Energy Benefits Research Articles

Ultralight lithiophilic three-dimensional lithium host for stable high-energy-density anode-free lithium metal batteries

Anode-free Li metal batteries (AF–LMBs) can exhibit substantially higher energy densities than that of Li-ion batteries (LIBs) and conventional LMBs; however, irreversible Li losses during Li plating/stripping, high density and low mechanical strength of state-of-the-art anode current collectors significantly undermine the energy benefits of AF configuration. Herein, we report Au-decorated insulating polyimide (PI@Au) nanofibers used as three-dimensional (3D) hosts promoting dendrite-free Li deposition. Their lithiophilic surfaces with low Li nucleation energy barrier and insulating 3D network with low local current density can synergistically regulate the uniform Li nucleation/growth following an “on fiber – in plane – on top” plating behavior. The superb Li reversibility ensures robust cycling stability of an NCM811||PI@Au AF–LMB cell with a high areal capacity of 6.4 mAh cm−2 (mass loading of 32.0 mg cm−2) for 100 cycles and high capacity retention of 86.0%. Owing to the ultrathin (10 μm) and ultralight (0.54 mg cm−2) characteristics of PI@Au nanofibers, unprecedented energy densities of 475 Wh kg−1 and 1199 Wh L−1 were achieved at the practical cell level, exceeding those of LIBs (263 Wh kg−1 and 634 Wh L−1) and LMBs (414 Wh kg−1 and 994 Wh L−1), respectively. The combination of a 3D insulating scaffold with lithiophilic decoration represents an effective strategy for designing AF–LMBs with ultrahigh energy densities.

A Nash bargaining model for energy sharing between micro-energy grids and energy storage

Micro-energy grids (MEGs) play a crucial role in achieving diverse energy utilization and promoting low-carbon economies. However, the intermittent nature of distributed generation and the inter-coupling of multiple energy types pose challenges to efficient energy management in MEGs. In this paper, we propose a novel Nash bargaining game-based electricity-gas energy-sharing model for MEGs. Our model incorporates bus structure-based energy storage combined with power-to-gas technology, which enables MEGs to establish an integrated electricity-gas energy-sharing network. This network facilitates both direct sharing and buffered sharing of energy, addressing the limitations of intermittent generation and enhancing overall energy management. To address the issue of computational complexity, the proposed Nash bargaining game model is decomposed into two sub-problems: social energy cost minimization and benefits sharing. Through optimization, we obtain optimal energy-sharing profiles and energy-sharing payments. Moreover, we consider the investment payback period of energy storage and adjust the initial benefit-sharing results accordingly. Case studies demonstrate that our model significantly improves economic performance, increasing the self-sufficiency ratio of MEGs to 64% and energy storage efficiency to 63% compared to operating independently. Additionally, the multiplayer Nash bargaining game model facilitates Pareto optimal benefits for MEGs and energy storage by capturing their interactive dynamics.

Theoretical Evaluation of Photovoltaic Thermal Water Source Heat Pump, Application Potential and Policy Implications: Evidence from Yangtze River Economic Belt, China

In the context of carbon neutrality, making full use of renewable energy is the key to further improve China’s development index. Within China’s Yangtze River Economic Belt, solar energy and river water, as clean and abundant sources of renewable energy, have garnered increasing. In this paper, a solar energy and surface water driven cogeneration system model is developed by TRNSYS to provide users with heat, cold and electricity. Six representative cities located along the upper, middle, and lower reaches of the Yangtze River Economic Belt were selected to evaluate and analyze the energy-saving, emission reducing, and economic and environmental benefits of solar energy and river water heat utilization in the aspects of energy, economy, and environment. The results shows that the annual power output of PV/T-GSHP system, from the west to the east of the Yangtze River, shows a phase growth trend, which is related to the light intensity. The annual heat output of PV/T plate gradually decreases from the lower reaches of the Yangtze River to the upper reaches. The research findings confirm the application potential of new energy sources in the Yangtze River Economic Belt and quantify the emission reduction effects of new environmental protection actions such as solar energy and river water heat sources. It provides valuable guidance for the utilization of new energy sources, including solar energy and surface water heat energy in the Yangtze River Economic Belt, as well as for optimizing energy policies.

