Congestion management in the deregulated electricity market: An assessment of locational pricing, redispatch and regulation

We analyze the fundamental differences between locational pricing and redispatch-based congestion management, followed by an assessment of their effects on grid operation and market efficiency. It is indicated that although optimal nodal pricing and congestion redispatch can provide equal results in terms of power injections, they are not equivalent in terms of short-run social welfare. Moreover, a modeling framework is presented to decouple and analyze the effects of transmission system operator/regulator and prosumer behavior on energy market efficiency in a transparent fashion. All results are illustrated on the basis of case studies for the IEEE 39-bus New England test network

Congestion management in the deregulated electricity market: an assessment of locational pricing, redispatch and regulation

We analyze the fundamental differences between locational pricing and redispatch-based congestion management, followed by an assessment of their effects on grid operation and market efficiency. It is indicated that although optimal nodal pricing and congestion redispatch can provide equal results in terms of power injections, they are not equivalent in terms of short-run social welfare. Moreover, a modeling framework is presented to decouple and analyze the effects of transmission system operator/regulator and prosumer behavior on energy market efficiency in a transparent fashion. All results are illustrated on the basis of case studies for the IEEE 39-bus New England test network

Survey of prevalence of protective and risk factors for SIDS in the Netherlands

BACKGROUND: From 1987 on, surveys have been conducted in the Netherlands to monitor babycare habits and target safe sleeping prevention campaigns. The last survey was conducted in 2011. In the Netherlands, the 2016 incidence of SIDS (R95) was 0.075/1000 live births (n=13); taking into account adjacent categories the SUDI incidence was 0.15/1000 (n=26). This low incidence, the lowest in the Western world, may result in decreased parental awareness of SIDS risks and complacency regarding preventive messages. Therefore, a new survey was conducted. OBJECTIVES: 1) To measure the prevalence of protective and risk factors for SIDS in the Netherlands in 2017 including new customs of babycare. 2) To compare 2011 prevalences with 2017. 3) To investigate why parents do not follow recommendations regarding safe sleep position and location. METHODS: A cross-sectional study was conducted using an online questionnaire (52 questions). The study population encompassed parents/caregivers of infants up to 1 year of age living in the Netherlands. Between February 12 – April 30, 2017, invitations with a link to the questionnaire were distributed to 9000 parents visiting 17 child healthcare organizations. In healthcare centers in socially more deprived neighborhoods research assistants helped parents fill out the online questionnaire. In May and June, invitations to participate were also communicated using social media. We used SPSS 24 to calculate prevalence rates and performed a content analysis of answers on open-ended questions on reasons for not following SIDS prevention advice. RESULTS: In total 1289 questionnaires were filled out, of which 80 were excluded, mostly because the child was too old. The study population was comparable to the Dutch population in terms of sex ratio, preterm infants, and parents with a lower education. First-born infants and parents with a higher education were overrepresented, families with a migration background were underrepresented. Sleeping prone increased from 3.1% of infants when 0-2 months old to 13.6% at 9-11 months. Infants aged 0-2 months slept in a separate room in 31.5%, roomshared with parents in 52.3%, slept in an attached bedside sleeper in 9.7% and with their parent(s) in bed in 6.3%. For age 7-8 months this was respectively 71.2%, 15.2%, 4.0% and 8%. Only 4.5% of infants used a duvet. The typical Dutch sleeping sack (wearable blanket) was used for 55.8% of infants. Only 50% of infants 0-2 months and 23.6% of infants 5-6 months were breastfed exclusively. Of all mothers, 4z had smoked during pregnancy; of all infants 21.3% were exposed to parents’ smoking. CONCLUSIONS: The number of infants that sleep prone is comparable to 2011, with still significant room for improvement. Roomsharing with infants 0-2 months has increased significantly since 2011, but so has bedsharing. These data are important for future preventive campaigns

Experimentally increased brood size accelerates actuarial senescence and increases subsequent reproductive effort in a wild bird population

The assumption that reproductive effort decreases somatic state, accelerating ageing, is central to our understanding of life-history variation. Maximal reproductive effort early in life is predicted to be maladaptive by accelerating ageing disproportionally, decreasing fitness. Optimality theory predicts that reproductive effort is restrained early in life to balance the fitness contribution of reproduction against the survival cost induced by the reproductive effort. When adaptive, the level of reproductive restraint is predicted to be inversely linked to the remaining life expectancy, potentially resulting in a terminal effort in the last period of reproduction. Experimental tests of the reproductive restraint hypothesis require manipulation of somatic state and subsequent investigation of reproductive effort and residual life span. To our knowledge the available evidence remains inconclusive, and hence reproductive restraint remains to be demonstrated. We modulated somatic state through a lifelong brood size manipulation in wild jackdaws and measured its consequences for age-dependent mortality and reproductive success. The assumption that lifelong increased brood size reduced somatic state was supported: Birds rearing enlarged broods showed subsequent increased rate of actuarial senescence, resulting in reduced residual life span. The treatment induced a reproductive response in later seasons: Egg volume and nestling survival were higher in subsequent seasons in the increased versus reduced broods' treatment group. We detected these increases in egg volume and nestling survival despite the expectation that in the absence of a change in reproductive effort, the reduced somatic state indicated by the increased mortality rate would result in lower reproductive output. This leads us to conclude that the higher reproductive success we observed was the result of higher reproductive effort. Our findings show that reproductive effort negatively covaries with remaining life expectancy, supporting optimality theory and confirming reproductive restraint as a key factor underpinning life-history variation