Deployment Of Array Research Articles

Study of correlations between seismic data and Virgo’s gravitational-wave detector data

It is expected that noise produced by terrestrial gravity fluctuations will start to limit the sensitivity of the ground-based, gravitational-wave detector Virgo in coming observation runs. A system is under preparation at Virgo to cancel this noise, also known as Newtonian noise. This Newtonian noise cancelation system requires the deployment of seismometer arrays inside the Virgo buildings. Crucial for the design of such a system is a detailed understanding of correlations between ground vibrations and Virgo’s gravitational waves detector data. In this article, we present first analyses of such correlations observed with a tiltmeter. We find that revealed correlations are stronger than predicted by possible pure gravitational coupling, which is pointing towards additional coupling mechanisms. These findings might impact the design of the Newtonian noise cancelation system if the additional couplings cannot be mitigated.

Acoustic Wave Focusing From Reconfigurable Acoustic Arrays Based on a Bricard-Miura Synthesis

Abstract Recent studies have shown that reconfigurable acoustic arrays inspired from rigid origami structures can be used to radiate and focus acoustic waves. Yet, there is a need for exploration of single-degree-of-freedom deployment to be integrated with such arrays for sake of tailoring wave focusing. This research explores a reconfigurable acoustic array inspired from a regular Miura-ori unit cell and threefold-symmetric Bricard linkage. The system focuses on acoustic waves and has single-degree-of-freedom motion when incorporated with a modified threefold-symmetric Bricard linkage. Three configurations of the array are analyzed where array facets that converge towards the center axis are considered to vibrate like baffled pistons and generate acoustic waves into the surrounding fluid. An analytical model is constructed to explore the near-field acoustic focusing behavior of the proposed acoustic array. The wave focusing capabilities of the array are verified through proof-of-principle experiments. The results show that the wave focusing of the array is influenced by the geometric parameters of the facets and the relative distance of facets to the center axis, in agreement with simplified ray acoustics estimates. These findings underscore the fundamental relationship between focusing sound radiators and geometric acoustics principles. The results encourage broader exploration of acoustic array designs inspired from integrated single-degree-of-freedom linkages and origami structures for sake of straightforward array deployment and reconfiguration.

Ambient Infrasound Noise, Station Performance, and Their Relation to Land Cover across Alaska

AbstractThe addition of 108 infrasound sensors—a legacy of the temporary USArray Transportable Array (TA) deployment—to the Alaska regional network provides an unprecedented opportunity to quantify the effects of a diverse set of site conditions on ambient infrasound noise levels. TA station locations were not chosen to optimize infrasound performance, and consequently span a dramatic range of land cover types, from temperate rain forest to exposed tundra. In this study, we compute power spectral densities for 2020 data and compile new ambient infrasound low- and high-noise models for the region. In addition, we compare time series of root-mean-squared (rms) amplitudes with wind data and high-resolution land cover data to derive noise–wind speed relationships for several land cover categories. We observe that noise levels for the network are dominated by wind, and that network noise is generally higher in the winter months when storms are more frequent and the microbarom is more pronounced. Wind direction also exerts control on noise levels, likely as a result of infrasound ports being systematically located on the east side of the station huts. We find that rms amplitudes correlate with site land cover type, and that knowledge of both land cover type and wind speed can help predict infrasound noise levels. Our results show that land cover data can be used to inform infrasound station site selection, and that wind–noise models that incorporate station land cover type are useful tools for understanding general station noise performance.

Dynamics and control of spacecraft solar array deployment considering physical contacts between locking mechanisms

The numerical simulation of the deployment and locking process of flexible appendages is an important topic in the overall design of spacecraft. In the existing research, the connecting mechanism between the solar panels is usually regarded as an ideal revolute constraint, and the locking process is simulated by applying a virtual lock torque related to the deployment angle. However, this method cannot obtain the physical contact force history, and because the physical meaning of the stiffness term in the lock torque function is not clear, it is difficult to accurately illustrate the frequency characteristics of the flexural vibration of the panels in the post-lock phase. In fact, the locking process is a frequent contact-impact process between the lock pin and groove. In this study, a typical deployable spacecraft with torsion-spring-driven panels were investigated numerically. The locking mechanism is modeled as a physical entity, and the continuous contact force model between the lock pin and groove is established. The contact stiffness of cylindrical line-contact is given by preloading calculation using the finite element method. Based on the multibody dynamics, rigid body model and flexible body model of the solar panels are established respectively. Through the comparison between the numerical simulation results of the two models, it is found that the rigid body model will produce excessive contact force and false high-frequency vibration. Furthermore, the attitude PD controller of spacecraft is designed, and the difference of system dynamic response in the deployment process under the main-body free state and the main-body controlled state is studied. The vibration frequency under the main-body controlled state is close to the first-order natural frequency of the structural finite element analysis, which verifies the rationality of the calculation results of the model.