Drilling Deeper in Shallow Geoexchange Heat Pump Systems—Thermogeological, Energy and Hydraulic Benefits and Restraints

In the last decade, due to climate change concerns and new environmental regulations in the EU, there was a tremendous rise in installed heat pump systems in new homes and buildings. The majority of these installed units are related to air-source heat pumps, as they offer a good trade-off between capital and operating expenses. However, when analysing heating and cooling heat pump systems from the primary energy consumption and ecological aspects, groundwater and shallow geothermal heat pump systems offer superior efficiency, compared to all market-available thermo-technical systems today. In the last decade, ground-source systems have seen some technological improvement by employing new borehole heat exchanger designs, such as piping with internal fins and a wider diameter (so called Turbocollector) to enhance the heat transfer between fluid and rock, as well as to reduce the pressure drop in the system. Furthermore, the process of drilling deeper offers higher ground temperatures and consequently higher seasonal performance factors in the heating cycle, due to the effect of the geothermal gradient. Nevertheless, although deeper boreholes provide better heat extraction rates per meter during the heat pump heating cycle, at the same time, it reduces heat rejection rates during the heat pump cooling cycle. The objective of this paper is to analyse and evaluate benefits and downsides of a new approach in the heat pump system design with deeper borehole heat exchangers of up to 300 m, comparing it to the traditional design of double-loop exchangers with 100 m depth. The geothermal borehole grid design simulation model, along with heat extraction and rejection, is performed on a yearly basis. The results are showing that the benefits of shallow geothermal boreholes, from the hydraulic and thermodynamic point of view, still dominate over deeper solutions.

Research on fair residential critical peak price: Based on a price penalty mechanism for high-electricity consumers

We construct a fair residential critical-peak price (CPP) optimization model based on a penalty mechanism to address the peaking pressure on the grid and the cost of new energy abandonment caused by the yearly increase in residential electricity load and the significant increase in new energy capacity. According to the electricity consumption habits of different residential consumers, we use the K-means clustering method to identify and classify high-electricity consumers (HECs), low-electricity consumers (LECs), and normal-electricity consumers (NECs) during the critical peak and valley load hours respectively, and design a penalty mechanism of electricity price for HECs (PMEP-H) that penalizes HECs during the critical peak load hours, and compensates the total penalty amount to LECs during the critical peak load hours and HECs during the valley load hours, then calculate the residential electricity load after implementation of PMEP-H based on consumer psychology. The CPP optimization model is constructed by considering the constraints of consumer satisfaction with electricity, tariff penalty, compensation balance, penalty and compensation price, power balance and new energy-generating units output power, and the objective function of high comprehensive system efficiency represented by the difference between peak cost of thermal generation, the benefit of new energy consumption and benefit of the grid side. The model is then solved using an improved particle swarm optimization algorithm for a real residential area in a populated area in northern China. The results show that the developed model can connect the generation, grid and user sides through the electricity consumption tariff, which generates considerable benefits in both peak cutting and new energy consumption targets and can enhance the comprehensive benefits of the generation, grid and user sides system to achieve the supply-grid-load linkage, providing a reference for the improvement of the CPP mechanism in China.

Experimental investigation on the operation performance of photovoltaic double skin façade in winter

Photovoltaic double skin façade (PV-DSF) offers a versatile solution to address the escalating energy demands of buildings by combining power generation and indoor air temperature adjustment functionalities. Most prior research concentrated on its summer performance, while the winter season receives less attention. This paper concentrates on its operation performance in winter, to provide an experimental framework for its efficient operation. In this regard, the performance of internal circle and thermal buffer mode (both are possible operation modes in winter) were compared via control variable experiments, and the feasibility of mechanical ventilation is also examined regarding the trade-off between the energy consumption of fans and additional energy benefit. These experiments were performed in the full-size experiment rig at Harbin, China, a city with severe cold climate. The experiment results conclusively demonstrate that the internal circle mode can outperform the thermal buffer mode on a cold, sunny day by 10.9%, and the total energy-saving potential can be further increased by 12.6% if fans are activated to enhance cavity airflow. While the experimental data during partly cloudy emphasizes the significance of a suitable operation schedule and shows that PV-DSF can only be switched to internal circle mode when cavity air is fully heated.

