Additional System Costs Research Articles

Exploring the demand for inter-annual storage for balancing wind energy variability in 100% renewable energy systems

As research in 100% renewable energy systems progresses, closing remaining research gaps, such as quantifying inter-annual balancing requirements, is necessary. For this study, inter-annual variations of wind power yield and the resulting balancing requirements are analysed for the energy transition towards 100% renewable energy of the United Kingdom and the Republic of Ireland. The energy system components are determined and cost implications are quantified comparing two options for inter-annual storage: e-hydrogen and e-methane for a low, medium, and high security case, which are expanded over ten years. The results indicate that more than 300 TWhth,LHV and 500 TWhth,LHV of inter-annual gas storage capacity in 2050 for the low and the high security case, respectively are required. For both investigated cases, the annual system costs increase notably compared to the reference scenario without inter-annual storage. For the case of e-hydrogen, the annualised system costs increase by 19% compared to an increase of 7% for e-methane for medium security cases. The difference in cost growth is due to significantly higher hydrogen underground storage costs that overcompensate additional system costs for e-methane production. This study provides an expansion from seasonal to inter-annual storage and a first estimate of inter-annual balancing requirements and costs.

Illustration of the Financial Impact of Usage of Initial Specimen Diversion Devices (ISDD) or Continued Educational Initiatives on the Costs from Blood Culture Contamination

Abstract Introduction/Objective Blood culture contamination (BCC) has the potential to lead to additional healthcare system costs and harm to patient. Two ways to reduce BCC have been explored in the literature and are economically modeled including initial specimen diversion devices (ISDD) and continued education on phlebotomy. Methods/Case Report A literature review on the economic costs of BCC, ISDD efficacy, and phlebotomy education to reduce BCC rates was undertaken. The reported average BCC at a veteran affairs medical center (VAMC), its reported rate during a month of phlebotomy training, the cost of an ISDD device at VAMC, and the average wage for 4 hours of phlebotomy manager time for training was noted. An illustrative economic model involving 100 patients was used at BCC rates of 1%, 2%, and 3% along with what had been observed at the VAMC was used for economic modeling. Results (if a Case Study enter NA) It was previously reported by Skoglund et al that in laboratories with rapid diagnostic testing modalities (such as MALDI-TOF or PCR testing), the cost per BCC event is $13,026 versus $8,287 in costs for a negative blood culture. ISDD efficacy in the literature reviewed (74.1% to 87.5%), continuous education efficacy (16.2% to 57.8%), ISDD device cost ($17.70 per device), and the hourly wage of a phlebotomy supervisor ($29.34) were noted. The reported average BCC rate from a regional VAMC was 1.33%, and during the month with education, the rate was 0.5%. From a model of 100 patients, ISDD device savings ranged from $1,741.60-$2,376.63 (1% BCR), $5,253.20-$6,523.25 (2% BCR), and $8,764.79-$10,669.88 (3% BCR). Education savings ranged from $755.98-$2,727.41 (1% BCR), $1,523.70-5,466.55 (2% BCR), and $2,291.42-$8,205.69 (3% BCR). The observed impact of education at the regional VAMC would have resulted in savings of $650.83 per 100 patients. Conclusion Both education and ISDD devices can result in significant savings from the costs of BCC.

Phase-Specific Healthcare Costs Associated With Giant Cell Arteritis in Ontario, Canada.

To estimate the additional healthcare system costs associated with giant cell arteritis (GCA) in the 1-year prediagnosis and postdiagnosis periods and over long-term follow-up compared to individuals with similar demographics and comorbidities without GCA. We performed a population-based study using health administrative data. Newly diagnosed cases of GCA (between 2002 and 2017 and aged ≥ 66 years) were identified using a validated algorithm and matched 1:6 to comparators using propensity scores. Follow-up data were accrued until death, outmigration, or March 31, 2020. The costs associated with care were determined across 3 phases: the year before the diagnosis of GCA, the year after, and ongoing costs thereafter in 2021 Canadian dollars (CAD). The cohort consisted of 6730 cases of GCA and 40,380 matched non-GCA comparators. The average age was 77 (IQR 72-82) years and 68.2% were female. A diagnosis of GCA was associated with an increased cost of CAD $6619.4 (95% CI 5964.9-7274.0) per patient during the 1-year prediagnostic period, $12,150.3 (95% CI 11,233.1-13,067.6) per patient in the 1-year postdiagnostic phase, and $20,886.2 (95% CI 17,195.2-24,577.2) per patient during ongoing care for year 3 onward. Increased costs were driven by inpatient hospitalizations, physician services, hospital outpatient clinic services, and emergency department visits. A diagnosis of GCA was associated with increased healthcare costs during all 3 phases of care. Given the substantial economic burden, strategies to reduce the healthcare utilization and costs associated with GCA are warranted.

