877 resultados para electricity price markets
Resumo:
Although pumped hydro storage is seen as a strategic key asset by grid operators, financing it is complicated in new liberalised markets. It could be argued that the optimum generation portfolio is now determined by the economic viability of generators based on a short to medium term return on investment. This has meant that capital intensive projects such as pumped hydro storage are less attractive for wholesale electricity companies because the payback periods are too long. In tandem a significant amount of wind power has entered the generation mix, which has resulted in operating and planning integration issues due to wind's inherent uncertain, varying spatial and temporal nature. These integration issues can be overcome using fast acting gas peaking plant or energy storage. Most analysis of wind power integration using storage to date has used stochastic optimisation for power system balancing or arbitrage modelling to examine techno-economic viability. In this research a deterministic dynamic programming long term generation expansion model is employed to optimise the generation mix, total system costs and total carbon dioxide emissions, and unlike other studies calculates reserve to firm wind power. The key finding of this study is that the incentive to build capital-intensive pumped hydro storage to firm wind power is limited unless exogenous market costs come very strongly into play. Furthermore it was demonstrated that reserve increases with increasing wind power showing the importance of ancillary services in future power systems. © 2014 Elsevier Ltd. All rights reserved.
Resumo:
After the outbreak of war in 1914 and the subsequent blockade implemented by British navy, the German economy faced serious food shortages leading to famine-like conditions, especially towards the end of the war. As a response to these shortages, the German authorities introduced and implemented socialist policies such as price ceilings and food rations. This study focuses on the inefficient use of high-quality foodstuffs by members of lower social strata by discussing consumer decisions during the First World War from a microeconomic perspective. The German rationing system provided small, but valuable – measured by black market prices – quantities of superior foodstuffs. Especially meat could have been traded on flourishing black markets for greater quantities of inferior staple foods such as bread and potatoes. In this paper I argue that a more efficient use of rations by the poor could have improved their nutritional situation.
Resumo:
In a large scale survey of rice grains from markets (13 countries) and fields (6 countries), a total of 1578 rice grain samples were analysed for lead. From the market collected samples, only 0.6% of the samples exceeded the Chinese and EU limit of 0.2 μg g− 1 lead in rice (when excluding samples collected from known contaminated/mine impacted regions). When evaluating the rice grain samples against the Food and Drug Administration's (FDA) provisional total tolerable intake (PTTI) values for children and pregnant women, it was found that only people consuming large quantities of rice were at risk of exceeding the PTTI from rice alone. Furthermore, 6 field experiments were conducted to evaluate the proportion of the variation in lead concentration in rice grains due to genetics. A total of 4 of the 6 field experiments had significant differences between genotypes, but when the genotypes common across all six field sites were assessed, only 4% of the variation was explained by genotype, with 9.5% and 11% of the variation explained by the environment and genotype by environment interaction respectively. Further work is needed to identify the sources of lead contamination in rice, with detailed information obtained on the locations and environments where the rice is sampled, so that specific risk assessments can be performed.
Resumo:
The global financial crisis has led many regulators and lawmakers to a rethinking about current versus optimum financial market structures and activities that include a variety and even radical ideas about delevaraging and downsizing finance. This paper focuses on the flaws and shortcomings of regulatory reforms of finance and on the necessity of and scope for more radical transformative strategies. With 'crisis economics' back, the most developed countries, including the EU member states, are still on the edge of disaster and confronted with systemic risk. Changes in financial regulation adopted in the aftermath of the financial meltdown have not been radical enough to transform the overall system of finance-driven capitalism towards a more sustainable system with a more embedded finance. The paper discusses financialisation in order to understand the development trends in finance over the past decades and examines various theories to describe the typical trends and patterns in financial regulation. By focusing on a limited number of regulatory reforms in the European Union, the limitations of current reforms and the need for additional transformative strategies necessary to overcome the finance-driven accumulation regime are explored. Finally, the regulatory space for such transformative strategies and for taming finance in times of crisis, austerity, and increased public protest potential is analysed.
Resumo:
This article examines resource nationalism in sub-Saharan Africa's energy and minerals markets. It does so by exploring economic and political developments in three cases: Nigeria as an example of a petro-state established by means of expropriation in the wake of decolonisation; South Africa, a mature mining industry shaped by its settler colonial history; and Mozambique, a new and therefore highly-dependent entrant into the league of significant natural gas producers. Extractive industries have played a controversial role in sub-Saharan Africa due in particular to the prevalence of the resource curse. Nevertheless, energy exports will continue to play an important role in fuelling economic growth and, potentially, also development as new deposits of natural gas and oil are discovered across the region. Resource nationalism has, moreover, increasingly constrained operations of the traditionally dominant Western energy companies, in particular as competition from state-owned energy companies in sub-Saharan Africa and from emerging powers such as China is increasing.
Resumo:
This paper describes a fridge-freezer smart load model, which responds to external signals from the wholesale electricity market to support grid operations while switching the fridge-freezer on and off to maintain optimum operations for the owner. The key parameters of the model are the appliance dimensions, thermal mass, the fridge and freezer thermal time constants and the compressor power consumption. The model demonstrates that control strategies help to minimise load at times when the grid is under stress from high demand, and shift some load to a lower wholesale price or when there is excess renewable power. Three control strategies are proposed, based on peak shaving and valley filling, price signals and wind availability.
Resumo:
We analyze a two-stage quantity setting oligopolistic price discrimination game. In the first stage firms choose capacities and in the second stage they simultaneously choose the share that they assign to each segment. At the equilibrium the firms focus more on the high-valuation customers. When the capacities in the first stage are endogenous, the deadweight loss does not vanish with the level of price discrimination, as it does in one-stage games and monopoly. Moreover, the quantity-weighted average price increases with the level of price discrimination as opposed to established results in the literature for one-stage games.
Resumo:
Inter-dealer trading in US Treasury securities is almost equally divided between two electronic trading platforms that have only slight differences in terms of their relative liquidity and transparency. BrokerTec is more active in the trading of 2-, 5-, and 10-year T-notes while eSpeed has more active trading in the 30-year bond. Over the period studied, eSpeed provides a more pre-trade transparent platform than BrokerTec. We examine the contribution to ‘price discovery’ of activity in the two platforms using high frequency data. We find that price discovery does not derive equally from the two platforms and that the shares vary across term to maturity. This can be traced to differential trading activities and transparency of the two platforms.