Flywheel Energy Storage In Port Moresby Powering Png''s

Browse technical resources about solar mounting systems, tracker technology, structural design, and installation best practices.

HOME / Flywheel Energy Storage In Port Moresby Powering Png''s - BeTheFuture Solar Foundation & Infrastructure

Related Topics:

Flywheel Energy Storage Port
  • Megawatt-scale flywheel energy storage concept

    Megawatt-scale flywheel energy storage concept

    In FESSs, electric energy is transformed into kinetic energy and stored by rotating a flywheel at high speeds. An FESS operates in three distinct modes: charging, discharging, and holding.


    FAQs about Megawatt-scale flywheel energy storage concept

    What is a flywheel energy storage system?

    First-generation flywheel energy-storage systems use a large steel flywheel rotating on mechanical bearings. Newer systems use carbon-fiber composite rotors that have a higher tensile strength than steel and can store much more energy for the same mass. To reduce friction, magnetic bearings are sometimes used instead of mechanical bearings.

    What is a flywheel/kinetic energy storage system (fess)?

    Thanks to the unique advantages such as long life cycles, high power density, minimal environmental impact, and high power quality such as fast response and voltage stability, the flywheel/kinetic energy storage system (FESS) is gaining attention recently.

    What is a 30 MW flywheel grid system?

    A 30 MW flywheel grid system started operating in China in 2024. Flywheels may be used to store energy generated by wind turbines during off-peak periods or during high wind speeds. In 2010, Beacon Power began testing of their Smart Energy 25 (Gen 4) flywheel energy storage system at a wind farm in Tehachapi, California.

    Is flywheel energy storage commercially viable?

    This project aimed to advance flywheel energy storage technology to commercial viability for utility scale energy storage. To achieve this, the design, manufacturing capability, system cost, storage capacity, efficiency, reliability, safety, and system level operation of flywheel energy storage technology were all addressed in the R&D.

    What are the potential applications of flywheel technology?

    Other opportunities are new applications in energy harvest, hybrid energy systems, and flywheel's secondary functionality apart from energy storage. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

    Can small-scale flywheel energy storage systems be used for buffer storage?

    Small-scale flywheel energy storage systems have relatively low specific energy figures once volume and weight of containment is comprised. But the high specific power possible, constrained only by the electrical machine and the power converter interface, makes this technology more suited for buffer storage applications.

  • The composition and working principle of flywheel energy storage battery

    The composition and working principle of flywheel energy storage battery

    Flywheel energy storage (FES) works by accelerating a rotor () to a very high speed and maintaining the energy in the system as. When energy is extracted from the system, the flywheel's rotational speed is reduced as a consequence of the principle of ; adding energy to the system correspondingly results in an increase in the speed of th.


  • Differences between flywheel energy storage and electrochemical energy storage

    Differences between flywheel energy storage and electrochemical energy storage

    Energy storage technologies, including storage types, categorizations and comparisons, are critically reviewed. Most energy storage technologies are considered, including electrochemical and battery ener. ••A broad and recent review of various energy storage types is provided.••Applications of v. Energy systems play a key role in harvesting energy from various sources and converting it t. The various types of energy storage can be divided into many categories, and here most energy storage types are categorized as electrochemical and battery energy storage, thermal. Energy storage is an enabling technology for various applications such as power peak shaving, renewable energy utilization, enhanced building energy systems, and advanced transp. In this section several energy storage types are described and/or compared from technical and economic perspectives, rather than their classifications and principles. Simila.

    [PDF Version]

    FAQs about Differences between flywheel energy storage and electrochemical energy storage

    Are flywheel energy storage systems feasible?

    Accepted: 02 March 2024 Abstract - This study gives a critical review of flywheel energy storage systems and their feasibility in various applications. Flywheel energy storage systems have gained increased popularity as a method of environmentally friendly energy storage.

    How can flywheels be more competitive to batteries?

    The use of new materials and compact designs will increase the specific energy and energy density to make flywheels more competitive to batteries. Other opportunities are new applications in energy harvest, hybrid energy systems, and flywheel's secondary functionality apart from energy storage.

    How does Flywheel energy storage work?

    Flywheel energy storage (FES) works by accelerating a rotor (flywheel) to a very high speed and maintaining the energy in the system as rotational energy.

