Generated Power Density Research Articles

The station blackout accident in a dual-cooled annular fuel of a VVER-1000 reactor with application of portable pumps for mitigating the accident

The station blackout accident is clearly a very serious problem that jeopardizes the safety barrier of nuclear reactor and ascends the core integrity steeply. The dual-cooled annular fuel has been introduced to boost the generated power density and safety margins. The fuel is cooled both internally and externally by allowing the liquid to flow on inner and outer heated surfaces. The fuel peak temperature can be reduced substantially by decreasing the fuel rod cladding heat flux leading to an increment on the DNBR. In this paper, a dual cooled annular fuel a VVER-1000 is investigated in this accident scenarios. The deployment of portable pumps for injecting coolant to dual cooled annular fuel core to mitigate this accident is also considered. The effect of accident tolerant fuel rod cladding is also investigated. The RELAP5 model is used to model the annular fuel to perform the analysis. The results are compared to traditional solid fuel geometry.

Floating treatment wetlands integrated with microbial fuel cell for the treatment of urban wastewaters and bioenergy generation

The objective of the present study was to develop a combined system composed of anaerobic biofilter (AF) and floating treatment wetlands (FTW) coupled with microbial fuel cells (MFC) in the buoyant support for treating wastewater from a university campus and generate bioelectricity. The raw wastewater was pumped to a 1450 L tank, operated in batch flow and filled with plastic conduits. The second treatment stage was composed of a 1000 L FTW box with a 200 L plastic drum inside (acting as settler in the entrance) and vegetated with mixed ornamental plants species floating in a polyurethane support fed once a week with 700 L of wastewater. In the plant roots, graphite rods were placed to act as cathodes, while on the bottom of the box 40 graphite sticks inside a plastic hose with a stainless-steel cable acting as the anode chamber. Open circuit voltages were daily measured for 6 weeks, and later as closed circuit with the connection of 1000 Ω resistors. Plant harvestings were conducted, in which biomass production and plant uptake from each of the species were measured. On average, system was efficient in reducing BOD5 (55.1%), COD (71.4%), turbidity (90.9%) and total coliforms (99.9%), but presented low efficiencies regarding total N (8.4%) and total P (11.4%). Concerning bioenergy generation, voltage peaks and maximum power density were observed on the feeding day, reaching 225 mV and 0.93 mW/m2, respectively, and in general decaying over the 7 days. In addition, plant species with larger root development presented higher voltage values than plants with the smaller root systems, possible because of oxygen release. Therefore, the combined system presented potential of treating wastewater and generating energy by integrating FTW and MFC, but further studies should investigate the FTW-MFC combination in order to improve its treatment performance and maximize energy generation.

Metal Island Structure as a Power Booster for High‐Performance Triboelectric Nanogenerators

AbstractThe development of the Internet of Things requires the availability of compact and efficient power sources for the supply of autonomous systems. In recent times, electromechanical transduction devices like triboelectric nanogenerators (TENGs) have gained strong attention as they permit simple, robust, and cost‐effective techniques. However, TENGs generally do not achieve the electrical power density required for the targeted applications, and the challenges of optimization are therefore to increase their generated power density. In this work, a multilayer flexible composite structure is developed by employing an insulator–metal–insulator island architecture in place of a single insulator material to accumulate and store the charges created by triboelectrification. This increase in stored charges has a strong effect in inducing free charges on the electrodes resulting in a maximum output power density of 4.8 W m−2, which is ≈150‐fold increase compared to the structure without metal inclusions. The results demonstrate a maximum charge density of 1076.56 µC m−2, which is to the knowledge, the best charge density value ever reported for TENGs in ambient working conditions. Therefore, this work proposes a new direction to significantly increase the electrical power density in obtaining high‐performance triboelectric nanogenerators attractive to future applications for active sensors and portable electronics.