Hydrodynamic characteristics of a hybrid oscillating water column-oscillating buoy wave energy converter integrated into a π-type floating breakwater

Combining multiple-types of Wave Energy Converters (WECs) and integrating them into in-development or pre-existing marine platforms can reduce the total Levelised Cost of Energy (LCoE) by sharing infrastructures and maintenance costs. The current study proposes an innovative multi-purpose solution by deploying an Oscillating Buoy (OB) device inside the chamber of an Oscillating Water Column (OWC) WEC integrated into a π-type floating breakwater. A fully non-linear time-domain model based on the Higher-Oder Boundary Element Method (HOBEM) is established to investigate the hydrodynamic performance of the proposed concept. The non-linear time-domain model is generalised to incorporate the OWC (aero and hydrodynamics coupling) and multi-body interaction. A series of simulations are performed to examine the hydrodynamic performance of the proposed hybrid concept. Results were compared with an isolated breakwater and an OWC-integrated breakwater, demonstrating that the proposed hybrid concept has a beneficial impact on both wave energy conversion and transmitted wave attenuation. In addition, long-period waves enter into the chamber more easily, which leads to a larger inner water motion and pressure fluctuation in the chamber. Importantly, there exists a coupled resonant motion between the OB device and the water surface in the chamber, which enhances the maximum capture efficiency and the efficiency frequency bandwidth. The asymmetric OB with a triangle-shaped bottom is found to absorb the wave energy along with the water depth more effectively. Despite the better performance, the current design does not increase the characteristic system volume and has no external moving part, making it ideal for array deployment.

The use of 6DOF measurement in volcano seismology – A first application to Stromboli volcano

Volcano seismology, while its value for surveillance of an active volcano is undebatable, is a very demanding field when it comes to station deployment, maintenance, and finally interpreting the measurements. Most valuable in the past was the deployment of arrays of sensors to evaluate the properties of the entire wavefield in order to classify, locate, and estimate the dominant mechanism of the corresponding sources. While very beneficial, an array of seismographs is very hard to maintain in a permanent installation at an active volcano. With the advent of new instrumentation based on fiber optic technology such as Distributed Acoustic Sensing (DAS) with fiber optic cables as well as Fiber-Optic Gyroscopes (FOG) the measurement of deformation and rotation, i.e., the gradient of the wavefield is feasible. The advantage of the FOG instrumentation with respect to DAS lies in the portability and ease of deployment, which is very similar to standard deployments of traditional seismometers. During a field campaign in summer 2018 we were able to install three FOGs together with classical broadband seismometers in close proximity to the active vents of Stromboli volcano (Italy). We show that with this new six-degrees-of-freedom (6DOF) measurement we are able to analyze the wavefield composition, a property normally reserved for array(s) of seismic sensors. As a first result, we can support earlier array-derived findings that a large portion of the wavefield at Stromboli volcano is formed by SV- and SH- type waves. We also present first locations of these signals facilitating the polarization properties of the combined measurement of gyroscopes and seismometers. They emphasize the benefit of recording wavefield gradients. In addition to these array-like results, the 6DOF recordings show a clear separation of at least three distinct groups of volcanic events of which two are already known and one represents a jetting event that appears nearly invisible for classical seismometers. However, rotational motions - or more general - gradients of the wavefield experience severe distortions by local velocity fluctuations and topography significantly complicating the application of 6DOF techniques at activate volcanoes.

