Optimizing Energy Storage Participation in Emerging Power Markets

The growing amount of intermittent renewables in power generation creates challenges for real-time matching of supply and demand in the power grid. Emerging ancillary power markets provide new incentives to consumers (e.g., electrical vehicles, data centers, and others) to perform demand response to help stabilize the electricity grid. A promising class of potential demand response providers includes energy storage systems (ESSs). This paper evaluates the benefits of using various types of novel ESS technologies for a variety of emerging smart grid demand response programs, such as regulation services reserves (RSRs), contingency reserves, and peak shaving. We model, formulate and solve optimization problems to maximize the net profit of ESSs in providing each demand response. Our solution selects the optimal power and energy capacities of the ESS, determines the optimal reserve value to provide as well as the ESS real-time operational policy for program participation. Our results highlight that applying ultra-capacitors and flywheels in RSR has the potential to be up to 30 times more profitable than using common battery technologies such as LI and LA batteries for peak shaving.Comment: The full (longer and extended) version of the paper accepted in IGSC 201

Auction Basics for Wholesale Power Markets: Objectives and Pricing Rules

Power systems have distinctive features that greatly complicate the development of auction designs. This study reviews the theory and practice of auction design as it relates specifically to U.S. restructured wholesale power markets, i.e., centrally-administered wholesale power markets with congestion managed by locational marginal prices. Basic auction concepts such as reservation value, net seller surplus, net buyer surplus, competitive market clearing, market efficiency, market pricing rules, supply offers, demand bids, strategic capacity withholding, and market power are explained and illustrated. Complicating factors specific to wholesale power markets are clarified, and recent advances in computational tools designed to address these complications are briefly noted.market power; Auction markets; power systems; design; efficency; pricing rules; agent-based test beds

Optimizing energy storage participation in emerging power markets

The growing amount of intermittent renewables in power generation creates challenges for real-time matching of supply and demand in the power grid. Emerging ancillary power markets provide new incentives to consumers (e.g., electrical vehicles, data centers, and others) to perform demand response to help stabilize the electricity grid. A promising class of potential demand response providers includes energy storage systems (ESSs). This paper evaluates the benefits of using various types of novel ESS technologies for a variety of emerging smart grid demand response programs, such as regulation services reserves (RSRs), contingency reserves, and peak shaving. We model, formulate and solve optimization problems to maximize the net profit of ESSs in providing each demand response. Our solution selects the optimal power and energy capacities of the ESS, determines the optimal reserve value to provide as well as the ESS real-time operational policy for program participation. Our results highlight that applying ultra-capacitors and flywheels in RSR has the potential to be up to 30 times more profitable than using common battery technologies such as LI and LA batteries for peak shaving

ALTERNATIVE AUCTION INSTITUTIONS FOR ELECTRIC POWER MARKETS

Restructuring of electric power markets is proceeding across the United States and in many other nations around the world. The performance of these markets will influence everything from the prices faced by consumers to the reliability of the systems. The challenges of these changes present many important areas for research. For much of the northeastern United States, restructuring proposals include, at least for the short term, the formation of a single-sided auction mechanism for the wholesale market. This research uses experimental methods to analyze how these markets may function. In the experiments, the two basic uniform price auction rules are tested under three different market sizes. Early experimental results suggest the commonly proposed last-accepted-offer auction works well, but market power could be a real concern.Resource /Energy Economics and Policy,

Multifractal analysis of Power Markets. Some empirical evidence

This work is intended to offer a comparative analysis of the statistical properties of hourly prices in the day–ahead electricity markets of several countries. Starting from the intermittent nature of typical price fluctuations in many power markets, we will provide evidence that working into a stochastic multifractal analysis framework can be of help to asses typical features of day–ahead market prices.Multifractals, Hurst Coefficient, Power Markets

Spot price dynamics in deregulated power markets

Modelling spot price behavior plays a key role in the electric- ity market, since this is the breeding engine for the activity in the corre- sponding forward and futures market: developers and generators (as well as traders) need to know how electricity prices behave, as their profitabil- ity depends on them. Additionally, credit rating agencies need to monitor the exposure of different players in the market to price fluctuations and risks. Starting from those considerations, this work is intended to offer a comparative analysis of the statistical properties of hourly prices in the day–ahead electricity markets of several countries, in order to fix some features which a good model should have to fit day–ahead prices. A number of stochastic processes will be then examined as perspective candidate to generate sample paths with explanatory power respect on the real time–series, and results will be discussed.spot prices, self–affinity, Hurst exponent.