    Are flywheels a good alternative to battery energy storage?

    Khodadoost et al. suggest that flywheels are favorable options for integration with wind and PV systems compared to battery energy storage systems since variations in their output power occur in a short period of time.

    Are flywheel-based hybrid energy storage systems based on compressed air energy storage?

    While many papers compare different ESS technologies, only a few research, studies design and control flywheel-based hybrid energy storage systems. Recently, Zhang et al. present a hybrid energy storage system based on compressed air energy storage and FESS.

    What is a flywheel/kinetic energy storage system (fess)?

    Thanks to the unique advantages such as long life cycles, high power density, minimal environmental impact, and high power quality such as fast response and voltage stability, the flywheel/kinetic energy storage system (FESS) is gaining attention recently.

  • How long can the flywheel energy storage system last

    How long can the flywheel energy storage system last

    Flywheels can be expected to last upwards of 20 years and cycle more than 20,000 times, which is high in comparison to lead-acid (2,000 cycles), lithium-ion (<10,000 cycles) and sodium-sulfur batte.


    FAQs about How long can the flywheel energy storage system last

    How long does a flywheel energy storage system last?

    Flywheel energy storage systems have a long working life if periodically maintained (>25 years). The cycle numbers of flywheel energy storage systems are very high (>100,000). In addition, this storage technology is not affected by weather and climatic conditions . One of the most important issues of flywheel energy storage systems is safety.

    How does a flywheel work?

    A flywheel operates on the principle of storing energy through its rotating mass. Think of it as a mechanical storage tool that converts electrical energy into mechanical energy for storage. This energy is stored in the form of rotational kinetic energy.

    How does Flywheel energy storage work?

    Flywheel energy storage (FES) works by accelerating a rotor (flywheel) to a very high speed and maintaining the energy in the system as rotational energy.

    What is a flywheel energy storage system (fess)?

    Think of it as a mechanical storage tool that converts electrical energy into mechanical energy for storage. This energy is stored in the form of rotational kinetic energy. Typically, the energy input to a Flywheel Energy Storage System (FESS) comes from an electrical source like the grid or any other electrical source.

    Are flywheels the future of energy storage?

    Global decarbonisation requires green energy storage solutions, of which flywheels have been touted as one of its principal proponents. These clever yet simple mechanical systems are certainly part of the energy storage future, just perhaps not in the way you envisage. Read on to find out why! Contents What is a flywheel?

    How efficient is a flywheel system?

    Due to their simple design and frictionless characteristics, flywheel systems can reach very high efficiencies of 70-95%, where only a small fraction of the energy is lost during storage.

  • Flywheel energy storage and new energy storage

    Flywheel energy storage and new energy storage

    Flywheel energy storage (FES) works by accelerating a rotor () to a very high speed and maintaining the energy in the system as. When energy is extracted from the system, the flywheel's rotational speed is reduced as a consequence of the principle of ; adding energy to the system correspondingly results in an increase in the speed of th.


  • Power plant installation of flywheel energy storage

    Power plant installation of flywheel energy storage

    By tracking the progress of flywheel energy storage project in recent years, this paper introduces the main subsystem of flywheel energy storage technology and the technical route of major companies and research institutions, and concludes that the engineering application of flywheel energy storage in power system mainly includes grid frequency modulation, renewable energy consumption and micro grid support.


    FAQs about Power plant installation of flywheel energy storage

    Are flywheel energy storage systems environmentally friendly?

    Flywheel energy storage systems (FESS) are considered environmentally friendly short-term energy storage solutions due to their capacity for rapid and efficient energy storage and release, high power density, and long-term lifespan. These attributes make FESS suitable for integration into power systems in a wide range of applications.

    What is the largest flywheel energy storage system in the world?

    Image: Shenzen Energy Group. A project in China, claimed as the largest flywheel energy storage system in the world, has been connected to the grid. The first flywheel unit of the Dinglun Flywheel Energy Storage Power Station in Changzhi City, Shanxi Province, was connected by project owner Shenzen Energy Group recently.

    What is a flywheel energy storage array?

    A project that contains two combined thermal power units for 600 MW nominal power coupling flywheel energy storage array, a capacity of 22 MW/4.5 MWh, settled in China. This project is the flywheel energy storage array with the largest single energy storage and single power output worldwide.