Folding and deploying identical thick panels with spring-loaded hinges

Many large deployable flat rigid arrays for aerospace applications, e.g., solar panels and reflectarray antennas, are preferably made from identical panels. It is challenging to pack them into a compact bundle before launching and deploy to a flat surface once in the orbit, especially if they are having bi-directional deployments. In this paper, we propose a folding scheme based on the Hamiltonian circuit that can successfully fold a chessboard-like array into a compact package with two stacks of panels without any voids. Since this approach leads to a multiple degrees-of-freedom (DoFs) assembly kinematically, simple spring-loaded hinges are used to synchronise the deployment. An effective optimisation method is subsequently proposed to select the stiffness of rotational joints to ensure a collision-free deployment. Dynamic simulation of the deployment and a collision detection method are incorporated into the optimisation process. By this approach, the trajectories of panels are sequenced to avoid collisions during the deployment, and the array always deploys to a flat surface from packaged stacks. Both the folding schemes and subsequent deployments were validated successfully by experiments. Though we consider only rectangular panels here, the approach can be extended to deployable arrays of any regular shape.

Investigating Selectorless Property within Niobium Devices for Storage Applications.

Resistive random-access memory (RRAM) crossbar arrays have shown significant promise as drivers of neuromorphic computing, in-memory computing, and high-density storage-class memory applications. However, leakage current through parasitic sneak paths is one of the dominant obstacles for large-scale commercial deployment of RRAM arrays. To overcome this issue without compromising on the structural simplicity, the use of inherent selectors native to switching is one of the most promising ways to reduce sneak path currents without sacrificing density associated with the simple two-electrode structure. In this study, niobium oxide (NbOx) was chosen as the resistive switching layer since it co-exhibits non-volatile memory and metal-insulator-transition selector behavior. Experimental results demonstrate abnormal phenomena in the reset process: a rapid decrease in current, followed by an increase when reset from the on state. The current conduction mechanism was examined through statistical analysis, and a conduction filament physical model was developed to explain the abnormal phenomenon. Under optimized operation conditions, non-linearity of ∼500 and fast switching speeds of 30 ns set and 50 ns reset were obtained. The switching behaviors with the intrinsic selector property make the NbOx device an attractive candidate for future memory and in-memory computing applications.

Millimeter-Wave Power Amplifier ICs for High Dynamic Range Signals

The next-generation 5G and beyond- 5G wireless systems have stimulated a substantial growth in research, development, and deployment of mm-Wave electronic systems and antenna arrays at various scales. It is also envisioned that large dynamic range modulation signals with high spectral efficiency will be ubiquitously employed in future communication and sensing systems. As the interface between the antennas and transceiver electronics, power amplifiers (PAs) typically govern the output power, energy efficiency, and reliability of the entire wireless systems. However, the wide use of high dynamic range signals at mm- Wave carrier frequencies substantially complicates the design of PAs and demands an ultimate balance of energy efficiency and linearity as well as other PA performances. In this review paper, we will first introduce the system-level requirements and design challenges on mm-Waves PAs due to high dynamic range signals. We will review advanced active load modulation architectures for mm-Wave PAs and power devices. We will then introduce recent advances in mm-Wave PA technologies and innovations with several design examples. Special design considerations on mm-Wave PAs for phased array MIMOs and high mm-Wave frequencies will be outlined. We will also share our vision on future technology trends and innovation opportunities.

Irregular microphone array design for broadband beamforming

Sparse microphone array design is receiving a great deal of attention, largely due to the capacity to reduce the number of microphones. However, in general, using a sparse array for broadband beamforming still requires a large number of microphones for a complex/higher-order beam pattern, while a sparse array deployment is normally designed for a specific beam pattern. This paper aims to design a versatile sparse microphone array that can be used for different beam patterns. Furthermore, we aim to reduce the number of microphones in the sparse array while ensuring that its performance can continue to compete with a highly dense and uniform array in terms of broadband beamforming. An irregular microphone array in a planar surface with the maximum number of different distances between the microphones is proposed. It is demonstrated that the irregular microphone array is well-suited to the sparse recovery algorithms that are used to reconstruct the sound sources. From the reconstructed sound sources, an array interpolation method is presented to obtain an interpolated dense and uniform microphone array that performs well with broadband beamforming. This manuscript covers the theoretical background of the method as well as the experimental results.

