Arbitrage with Power Factor Correction using Energy Storage

The importance of reactive power compensation for power factor (PF) correction will significantly increase with the large-scale integration of distributed generation interfaced via inverters producing only active power. In this work, we focus on co-optimizing energy storage for performing energy arbitrage as well as local power factor correction. The joint optimization problem is non-convex, but can be solved efficiently using a McCormick relaxation along with penalty-based schemes. Using numerical simulations on real data and realistic storage profiles, we show that energy storage can correct PF locally without reducing arbitrage profit. It is observed that active and reactive power control is largely decoupled in nature for performing arbitrage and PF correction (PFC). Furthermore, we consider a real-time implementation of the problem with uncertain load, renewable and pricing profiles. We develop a model predictive control based storage control policy using auto-regressive forecast for the uncertainty. We observe that PFC is primarily governed by the size of the converter and therefore, look-ahead in time in the online setting does not affect PFC noticeably. However, arbitrage profit are more sensitive to uncertainty for batteries with faster ramp rates compared to slow ramping batteries.Comment: 10 pages, 8 figure

Modelling and measuring price discovery in commodity markets

In this paper we present an equilibrium model of commodity spot (St) and future (Ft) prices, with finite elasticity of arbitrage services and convenience yields. By explicitly incorporating and modeling endogenously the convenience yield, our theoretical model is able to capture the existence of backwardation or contango in the long-run spot-future equilibrium relationship, (St-ß2Ft ). When the slope of the cointegrating vector ß2>1 (ß2

Regulatory reform in Mexico's natural gas industry : liberalization in the context of a dominant upstream incumbent

The natural gas industry combines activities with natural monopoly characterisitics with those that are potentially competitive. Pipeline transport and distribution, which have natural monopoly characterisitcs, require regulation of price and non-price behavior. Production is a contestable activity, but in a few countries (including Mexico) it remains a state monopoly. Gas marketing is also contestable, but the presence of a dominant, upstream, vertically integrated incumbent may pose significant barriers to entry. Market architecture decisions--such as horizontal structure, regional development, and the degree of vertical integration--are also crucial. The authors report that Mexico has undertaken structural reform in the energy sector more slowly than many other countries,but it has introduced changes to attract private investment in natural gas transport and distribution. These changes were a response to the rapid growth in demand for natural gas (about 10 percent a year) in Mexico, which was in turn a response to economic development and the enforcement of environmental regulations. The new regulatory framework provides incentives for firms to invest and operate efficiently and to bear much much of the risk associated with new projects. It also protects captive consumers and improves general economic welfare. The continued vertical integration of the state-owned company Pemex and its statutory monopoly in domestic production posed a challenge to regulators. Their response in liberalizing trade, setting first-hand sales prices, and regulating natural gas distribution makes the Mexican case an interesting example of regulatory design. As the first phase of investment mobilization and competition for the market in Mexican distribution project concludes, remaining challenges include consistently and transparently enforcing regulations, coordinating tasks among government agencies, and ensuring expansion of gas transport services and domestic production. A key challenge in the near term will be fostering competition in the market. In strengthening the role of market forces, one issue is Pemex's discretionary discounts on domestic gas and access to transport services, made possible by its monopoly in domestic production and marketing activities and its overwhelming dominance in transport. The main instrument available to the regulator is proscribing Pemex contract pricing, but more durable and tractable instruments should be considered.Water and Industry,Oil Refining&Gas Industry,Energy and Environment,Oil&Gas,Carbon Policy and Trading

A Unit Commitment and Economic Dispatch Model of the GB Electricity Market – Formulation and Application to Hydro Pumped Storage

We present a well calibrated unit commitment and economic dispatch model of the GB electricity market and applied it to the economic analysis of the four existing hydro pumped storage (PS) stations in GB. We found that with more wind on the system PS arbitrage revenue increases: with every percentage point (p.p) increase in wind capacity the total PS arbitrage profit increases by 0.21 p.p.. However, under a range of wind capacity, the PS’ modelled revenue from price arbitrage is not enough to cover their ongoing fixed costs. Analysing the 2015-18 GB balancing and ancillary services data suggests that PS stations were not active in managing transmission constraints and in fact about 60% of constraint payments went to gas-fired units. However, the PS stations are active in provision of ancillary services such as fast reserve, response and other reserve services with a combined market share of at least 30% in 2018. Stacking up the modelled revenue from price arbitrage with the 2018 balancing and ancillary services revenues against the ongoing fixed costs suggests that the four existing PS stations are profitable. Most of the revenue comes from balancing and ancillary services markets – about 75% – whereas only 25% comes from price arbitrage. However, the revenues will not be enough to cover capex and opex of a new 600 MW PS station. The gap in financing will have to come from balancing and ancillary services market opportunities and less so from purely price arbitrage. Finally, we found that the marginal contribution of most of the existing PS stations to gas and coal plant profitability is negative, while from the system point of view, PS stations do contribute to minimizing the total operating cost

The Effect of Monetary Policy on Commodity Prices: Disentangling the Evidence for Individual Prices

In this paper we study the effect of monetary policy shocks on commodity prices. While most of the literature has found that expansionary shocks have a positive effect on aggregate price indices, we study the effect on individual prices of a sample of four commodities. This set of commodity prices is essential to understand the dynamics of the balance of payments in Colombia. The analysis is based on structural VAR models, we identify monetary policy shocks following [Kim, 1999, 2003] upon quarterly data for commodity prices and their fundamentals for the period 1980q1 to 2010q3. Our results show that commodity prices overshoot their long run equilibrium in response to a contractionary shock in the US monetary policy and, in contrast with literature, the response of the individual prices considered is stronger than what has been found in aggregate indices. Additionally, it is found that the monetary policy explains a substantial share of the fluctuations in prices.Commodity Prices, Monetary Policy, Overshooting. Classification JEL: E31, E52, F42, Q17, Q43.

Energy Storage in Madeira, Portugal: Co-optimizing for Arbitrage, Self-Sufficiency, Peak Shaving and Energy Backup

International audienceEnergy storage applications are explored from a prosumer (consumers with generation) perspective for the island of Madeira in Portugal. These applications could also be relevant to other power networks. We formulate a convex co-optimization problem for performing arbitrage under zero feed-in tariff, increasing self-sufficiency by increasing self-consumption of locally generated renewable energy, provide peak shaving and act as a backup power source during anticipated and scheduled power outages. Using real data from Madeira we perform short and long timescale simulations in order to select end-user contract which maximizes their gains considering storage degradation based on operational cycles. We observe energy storage ramping capability decides peak shaving potential, fast ramping batteries can significantly reduce peak demand charge. The numerical experiment indicates that storage providing backup does not significantly reduce gains performing arbitrage and peak demand shaving. Furthermore, we also use AutoRegressive Moving Average (ARMA) forecasting along with Model Predic-tive Control (MPC) for real-time implementation of the proposed optimization problem in the presence of uncertainty