A pricing measure to explain the risk premium in power markets

In electricity markets, it is sensible to use a two-factor model with mean reversion for spot prices. One of the factors is an Ornstein-Uhlenbeck (OU) process driven by a Brownian motion and accounts for the small variations. The other factor is an OU process driven by a pure jump L\'evy process and models the characteristic spikes observed in such markets. When it comes to pricing, a popular choice of pricing measure is given by the Esscher transform that preserves the probabilistic structure of the driving L\'evy processes, while changing the levels of mean reversion. Using this choice one can generate stochastic risk premiums (in geometric spot models) but with (deterministically) changing sign. In this paper we introduce a pricing change of measure, which is an extension of the Esscher transform. With this new change of measure we also can slow down the speed of mean reversion and generate stochastic risk premiums with stochastic non constant sign, even in arithmetic spot models. In particular, we can generate risk profiles with positive values in the short end of the forward curve and negative values in the long end. Finally, our pricing measure allows us to have a stationary spot dynamics while still having randomly fluctuating forward prices for contracts far from maturity.Comment: 37 pages, 7 figure

Integrating independent power producers into emerging wholesale power markets

Many developing and industrial countries have sought to open their electricity industries to competition. In both contexts, policymakers and investors have to deal with the consequences of earlier, more partial sector liberalization measures. Foremost among these is the existence of long-term contracts with independent power producers (IPPs). The long-term nature of these contracts has complicated the introduction of more far-reaching sectoral reform designed to harness competitive market forces for the benefit of consumers. In developing countries, introducing competition is often coupled with breaking up and privatizing state-owned electricity monopolies. In this context, discussion of renegotiation of power purchase agreements has tended toward the polemical. At one end are those who resist any change, arguing that the"sanctity of contracts"precludes modification of contract terms. At the other end are those who favor governments taking coercive measures to modify existing contracts in the name of maximizing economic welfare and minimizing the burden of sector reform on consumers and on the state. Drawing on recent country experiences, the authors analyze alternative approaches to restructuring contracts and designing power markets to reduce rigidities and incentivize IPPs to participate more fully in wholesale power markets and to take on greater market risk. The authors conclude that forced market integration or forced contract negotiation have failed and are counterproductive. Conversely, in countries where IPPs provide a sizable proportion of generation capacity, ignoring market integration may result in insufficient market liquidity and discourage new entry, attenuating the scope for market forces to act for the benefit of consumers. Failure to adapt power purchase contracts and market rules imposes huge resource costs on the economy beyond the financial obligations consumers and taxpayers must bear. Based on recent experience, a combination of measures, including adaptation of specific market rules, contractual alternatives for enhancing market liquidity, contract buyout provisions, transitional financing mechanisms, and characteristics of the successor entity to the power purchaser, offer promising approaches for reconciling preexisting IPP contracts with new market structures and reducing the magnitude of above-market costs associated with such contracts.Markets and Market Access,Payment Systems&Infrastructure,General Technology,Labor Policies,Banks&Banking Reform,Markets and Market Access,Access to Markets,Banks&Banking Reform,Economic Theory&Research,General Technology

Revisiting the Merit-Order Effect of Renewable Energy Sources

An on-going debate in the energy economics and power market community has raised the question if energy-only power markets are increasingly failing due to growing feed-in shares from subsidized renewable energy sources (RES). The short answer to this is: No, they are not failing. Energy-based power markets are, however, facing several market distortions, namely from the gap between the electricity volume traded at day-ahead markets versus the overall electricity consumption as well as the (wrong) regulatory assumption that variable RES generation, i.e., wind and photovoltaic (PV), truly have zero marginal operation costs. In this paper we show that both effects over-amplify the well-known merit-order effect of RES power feed-in beyond a level that is explainable by underlying physical realities, i.e., thermal power plants being willing to accept negative electricity prices to be able to stay online due to considerations of wear & tear and start-stop constraints. We analyze the impacts of wind and PV power feed-in on the day-ahead market for a region that is already today experiencing significant feed-in tariff (FIT)-subsidized RES power feed-in, the EPEX German-Austrian market zone ($\approx\,$20% FIT share). Our analysis shows that, if the necessary regulatory adaptations are taken, i.e., increasing the day-ahead market's share of overall load demand and using the true marginal costs of RES units in the merit-order, energy-based power markets can remain functional despite high RES power feed-in.Comment: Working Paper (9 pages, 11 figures, 5 tables) - Some revisions since last version (10 February 2014). (Under 2nd review for IEEE Transactions on Power Systems