    What is the Dinglun flywheel energy storage power station?

    The Dinglun Flywheel Energy Storage Power Station, the World's Largest Flywheel Energy Storage Project, represents a significant step forward in sustainable energy. Its role in grid frequency regulation and support for renewable energy will help stabilize power systems as China continues to increase its reliance on wind and solar energy.

    Where is China's first large-scale flywheel energy storage project?

    From ESS News China has connected to the grid its first large-scale standalone flywheel energy storage project in Shanxi Province's city of Changzhi. The Dinglun Flywheel Energy Storage Power Station broke ground in July last year.

    How does a flywheel energy storage system work?

    A flywheel energy storage system works by spinning a large, heavy wheel, called a flywheel at very high speeds. The energy is stored as rotational kinetic energy in the spinning wheel. When electricity is needed, the flywheel's rotational speed is reduced, and the stored kinetic energy is converted back into electrical power using a generator.

  • Do flywheel energy storage products have high technical requirements

    Do flywheel energy storage products have high technical requirements

    Flywheel energy storage (FES) works by accelerating a rotor () to a very high speed and maintaining the energy in the system as. When energy is extracted from the system, the flywheel's rotational speed is reduced as a consequence of the principle of ; adding energy to the system correspondingly results in an increase in the speed of th.


    FAQs about Do flywheel energy storage products have high technical requirements

    Are flywheel energy storage systems feasible?

    Accepted: 02 March 2024 Abstract - This study gives a critical review of flywheel energy storage systems and their feasibility in various applications. Flywheel energy storage systems have gained increased popularity as a method of environmentally friendly energy storage.

    How can flywheels be more competitive to batteries?

    The use of new materials and compact designs will increase the specific energy and energy density to make flywheels more competitive to batteries. Other opportunities are new applications in energy harvest, hybrid energy systems, and flywheel's secondary functionality apart from energy storage.

    What are the potential applications of flywheel technology?

    Other opportunities are new applications in energy harvest, hybrid energy systems, and flywheel's secondary functionality apart from energy storage. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

    How does Flywheel energy storage work?

    Flywheel energy storage (FES) works by accelerating a rotor (flywheel) to a very high speed and maintaining the energy in the system as rotational energy.

    Can small-scale flywheel energy storage systems be used for buffer storage?

    Small-scale flywheel energy storage systems have relatively low specific energy figures once volume and weight of containment is comprised. But the high specific power possible, constrained only by the electrical machine and the power converter interface, makes this technology more suited for buffer storage applications.

    Can flywheel technology improve the storage capacity of a power distribution system?

    A dynamic model of an FESS was presented using flywheel technology to improve the storage capacity of the active power distribution system . To effectively manage the energy stored in a small-capacity FESS, a monitoring unit and short-term advanced wind speed prediction were used . 3.2. High-Quality Uninterruptible Power Supply

  • Flywheel energy storage power station access requirements

    Flywheel energy storage power station access requirements

    A flywheel-storage power system uses a for energy storage, (see ) and can be a comparatively small storage facility with a peak power of up to 20 MW. It typically is used to stabilize to some degree power grids, to help them stay on the grid frequency, and to serve as a short-term compensation storage. Unlike common storage power plants, such as the.


    FAQs about Flywheel energy storage power station access requirements

    What is a flywheel-storage power system?

    A flywheel-storage power system uses a flywheel for energy storage, (see Flywheel energy storage) and can be a comparatively small storage facility with a peak power of up to 20 MW. It typically is used to stabilize to some degree power grids, to help them stay on the grid frequency, and to serve as a short-term compensation storage.

    What is a 10 MJ flywheel energy storage system?

    A 10 MJ flywheel energy storage system, used to maintain high quality electric power and guarantee a reliable power supply from the distribution network, was tested in the year 2000. The FES was able to keep the voltage in the distribution network within 98–102% and had the capability of supplying 10 kW of power for 15 min . 3.5.7.

    Can small-scale flywheel energy storage systems be used for buffer storage?

    Small-scale flywheel energy storage systems have relatively low specific energy figures once volume and weight of containment is comprised. But the high specific power possible, constrained only by the electrical machine and the power converter interface, makes this technology more suited for buffer storage applications.

