Renewable energy production and demand dataset for the energy system of Colombia

During the last decades, an increasing number of studies have focused their attention on the development of energy system models in order to facilitate sustainable energy planning strategies and understand the technical challenges associated with the integration of renewable energy sources. However, these models usually require detailed and large amount of data as inputs. The data presented in this article provides key inputs and modelling assumptions adopted in the research paper titled “Large scale integration of renewable energy sources (RES) in the future Colombian energy system” [1]. These datasets can be used by researchers and policymakers in order to analyse different pathways oriented to the development of low carbon strategies for Colombia and countries with similar energy systems

The impact of rate design and net metering on the bill savings from distributed PV for residential customers in California

Net metering has become a widespread policy in the U.S. for supporting distributed photovoltaics (PV) adoption. Though specific design details vary, net metering allows customers with PV to reduce their electric bills by offsetting their consumption with PV generation, independent of the timing of the generation relative to consumption - in effect, compensating the PV generation at retail electricity rates (Rose et al. 2009). While net metering has played an important role in jump-starting the residential PV market in the U.S., challenges to net metering policies have emerged in a number of states and contexts, and alternative compensation methods are under consideration. Moreover, one inherent feature of net metering is that the value of the utility bill savings it provides to customers with PV depends heavily on the structure of the underlying retail electricity rate, as well as on the characteristics of the customer and PV system. Consequently, the value of net metering - and the impact of moving to alternative compensation mechanisms - can vary substantially from one customer to the next. For these reasons, it is important for policymakers and others that seek to support the development of distributed PV to understand both how the bill savings varies under net metering, and how the bill savings under net metering compares to other possible compensation mechanisms. To advance this understanding, we analyze the bill savings from PV for residential customers of California's two largest electric utilities, Pacific Gas and Electric (PG&E) and Southern California Edison (SCE). The analysis is based on hourly load data from a sample of 215 residential customers located in the service territories of the two utilities, matched with simulated hourly PV production for the same time period based on data from the nearest of 73 weather stations in the state

Validation of Non-Traditional Approaches to Annual Average Daily Traffic (AADT) Volume Estimation

For this validation study, NREL compiled traffic volume data from permanent traffic counters at over 500 locations across the U.S. These data were used to validate annual average daily traffic (AADT) estimates developed by Streetlight Data using passive data sources. The analysis revealed a strong correlation between estimates derived from passive sources and the permanent counters. However, statistical differences were observed, and deviations from ground truth may be unacceptable for some applications. Toll locations were particularly prone to high errors, possibly due to complex geometry. While the validation sheds light on the utility of AADT estimation from passive sources, its findings were limited by a lack of permanent counter data. It is possible that an analysis using a larger sample size could result in more robust findings

Environmental and financial implications of ethanol as a bioethylene feedstock versus as a transportation fuel

Bulk chemicals production from biomass may compete with biofuels for low-cost and sustainable biomass sources. Understanding how alternative uses of biomass compare in terms of financial and environmental parameters is therefore necessary to help ensure that efficient uses of resources are encouraged by policy and undertaken by industry. In this paper, we compare the environmental and financial performance of using ethanol as a feedstock for bioethylene production or as a transport fuel in the US life cycle-based models are developed to isolate the relative impacts of these two ethanol uses and generate results that are applicable irrespective of ethanol production pathway. Ethanol use as a feedstock for bioethylene production or as a transport fuel leads to comparable greenhouse gas (GHG) emissions and fossil energy consumption reductions relative to their counterparts produced from fossil sources. By displacing gasoline use in vehicles, use of ethanol as a transport fuel is six times more effective in reducing petroleum energy use on a life cycle basis. In contrast, bioethylene predominately avoids consumption of natural gas. Considering 2013 US ethanol and ethylene market prices, our analysis shows that bioethylene is financially viable only if significant price premiums are realized over conventional ethylene, from 35% to 65% depending on the scale of bioethylene production considered (80 000 t yr−1 to 240 000 t yr−1). Ethanol use as a transportation fuel is therefore the preferred pathway considering financial,GHGemissions, and petroleum energy use metrics, although bioethylene production could have strategic value if demand-side limitations of ethanol transport fuel markets are reached