Limitations and solutions of low cost virtual reality mirror therapy for post-stroke patients

Mirror therapy is applied to reduce phantom pain and as a rehabilitation technique in post-stroke patients. Using Virtual Reality and head-mounted displays this therapy can be performed in virtual scenarios. However, for its efficient use in clinical settings, some hardware limitations need to be solved. A new system to perform mirror therapy in virtual scenarios for post-stroke patients is proposed. The system requires the patient a standalone virtual reality headset with hand-tracking features and for the rehabilitator an external computer or tablet device. The system provides functionalities for the rehabilitator to prepare and follow-up rehabilitation sessions and a virtual scenario for the patient to perform rehabilitation. The system has been tested on a real scenario with the support of three experienced rehabilitators and considering ten post-stroke patients in individual sessions focused on upper limb motor rehabilitation. The development team observed all the sessions and took note of detected errors regarding technological aspects. Solutions to solve detected problems will be proposed and evaluated in terms of feasibility, performance cost, additional system cost, number of solved issues, new limitations, or advantages for the patient. Three types of errors were detected and solved. The first error is related to the position of the hands relative to the head-mounted display. To solve it the exercise area can be limited to avoid objectives that require turning the head too far. The second error is related to the interaction between the hands and the virtual objects. It can be solved making the main hand non-interactive. The last type of error is due to patient limitations and can be mitigated by having a virtual hand play out an example motion to bring the patient’s attention back to the exercise. Other solutions have been evaluated positively and can be used in addition or instead of the selected ones. For mirror therapy based on virtual reality to be efficient in post-stroke rehabilitation the current head-mounted display-based solutions need to be complemented with specific strategies that avoid or mitigate the limitations of the technology and the patient. Solutions that help with the most common issues have been proposed.

Nuclear Fusion impact on the requirements of power infrastructure assets in a decarbonized electricity system

Electrification of final energy use and electricity generation by low-carbon technologies are key points of the path toward carbon-neutrality. Carbon free electricity can be generated by both nuclear and renewable energy sources. Nevertheless, although all of them can be economically viable in terms of ‘Levelized Cost Of Energy‘, their exploitation involve variable renewables, so as to require power system upgrades with adequate energy storage systems, dispatchable generation capacity and transmission/distribution grid enhancements (power infrastructure assets) that may lead to relevant additional system costs. To this respect, each power system is almost unique, due to its peculiarities as far as renewable potentials is concerned. In order to find the least cost feasible and reliable generation mix, detailed hourly simulations are necessary. In this paper, long term power generation scenarios will be simulated with the COMESE code, a dispatch model able to perform detailed regional power systems analysis. Carbon-free Italian power system long term scenarios are simulated, with high share of photovoltaic and to less extent wind electricity together with a possible contribution of nuclear fusion power plants. The operation of the transmission grid is simulated, through a transport model, in order to assess the necessary grid enhancement and to estimate the related costs. In this context the impact of fusion will be assessed in terms of mitigation of the overall system cost of electricity.

Safety and savings from penicillin allergy de-labelling in pregnancy: good stewardship, good cents

Studies have shown that 80-95% of pregnant patients who report a penicillin allergy can be safely de-labelled. A pencillin allergy has been associated with poor obstetric outcomes, low rates of appropriate antibiotic prescribing and additional healthcare system costs. In a cohort of patients in British Columbia, Canada, who underwent penicillin de-labelling in pregnancy we present safety data and calculations of the lifetime savings following de-labelling.