Retrofit heat exchanger network optimization via graph-theoretical approach: Pinch-bounded N-best solutions allows positional swapping

Retrofit heat exchanger network (HEN) optimization is a fundamentally unique problem which requires the consideration of existing structures, compared to grassroots design problems. The optimization of retrofit HENs is particularly difficult due to the integration of both existing and newly acquired equipment. The re-routing of existing equipment can lead to various network topologies, increasing the complexity of considerations. In this work, we exploit the P-graph framework to solve retrofit HEN problems, guaranteeing to find the topology of optimal solutions within the constrained space of the HEN retrofit problem. The P-graph framework has additional advantages that allows topologically-efficient search space, simplifies additional unit placement, considers unit positional swapping (re-sequencing and re-piping within search constraints), considers stream splitting, and n-best solution visualization. The pinch minimum utility constraint also provides a bound for the maximum number of modifications in the HEN, significantly reducing search space. The proposed P-graph-based approach is demonstrated using a real refinery case study to show its capability in obtaining the topology of the optimal HEN, highlighting the economic and energy benefits. Further extensions to other retrofit process integration problems (e.g. retrofit water network, hydrogen network etc.) will be enabled via the proposed P-graph approach.

Cooling Energy Benefits of Increased Green Infrastructure in Subtropical Urban Building Environments

Due to urban warming, the energy demand for cooling buildings is rising. The current study used CitySim (building energy model) to estimate the cooling energy requirements for 40 buildings in downtown Dubai using high-resolution climate data from weather research and forecasting (WRF) coupled with the single layer urban canopy model (SLUCM). Simulating the four mitigation scenarios allowed for the examination of the reduction in cooling load caused by the addition of greenery at a rate ranging from 25% to 100%. The insulated building’s cooling demand reduced by a maximum of 13.89% under 100% GI (M4). Scenario M4 resulted in a reduction of 4.6 kWh/m2 and 3.1 kWh/m2 for the non-insulated and insulated low-rise residential buildings, respectively, while the high-rise buildings saw a reduction of 3.09–4.91 kWh/m2 for the non-insulated and 2.07–3.09 kWh/m2 for the insulated buildings. This study offers a potential remedy to deal with the problem of urban heating in subtropical environments.

Multi-Angle Reliability Evaluation of Grid-Connected Wind Farms with Energy Storage Based on Latin Hypercube Important Sampling

Aiming to combat the problems of slow speed and poor accuracy of reliability evaluation of the power system in wind farms with energy storage, this paper proposes a method of reliability evaluation based on Latin hypercube important sampling (LHIS). Firstly, we aimed to establish the Latin hypercube important sampling evaluation model by combining the Latin hypercube sampling method with the important sampling method. Secondly, we aimed to optimize the sample probability distribution of the components and conduct hierarchical sampling of the system. Then, the comprehensive risk indicator (CRI) was proposed to evaluate the operational risk and the wind storage generation interrupted energy benefit (WSGIEB) was proposed to evaluate the contribution of the reliability. Finally, simulation experiments were carried out through various power system operation scenarios. The simulation results show that the proposed method is 47% higher than the improving importance sampling method (IM-IS) in evaluation speed and 33% higher than the improving importance sampling method in calculation accuracy.

An interval-based bi-level day-ahead scheduling strategy for active distribution networks in the presence of energy communities

The decarbonization of the electricity sector calls for new operational schemes and businesses. In this context, traditional consumers have evolved towards prosumers, enabling the active participation of domestic installations in the system operation. A set of prosumers can be organized into energy communities to unlock different economic and energy benefits. This paper develops a bi-level scheduling strategy for robust optimal operation of active distribution networks in the presence of energy communities. The new proposal deals with energy management in communities at the lower level while managing distributed assets at the upper level. The uncertainties in demand, renewable generation, and energy prices are modeled using interval notation, which allows to adopt pessimistic or optimistic strategies. In addition, a novel Stackelberg-bisection sub-module is advocated to determine the distribution system operator profit, which considers collective welfare. The developed Mixed-Integer-Linear programming framework is tested in the IEEE 33-bus network incorporating energy communities, passive consumers, and distributed assets. The results obtained serve to validate the new methodology as well as analyse different results. For example, it is observed that the adopted strategy directly impacts the monetary balance, thus varying the incomes by up to 28 % depending on the robustness level. The proposed Stackelberg-based sub-module is also analysed, indicating that the expected profit may vary by up to 3 % depending on the strategy adopted and the level of robustness assumed.

