Battery Investment Research Articles

Power to the people: Evolutionary market pressures from residential PV battery investments in Australia

Falling costs of solar PV and battery technologies are continuously changing the customer relationship with their electricity network. By managing their own self-generation, customers are able to place natural selection pressure on utilities to evolve. The devised techno-economic simulation model projects residential PV and battery investment decisions over 20 years in Perth, Australia to quantify the potential market impacts from policy and customer investment conditions. Using real-world demand and insolation profiles from 261 households, this research evaluates how cumulative customer PV and battery investments changes the network and market operating conditions, while under the influence of various feed-in tariff values. The results indicate that high feed-in tariff policy costs in the short-term, make it economically challenging to prevent or restrain significant residential PV-battery adoption in the longer-term. Moreover, continuous increases in residential PV-battery system installations eventually lead to annual net-exports substantially exceeding net-imports on the distribution network. This significant shift in network operation provides an opportunity for policymakers to utilise behind-the-meter PV-battery investments and decentralised energy markets to meet wider renewable energy and decarbonisation goals.

Can applying renewable energy for Australian sugarcane irrigation reduce energy cost and environmental impacts? A case study approach

Abstract In Australian sugarcane production, 90% of irrigation pumps are connected to the national electricity grid. In regional Queensland, where irrigated sugarcane is grown, both the retailer and distribution network service providers are government owned and highly regulated. This study investigates options for on-farm embedded generation from a range of commercially available components, to reduce energy costs of furrow, centre pivot, and Big Gun® irrigation. This study confirms that demand-side management crucially affects the economic feasibility of embedded generation. Connection rules, such as feed-in tariffs and export limits affecting renewable embedded generation can also influence emissions abatement costs and investment returns. When export limits are allowed on larger sites (solar PV systems >40 kW), abatement costs fall from $109/t CO2e to $18/t CO2e and the present value of the investment improves substantially. The analysis reveals economically feasible opportunities exist for small-scale solar PV system installations (under 40 kW), reducing NPC of pumping from 12 to 25% and emission reductions ranging from 1245 t CO2e to 1314 t CO2e per installation over 25 years. Where a site is not eligible for a feed-in tariff, high renewable energy utilisation rates are required to make the site feasible. Batteries did not feature as an optimal component, even when battery storage and replacement values were discounted by 60%, indicating that seasonal load profiles under-use a battery investment. Therefore, batteries are inefficient and can be avoided in an irrigation microgrid.

Optimal battery purchasing and charging strategy at electric vehicle battery swap stations

A battery swap station (BSS) is a facility where electric vehicle owners can quickly exchange their depleted battery for a fully-charged one. In order for battery swap to be economically sound, the BSS operator must make a long-term decision on the number of charging bays in the facility, a medium-term decision on the number of batteries in the system, and short-term decisions on when and how many batteries to recharge. In this paper, we introduce a periodic fluid model to describe charging operations at a BSS facing time-varying demand for battery swap and time-varying prices for charging empty batteries, with the objective of finding an optimal battery purchasing and charging policy that best trades off battery investment cost and operating cost including charging cost and cost of customer waiting. We consider a two-stage optimization problem: An optimal amount of battery fluid is identified in the first stage. In the second stage, an optimal charging rule is determined by solving a continuous-time optimal control problem. We characterize the optimal charging policy via Pontryagin’s maximum principle and derive an explicit upper bound for the optimal amount of battery fluid which allows us to quantify the joint effect of demand patterns and electricity prices on battery investment decisions. In particular, fewer batteries are needed when the peaks and the troughs of these periodic functions occur at different times.