Epitaxy Enhancement of Piezoelectric Properties in P(VDF‐TrFE) Copolymer Films and Applications in Sensing and Energy Harvesting

AbstractWith the rapid development of wearable and flexible electronics, energy harvesting from the environment has attracted much attention. As one representative piezoelectric polymer, poly(vinylidene fluoride‐trifluoroethylene) [P(VDF‐TrFE)] is an expected candidate for mechanical energy harvesting and self‐powered mechanical sensors due to its flexibility and moderate piezoelectricity. However, low crystallinity and electroactivity limit its electric performance. Controllable modulation of microstructure and crystallization is one feasible measure to enhance piezoelectric property. Here the piezoelectric properties of epitaxial P(VDF‐TrFE) films which are fabricated via removable polytetrafluoroethylene template method are reported. Piezoelectric measurement between 50 and 800 Hz presents an averaged d33 coefficient of −40.7 pC N−1 for epitaxial film, ≈61% enhancement to that of non‐epitaxial one. Transverse piezoelectric experiment indicated that epitaxy process enhanced open‐circuit voltage and short‐circuit current outputs. Simple piezoelectric energy harvesters are prepared by depositing both epitaxial and nonepitaxial films on flexible polyimide substrates. Epitaxial film shows a maximum generated power density of 0.118 µW cm−2 and energy conversion efficiency of 0.81%, both of which are much larger than those from nonepitaxial film (0.047 µW cm−2 and 0.30%). Piezoelectric films are used to monitor bending, punching, twisting and finger tapping operations, where epitaxial film exhibited larger open‐circuit voltage responses than nonepitaxial one.

Si0.97Ge0.03 microelectronic thermoelectric generators with high power and voltage densities

Microelectronic thermoelectric generators are one potential solution to energizing energy autonomous electronics, such as internet-of-things sensors, that must carry their own power source. However, thermoelectric generators with the mm2 footprint area necessary for on-chip integration made from high thermoelectric figure-of-merit materials have been unable to produce the voltage and power levels required to run Si electronics using common temperature differences. We present microelectronic thermoelectric generators using Si0.97Ge0.03, made by standard Si processing, with high voltage and power generation densities that are comparable to or better than generators using high figure-of-merit materials. These Si-based thermoelectric generators have <1 mm2 areas and can energize off-the-shelf sensor integrated circuits using temperature differences ≤25 K near room temperature. These generators can be directly integrated with Si circuits and scaled up in area to generate voltages and powers competitive with existing thermoelectric technologies, but in what should be a far more cost-effective manner.

Nonisothermal two‐phase modeling of the effect of linear nonuniform catalyst layer on polymer electrolyte membrane fuel cell performance

AbstractIn this research, it is investigated to numerically evaluate the performance of a polymer electrolyte membrane fuel cell (PEMFC). The performance is investigated through the nonuniformity gradient loading at the catalyst layer (CL) of the considered PEMFC. Computational fluid dynamics is used to simulate a 2D domain in which a steady‐state laminar compressible flow in two‐phase for the PEMFC has been considered. In this case, a particular nonuniform variation inside the CL along the channel is assumed. The nonuniform gradient is created using a nonisothermal domain to predict the flooding effects on the performance of the PEMFC. The computational domain is considered as the cathode of PEMFC, which is divided into three regions: a gas channel, a gas diffusion layer, and a CL. The loading variation inside the catalyst is defined as a constant slope along the channel. In order to find the optimum slope, different slope angles are analyzed. The results point out that the nonuniform loading distribution of the catalyst (platinum) along the channel could improve the fuel cell performance up to 1.6% and 5% for power density and voltage generation, respectively. It is inferred that it is better to use more catalyst in the final section of the channel if the performance is the main concern.

Enhanced processing of exhaust gas and power generation by connecting mini-tubular microbial fuel cells in series with a biotrickling filter

Tubular microbial fuel cells (Tube-MFCs) were placed on top of a biotrickling filter-microbial fuel cell (BTF-MFC) to form a tubular biotrickling filter microbial fuel cell (Tube-BTF-MFC) system. Adding Tube-MFCs greatly increased the power output of a Tube-BTF-MFC in treating ethyl acetate (EA). With a progressive water flow pattern generated by circulating water spray, the Tube-MFC can reduce the sharing of electrolyte between anode chambers of MFCs and improve the power output of Tube-BTF-MFC. With 129.8 g/m3·h of EA, the Tube-BTF-MFC exhibited an EA removal efficiency of 93% and a closed circuit voltage (186.5 mV). The maximum elimination capacity of EA by the Tube-BTF-MFC was 1.47 times greater than that of the BTF-MFC, while the highest generated power density was 2.13 times greater. Adding Tube-MFCs to a BTF-MFC system can effectively improve its removal efficiency for EA and increase its power output. The proposed Tube-BTF-MFC can be used to treat industrially emitted gaseous volatile organic compounds while generating electricity.