Accuracy Versus Complexity for mmWave Ray-Tracing: A Full Stack Perspective

The millimeter wave (mmWave) band will provide multi-gigabits-per-second connectivity in the radio access of future wireless systems. The high propagation loss in this portion of the spectrum calls for the deployment of large antenna arrays to compensate for the loss through high directional gain, thus introducing the need for a spatial dimension in the channel model to accurately represent the performance of a mmWave network. In this perspective, ray tracing can characterize the channel in terms of Multi Path Components (MPCs) to provide a highly accurate model, at the price of extreme computational complexity (e.g., for processing detailed environment information about the propagation), which may limit the scalability of the simulations. In this paper, we present possible simplifications to improve the trade-off between accuracy and complexity in ray-tracing simulations at mmWaves by reducing the total number of MPCs. The effect of such simplifications is evaluated from a full-stack perspective through end-to-end simulations, testing different configuration parameters, propagation scenarios, and higher-layer protocol implementations. We then provide guidelines on the optimal degree of simplification, for which it is possible to reduce the complexity of simulations with a minimal reduction in accuracy for different deployment scenarios.

Projecting Climate Dependent Coastal Flood Risk With a Hybrid Statistical Dynamical Model.

Numerical models for tides, storm surge, and wave runup have demonstrated ability to accurately define spatially varying flood surfaces. However these models are typically too computationally expensive to dynamically simulate the full parameter space of future oceanographic, atmospheric, and hydrologic conditions that will constructively compound in the nearshore to cause both extreme event and nuisance flooding during the 21st century. A surrogate modeling framework of waves, winds, and tides is developed in this study to efficiently predict spatially varying nearshore and estuarine water levels contingent on any combination of offshore forcing conditions. The surrogate models are coupled with a time‐dependent stochastic climate emulator that provides efficient downscaling for hypothetical iterations of offshore conditions. Together, the hybrid statistical‐dynamical framework can assess present day and future coastal flood risk, including the chronological characteristics of individual flood and wave‐induced dune overtopping events and their changes into the future. The framework is demonstrated at Naval Base Coronado in San Diego, CA, utilizing the regional Coastal Storm Modeling System (CoSMoS; composed of Delft3D and XBeach) as the dynamic simulator and Gaussian process regression as the surrogate modeling tool. Validation of the framework uses both in‐situ tide gauge observations within San Diego Bay, and a nearshore cross‐shore array deployment of pressure sensors in the open beach surf zone. The framework reveals the relative influence of large‐scale climate variability on future coastal flood resilience metrics relevant to the management of an open coast artificial berm, as well as the stochastic nature of future total water levels.

Development of a continental shelf acoustic telemetry array to support behavioral research of fish in a high energy ocean environment

Acoustic tracking technology supports the study of behavioral patterns of finfish species over long periods and for long distances across coastal and marine environments. Our research program on elasmobranch movements required deployment of an acoustic array in a high-energy, continental shelf environment off Cape Hatteras, North Carolina. A meta-analysis of elasmobranch and teleost acoustic telemetry literature assisted in developing the anchoring and deployment system for the array. But at that time (2008–2014) the literature did not provide suggestions for cost-effective deployment in a remote, high-energy, offshore environment. Using best available information, we designed and deployed an array known as the “Cape Hatteras Acoustic Array” in Raleigh Bay just south of Cape Hatteras, North Carolina, 0–12 kilometers offshore in waters ranging from 10.6 to 36.5 m deep. At the time, retrieving and redeploying the entire anchoring system was critical to reduce expenditure and minimize structure left on the seafloor in this key commercial fishing area. We describe considerations for the anchoring system design and its deployment and retrieval in this high energy environment affected by alongshore currents, large ocean currents (i.e., Labrador Current and the Gulf Stream), and several storms. While Danforth anchors and heavy chain worked for routinely tended moorings, much heavier anchors and large concrete blocks were necessary for long-term deployments through hurricane seasons. Regular maintenance reduced biofouling of surface lines and equipment deployed on the seafloor with a highflier and surface buoy system marking location of the vertically suspended equipment to minimize interactions with commercial and recreational vessels. Our experience shows that both mooring design and regular retrieval are crucial in maintaining acoustic arrays in challenging marine environments.