An optimization model for the design of supply chains considering disruptions from pandemic uncertainty and infection trends

Supply chain design has been an extensively researched area of study especially given how companies all around the world seek to optimize system performance. The past years have highlighted the importance of creating lean supply chains in order to reduce costs and improve efficiency. However, the uncertainties brought by the COVID-19 pandemic have challenged global supply chains with constraints on labor and capacity. Decision makers are now focusing on creating a balance between agile and lean systems because of these disruptions. A mixed integer nonlinear programming (MINLP) model for the design of supply chains under a pandemic scenario has been developed in this regard. The model considers uncertainties brought about by the imposition of government restrictions on the operations of supply chains. Specifically, the model integrates forecasts on the likely degree of restrictions that may be imposed on a given network. It then examines the interdependency between infection trends and uncertainties on customer demand, operational capacity, and facility connections. Scenarios involving different infection trend types were used to test model behavior and variable relationships. The numerical experiments yielded results showing that supply chains need to anticipate and hedge against increasing infection trends. Failure to do so could lead to incurring as much as 18% in additional total system costs. The experiments further demonstrated that additional facilities with low setup costs but higher operating costs could be selected as insurance for possible declines in operating capacity or abrupt spikes in demand.

Cost-Effectiveness of Care Coordination for Children With Chronic Noncomplex Medical Conditions: Results From a Multicenter Randomized Clinical Trial

ObjectivesTo assess the cost-effectiveness of care coordination, compared with standard care, for children with chronic noncomplex medical conditions. MethodsA total of 81 children aged between 2 and 15 years newly diagnosed with a noncomplex chronic condition were randomized to either care coordination or standard care as part of a multicenter randomized controlled trial. Families receiving care coordination were provided access to an Allied Health Liaison Officer, who facilitated family-centered healthcare access across hospital, education, primary care, and community sectors. Costs were estimated over a 12-month period from the perspective of the Australian health system. Health outcomes were valued as quality-adjusted life-years (QALYs). Caregiver productivity costs were included in an alternative base-case analysis, and key assumptions were tested in a series of one-way sensitivity analyses. A probabilistic sensitivity analysis was conducted to investigate the overall impact of uncertainty in the data. ResultsChildren in the intervention arm incurred an average of $17 in additional health system costs (95% confidence interval −3861 to 1558) and gained an additional 0.031 QALYs (95% confidence interval −0.29 to 0.092) over 12 months, producing an incremental cost-effectiveness ratio of $548 per QALY. When uncertainty was considered, there was a 73% likelihood that care coordination was cost-effective from a health system perspective, assuming a willingness to pay of $50 000 per QALY. This increased to 78% when caregiver productivity costs were included. ConclusionsCare coordination is likely to be a cost-effective intervention for children with chronic noncomplex medical conditions in the Australian healthcare setting.

Polarization Fading Suppression for Optical Fiber Sensing: A Review

Optical fiber sensors are polarization sensitive and generally affected by polarization fading. This paper contributes to the optimal choice of polarization fading suppression methods for different optical fiber sensors, by means of comparative analysis of the mechanism of polarization fading, the strategy of polarization state control, and the applicability of suppression methods. The comparison results show that the polarization diversity receiving method is suitable for remote multi-channels optical fiber sensing system. The polarization orthogonal pulse pair method is only suitable for optical fiber sensing systems based on the backward scattering light. Meanwhile, the Faraday rotating mirror method is only suitable for optical fiber sensing systems based on the forward light interference. The polarization pulse coding method is suitable for sensing systems with high sensitivity and stability requirements. The polarization control method may increase the control complexity of sensing system for simultaneous variation of multiple polarization states. The full and partial polarization-maintaining fiber methods can be used to keep the polarization state of sensing light along the optical fiber, but the additional system cost limits the application. The polarization scrambler method is currently only available for sensing systems based on Brillouin scattering light. This paper provides a reference for the feasible selection of polarization fading suppression schemes for different optical fiber sensing systems.