Two-stage energy generation schedule market rolling optimisation of highly wind power penetrated microgrids

Considering increasingly scale of renewable energy resources penetration in modern power system, especially the wind power generation, this paper constructs a joint operation system which combined the wind turbine with the battery energy storage system (BESS) in a highly wind power penetrated microgrid, in order to weaken the impact of wind power uncertainty. Simultaneously, the demand response (DR) is optimally incorporated into system operation as flexible resources to adjust the imbalance of supply-demand in the microgrid. The battery investment capital and operation maintenance cost are also modeled as components of the optimisation. A novel two-stage energy generation schedule market rolling optimisation framework, which consists of the day-ahead energy generation schedule market and intraday energy generation reschedule market, is presented to pursue the best energy profits for the microgrid. A mutation-based artificial bee colony (MABC) algorithm is designed for the day-ahead market optimisation due to the nonlinear of battery operation model in this stage, while without considering the dispatch of battery, the intraday market rolling optimisation is solved as a mixed integer programming. Simulations are carried out on a small-scale microgrid with high penetration of wind power, the results show that the constructed joint operation system can effectively reduce the effect of wind power uncertainty and the proposed two-stage energy generation schedule market rolling optimisation framework can adjust the generation schedule along with the updated wind power predicted data, and thus increase the total energy profits for the joint operation system prominently.

Including power management strategies and load profiles in the mathematical optimization of energy storage sizing for fuel consumption reduction in maritime vessels

Abstract Choosing the optimal type and size of energy storage for a given hybrid maritime vessels is challenging. Investment cost, fuel saving and energy storage expected life time will be affected by the choices. Furthermore, the optimum choices depend on the operation profile of the vessel as well as safety related constraints in different vessel mode of operations. In addition, the optimum power management strategy will be mode dependent as well as dependent on the type and size of onboard energy storage. Finally, the total system has to fulfill certain safety related rules and regulations that typically both favour the use of storage and set some constraints to the size and the utilization of the storage. In this paper we propose a mathematical optimisation model called OBLIVION that stands for “Optimised Battery Lifetime In Vessels Internal Operations and Networks”. OBLIVION is created to support battery investment decisions. Beyond including battery degradation and desired battery lifetime in the choice, the model facilitates analysis of how the investment decisions change for different combinations of vessel operation modes. The key contribution of this paper is the proposed methodology to formulate technical and safety constraints, represent different vessel modes of operation and battery storage degradation in a way suitable for inclusion within mathematical optimisation models. Moreover, analyses that demonstrate how these features affect the storage investment decisions are presented. Mathematical formulations of constraints such as closed and open bus-tie breaker operation, true spinning reserve requirements as well as spinning reserve provided by batteries are included as well.

A simulation framework for the dynamic assessment of energy policy impacts on customer PV-battery adoption and associated energy market impacts

As energy systems undergo significant utility-scale transitions to combat global warming, the capacity for future customers to lead the next transition needs to be studied and quantified. This research presents a customer-driven energy policy simulation framework that integrates endogenous customer PV and battery investment, the energy market and generators, with the means to comparatively evaluate market evolution and policy impacts. Energy policies can also be designed and tested within this framework to assess the potential for customer-driven renewable energy transition pathways. A hypothetical analysis is presented.

Analysis of solar and battery requirements for hybrid DC/AC powered households in the USA

US households consume more electricity compared to other developed countries due to the fact that majority of the US household loads are inefficient. As a result, deployment of residential solar PV cost is increased given the high-power consumption and becomes less viable. Utilities are also increasingly applying surcharges to customers with solar PV installations because of direct impacts to the grid, making purely solar PV installations unattractive. This is especially in the case for low-income households, where they are seemingly shut out from participating in the energy economy given the penalties and the costs. This research primary focus is to make Installed Cost Benchmarks for Residential Solar Photovoltaic with Energy Storage costs more affordable for an average-income home owner in the USA; one approach is to reduce power consumption within the household by adapting DC appliances. So, a compelling means towards reducing household load is to convert a portion of household electrical loads such as LED lighting, air conditioning, ceiling fans, and electronic loads to DC. Secondly, optimizing size of solar panels and battery and without the need for energy export, it compensates for surcharges and recover return on solar investment. Data provided in this paper gives an insight into adapting suitable hybrid DC/AC architecture for three different types of households associated with five different geographical regions based of different climactic conditions spread across the USA. The systems are distinguished by the degree to which redundant AC to DC conversion stages are reduced, which will be inversely proportional to cost. This paper shows that deployment of DC distribution within the house will result in lower average cost and better returns on solar and battery investment than revealed by the NREL study. Also, outlines the costs and savings of different architecture that can be adaptable based on the type of the house, location, savings, and affordability. Only this paper shows the benefits occur due to the reduced number of solar panels and battery storage required when compared to conventional AC powered households. The end goal of this work is to increase the adoptability of solar PV across a more diverse population with a particular focus on low-income households.