    Could flywheel technology be a key part of our energy storage needs?

    Flywheel technology has the potential to be a key part of our Energy Storage needs, writes Prof. Keith Robert Pullen: Electricity power systems are going through a major transition away from centralised fossil and nuclear based generation towards renewables, driven mainly by substantial cost reductions in solar PV and wind.

    What is a flywheel/kinetic energy storage system (fess)?

    Thanks to the unique advantages such as long life cycles, high power density, minimal environmental impact, and high power quality such as fast response and voltage stability, the flywheel/kinetic energy storage system (FESS) is gaining attention recently.

    Where does a flywheel energy storage system come from?

    Prof. Dr.-Ing. Günter Keller references including diagrams, figures and sketches. The input energy for a Flywheel energy storage system is usually drawn from an electrical source coming from the grid or any other source of electrical energy.

  • Necessity of flywheel energy storage motor

    Necessity of flywheel energy storage motor

    Flywheels have attributes of a high cycle life, long operational life, high round-trip efficiency, high power density, low environmental impact, and can store megajoule (MJ) levels of energy with no upper limit when configured in banks.


    FAQs about Necessity of flywheel energy storage motor

    How efficient is a flywheel energy storage system?

    Their efficiency is high during energy storage and energy transfer (>90 %). The performance of flywheel energy storage systems operating in magnetic bearing and vacuum is high. Flywheel energy storage systems have a long working life if periodically maintained (>25 years).

    Can flywheels be used for power storage systems?

    Flywheels are now a possible technology for power storage systems for fixed or mobile installations. FESS have numerous advantages, such as high power density, high energy density, no capacity degradation, ease of measurement of state of charge, don't require periodic maintenance and have short recharge times .

    Can small applications be used instead of large flywheel energy storage systems?

    Small applications connected in parallel can be used instead of large flywheel energy storage systems. There are losses due to air friction and bearing in flywheel energy storage systems. These cause energy losses with self-discharge in the flywheel energy storage system.

    What is a flywheel/kinetic energy storage system (fess)?

    Thanks to the unique advantages such as long life cycles, high power density, minimal environmental impact, and high power quality such as fast response and voltage stability, the flywheel/kinetic energy storage system (FESS) is gaining attention recently.

    What are the disadvantages of Flywheel energy storage systems?

    In addition, this storage technology is not affected by weather and climatic conditions . One of the most important issues of flywheel energy storage systems is safety. As a result of mechanical failure, the rotating object fails during high rotational speed poses a serious danger. One of the disadvantages of these storage systems is noise.

    What is a flywheel & how does it work?

    Flywheels with the main attributes of high energy efficiency, and high power and energy density, compete with other storage technologies in electrical energy storage applications, as well as in transportation, military services, and space satellites .

  • Flywheel energy storage power control

    Flywheel energy storage power control

    Flywheel energy storage systems (FESSs) are widely used for power regulation in wind farms as they can balance the wind farms' output power and improve the wind power grid connection rate.


    FAQs about Flywheel energy storage power control

    Are flywheel energy storage systems environmentally friendly?

    Flywheel energy storage systems (FESS) are considered environmentally friendly short-term energy storage solutions due to their capacity for rapid and efficient energy storage and release, high power density, and long-term lifespan. These attributes make FESS suitable for integration into power systems in a wide range of applications.

    Can flywheel energy storage system array improve power system performance?

    Moreover, flywheel energy storage system array (FESA) is a potential and promising alternative to other forms of ESS in power system applications for improving power system efficiency, stability and security . However, control systems of PV-FESS, WT-FESS and FESA are crucial to guarantee the FESS performance.

    What is a magnetically suspended flywheel energy storage system (MS-fess)?

    The magnetically suspended flywheel energy storage system (MS-FESS) is an energy storage equipment that accomplishes the bidirectional transfer between electric energy and kinetic energy, and it is widely used as the power conversion unit in the uninterrupted power supply (UPS) system.

    How does a flywheel energy storage system work?

    This flywheel energy storage system also requires motor speed control at the nominal speed level required by the generator to produce the optimal output voltage . A high-efficiency control system is required to ensure that the motor can drive the generator at the required speed.

    What is a flywheel energy storage unit?

