Demonstrating demand response from water distribution system through pump scheduling

Significant changes in the power generation mix are posing new challenges for the balancing systems of the grid. Many of these challenges are in the secondary electricity grid regulation services and could be met through demand response (DR) services. We explore the opportunities for a water distribution system (WDS) to provide balancing services with demand response through pump scheduling and evaluate the associated benefits. Using a benchmark network and demand response mechanisms available in the UK, these benefits are assessed in terms of reduced green house gas (GHG) emissions from the grid due to the displacement of more polluting power sources and additional revenues for water utilities. The optimal pump scheduling problem is formulated as a mixed-integer optimisation problem and solved using a branch and bound algorithm. This new formulation finds the optimal level of power capacity to commit to the provision of demand response for a range of reserve energy provision and frequency response schemes offered in the UK. For the first time we show that DR from WDS can offer financial benefits to WDS operators while providing response energy to the grid with less greenhouse gas emissions than competing reserve energy technologies. Using a Monte Carlo simulation based on data from 2014, we demonstrate that the cost of providing the storage energy is less than the financial compensation available for the equivalent energy supply. The GHG emissions from the demand response provision from a WDS are also shown to be smaller than those of contemporary competing technologies such as open cycle gas turbines. The demand response services considered vary in their response time and duration as well as commitment requirements. The financial viability of a demand response service committed continuously is shown to be strongly dependent on the utilisation of the pumps and the electricity tariffs used by water utilities. Through the analysis of range of water demand scenarios and financial incentives using real market data, we demonstrate how a WDS can participate in a demand response scheme and generate financial gains and environmental benefits

Bypassing Federalism and the Administrative Law of Negawatts

Presidential unilateralism has become a defining feature of the executive branch. But a related and equally important phenomenon has been largely ignored: federal agency efforts to circumvent statutory federalism boundaries. This move, which the Article calls bypassing federalism, involves using existing jurisdictional authority to work defacto, rather than dejure, reallocations of power. The Article explores agency bypassing through the lens of the Federal Energy Regulatory Commission\u27s ( FERC\u27s ) promotion of demand response in electricity markets. Demand response refers to customer sales of negative watts, or negawatts, back to the electrical grid. FERC, eager to promote demand-side management programs but stymied by the jurisdictional limitations in the Federal Power Act of 1935, recently adopted a strategy that bypasses these federalism boundaries by setting up demand response programs in wholesale markets, which are under its control, to parallel state and local programs. Although the strategy has boosted demand response program participation, the Article ultimately concludes that bypassing is an insalubrious administrative innovation. While it allows agencies to further national objectives without challenging jurisdictional boundaries head on, the strategy has significant downsides. First, statutory constraints may limit an agency\u27s options in a way that results in the promotion of second-best over first-best policies. Second, even de facto jurisdictional adjustments raise federalism questions that we might prefer be addressed through the legislative process. Third, bypassing can be a costly strategy to the extent that it creates animosity between federal agencies and their state counterparts and fails to head off judicial showdowns. Finally, by making a dysfunctional statutory scheme workable, bypassing threatens to delay legislative solutions

Demand response with heat pumps: Practical implementation of three different control options

The electrification of heating and transport and decarbonisation of supply creates a need for demand side flexibility to balance the grid. Heat pumps are expected to form a major part of heat delivery, and many modelling studies have investigated the technical potential of heat pump demand response. However, little empirical work has been reported on the practical implementation of such demand response in occupied homes. This paper presents a cross-case comparison of three early adopters of heat pump demand response in the UK. The aim was to reduce heat pump electricity consumption during the same peak period, but each employed a different control strategy: lowered air temperature setpoints, lowered flow temperature and blocked heat pump compressor. A 56–90% electricity reduction during the peak period was observed; the success of the demand response depended on how the control strategy affected the heat pump and the rest of the heating system. However, no one stakeholder is responsible for all these system components. The fabric, heating distribution and control system and heat pumps installed are highly heterogeneous across the stock, highlighting that flexibility mechanisms must be developed that can be tailored to or work across their range

Demand response behaviour of domestic consumers with photovoltaic systems in the UK: an exploratory analysis of an internet discussion forum

Background: Domestic consumers with photovoltaic (PV) systems in the UK can benefit financially by time-shifting their electricity demand to coincide with the output of the PV. This behaviour is a form of demand response and can provide insights into demand response behaviour more generally. This paper investigates whether people with PV in the UK engage in demand response, what appliances are used, and whether benefitting from free, self-produced electricity appears to influence their behaviour. Methods: To achieve this, the approach presented here consists of an exploratory text analysis of an internet discussion forum frequented by consumers with PV in the UK. Results: Data was gathered on 105 forum participants with PV, of which 45 mentioned engaging in demand response, for example by changing cooking or cleaning practices. Washing machines, dishwashers and electric space and water heaters were the most commonly used appliances for demand response. Six participants engaged in demand response and yet received no direct financial benefit from this behaviour, while 14 participants specifically mentioned the influence of free electricity. Conclusions: The results illustrate novel demand response behaviour compared to previous studies and indicate that while price may be an effective initiator for demand response, there are additional factors beyond price that can enhance responses. The discussion considers the application of these factors to the development of innovative demand tariffs for low-carbon futures