Deployment of the linear array with geophones on the fault zone of the 2016 Mw 5.5 Gyeongju earthquake

2016년 9월 12일에 경주에서 발생한 모멘트 규모 5.5의 지진이 발생한 이후, 이와 관련된 공공 안전에 대한 관심이 증폭되었다. 지진이 발생한 이후, 국가 광역 지진관측망, 대학교에서 설치한 임시 지진관측망, 그리고 경주지진 원인 단층 규명을 위한 경주 고밀도 광대역 지진관측망자료는 경주지진과 연관 단층의 특성을 파악하는데 효과적으로 이용되고 있다. 이러한 지진 관측 네트워크의 목적을 공유하며, 경주지진 여진 지역에 약 200m 간격으로 69대의 저비용 3성분 지오폰을 선형으로 배열하여 지진 자료를 획득하였다. 지오폰 선형 배열 관측망은 지진 단층대에 거의 수직하게 배치되었으며, 2020년 11월 17일부터 12월 20일까지 약 한 달간 가동되었다.관측 자료에 대하여 간단한 필터링(2-100 Hz) 만으로 인근에서 발생한 국지지진의 P파와 S파를 뚜렷하게 확인할 수 있었다. 또한 가동 기간 동안 발생한 광역 또는 원거리 지진의 신호를 분석하는데 이용할 수 있을 것으로 기대한다. 조밀한 지오폰 선형 배열 관측 자료는 경주지진의 본진 및 여진과 관련된 원인 단층의 상세한 구조를 규명하는데 기여할 수 있을 것으로 기대한다.

Aftershock sequence of the 2017 Mw 6.5 Jiuzhaigou, China earthquake monitored by an AsA network and its implication to fault structures and strength

SUMMARY We deployed a seismic network near the source region of the 2017 Mw 6.5 Jiuzhaigou earthquake to monitor aftershock activity and to investigate the local fault structure. An aftershock deployment of Array of small Arrays (AsA) and a Geometric Mean Envelop (GME) algorithm are adopted to enhance detection performance. We also adopt a set of association, relocation and matched-filter techniques to obtain a detailed regional catalogue. 16 742 events are detected and relocated, including 1279 aftershocks following the Mw 4.8 aftershock. We develop a joint inversion algorithm utilizing locations of event clusters and focal mechanisms to determine the geometry of planar faults. Six segments were finally determined, in which three segments are related to the Huya fault reflecting a change in fault dip direction near the main shock hypocentre, while the other segments reflect branches showing orthogonal and conjugate geometries with the Huya fault. Aftershocks were active on branching faults between the Huya and Minjiang faults indicating that the main shock may have ruptured both major faults. We also resolve a fault portion with ‘weak strength’ near the main shock hypocentre, which is characterized by limited coseismic slips, concentrated afterslip, low aftershock activities, high b-value and high sensitivity to stress changes. These phenomena can be explained by fault frictional properties at conditional stable sliding status, which may be related to the localized high pore-fluid pressure produced by the fluid intrusion.

Four Knife-Edge Diffraction With Antenna Gain Model for Generic Blockage Modelling

With the recent adoption of millimeter-wave spectrum in cellular communications, deployment of active antenna arrays and use of beamforming become vital to compensate for the increased path loss. However, directional high-frequency signals may suffer heavy attenuations due to blockage effects. Therefore, blockage modelling that adequately incorporates the effects of beamforming becomes increasingly relevant. We propose a Four Knife-Edge Diffraction with antenna Gain (4KED-G) model, a deterministic approach to model blockage with broad applicability. The 4KED-G model advances upon the existing models in its inclusion of both angular antenna gains and the diffraction from all the four edges of a rectangular screen blocker, leading to a more general and flexible blockage modelling approach compared to existing widely accepted blockage models. We theoretically show that the proposed generalised model incorporates the strengths of these existing models, while overcoming their shortcomings in establishing applicability to wider range of blockage scenarios. We validate the generalised model against known knife-edge diffraction blockage models for specific scenarios.

Predicting rootzone soil moisture from surface observations in cropland using an exponential filter

AbstractRootzone soil moisture provides valuable information to guide in‐season management decisions in rainfed and irrigated agricultural systems. Measuring rootzone soil moisture usually requires the deployment of a vertical array of sensors, which can be costly and labor intensive. In this study, we tested the skill of an exponential filter to estimate rootzone soil moisture conditions from a time series of near‐surface soil moisture observations. Daily soil moisture observations from a sensor at 10‐cm depth were used to predict the soil water content at 30‐, 50‐, and 70‐cm depth, and across the entire soil profile (0‐to‐80‐cm depth) in four agricultural fields under irrigated and rainfed conditions. The characteristic time length was the only fitting parameter of the model, which was optimized for each site based on the Nash–Sutcliffe (NS) score. Across the four sites, the mean NS score at individual soil layers ranged from −0.64 to 0.73, but the NS score at the profile level ranged between 0.29 and 0.84. Predictions of soil water storage at the profile level based on near‐surface soil moisture and the exponential filter resulted in average RMSE of 11 mm across the four locations. Our study shows that in agricultural fields the exponential filter performs better when considering the entire soil profile rather than individual soil layers.