    A flywheel energy storage unit is a mechanical system designed to store and release energy efficiently. It consists of a high-momentum flywheel, precision bearings, a vacuum or low-pressure enclosure to minimize energy losses due to friction and air resistance, a motor/generator for energy conversion, and a sophisticated control system.

    What is a flywheel energy storage system (fess)?

    The flywheel energy storage system (FESS), as an important energy conversion device, could accomplish the bidirectional conversion between the kinetic energy of the flywheel (FW) rotor and the electrical energy of the grid 1, 2, 3.

  • Top 10 Flywheel Energy Storage Companies

    Top 10 Flywheel Energy Storage Companies

    Specifically, the Top 10 flywheel energy storage companies in China are QIFENG POWER, HHE, CANDELA, HUACHI KINETIC ENERGY, KTS, rotonix, FORYON, SINOMACH. HE, XEMC and JSTI respectively.


    FAQs about Top 10 Flywheel Energy Storage Companies

    How many flywheel energy storage companies are there in China?

    At present, there are many companies producing flywheel energy storage products in the world, and companies including Top 10 flywheel energy storage companies in China are actively deploying flywheel energy storage technology. If playback doesn't begin shortly, try restarting your device.

    What is a high efficiency flywheel energy storage system?

    High Efficiency Flywheel energy storage systems offer high round-trip efficiency, typically around 85-95%. This means that a significant portion of the energy used to charge the flywheel can be recovered during discharge. 2. Rapid Response Time These systems provide a quick response to changes in energy demand.

    What are the benefits of a flywheel system?

    2. Renewable Energy Integration These systems are particularly effective for integrating renewable energy sources, such as wind and solar. Flywheels can store excess energy generated during peak production times and release it when generation is low, ensuring a consistent energy supply.

    What is advanced flywheel energy storage?

    Advanced Flywheel Energy Storage enabling enhanced power quality and reduced TCO. AMT has developed a flywheel energy storage system that is capable of providing up to 5.5 kilowatt hours of energy storage and delivering 4 kilowatt hours at a given time. The flywheel rotor is made of carbon fibers allowing for greater energy...

    How does a flywheel energy storage system work?

    Flywheel energy storage systems operate by converting electrical energy into kinetic energy. This process involves a rotor, which spins at high speeds within a vacuum to minimize friction and energy loss. When energy is supplied, it accelerates the rotor, storing energy in the form of rotational motion.

    What is a flywheel energy storage system (fess)?

    To solve this problem, London-based startup Levistor has developed an innovative Flywheel Energy Storage System (FESS), which acts as a kinetic battery. This technology stores energy from the grid during periods of low demand and releases it rapidly when an EV needs a quick charge. It can deliver 100 miles of range in just five minutes.

  • The role of flywheel energy storage motor

    The role of flywheel energy storage motor

    Flywheel energy storage technology uses reversible bidirectional motors (electric motor/generator) to facilitate the conversion between electrical energy and the mechanical energy of a high-speed rotating flywheel.


    FAQs about The role of flywheel energy storage motor

    What is the main technology of Flywheel energy storage system?

    The main power circuit technology is mature, and the main research is the conversion control algorithm. China has successfully developed MW-class motor converters for flywheel energy storage systems. 4. FES System

    How does a high-speed flywheel energy storage system work?

    Zhang employed a high-speed flywheel energy storage system (FESS) charge–discharge control method based on the DC traction network voltage to achieve effective operation of the FESS in the subway traction power supply system .

    What is a flywheel/kinetic energy storage system (fess)?

    Thanks to the unique advantages such as long life cycles, high power density, minimal environmental impact, and high power quality such as fast response and voltage stability, the flywheel/kinetic energy storage system (FESS) is gaining attention recently.

    How to design a flywheel energy storage motor?

    The design of the motor for flywheel energy storage mainly adopts the stator core, winding, magnet, and a matching optimization to improve the power and efficiency. The challenge in motor design is to reduce the loss of the permanent magnet motor rotor and prevent the failure of the motor caused by high-temperature rise. 3.3.

    How can flywheels be more competitive to batteries?

    The use of new materials and compact designs will increase the specific energy and energy density to make flywheels more competitive to batteries. Other opportunities are new applications in energy harvest, hybrid energy systems, and flywheel's secondary functionality apart from energy storage.

    Could flywheels be the future of energy storage?