Isolation and characterization of ACC Deaminase Producing Endophytic Bacillus mojavensis PRN2 from Pisum sativum.

Background: Endophytic bacteria reside inside healthy plant tissues and provide several benefits to their host, and help them to tolerate various stresses. Aminocyclopropane-1-carboxylate deaminase (ACCD) production is one of the mechanisms by which these bacteria help the plant to survive under ethylene stressObjectives: The main focus of this study was to isolate endophytic bacteria and effectively screen them for ACCD production. The selected isolate was identified and assessed for plant growth-promoting potential under pot conditions.Materials and Methods: Endophytic bacteria were isolated from root nodules of Pisum sativum plants, grown in northern India (Haryana state). ACCD activity was initially screened on DF minimal salt medium with ACC as a sole nitrogen source. To narrow down the number of the isolates, another screening method was adopted using a modified medium containing indicator dyes along with ACC. The strain producing ACCD as well as a significant amount of Indole 3 acetic acid (IAA) was identified using 16S rDNA gene sequencing and amplification of acdS gene. Its ability to promote plant growth was evaluated under pot culture conditions.Results: Twenty-six endophytic bacteria were isolated from nodules of P. sativum plants. Sixteen isolates showed growth on DF minimal salts medium supplemented with ACC along with negative control. On the modified medium containing indicator dyes, two isolates, PJN13 and PJN17, showed zones of the color gradient. The ACC deaminase activity was further confirmed by enzymatic assay. The strains PJN13 and PJN17 produced 160 and 130 µM of α-ketobutyrate m.g-1 protein h-1, respectively. The IAA production in the strain PJN13 (79.04 ± 0.78 µg.mL -1) was significantly more than that in the strain PJN17 (38.36 ± 1.89 µg.mL-1). It could enhance pea plant growth parameters, including root and shoot length and fresh and dry weight from 1 to 4 times compare to the control (untreated pea plants) under pot conditions. The results of 16S rDNA amplification and sequencing showed that PJN13 has maximum similarity to Bacillus mojavensis, and the sequence submitted to GenBank under accession number MH298523. Also, a band about 800 bp was amplified for the acdS gene.Conclusions: Though Bacillus is known as a predominant non-rhizobial endophytic genus, however in the present study, a B. mojavensisBacillus mojavensis PRN2 (MH298523) was reported for the first time as an endophyte from the nodules of pea plants. The isolated strain possesses ACC deaminase activity along with IAA production capability, and high potentials as PGPE (Plant growth-promoting endophyte) for plant growth, so it has potential to be used as biofertilizers in pea fields.

Simultaneous Investigation of Three Effective Parameters of Substrate, Microorganism Type and Reactor Design on Power Generation in a Dual-Chamber Microbial Fuel Cells

Background: The use of Microbial Fuel Cells (MFCs) has been expanded in recent years due to their ability in producing bioelectricity and treating wastewater simultaneously. However, there are still some obstacles to use MFC on an industrial scale. Regardless of the restriction of electrodes applied in the electron transferring process, there are also some other factors having strong roles in reducing the power density of MFCs.Objectives: In this paper, the effect of three categories of limiting factors such as kinds of microorganisms (Saccharomyces cerevisiae and Shewanella sp.), substrate type (Glucose and acetate), and features reactor components have been investigated on the power density generation. Simultaneous investigation of these parameters and demonstration of which parameters would induce more power density can help to improve the scale‑up of MFCs.Materials and Methods: Two types of MFCs with different designs were constructed and inoculated with pure cultures of Saccharomyces cerevisiae PTCC 5269 and Shewanella sp. The OCV (Open Circuit Voltage) and polarization curves of MFCs were measured when the quasi‑steady‑state condition was observed.Results: Based on results, utilizing acetate in the presence of both microorganisms led to approximately 60% higher power density compared to glucose. The comparison of maximum power densities of different reactor designs indicated an approximately 17-70 % increase of power generation. However, the resultant shows modification of reactor design even when other parameters are not optimal can increase power density more than three times.Conclusion: Actually, reactor design has the most important role in the power density with the MFC while the effects of substrate and microorganism parameters are not inappreciable.

Fabrication of Conducting Nanochannels Using Accelerator for Fuel Cell Membrane and Removal of Radionuclides: Role of Nanoparticles.