Impact of Internal Carbon Prices on the Energy System of an Organisation’s Facilities in Germany, Japan and the United Kingdom Compared to Potential External Carbon Prices

Organisations attempt to contribute their share towards fighting the climate crisis by trying to reduce their emission of greenhouse gases effectively towards net zero. An instrument to guide their reduction efforts is internal carbon pricing. Next to choosing the right pricing tool, defining the exact value of an internal carbon price, especially against the background of potential regulatory external carbon prices, and assessing its impact on business units’ energy systems poses a challenge for organisations. The academic literature has so far not examined the impact differences of an internal carbon price across different countries, which this paper addresses by using an optimisation model. First, it analyses the energy system cost increase of a real-world facility based on an internal carbon price compared to a potential regulatory carbon price within a country. Second, we evaluate the energy system cost increase based on an internal carbon price across different countries. The results show that with regard to internal carbon prices the additional total system cost compared to potential external carbon prices stays within 9%, 15%, and 59% for Germany, Japan, and the United Kingdom, respectively. The increase in the energy system cost in each country varies between 3% and 93%. For all countries, the cost differences can be reduced by allowing the installation of renewables. The integration of renewables via energy storage and power-to-heat technologies depends on the renewable potentials and the availability of carbon capture and storage. If organisations do not account for these differences, it might raise the disapproval of internal carbon prices within the organisation.

Potential impact of COVID-19 related unemployment on increased cardiovascular disease in a high-income country: Modeling health loss, cost and equity.

BackgroundCardiovascular disease (CVD) is a leading cause of health loss and health sector economic burdens in high-income countries. Unemployment is associated with increased risk of CVD, and so there is concern that the economic downturn associated with the COVID-19 pandemic will increase the CVD burden.AimsThis modeling study aimed to quantify potential health loss, health cost burden and health inequities among people with CVD due to additional unemployment caused by COVID-19 pandemic-related economic disruption in one high-income country: New Zealand (NZ).MethodsWe adapted an established and validated multi-state life-table model for CVD in the national NZ population. We modeled indirect effects (ie, higher CVD incidence due to high unemployment rates) for various scenarios of pandemic-related unemployment projections from the NZ Treasury.ResultsWe estimated the potential CVD-related heath loss in NZ to range from 23,300 to 36,900 health-adjusted life years (HALYs) for the different unemployment scenarios. Health inequities would be increased with the per capita health loss for Māori (Indigenous population) estimated to be 3.7 times greater than for non-Māori (49.9 vs 13.5 HALYs lost per 1000 people). The estimated additional health system costs ranged between (NZ$303 million [m] to 503m in 2019 values; or US$209m to 346m).Conclusions and policy implicationsUnemployment due to the COVID-19 pandemic could cause significant health loss, increase health inequities from CVD, and impose additional health system costs in this high-income country. Prevention measures should be considered by governments to reduce this risk, including additional job creation programs and measures directed towards the primary prevention of CVD.

Fair Scheduling of Heterogeneous Customer Populations

When managing congested service systems, it is common to use priority rules based on some operational criteria. In this paper, we consider the societal implications of such individual-focused priority policies, when individuals are considered as members of broader population groups. We find that optimal resource allocation policies such as the cμ-rule in scheduling can lead to significant inequity across different population groups. We propose policies that can mitigate this inequity and can even generate completely equitable outcomes across populations with little, or at times, even no additional system cost. Thus, we find that it can be possible to achieve more equitable outcomes while ensuring operational efficiency.

Integrated assessment projections for the impact of innovation on CCS deployment in Europe

CCS is expected to play a sizeable role over the next several decades to drastically abate greenhouse gas emissions in the energy system by 2050. With the integrated assessment model TIAM-ECN we project how large its contribution could be in Europe in the power sector and industry, and analyze how this contribution may be affected by cost decline (driven by technological innovation) and ambitious greenhouse gas emission reduction targets. If Europe stays on track of achieving zero net emissions by mid-century, we find that CO2 capture activities in Europe may grow to a total amount of some 1700 MtCO2/yr in 2050. We project that by 2050 power plants equipped with CCS could contribute by approximately 25 % to total electricity generation, in competition with low-carbon alternatives such as nuclear energy and renewables like solar photovoltaic and wind power. CCS in association with the use of natural gas could account for about 35 % of energy use in industrial applications, while the use of biomass and coal combined with CCS could be employed for the production of hydrogen. We find that stringent climate policy measures constitute a bigger driver of broad CCS diffusion than CCS technology cost reductions. We project that under stringent climate policy targeting zero net emissions by 2050, a 30 % CCS capital cost reduction as a result of technological advancement could proffer Europe by the middle of the century a saving of about 17 billion US$/yr in additional energy system costs.