    Flywheels, one of the earliest forms of energy storage, could play a significant role in the transformation of the electrical power system into one that is fully sustainable yet low cost.

  • China s communication base station flywheel energy storage hybrid power supply

    China s communication base station flywheel energy storage hybrid power supply

    Upon completion, it is expected to become the first independent flywheel + lithium battery hybrid energy storage power station in China, capable of meeting both frequency regulation and peak shaving demands, thus contributing to the safe and stable operation of the power grid.


    FAQs about China s communication base station flywheel energy storage hybrid power supply

    Where is China's largest flywheel energy storage system located?

    Home » Clean Technology » China Connects World's Largest Flywheel Energy Storage Project to the Grid China has connected its first large-scale, grid-connected flywheel energy storage system to the power grid in Changzhi, Shanxi Province.

    What is China's biggest flywheel system?

    China has connected the world's biggest flywheel system to its national grid. Built in the city of Changzhi, Shanxi Province, the $48m Dinglun Flywheel Energy Storage Power Station can store 30MW of energy in kinetic form, the Interesting Engineering website reports.

    What is the Dinglun flywheel energy storage power station?

    The Dinglun Flywheel Energy Storage Power Station, the World's Largest Flywheel Energy Storage Project, represents a significant step forward in sustainable energy. Its role in grid frequency regulation and support for renewable energy will help stabilize power systems as China continues to increase its reliance on wind and solar energy.

    What is flywheel energy storage technology?

    Flywheel energy storage technology is a mechanical energy storage form. It works by accelerating the rotor (flywheel) at a very high speed. This maintains the energy as kinetic energy in the system. This technology has high power and energy density, rapid response and is highly efficient in comparison to pumped hydro or compressed air.

    What is a high-speed magnetic levitation flywheel storage system?

    This flywheel storage system, developed by Shenzhen Energy Group with technology from BC New Energy, consists of 120 high-speed magnetic levitation flywheel units. These units are designed to store energy in the form of kinetic energy by spinning flywheels at high speeds.

    Who built the world's biggest flywheel system?

    BC New Energy was the technology provider and Shenzhen Energy Group was the principal investor. The Dinglung project takes the title of world's biggest flywheel system from the 20MW Beacon Power flywheel station in Stephentown, New York. This went live in 2014 and cost $52m to build.

  • Photovoltaic energy storage wind power generation project

    Photovoltaic energy storage wind power generation project

    Clean energy sources like wind and solar have a huge potential to lessen reliance on fossil fuels. Due to the stochastic nature of various energy sources, dependable hybrid systems have recently been d.


    FAQs about Photovoltaic energy storage wind power generation project

    Is energy storage based on hybrid wind and photovoltaic technologies sustainable?

    To resolve these shortcomings, this paper proposed a novel Energy Storage System Based on Hybrid Wind and Photovoltaic Technologies techniques developed for sustainable hybrid wind and photovoltaic storage systems. The major contributions of the proposed approach are given as follows.

    What are the major contributions of hybrid solar PV & photovoltaic storage system?

    The major contributions of the proposed approach are given as follows. Hybrid solar PV and wind frameworks, as well as a battery bank connected to an air conditioner Microgrid, is developed for sustainable hybrid wind and photovoltaic storage system. The heap voltage's recurrence and extent are constrained by the battery converter.

    What is the wind power model?

    The model is a new energy comprehensive demonstration project that integrates wind power, photovoltaic cells, energy storage devices and smart power transmission.

    Do technological improvements lead to a faster growth of PV and wind power?

    In our optimal case, the projected cost reduction by technological improvements 20 and the low-cost energy sources identification at sub-national scales 23 together lead to a faster growth of PV and wind-power generation than the prediction based on the historical trends.

    What is a wind-solar hybrid power system?

    A new energy storage technology combining gravity, solar, and wind energy storage. The reciprocal nature of wind and sun, the ill-fated pace of electricity supply, and the pace of commitment of wind-solar hybrid power systems.

    Can wind and solar be used to provide electricity?

    Clean energy sources like wind and solar have a huge potential to lessen reliance on fossil fuels. Due to the stochastic nature of various energy sources, dependable hybrid systems have recently been developed. This paper's major goal is to use the existing wind and solar resources to provide electricity.

Solar Mounting & Structural Insights