at 212 ± 12 d of age (normal weaning; NW) and 2) mid-July at 300 ± 15 d of age (late weaning). Finishing system treatments were feedlot placement in 1) July, with a mean calf age of 310 ± 14 d (calf-fed; CF), and 2) October, with a mean calf age of 394 ± 15 d (yearling-fed; YF). Steers assigned to the NW treatment were returned to native tall grass prairie rangeland after weaning each year. Steers assigned to the YF treatment grazed abundant native tall grass prairie pasture for an additional 84-d period. The number of days on feed was greater (P 0.05) for time of weaning were detected, nor were there any interactions (P > 0.05) between weaning and finishing system. Yearling-fed steers were heavier (34 kg; P 0.05) were detected for any carcass traits measured. System economic analysis showed no differences in break-even selling price or system profitability.

Performance, Carcass Characteristics, and Economic Analysis of Calf-Fed and Wheat Pasture Yearling Systems in the Southern Great Plains

AbstractModerate-framed Angus steers from a single cow herd were utilized in a 2-yr study that evaluated performance, carcass traits, and production economics of calf-fed vs. yearling systems. After a brief preconditioning period, weaned steer calves were placed on a high concentrate finishing diet (CF; n = 63) or grazed wheat pasture 164 d before feedlot entry (YF; n = 62). Resulting feedlot entry weight and days on feed were 228kg and 169 d, respectively, for CF and 445kg and 88 d, respectively, for YF. Final BW for YF was 87kg heavier than CF (P < 0.01). For YF, ADG and DMI was greater and G:F was less than CF steers (P < 0.05). Hot carcass weight was 55kg greater and LM area was 8cm2 larger for YF compared with CF steers (P < 0.01). Dressing percentage was not different between systems (P = 0.90). System did not affect 12th-rib fat, USDA YG, or marbling score (P > 0.27). Profitability tended (P = 0.09) to favor the CF over the YF system, although breakeven selling price was greater (P < 0.01) for CF vs. YF. Live and carcass price was greater (P = 0.02) for the CF system. Net profit for CF and YF was not different (P > 0.10) when quality or yield grid markets were applied. Inclusion of a long-term winter wheat grazing period increased hot carcass weight by 17% with no detrimental effects on carcass characteristics.

A techno-economic analysis of the application of continuous staged-combustion and flameless oxidation to the combustor design in gas turbines

The impact of NO x reduction technologies upon a gas turbine power station has been investigated using the ECLIPSE process simulator. Technical, environmental and economic assessments were performed, based upon a model of the simple cycle gas turbine, fuelled by natural gas. The technologies assessed were: a) selective catalytic reduction (SCR); b) continuous staged air combustion (COSTAIR); and c) flameless oxidation method (FLOX). The SCR method produced a 90% reduction of NO x emissions, at an additional penalty to the electricity cost of 0.19–0.20 p/kWh, over the base case of simple cycle with standard combustor. The COSTAIR method reduced 80.4% of NO x emissions, at an additional electricity cost of 0.03–0.04 p/kWh, over the base case; but 0.16–0.17 p/kWh less than the SCR method at a slightly higher level of NO x emissions. The FLOX method generated 92.3% less of NO x emissions, at an additional electricity cost of 0.08–0.11 p/kWh, over the base case; but 0.09–0.11 p/kWh less than the SCR method at a lower level of NO x emissions. A sensitivity analysis of the Break-Even Selling Price (BESP) of electricity and the Specific Investment (SI) versus the cost of different burner systems shows that the SCR system had the highest values for BESP and SI; and the COSTAIR system had the lowest. The results show that the use of these non-standard burners could offer an effective method of reducing NO x emissions considerably for simple cycle gas turbine power plants with minimal effect on system capital cost and electricity selling price, and were also cheaper than using SCR.

Industrial Production of Polyhydroxyalkanoates Using Escherichia Coll: An Economic Analysis

Disposal of plastic, in particular packaging, is a serious problem confronting many countries. Part of a solution lies in using biodegradable plastics such as polyhydroxyalkanoates (PHAs), which can be produced by bacterial fermentation. This paper presents an economic analysis of PHA production by fermentation using recombinant Escherichia coli , in order to identify areas where significant cost reductions are possible. Based on an annual production of 4300 tonnes of poly-hydroxybutyrate (PHB) from glucose supplemented with complex nitrogen sources, the break-even selling price per kilogram of plastic is US1995$6.08. A ten year plant life, 40% tax rate, 10% discount rate and a conservative process design based on existing technology are assumed. This cost is highly sensitive to PHB expression level and recovery strategy, and moderately sensitive to medium cost and cell growth yield on glucose. Maximum cell density achieved has little effect for the process design used in this analysis. At the same level of production, the cost can be easily reduced to between US1995$5.63kg −1 and US1995$3.59kg −1 by using dairy whey as a partial replacement for glucose as the carbon source. The price variation represents different constraints on whey availability and credits for whey disposal. Further price reduction will require significant changes to existing process technology. For example, a scenario incorporating 60% glucose substitution with concentrated dairy whey and a significantly altered processing strategy has the potential to reduce PHB production cost to US1995$2.67kg −1 . Significant work remains to develop and optimize such cost-effective designs.