Assessing the impact of inertia and reactive power constraints in generation expansion planning

On the path towards power systems with high renewable penetrations and ultimately carbon-neutral, more and more synchronous generation is being displaced by variable renewable generation that does not currently provide system inertia nor reactive power support. This could create serious issues of power system stability in the near future, and countries with high renewable penetrations such as Ireland are already facing these challenges. Therefore, this paper aims at answering the questions of whether and how explicitly including inertia and reactive power constraints in generation expansion planning would affect the optimal capacity mix of the power system of the future. Towards this end, we propose the novel Low-carbon Expansion Generation Optimization model, which explicitly accounts for: unit commitment constraints, Rate of Change of Frequency inertia requirements and virtual inertia provision, and, a second-order cone programming approximation of the AC power flow, accounting for reactive power constraints. An illustrative case study underlines that disregarding inertia and reactive power constraints in generation expansion planning can result in additional system cost, system infeasibilities, a distortion of optimal resource allocation and inability to reach established policy goals.

A mathematical framework for measuring network flexibility

In the field of networking research, increased flexibility of new system architecture proposals, protocols, or algorithms is often stated to be a competitive advantage over its existing counterparts. However, this advantage is usually claimed only on an argumentative level and neither formally supported nor thoroughly investigated due to the lack of a unified flexibility framework. As we will show in this paper, the flexibility achieved by a system implementation can be measured, which consequently can be used to make different networking solutions quantitatively comparable with each other. The idea behind our mathematical model is to relate network flexibility to the achievable subset of the set of all possible demand changes, and to use measure theory to quantify it. As increased flexibility might come with additional system complexity and cost, our framework provides a cost model which measures how expensive it is to operate a flexible system. The introduced flexibility framework contains different normalization strategies to provide intuitive meaning to the network flexibility value as well, and also provides guidelines for generating demand changes with (non-)uniform demand utilities. Finally, our network flexibility framework is applied on two different use-cases, and the benefits of a quantitative flexibility analysis compared to pure intuitive arguments are demonstrated.

Energy transformation cost for the Japanese mid-century strategy

The costs of climate change mitigation policy are one of the main concerns in decarbonizing the economy. The macroeconomic and sectoral implications of policy interventions are typically estimated by economic models, which tend be higher than the additional energy system costs projected by energy system models. Here, we show the extent to which policy costs can be lower than those from conventional economic models by integrating an energy system and an economic model, applying Japan’s mid-century climate mitigation target. The GDP losses estimated with the integrated model were significantly lower than those in the conventional economic model by more than 50% in 2050. The representation of industry and service sector energy consumption is the main factor causing these differences. Our findings suggest that this type of integrated approach would contribute new insights by providing improved estimates of GDP losses, which can be critical information for setting national climate policies.

Keeping UAVs Under Control During GPS Jamming

Unmanned aerial vehicles (UAV) are being more and more widely deployed. Although, initially most UAVs were controlled by a pilot, autonomy has increased. This requires the flight controller in the UAV to accurately know the current system state. Knowing the current position is of crucial importance. Fortunately, this can be reliably obtained from a global navigation satellite system (GNSS) receiver. Recently, it was shown that criminal GNSS jamming frequently occurs. First, this paper analyzes the risk posed by off-the-shelf civilian GPS jammers to UAVs. Then, as the main contribution of this paper, a countermeasure is described and implemented using custom hardware and software that allows the control radio to be used as a backup navigation source. Finally, the proposed solution is tested in ideal and field conditions. It is shown that good performance can be obtained by the presented system, almost without additional system cost.

Do Kenya’s climate change mitigation ambitions necessitate large-scale renewable energy deployment and dedicated low-carbon energy policy?