An empirical study of the risk-benefit perceptions between the nuclear and non-nuclear groups towards the nuclear power plant in Bangladesh

Public perception of benefit over risk is the de facto factor in planning, construction, operation, halting, or phase-out of a nuclear power plant in any country. Even if there are multiple pathways of perceiving risk/benefit among different stakeholders, the perception of nuclear and non-nuclear groups needs to be individually tracked to help understand sectoral influence. Related studies were basically performed between the STEM (Science, Technology, Engineering, and Mathematics) and non-STEM groups. However, there are no such studies between the nuclear and non-nuclear groups. This study investigated the risk-benefit perceptions between the nuclear group (N = 102) and the non-nuclear group (N = 467) using survey data to measure their stake and identify the underlying factors by validating the hypotheses, through descriptive analysis, and structural equation modeling (SEM). Results showed that risk perception is significantly high in the non-nuclear group (as the P-value is > 0.001 to <0.01) while the benefit perception is slightly low in the nuclear group (as the P-value is > 0.01 to <0.05). The non-nuclear group was significantly influenced by risk perception due to a lack of involvement in nuclear activities. Notably, the nuclear group is less interactive in disseminating nuclear energy benefits to the non-nuclear group. Surprisingly, misperceptions and lack of confidence about the benefits of nuclear energy also exist in the nuclear group. The study emphasizes debunking nuclear myths in the nuclear and non-nuclear groups through meaningful interactions and demands effective public awareness-building programs by competent authorities for the growth of the nuclear industry.

Simulation Models for Hydro-Electric Energy by Steady-Rate and Night-Shift-Pumped-Storage Operations

New operation simulation models for hydroelectric energy and its financial benefit over an N-year period in daily time steps by the steady-rate and the open-loop night-shift-pumped-storage rules are developed. These models are applied on 11 existing dams in Türkiye, which reflect a wide range of hydrologic and hydraulic peculiarities, for regulations between 90% through 40% and the outputs are compared. Regulation is the ratio of (outflow for energy generation, hm3/day) / (average inflow, hm3/day). The present worths of energy benefits and of pumping costs computed with a discount rate of 9.5% over a 35-year period yield that the night-shift pumped-storage operations are more profitable than the steady-rate rule. Finally, generalized regression equations for average annual produced energy and for present worth of net benefits by both operation rules against statistically significant explanatory variables are developed using the results of these 11 dams, which are all meaningful by relevant statistical criteria.

Trade-offs between water security and energy use: Lifecycle energy of water supply options in Paju, Korea

Despite net zero movement in Korea's water sector, comprehensive assessments of water-related energy in the region are lacking. Focusing on a water-stressed city with diversified water sourcing, this study evaluated both direct and indirect energy across the entire urban water cycle from abstraction to discharge and reclamation. By considering the energy embodied in pipelines and energy avoided from circular water use, this study compared the energy burdens and benefits of long-range piped water supply options (local supply and inter-basin import) and decentralized circular supply options (rainwater harvesting, greywater reuse, wastewater recycling, water loss reduction, water demand management). The results showed that conventional piped water supply options were still more energy-efficient than decentralized rainwater harvesting, greywater reuse, and some wastewater recycling options. In the case of Paju, advanced treatments required to provide high-quality industrial water made circular water options particularly less energy-efficient. The trade-offs between water security and energy use would be further strengthened in 2040, when the energy needs of the city's water supply increase by 27%. Expansion of the wastewater recycling would add 11% of the energy needs, whereas adoption of water-saving appliances in residential buildings decrease energy needs by 6%. For energy-efficient water management, Paju needs to consider adopting water demand management options, optimizing reclamation technologies and size, and harvesting renewable energy.

Collaborative communication and computational design for energy-efficient edge based learning network

In this paper, the potential for conserving energy has been used inside the collaborative network. The purpose of this work is to examine a model of a collaborative mobile cloud with the objective of lowering the total energy consumption of network nodes. This model is made up of many different network nodes, all of which collaborate with one another to build the network. We performed a theoretical examination into the quantity of energy that is used by the nodes when they are functioning as part of the network. In addition, a user grouping and scheduling-based system was established in order to establish when and how users should participate in the creation of the network. This was done so that the system could identify when and how users should contribute to the construction of the network. The proposed methodology took into consideration both the user and the base station components, and it made an effort to strike a balance between reducing the amount of energy that was consumed and ensuring that everyone was treated in an equitable manner. Even with higher delay values, the collaborative method may minimise energy use. The suggested approach uses slower but more energy-efficient nodes by increasing the allowable latency, which reduces energy usage and benefits from the diversity of nodes. The results of the simulation are presented by our proposed method from the perspective of user fairness as well as presenting the advantages of conserving energy that are associated with employing the collaborative strategy.