Latent tracks in pure polymer and its nanohybrid are fabricated by irradiating with swift heavy ions (SHI) (Ag+) having 140 MeV energy followed by selective chemical etching of the amorphous path, caused by the irradiation of SHI, to generate nanochannels of size ∼80 nm. Grafting is done within the nanochannels utilizing free radicals generated from the interaction of high-energy ions, followed by tagging of ionic species to make the nanochannels highly ion-conducting. The uniform dispersion of two-dimensional nanoparticles better controls the size and number density of the nanochannels and, thereby, converts them into an effective membrane. The nanoparticle and functionalization induce a piezoelectric β-phase in the membrane. The functionalized membrane removes the radioactive nuclide like 241Am+3 (α-emitting source) efficiently (∼80% or 0.35 μg/cm2) from its solution/waste. This membrane act as a corrosion inhibitor (92% inhibition efficiency) together with its higher proton conduction (0.13 S/m) ability. The higher ion-exchange capacity, water uptake, ion conduction, and high sorption by the nanohybrid membrane are explored with respect to the extent of functionalization and control over nanochannel dimension. A membrane electrode assembly has been fabricated to construct a complete fuel cell, which exhibits superior power generation (power density of 45 mW/cm2 at a current density of 298 mA/cm2) much higher than that of the standard Nafion, measured in a similar condition. Further, a piezoelectric matrix along with its anticorrosive property, high sorption characteristics, and greater power generation makes this class of material a smart membrane that can be used for many different applications.

On the volume power density of radial thermoelectric generators

We examine the volume power density of radial thermoelectric generators (TEGs). Radial, or tubular, TEGs have been considered as an alternative to the usual flat-plate TEGs due to its improved geometric match to typical curved heat sources and high surface power density. However, surface power density is not the only important performance index in realistic situations. Especially for TEGs with inorganic materials that have high raw material prices, volume power density can be important as well. In this note, an analytic model of a radial TEG is studied with a numerical trial-and-error approach for investigating its volume power density. At the same time, an alternative, approximate method of estimating the maximum power of the radial TEG is presented. Using these two approaches, we estimate the volume power density of a skutterudite-based radial TEG and compare the results to those of a flat-plate TEG. The volume power density of the radial TEG is significantly lower than that of the flat-plate TEG. For example, our calculation for a representative case with free convection on the cold side shows that the volume power density of the radial TEG will be 107 W/m3 at best. The result improves with forced convection, and our calculation for a representative case with forced convection on the cold side exhibits the maximum volume power density of 24 100 W/m3. All these values turn out to be smaller roughly by one order of magnitude than the maximum volume power densities of comparable flat-plate TEGs. Such a low volume power density indicates lower economic feasibility of the radial TEG with expensive inorganic thermoelectric materials. This is also explicitly discussed by presenting the high cost per watt of the radial TEG. It is therefore suggested that radial TEGs with less expensive organic materials may be more acceptable than those with inorganic ones.

Concept design of a high power superconducting generator for future hybrid-electric aircraft

The reduction of emission is a key goals for the aviation industry. One enabling technology to achieve this goal, could be the transition from conventional gas turbines to hybrid-electric drive trains. However, the requirements concerning weight and efficiency that come from applications like short range aircraft are significantly higher than what state-of-the-art technology can offer. A key technology that potentially allows to achieve the necessary power and volume densities for rotating electric machines is superconductivity. In this paper we present the concept of a high power density generator that matches the speed of typical airborne turbines in its power class. The design is based on studies that cover topology selection and further electromagnetic, HTS, thermal, structural and cryogenics aspects. All domains were analyzed by means of analytical sizing and 2D/3D FEA modeling. With the help of our digital twin that is a synthesis of these models, we can demonstrate for the first time that under realistic assumptions on material properties gravimetric power densities beyond 20 kW kg−1 can be achieved.

A Novel Single-Phase Tubular Permanent Magnet Linear Generator

A novel single phase tubular permanent magnet linear generator (TPMLG) for Stirling engines is proposed in this paper. It has an outer-stator, an inner-stator, a mover and a bread type winding which has no cutting. The mover consists of four ring-shaped permanent magnets, all of which are polarized radially. The polarization direction of the outer two permanent magnets is opposite to that of the inner two to form more magnetic circuits and achieve higher power generation density. The polarized directions of the two adjacent permanent magnets of both the outside and inside are opposite. The structure, dimensional parameters and operation characteristics of the generator are illustrated in detail. One of the structural advantages of this generator is that it is easy to control. The 3-D finite element (FE) model of proposed TPMLG is established. The model and its boundary conditions are presented and explained in detail. Through the FE model, its electromagnetic analysis is carried out. The performance of this generator under reciprocating frequency 75 Hz is investigated and analyzed. The simulation results show that the generator has the advantages of high power density.