In this paper Kenya’s climate change mitigation ambitions are analysed from an energy system perspective, with a focus on the role of renewable and other low-carbon energy technologies. At COP-21 in 2015 in Paris, Kenya has committed to a ‘nationally determined contribution’ of reducing domestic greenhouse gas emissions by 30% in 2030 in comparison to a business-as-usual projection. An efficient exploitation of the country’s renewable energy resources is key to achieving this target. We use the TIAM-ECN model to characterize plausible development pathways for the Kenyan energy mix until 2050 under different climate change mitigation scenarios. We conclude that the power sector can expand with mostly renewable energy options even in the absence of stringent greenhouse gas abatement targets. On the contrary, on the demand side a substantial deployment of low-carbon technologies is triggered only when ambitious emission reduction objectives are in place. The introduction of these technologies entails additional energy system costs, ranging in 2050 from 0.5% to 2% of the country’s GDP. Our analysis supports the feasibility of Kenyan climate management goals, provided that adequate investments in renewable and other low-carbon energy technologies are timely made available.

Robust Speed Sensorless Control to Estimated Error for PMa-SynRM

Recently, the permanent magnet-assisted synchronous reluctance motor (PMa-SynRM) that can replace induction motor has been more studying because of the needs of the high efficiency motor development for minimum energy performance standard. PMa-SynRM requires the speed and position information of rotor to control motor correctly. However, sensor for rotor information has many problems such as mounting space shortage and the additional system cost. Therefore, in this paper, the speed-sensorless control based on reference model adaptive control is introduced to eliminate the sensor. And mechanical design is improved for control. The proposed method is verified by simulation.

Modeling the patient and health system impacts of alternative xpert\xae MTB/RIF algorithms for the diagnosis of pulmonary tuberculosis in Addis Ababa, Ethiopia

BackgroundTo reduce global tuberculosis (TB) burden, the active disease must be diagnosed quickly and accurately and patients should be treated and cured. In Ethiopia, TB diagnosis mainly relies on spot-morning-spot (SMS) sputum sample smear analysis using Ziehl-Neelsen staining techniques (ZN). Since 2014 targeted use of xpert has been implemented. New diagnostic techniques have higher sensitivity and are likely to detect more cases if routinely implemented. The objective of our study was to project the effects of alternative diagnostic algorithms on the patient, health system, and costs, and identify cost-effective algorithms that increase TB case detection in Addis Ababa, Ethiopia.MethodsAn observational quantitative modeling framework was applied using the Virtual Implementation approach. The model was designed to represent the operational and epidemiological context of Addis Ababa, the capital city of Ethiopia. We compared eight diagnostic algorithm with ZN microscopy, light emitting diode (LED) fluorescence microscopy and Xpert MTB/RIF. Interventions with an annualized cost per averted disability adjusted life year (DALY) of less than the Gross Domestic Product (GDP) per capita are considered cost-effective interventions.ResultsWith a cost lower than the average per-capita GDP (US$690 for Ethiopia) for each averted disability adjusted life year (DALY), three of the modeled algorithms are cost-effective. Implementing them would have important patient, health system, and population-level effects in the context of Addis Ababa❖ The full roll-out of Xpert MTB/RIF as the primary test for all presumptive TB cases would avert 91170 DALYs (95% credible interval [CrI] 54888 – 127448) with an additional health system cost of US$ 11.6 million over the next 10 years. The incremental cost-effectiveness ratio (ICER) is $370 per DALY averted.❖ Same day LED fluorescence microscopy for all presumptive TB cases combined with Xpert MTB/RIF targeted to HIV-positive and High multidrug resistant (MDR) risk groups would avert 73600 DALYs( 95% CrI 48373 - 99214) with an additional cost of US$5.1 million over the next 10 years. The ICER is $169per DALY averted.❖ Same-day LED fluorescence microscopy for all presumptive TB cases (and no Xpert MTB/RIF) would avert 43580 DALYs with a reduction cost of US$ 0.2 million over the next 10years. The ICER is $13 per DALY averted.ConclusionsThe full roll-out of Xpert MTB/RIF is predicted to be the best option to substantially reduce the TB burden in Addis Ababa and is considered cost effective. However, the investment cost to implement this is far beyond the budget of the national TB control program. Targeted use of Xpert MTB/RIF for HIV positive and high MDR risk groups with same-day LED fluorescence microscopy for all other presumptive TB cases is an affordable alternative.