Consolidated briefing of biochemical ethanol production from lignocellulosic biomass

AbstractBioethanol production is one pathway for crude oil reduction and environmental compliance. Bioethanol can be used as fuel with significant characteristics like high octane number, low cetane number and high heat of vaporization. Its main drawbacks are the corrosiveness, low flame luminosity, lower vapor pressure, miscibility with water, and toxicity to ecosystems. One crucial problem with bioethanol fuel is the availability of raw materials. The supply of feedstocks for bioethanol production can vary season to season and depends on geographic locations. Lignocellulosic biomass, such as forest-based woody materials, agricultural residues and municipal waste, is prominent feedstock for bioethanol cause of its high availability and low cost, even though the commercial production has still not been established. In addition, the supply and the attentive use of microbes render the bioethanol production process highly peculiar. Many conversion technologies and techniques for biomass-based ethanol production are under development and expected to be demonstrated. In this work a technological analysis of the biochemical method that can be used to produce bioethanol is carried out and a review of current trends and issues is conducted

Habilidades funcionais, nível de actividade, integração na comunidade e saúde em idosos institucionalizados em lar: resultados preliminares

São escassos os estudos portugueses que avaliam o nível de funcionalidade, o nível de actividade e a saúde em idosos institucionalizados em lar. Objectivos: Estimar os meses de institucionalização dos idosos e as causas que conduziram à institucionalização em lar, bem como o número de idosos que partilha o seu quarto com outros. Estimar as Habilidades Funcionais dos idosos, o tipo de actividades relatadas, dentro e fora da instituição (Nível de Actividade e Integração na Comunidade) e o grau de saúde (objectiva e subjectiva). Analisar a relação entre estas quatro dimensões e analisar a relação destas com algumas variáveis demográficas (idade, género). Métodos: 35 idosos institucionalizados em lar (idade média=80.20 anos; DP=6.263) completaram o Questionário de Informação Pessoal (QIP; Fernándes-Ballesteros, 1995; Maia et al., 2013). Para a análise dos dados recorremos ao SPSS 21. Resultados: A grande generalidade dos idosos está institucionalizada há mais de 16 meses, por motivos maioritariamente de saúde (65,7%), partilha o quarto com terceiros (71.4%) e é autónoma, não necessitando de ajuda (56.7%) em actividades como o cuidado pessoal, comer, vestir/despir, andar, levantar/deitar. Quando se trata das actividades mais complexas, como a administração de dinheiro, uso do telefone ou ida às compras, o grau de dependência aumenta (27.6% dos sujeitos necessitam de muita ajuda e 35.2% de alguma ajuda). Verifica-se que 72.9% da população está inactiva, visto limitar-se a ver televisão ou a ouvir rádio e apenas 14.3% dos idosos se dedicam a actividades fora da Instituição. Os actos religiosos têm uma larga adesão (88.6%). 79.4% dos idosos reporta problemas de mobilidade e 35.3% problemas de foro psicológico. Verifica-se que 45.7% percepcionam a saúde como má, com as mulheres a percepcionarem a sua saúde mais negativamente do que os homens. Nenhum dos idosos, de ambos os géneros, percepciona a sua saúde como boa ou excelente (0%). A dimensão Nível de Actividade apresenta uma correlação positiva com a dimensão Integração na Comunidade (r=.448*). O género apresenta uma correlação significativa com a dimensão Habilidades Funcionais (rho=.383*) e com a dimensão Saúde (r=.414*). O estado civil apresentou uma correlação positiva com as Habilidades Funcionais (rho=.419*) e o grau de escolaridade apresentou uma correlação negativa e com a dimensão Saúde (r=-.446*). Conclusões: Na nossa amostra a institucionalização é causada maioritariamente devido a problemas de saúde. A maioria dos idosos partilha o seu quarto o que pode afectar a sua intimidade e bem-estar. Apesar da maioria dos idosos ser funcionalmente autónoma, a grande generalidade apresenta uma vida pautada pela inactividade e por fracos laços com o exterior. As mulheres percepcionam a sua saúde mais negativamente do que os homens. Importa assim, desenvolver estratégias que conduzam a um envelhecimento activo destes idosos