The development of novel materials with ion-selective nanochannels has introduced a new technology for harvesting salinity gradient (blue) energy, namely nanopore power generators (NPGs). In this study, we perform a comprehensive analysis of the practical performance of NPG in both coupon-size and module-scale operations. We show that although NPG membrane coupons can theoretically generate ultrahigh power density under ideal conditions, the resulting power density in practical operations at a coupon scale can hardly reach 10 W·m⁻² due to concentration polarization effects. For module-scale NPG operation, we estimate both the power density and specific extractable energy (i.e., extractable energy normalized by the total volume of the working solutions), and elucidate the impact of operating conditions on these two metrics based on the interplay between concentration polarization and extent of mixing of the high- and low-concentration solutions. Further, we develop a modeling framework to assess the viability of an NPG system. Our results demonstrate that, for NPG systems working with seawater and river water, the gross specific extractable energy by the NPG system is very low (~0.1 kW·h·m⁻³) and is further compromised by the parasitic energy consumptions in the system (notably, pumping of the seawater and river water solutions and their pretreatment). Overall, NPG systems produce very low net specific extractable energy (< 0.025 kW·h·m⁻³) and net power density (< 0.1 W·m⁻²). Our study highlights the significant practical limitations in NPG operations, casting doubt on the viability of NPG as a technology for blue energy harvesting.

具有离子选择性纳米通道的新型材料的开发引入了一种用于收集盐度梯度（蓝色）能量的新技术，即纳米孔发电机（NPG）。在这项研究中，我们对 NPG 在优惠券大小和模块规模操作中的实际性能进行了全面分析。我们表明，虽然 NPG 膜试片理论上可以在理想条件下产生超高的功率密度，但在试片规模的实际操作中产生的功率密度很难达到 10 W·m ^-2由于浓差极化效应。对于模块规模的 NPG 操作，我们估计功率密度和特定可提取能量（即，可提取能量由工作溶液的总体积归一化），并根据浓度之间的相互作用阐明操作条件对这两个指标的影响高浓度和低浓度溶液的极化和混合程度。此外，我们开发了一个建模框架来评估 NPG 系统的可行性。我们的结果表明，对于使用海水和河水的 NPG 系统，NPG 系统的总比可提取能量非常低（~0.1 kW·h·m ^-3) 并进一步受到系统中的寄生能源消耗的影响（特别是海水和河水溶液的泵送及其预处理）。总体而言，NPG 系统产生非常低的净比可提取能量（< 0.025 kW·h·m ^-3）和净功率密度（< 0.1 W·m ^-2）。我们的研究强调了 NPG 运营中的重大实际限制，对 NPG 作为蓝色能量收集技术的可行性提出了质疑。