High power density technologies for large generators and motors for marine applications with focus on electrical insulation challenges

High power density generators and motors are envisaged in modern all-electric ships where electrical power for both propulsion and service loads is provided through a common electrical platform known as an integrated power system. Three recent high-power density technologies for generators and motors proposed for marine applications are reviewed, and the author focuses on their electrical insulation challenges. These technologies are high-frequency (high-speed) generators (200–400 Hz), superconducting generators, and novel insulation materials and systems. For high-speed generators, high loss in magnetic materials may shorten its insulation life. Thus, these generators should be designed to be cooled by water instead of air. For superconducting generators, the most significant concern is the integrity of the insulation system over the large thermal excursion whenever the system is cycled between room temperature and operating temperature. In novel insulation materials and systems section: (i) using mica paper tapes containing boron nitride filler in the binding resin of the glass backing insulation, developed by Toshiba and Von Roll, resulted in a 15% increase in the MVA of generators for the same slot dimensions and operating temperatures, (ii) GE developed an enhanced polyethylene glycol terephthalate-mica tape having superior voltage-endurance characteristics, (iii) Isovolta has introduced a mica paper tape using a flat glass fibre backing material, called Powerfab, rather than the more common woven structure, leading to a 15% reduced mica tape, and (iv) adding novel nanocomposites as fillers to ground wall insulation, introduced by Siemens, is a promising technique towards more high power density designs. Furthermore, accelerated aging of insulation systems especially those in electrical rotating machines exposed to voltage pluses with high slew rates up to hundreds of kV/μs and high-repetition rates ranging from hundreds of kHz to MHz is discussed. These voltage pulses are generated by wide bandgap-based converters envisaged in the medium voltage DC architecture for future U.S. naval ships.

Novel trickling microbial fuel cells for electricity generation from wastewater

There are two main challenges associated with the scale-up of air-cathode microbial fuel cells (MFCs): performance reduction and cathode leakage/flooding. In this study, a novel 13.4 L reactor that contains 4 tubular MFCs was designed and operated in a trickling mode for 65 days under different conditions. The trickling water flow through the horizontally aligned MFCs alleviated the hydraulic pressure applied to the air-cathodes. With a total cathode working area of over 1700 cm2, this reactor generated power densities up to 1 W/m2 with coulombic efficiencies over 50% using acetate. Using a brewery waste stream as carbon source, an average power density of 0.27 W/m2 was generated with ∼60% COD removal at hydraulic retention time of 1.6 h. The decent performance of this reactor compared with other air-cathode MFCs at the similar scale and the alleviated hydraulic pressure on air-cathodes demonstrate the great potential of this design and operation for future MFC optimization and scaling up.

Modelling of PV systems installations using Geographical Information System:The case of Toluca (Mexico)

The goal of the paper is determining the available capacity of photovoltaic power generation density of a defined area through a modeling process using GIS. The method identifies the spots, and calculates the available area that receives solar radiation, taking into account geographical characteristics and spatial distribution of spots. Tilt and orientation are also considered to evaluate shading. The program identifies suitable spots valid for PV power generation. Power density is calculated from estimated values of available area and power, and data is corrected for horizontal plane that represents the reference for PV project evaluation. The method has the advantage of determining solar radiation and available area within high accuracy. The simulation results have been compared with the specific requirements for the configuration area, being within the established range, which proves the goodness of the method and verifies the availability of photovoltaic resources for the implementation of a power system. Keywords: ArcGIS, area sol, LIDAR maps, PV modeling, photovoltaic energy, power generation density

Improving the electrocatalytic activity for formic acid oxidation of bimetallic Ir–Zn nanoparticles decorated on graphene nanoplatelets