The coming disruption: The movement towards the customer renewable energy transition

The technical and financial influences that shape customer investment in behind-the-meter PV and battery systems, provide the means to forecast and quantify customer energy transitions. By utilising techno-economic scenario analysis, this research assists policymakers to understand the impacts of their decisions on future energy market relationships between the customer and utilities. Two case studies are presented, firstly to evaluate the influence of annual increases in usage charges, and secondly the level of feed-in tariff compensation on customer PV and battery investment over a 15-year forecast period located in Perth, Australia. The findings indicate that even without annual increases in usage charges, the falling installation costs of PV and battery technologies will make customer PV-battery systems financially viable within the 15-year forecast period. Additionally, the removal of the feed-in tariff leads to greater reductions in eventual grid consumption. By the end of the forecast period, customer PV-battery systems with the highest financial performance are able to reduce grid consumption above 90% resulting in significant energy resources being transferred out of the energy market. This necessitates the market integration of customer energy resources and provides an opportunity to leverage a combination of customer and utility energy resources for the renewable energy transition.

The reuse of electrified vehicle batteries as a means of integrating renewable energy into the European electricity grid: A policy and market analysis

The financial sense of reused automotive battery systems providing stationary energy storage is investigated in the paper. A comprehensive review of existing used batteries projects is presented, followed by an evaluation of individual European countries regulations and electricity market conditions. The authors performed detailed simulations of the Net Present Value of four battery system investments: residential solar panel + battery or battery-only, commercial/industrial level solar panel + battery and primary reserve battery investment. The combination of electricity prices and Feed in Tariff schemes can either act as an enabler or a barrier to the economics of battery investment. At the moment, the investment in used batteries makes sense mostly in Germany but countries such as UK and Italy or Spain could be future candidates. In terms of energy policy adjustments, appropriate financial incentives are necessary to encourage the investment in such systems. Most importantly, energy policy in EU should incentivise the use of 2nd hand automotive batteries for stationary applications.

Economic assessment of residential PV systems with self-consumption and storage in Portugal

A progressive implementation of renewable microgeneration, mainly small sized Photovoltaics, in low voltage distribution networks is ongoing. In this context, self-consumption with storage allows to highlight the prosumer concept, bearing in mind that this strategy may be interesting both from a technical and economical perspectives. The intelligent network environment or Smart Grid comes close to this new model and may have a critical relevance in the management of intelligent power distribution networks, in the framework of a Smart Environment. This paper intends to give an additional contribution on the subject by investigating the economic profitability of different residential PV systems configurations. These include traditional “injects all into the network/consumes all from the network”, self-consumption, storage and net-metering. The joint operation of self-consumption and battery storage is particularly focused as it presents the current trend in residential PV systems. The results of the performed economic analysis point to the conclusion that self-consumption is already attractive, but storage is not a profitable solution, because battery investment is still too high, despite the cost reduction witnessed in recent years.

Energy Storage Sizing for Rooftop Grid-Connected PV System

This paper investigates the optimum dimensioning of a battery energy storage in a grid-connected PV system. An energy flow decision program of the system was developed, in the MATLAB to minimize the operatingcost of the system. Optimizing the energy flow schedule was performed under two different energy flow control strategies: 1) The battery energy has been released to the grid, during the daytime, only up to a predefined value of the state of charge in case A. 2) The battery is allowed to discharge its energy on peak hours, even up to the minimum charge state in case B. Comparing both cases in one for one tariff scheme, case A was much beneficial to adopt, while case B generated higher financial benefits compared to case A, when incentives were given in feed-in tariff or for the battery investment cost. With one for one tariff scheme, the PV system without the battery energy storage was much more beneficial to adopt from the financial point of view, but not from the operational point of view.