To pick (or not to pick) the high-hanging fruits: Cleaner production audits and firm total factor energy efficiency

The “low-hanging fruits” measures that easily and quickly reduced pollution and energy intensity over the past decades are now giving rise to issues. Cleaner production may provide new opportunities to gain the “high-hanging fruits”—more challenging or costly actions that have greater environmental and energy benefits but require advanced technologies or management for implementation. This study provides empirical evidence on the effects of cleaner production audits (CPAs) on Chinese manufacturing firms' total factor energy efficiency (TFEE), whose enhancement synergizes climate mitigation and green productivity growth. The study analyzes the effects of CPAs by employing a staggered difference-in-difference strategy combined with propensity score matching to compare samples of treated and untreated industrial firms for the period of 2000–2014. The findings show that regulated firms experience a 10.4% increase in TFEE. The contributions of green pure technical efficiency and green technical progress are 7.9% and 2.7%, respectively. Additionally, non-heavy polluters, small firms, and private firms demonstrate the greatest improvements in TFEE. However, CPAs do not significantly impact the TFEE of firms with high dependence on fossil energy. Finally, the mechanism analyses demonstrate that inner resource allocation optimization may be the main solution for improving TFEE by enhancing green pure technical efficiency. Green technological innovations in energy alternatives are the most promising paths for increasing TFEE by promoting green technical progress. These findings illuminate how manufacturing firms pick the “high-hanging fruits” of energy efficiency in more cost-effective ways and suggest useful insights for cleaner production promotion.

Analyzing the safety implications of the upsurge in domestic usage of liquefied petroleum gas (LPG) in Nigeria

The rapid rise in domestic Liquefied Petroleum Gas (LPG) usage in Nigeria signifies a transformative shift towards cleaner energy. This abstract encapsulates a thorough analysis delving into the safety implications linked to this transition. Through meticulous exploration of LPG usage, safety practices, regulations, and stakeholder perspectives, the study aims to illuminate multifaceted safety dimensions in Nigeria. Employing mixed methods, including surveys and interviews, the research offers a holistic view of LPG safety dynamics. Quantitative data of 200 households across the six geo-political zones indicates increasing LPG adoption, highlighting gaps in safety awareness and compliance. Qualitative insights shed light on challenges faced by users, experts, and regulators, providing a nuanced outlook on safety concerns and potential solutions. Key findings underscore the role of safety awareness in shaping user practices and the need for robust regulations for consistent safety enforcement. Stakeholder input emphasizes collaboration against counterfeit equipment and standardized safety training. Recommendations include targeted awareness campaigns, stronger regulations, and industry-user partnerships to bolster LPG safety. The research holds far-reaching implications for policies, industry practices, and public engagement. Amid Nigeria's pursuit of sustainable energy solutions, addressing safety implications of surging LPG usage becomes crucial. This abstract offers a glimpse into a comprehensive exploration aiming to contribute to a safer LPG landscape, harnessing cleaner energy benefits while prioritizing Nigerian households' well-being.

Towards Intergenerational Transfer to Raise Awareness about the Benefits and Co-Benefits of Energy Retrofits in Residential Buildings

The LES Project (LES-Llavor Energètica i Salut. Del cole a casa i a la societat, in English: Energy and Health Seed. From school to home and society) is seen as an opportunity to increase the visibility of the role of science and women scientists in their actual contexts and to present architectural research as essential in mitigating climate change and improving people’s health. The goal of this research was to reach the greatest range of people possible through intergenerational transfer. However, the main receptors and drivers were students aged between 8 and 10 years old who were responsible for transmitting energy and environmental conditioning concepts and their interrelations with strategic performance in buildings. Awareness was raised through scientific workshops implemented in primary schools that had energy and air quality deficiencies and opportunities, and the concepts were extrapolated to housing. Two schools in different socioeconomic districts (vulnerable and middle-income families) were selected as a strategy to provide details about the perceptions of energy benefits in both schools’ families. The results of the experience were highly satisfactory. Children from 8 to 10 years old were interested and ready to understand and transfer key concepts about energy efficiency and health improvement through the transformation of the buildings surrounding them. The dissemination of the project and social awareness reached the primary students of the two schools selected for the project and the entire educational community (students, teachers, families and all of society). Currently, we are working on a second stage that will allow for a broad volume of replicability of the workshops, with schoolteachers taking the lead in these actions. For this purpose, LES has the support of the Department of Education of the Generalitat de Catalunya.