Hydrokinetic turbine array analysis and optimization integrating blockage effects and turbine-wake interactions

In order to maximize the energy extraction of a hydrokinetic turbine array deployment, turbines must be positioned judiciously within the array. In fact, it is possible to optimize the array configuration in order to benefit from blockage effects and to avoid negative turbine-wake interactions. The Effective Performance Turbine Model (EPTM) that has recently been proposed is a suitable tool for this purpose, allowing to test and analyze a large number of different configurations at a practical computational cost. In this work, assuming a turbulent flow environment, many vertical-axis turbine array configurations (VAT arrays) are tested to study the effect of local blockage, lateral and longitudinal spacing, array staggering and direction of rotation on turbine performance. It is found that the wake deflection associated to the specific turbine tested and the lateral force it induces has a great impact on the array optimization. Following this, results show that there is no advantage to stagger VATs and that aligned configurations should be preferred. In this context, turbines should rotate inward (looking downstream) with respect to the central plane of the array. Some guidelines are also provided in terms of lateral and longitudinal spacings, with the support of a novel parameter indicating the marginal power provided by the addition of a row of turbines.

Quantifying the effects of tidal turbine array operations on the distribution of marine mammals: Implications for collision risk

Owing to their predictability, tidal currents are an attractive source of renewable energy. However, data on the environmental impacts, especially at array scale, are lacking. We present a spatial analysis of telemetry data, identifying the effects of the presence and operations of the world's first commercial sized tidal turbine array on the movements of an acoustically sensitive marine mammal; the harbour seal (Phoca vitulina). No significant change in at sea distribution was detected between pre and post installation of the 4 turbine array. However, seals showed overt avoidance responses during turbine operations, with a significant decrease in predicted abundance (95% CIs: −11%, −49%) within ∼2 km of the array. These results provide important information for estimating collision rates between seals and tidal turbine arrays and demonstrate an analytical framework which can be used to assess the effect of arrays on other marine animal distributions. Collision risk models used to estimate collision rate between tidal turbines and marine mammals traditionally assume some non-empirical degree of avoidance, or no avoidance. The avoidance response elicited by seals to these devices could reduce the likelihood of direct collisions, with estimated avoidance rates measured here suggesting a decrease in total number of between 0.4% and 2% per annum. Further, given sustained barrier effects were not identified, avoidance may only be occurring during the potentially dangerous periods during operations thereby not restricting movement through the site at all times. However, future environmental impact assessments and spatial planning for array deployments should consider the potential for repulsion of acoustically sensitive top-predators away from ecologically important sites.

Environmental and economic impact of household energy systems with storage in the UK

Households accounted for 35% of total UK electricity consumption in 2019 and have considerable potential to support the target of net-zero CO2 emissions by 2050. However, there is little understanding of the potential to reduce emissions from household energy systems using emissions-responsive battery charging, and existing investigations use average emissions factors rather than marginal. To understand the overall carbon reduction potential of household energy systems, a life cycle assessment has been conducted for a typical house in the UK, with annual electricity consumption of 3960 kWh. Household energy systems comprising solar photovoltaics arrays and battery energy storage systems are assessed using time-series consumption and generation data, determined by combining a validated demand model, marginal emissions factor calculations, storage system models, and assumptions regarding the future grid. Marginal emissions factors are used to calculate the life cycle carbon emissions of electricity consumption. The carbon emissions and financial costs of household electricity consumption have been estimated for different combinations of battery storage, photovoltaics arrays, and smart battery charging systems. Results show that the deployment of a rooftop photovoltaics array and lithium nickel-manganese-cobalt battery operating in response to grid emissions factors could achieve 14 tons of CO2 savings through the system’s life span, though total electricity costs would be increased considerably. The household with just a photovoltaics array and no battery storage could increase total electricity costs by £2170 and achieve 12 tons of CO2 savings through the system’s life span, providing much improved marginal abatement costs over systems with battery storage. The battery operation mode and the characteristics of batteries and photovoltaics systems in carbon emissions reduction are discussed. High cost is the main factor limiting the deployment of household battery systems.