Analysing long-term interactions between demand response and different electricity markets using a stochastic market equilibrium model. ESRI WP585, February 2018

Power systems based on renewable energy sources (RES) are characterised by increasingly distributed, volatile and uncertain supply leading to growing requirements for flexibility. In this paper, we explore the role of demand response (DR) as a source of flexibility that is considered to become increasingly important in future. The majority of research in this context has focussed on the operation of power systems in energy only markets, mostly using deterministic optimisation models. In contrast, we explore the impact of DR on generator investments and profits from different markets, on costs for different consumers from different markets, and on CO2 emissions under consideration of the uncertainties associated with the RES generation. We also analyse the effect of the presence of a feed-in premium (FIP) for RES generation on these impacts. We therefore develop a novel stochastic mixed complementarity model in this paper that considers both operational and investment decisions, that considers interactions between an energy market, a capacity market and a feed-in premium and that takes into account the stochasticity of electricity generation by RES. We use a Benders decomposition algorithm to reduce the computational expenses of the model and apply the model to a case study based on the future Irish power system. We find that DR particularly increases renewable generator profits. While DR may reduce consumer costs from the energy market, these savings may be (over)compensated by increasing costs from the capacity market and the feed-in premium. This result highlights the importance of considering such interactions between different markets

An Overview of Demand Response : From its Origins to the Smart Energy Community

The need to improve power system performance, enhance reliability, and reduce environmental effects, as well as advances in communication infrastructures, have led to demand response (DR) becoming an essential part of smart grid operation. DR can provide power system operators with a range of flexible resources through different schemes. From the operational decision-making viewpoint, in practice, each scheme can affect the system performance differently. Therefore, categorizing different DR schemes based on their potential impacts on the power grid, operational targets, and economic incentives can embed a pragmatic and practical perspective into the selection approach. In order to provide such insights, this paper presents an extensive review of DR programs. A goal-oriented classification based on the type of market, reliability, power flexibility and the participants’ economic motivation is proposed for DR programs. The benefits and barriers based on new classes are presented. Every involved party, including the power system operator and participants, can utilize the proposed classification to select an appropriate plan in the DR-related ancillary service ecosystem. The various enabling technologies and practical strategies for the application of DR schemes in various sectors are reviewed. Following this, changes in the procedure of DR schemes in the smart community concept are studied. Finally, the direction of future research and development in DR is discussed and analyzed.© 2021 IEEE. This work is licensed under a Creative Commons Attribution 4.0 License. For more information, see https://creativecommons.org/licenses/by/4.0/.fi=vertaisarvioitu|en=peerReviewed

Demand side load control in residential buildings with HVAC controller for demand response

Demand Response (DR) is a key factor to increase the efficiency of the power grid and has the potential to facilitate supply-demand balance. Demand side load control can contribute to reduce electricity consumption through DR programs. Especially, Heating, Ventilating and Air Conditioning (HVAC) load is one of the major contributors to peak loads. In the United States, HVAC systems are the largest consumers of electrical energy and a major contributor to peak demand. In this research, the Dynamic Demand Response Controller (DDRC) is proposed to reduce peak load as well as saves electricity cost while maintaining reasonable thermal comfort by controlling HVAC system. To reduce both peak load and energy cost, DDRC controls the set-point temperature in a thermostat depending on real-time price of electricity. Residential buildings are modeled with various internal loads using building energy modeling tools. The weather data in different climate zones are used to demonstrate that DDRC decreases peak loads and brings economic benefit in various locations. In addition, two different types of electricity wholesale markets are used to generate DR signals. To assess the performance of DDRC, the control algorithms are improved to consider the characteristics of building envelopes and HVAC equipment. Also, DDRC is designed to be deployed in various areas with different electricity wholesale markets. The indoor thermal comfort on temperature and humidity are considered based on ASHRAE standard 55. Finally, DDRC is developed to a hardware using embedded system. The hardware of DDRC is based on Advanced RISC Microcontroller (ARM) processor and senses both indoor and outdoor environment with Internet connection capability for DR. In addition, user friendly Graphic User Interface (GUI) is generated to control DDRC.Electrical and Computer Engineerin

Demand response within the energy-for-water-nexus - A review. ESRI WP637, October 2019

A promising tool to achieve more flexibility within power systems is demand re-sponse (DR). End-users in many strands of industry have been subject to research up to now regarding the opportunities for implementing DR programmes. One sector that has received little attention from the literature so far, is wastewater treatment. However, case studies indicate that the potential for wastewater treatment plants to provide DR services might be significant. This review presents and categorises recent modelling approaches for industrial demand response as well as for the wastewater treatment plant operation. Furthermore, the main sources of flexibility from wastewater treatment plants are presented: a potential for variable electricity use in aeration, the time-shifting operation of pumps, the exploitation of built-in redundan-cy in the system and flexibility in the sludge processing. Although case studies con-note the potential for DR from individual WWTPs, no study acknowledges the en-dogeneity of energy prices which arises from a large-scale utilisation of DR. There-fore, an integrated energy systems approach is required to quantify system and market effects effectively