Modeling and simulation of a micro gas-cooled nuclear reactor using Modelica

Highly compact micro nuclear reactors, which offer extensive energy benefits across ocean, land, space, and sky applications, have recently emerged as a popular research topic within the international nuclear industry. Due to its excellent inherent safety characteristics, the gas-cooled graphite-moderated reactor with TRISO fuel has attained extensive attention. Nonetheless, micro-reactors exhibit a high degree of system integration, characterized by the tight coupling and mutual constraints among various system functions. Conventional discipline-specific decoupled design patterns find it challenging to tackle the complexity arising from multi-disciplinary couplings. In response, this paper investigates the application of Modelica, a multi-domain unified modeling language, to construct models for several subsystems, encompassing the reactor, energy conversion system, and control system. This approach aims to enhance support for cross-disciplinary design. The accuracy of the reactor core model was verified by high-fidelity CFD simulation results, demonstrating a good agreement. Further investigations were then conducted on the safety and operational characteristics of the whole system. Typically, two simulations were conducted on the Gas cooled micro nuclear reactor (GCMR) design: one focused on an anticipated transients without scram accident scenario and the other on load-following operation. The simulation results demonstrated that the reactor possesses excellent inherent safety, even during extreme accidents. In such scenarios, the reactor is able to achieve shutdown solely through the negative reactivity resulting from increased core temperature. Furthermore, considering the heat accommodated in the reactor system and the constantly generated decay heat, a passive air-cooling mechanism has been investigated and successfully demonstrated with the model. The reactor also exhibits good load-following performance, which can be achieved by simply adjusting helium inventory (or pressure) and control drum position, while maintaining constant core temperature and power generation efficiency. These results can be leveraged to provide guidelines for further detailed designs of the GCMR.

Replacement Scenarios of LPG Boilers with Air-to-Water Heat Pumps for a Production Manufacturing Site

The replacement of LPG (liquefied petroleum gas) boilers with air-to-water heat pumps on an industrial site is proposed. The boilers are used to produce hot water for the heating of two workshops and for the manufacturing process (test benches). The substitution aims to improve the local air quality in terms of pollutant emissions. The energy benefits in terms of reduction of primary energy and CO2 emissions are analysed. The reduction in primary energy consumption varies between 51% and 64% for two different scenarios that are evaluated, respectively, under design and real operating conditions; the latter is based on the trend in heat loads and outdoor air temperatures recorded in a small town of central Italy in the year 2022. The results also show a decrease in CO2 production of between 58% and 68%. This replacement, carried out in a manufacturing context, represents a case study that may also be applied to industrial suburban areas of cities.

Porphyrins – Effective Photocatalysts for Red Light-Induced Functionalizations of Biomolecules

Recently, photoredox catalysis has begun to influence molecular biology and medical sciences for its mild conditions for generating highly reactive species (i.e., radicals), enabling novel and selective functionalisations of biomolecules.[1] In line with this, porphyrins, which can transfer energy (photosensitization) or electrons (photoredox catalysis) when exposure to light, seem to be highly advantageous. Given that their electron absorption shows a characteristic Soret band at 420 nm with a high molar extinction coefficient (105 M-1 cm-1),[2] they have been mainly used in blue-light-induced reactions. These molecules, however, absorb red light (four Q-bands at 518, 553, 592 and 648 nm with molar extinction coefficients of 104 M-1 cm), which has the benefit of low energy, lower health risks,[3] and more in-depth penetration of various media.[4] Fig. 1: Porphyrins in red lightinduced transformationsWe established that due to their diverse photophysical properties, porphyrins promote photoinduced electron transfer events under red light irradiation.[5] They act as effective photooxidants (alkylation of carbonyl compounds, thiol-ne reaction and reductive decarboxylation) and photoreductants (in arylation of heteroarenes, selenylation, thiolation and reduction of nitro compounds). These bioinspired photocatalysts exhibit features that outperform other catalysts operating under red light, as they are really non-toxic and can be applied in biological systems. Thus, we believe that free-radical porphyrins are a valuable contribution to the set of red-light photocatalysts, and this study will lead to more practical biosynthetic applications.