A graphene nanoplatelet (GNP)-supported Ir–Zn catalyst (Ir–Zn/GNP) was fabricated by H2 reduction to discover an alternative for non-platinum and non-palladium catalysts as an anode catalyst in direct formic acid fuel cell (DFAFC). The obtained Ir–Zn/GNP catalyst with ratio of Ir:Zn = 50:50 (Ir50Zn50/GNP) exhibited better electrocatalytic activity than GNP-supported iridium catalyst (Ir/GNP) for formic acid oxidation. Although the oxidation peak current density of Ir50Zn50/GNP was slightly lower than that of Ir/GNP, the oxidation peak potential shifted more negatively (193 mV) than Ir/GNP with higher value of the ratio of forward scan to reverse the scan peak current (If/Ib). The presence of Zn also enhanced the power density and current generation with increased performance stability in a passive DFAFC cell tests. The improvement of the electrochemical performance was ascribed to the ensemble effect where the addition of Zn could modify the Ir atom arrangement, thereby promoting the oxidation through dehydrogenation pathway. However, extremely high Zn content would inhibit oxidation capability because Zn atoms might reduce the Ir catalytic sites. A new alternative for non-Pt and non-Pd anode catalysts for DFAFC applications was successfully achieved.

Sensitivity Analysis and Design Optimization of a New Hybrid-Excited Dual-PM Generator With Relieving-DC-Saturation Structure for Stand-Alone Wind Power Generation

This article proposes a new hybrid-excited dual-permanent-magnet generator with the relieving-dc-saturation (RDCS) structure for stand-alone wind power generation. The proposed generator integrates the stator dc source and rotor permanent-magnet (PM) source in a single brushless structure, which enables coordinated power generation and flexible power adjustment. Moreover, considering the parasitic saturation effect in the stator core caused by the dc field source, a constant PM bias is introduced at the stator side to construct an RDCS structure, so that the core utilization ratio is improved as well as the generator power density. In this article, the generator structure and the operation principle are introduced. Some leading design parameters are determined based on the sensitivity analysis. A finite element and genetic algorithm combined method is further adopted to realize a multi-objective design optimization, and the optimal design of the proposed topology is verified to be a potential generator candidate for stand-alone wind power generation.

Photothermal Janus Anode with Photosynthesis‐Shielding Effect for Activating Low‐Temperature Biological Wastewater Treatment

AbstractBiological wastewater treatment (BWT), which is used to manage global wastewater, suffers from a sharp decrease in microbial activity at low temperature (&lt;10 °C). Photothermal technology with a high energy efficiency theoretically exceeding 80% has the potential to activate low‐temperature BWT. However, photothermal BWT is threatened by the propagation of photosynthetic algae in wastewater under irradiation, and these microorganisms can suppress the functional bacteria or even kill anaerobic species by photosynthetically releasing oxygen. Herein, taking microbial fuel cells (MFCs) as a representative biological reactor, a photothermal Janus anode (PTJA) is designed, composed of a carbon black/polydimethylsiloxane photothermal nonporous layer and a graphite felt porous layer to promote low‐temperature BWT. Unlike traditional symmetrical porous anodes, the nonporous layer of the PTJA can isolate the wastewater in the porous layer from light irradiation during photothermal conversion, thus preventing photosynthetic algae from poisoning anaerobic functional microbes. Under ≈1 sun illumination, the PTJA MFC exhibits 1.6 and 24.2 times higher organic pollutant removal rate and power density generation, respectively, than MFCs using traditional anodes for low‐temperature BWT (7.0 ± 2.0 °C). This development can allow novel utilization of solar energy and is a promising resolution for low‐temperature BWT.

Bio-inspired Nanocomposite Membranes for Osmotic Energy Harvesting

Summary Osmotic energy represents a widespread and reliable source of renewable energy with minimal daily variability. The key technological bottleneck for osmotic electricity is that membranes must combine highly efficient ion rectification and high ionic flux with long-term robustness in seawater. Here, we show that nanocomposite membranes with structural organization inspired by soft biological tissues with high mechanical and transport characteristics can address these problems. The layered membranes engineered with molecular-scale precision from aramid nanofibers and BN nanosheets simultaneously display high stiffness and tensile strength even when exposed to repeated pressure drops and salinity gradients. The total generated power density over large areas exceeded 0.6 W m−2 and was retained for as long as 20 cycles (200 h), demonstrating exceptional robustness. Furthermore, the membranes showed high performance in osmotic energy harvesting in unprecedentedly wide ranges of temperature (0°C–95°C) and pH (2.8–10.8) essential for the economic viability of osmotic energy generators.