How low exergy buildings and distributed electricity storage can contribute to flexibility within the demand side

Residential buildings are responsible for a substantial and steadily growing share of the global electricity consumption, approximately 30%. The ability to control the timing and magnitude of the aggregate electricity consumption of buildings is acquiring critical relevance. Buildings play a pivotal role in defining the shape and composition of the final electricity demand, and have an impact on the existing and projected electrical system infrastructure. This paper proposes distributed electrical storage using electrical batteries at the residential level, as an economical and technically feasible way to introduce a degree of responsiveness with the demand of residential buildings without compromising the comfort of users.The objective of the paper is to devise the operative principles governing the relation between the grid operator and a community of low exergy (lowEx) buildings, under the assumption that the grid operator is interested in controlling the form of the aggregate electricity consumption in that community.This paper presents a pricing policy aimed to stimulate a power-aware consumption, and consequently peak-shave the total electricity profile. The introduced pricing scheme separately addresses energy and power, and provides an incentive for buildings to invest in decentralized generation and storage technologies. The paper presents a methodology to determine the optimal amount of decentralized electrical storage and PV necessary to meet the objectives of the grid operator and allowing users to obtain a profit from the dynamic electricity tariff.A model is used to determine the optimal battery and PV investment from the perspective of the user. The analyses show that the introduced electricity tariff triggers an equilibrium, in which users invest between 20% and 25% of the total incurred cost in battery and PV.The PV and the battery input power were found to be mainly related to the objective of reducing the energy cost. On the other hand, the battery capacity and output power were found to be associated with the peak reduction objective. Users invest less than 10% of the total battery investment share in the battery input power. This fact indicates that contrary to a battery usage driven by the price volatility, which is proposed in many models, the battery is mainly used as power-to-energy buffer. Energy is slowly stored in the battery and rapidly released at critical peak hours.

Sizing Study of Second Life Li-ion Batteries for Enhancing Renewable Energy Grid Integration

Renewable power plants must comply with certain codes and requirements to be connected to the grid, being the ramp-rate compliance one of the most challenging requirements, especially for photovoltaic or wind energy generation plants. Battery-based energy storage systems represent a promising solution due to the fast dynamics of electrochemical storage systems, besides their scalability and flexibility. However, large-scale battery energy storage systems are still too expensive to be a mass market solution for the renewable energy resources integration. Thus, in order to make battery investment economically viable, the use of second life batteries is investigated in the paper. This paper proposes a method to determine the optimal sizing of a second life battery energy storage system (SLBESS). SLBESS performance is also validated and, as an ultimate step, the power exchanged with the batteries is calculated during one-year operation. The power profile obtained is further used to define the cycling patterns for laboratory testing of second life batteries and to study their ageing evolution when used for the power smoothing renewable integration application. Real photovoltaic energy generation data from a Spanish plant were used for the study.

Energy Cost Minimization for Distributed Internet Data Centers in Smart Microgrids Considering Power Outages

In this paper, we investigate the problem of minimizing energy cost for distributed Internet data centers (IDCs) in smart microgrids while taking system dynamics into consideration. Specifically, IDC operators expect to minimize the long-term energy cost with the uncertainties in electricity price, workload, renewable energy generation, and power outage state. At first, we formulate the problem as a stochastic program that captures service request distribution, server provisioning, energy storage management, generator scheduling, power transactions between smart microgrids, and main grids. Second, we use the Lyapunov optimization technique to design an operation algorithm, which enables an explicit tradeoff between energy cost saving and battery investment cost. Finally, the effectiveness of the proposed algorithm is evaluated with practical data.