Clean Technology by Design

Critics have opposed clean energy public investment by claiming that governments must not pick winners, green subsidies enable rent-seeking behaviour, and failed companies means failed policy. These arguments are problematic and should not determine the direction of energy investment policies.

Culture influences low-carbon energy transitions and as a result should be considered in the design of relevant policies. Focusing on a selection of low-carbon technologies and behavioural practices, this Review highlights the role of culture with respect to different dimensions of sustainability.

To withstand extreme weather, rapid innovation and rock-bottom prices, solar installations need tighter quality control, standards and testing.

Managing the interactions and impacts of scaled-up solar energy production will require understanding of the relationships between technological and ecological systems. This Perspective proposes a framework that could help engineer beneficial outcomes from an energy transition.

Capacity expansion modelling (CEM) approaches need to account for the value of energy storage in energy-system decarbonization. A new Review considers the representation of energy storage in the CEM literature and identifies approaches to overcome the challenges such approaches face when it comes to better informing policy and investment decisions.

Wind power faces numerous challenges as its role in energy systems expands, yet these are often largely seen as purely technical. This Review examines social science research connected to previously identified grand challenges in wind power and explores how a socio-technical lens can lead to improved outcomes for future wind projects.

The material-intensive transition to low-carbon energy will impose environmental and social burdens on local and regional communities. Demand-side strategies can help to achieve higher well-being at lower levels of energy or material use, and an interdisciplinary approach in future research is essential.

Aqueous zinc batteries are currently being explored as potential alternatives to non-aqueous lithium-ion batteries. In this comment, the authors highlight zinc’s global supply chain resilience and lower material costs yet caution about its higher mass requirement for comparable charge storage.

Tremendous research progress has been made in the development of post-lithium-ion batteries (PLIBs), yet there is little discussion on the manufacturing of these upcoming technologies. In this Review, the authors survey the current production status of several representative PLIBs and offer an industrial-scale manufacturing outlook.

Solid-state batteries are widely regarded as one of the next promising energy storage technologies. Here, Wolfgang Zeier and Juergen Janek review recent research directions and advances in the development of solid-state batteries and discuss ways to tackle the remaining challenges for commercialization.

The emergence of new materials and cell designs is enabling the transition of aqueous batteries into competitive candidates for reliable and affordable energy storage. This Review critically examines the scientific advances that have enabled such a transition and explores future research prospects.

Redox-active organic materials are a promising electrode material for next-generation batteries, owing to their potential cost-effectiveness and eco-friendliness. This Review compares the performance of redox-active organic materials from a practical viewpoint and discusses their potential in various post-lithium-ion-battery platforms.

In the field of lithium-based batteries, there is often a divide between academic research and industrial needs. Here, the authors present a view on applied research to help bridge academia and industry, focusing on metrics and challenges to be considered for the development of practical batteries.

Li–S batteries are a promising next-generation storage technology and the assessment of their performance is critical for their development. Here the authors analyse key Li–S cell parameters, formulate the energy density calculation and discuss design targets for practical applications.

Adoption of renewable energy sources will need to be accompanied by methods for energy storage. Lithium-ion batteries continue to dominate for portable electronic applications but other technologies are required for long-term and larger-scale storage. Redox flow batteries, the focus of this Review, represent one such technology.

The Review discusses the state-of-the-art polymer nanocomposites from three key aspects: dipole activity, breakdown resistance and heat tolerance for capacitive energy storage applications.

Reliability of stability data for perovskite solar cells is undermined by a lack of consistency in the test conditions and reporting. This Consensus Statement outlines practices for testing and reporting stability tailoring ISOS protocols for perovskite devices.

Metal halide perovskite (MHP) materials could revolutionize photovoltaic (PV) technology but sustainability issues need to be considered. Here the authors outline how MHP-PV modules could scale a sustainable supply chain.

An analysis of chemical processes to immobilize lead from perovskite solar cells is presented, highlighting the need for a standard lead-leakage test and mathematical model to reliably evaluate the potential environmental risk of perovskite optoelectronics.

Although perovskite solar cells now have competitive efficiencies compared with silicon solar cells, their low stability has hindered their commercial application thus far. This Review summarizes the tremendous improvements made over the past decade and offer a perspective on how to reach >25-year stable perovskite solar cells.

This Review discusses the current capabilities and challenges facing different power electronic technologies in wind generation systems from single turbines to the system level. Several projects are reviewed to highlight areas of current research focus, and future trends of wind power generation are summarized.

Efforts to find renewable alternatives to fossil fuels that might enable a carbon-neutral society by 2050 are described, as well as outlining a possible roadmap towards a refinery of the future and evaluating its requirements.

To achieve net-zero carbon emissions, we must close the carbon cycle for industries that are difficult to electrify. Developing the needed science to provide carbon alternatives and non-fossil carbon will accelerate advances towards defossilization.

Set up an international platform to share data and experiences, and coordinate industrial policies and trade to conserve resources and energy, urge Yong Geng, Joseph Sarkis and Raimund Bleischwitz.

Additive manufacturing is gaining growing attention as an alternative to conventional methods, but it can support more-sustainable manufacturing processes if developed through a system-level approach. This Perspective discusses how to achieve such a holistic development of additive manufacturing systems for sustainability.

The steel industry in China has an important role in reducing national and global carbon emissions, demanding integrated actions and efforts across policies, industry and science to achieve the goal of carbon neutrality.

It is possible — and crucial — to green the building blocks of the modern world.

Concrete is one of the most widely used man-made materials and is critical for the ongoing urbanization of the global population. However, owing to its widespread use, concrete can have a negative impact on the environment. This Review provides medium-term and long-term solutions to address the environmental concerns surrounding concrete production.

The textile industry is energy intensive and releases huge amounts of pollutants to the environment. Here the authors take a life cycle approach to examine the technological progress made to improve the sustainability of each stage and propose the future directions.

Four future greenhouse gas emission scenarios for the global plastics system are investigated, with the lead scenario achieving net-zero emissions, and a series of  technical, legal and economic interventions recommended.

Biomass and plastic share structural similarities in their composition and types of bond linkage between their monomeric units. Reviewing their catalytic conversion technologies in a unified angle provides new insights and opportunities for future advances.

Catalytic pyrolysis is a promising process for the valorization of biomass and plastic waste, although several aspects related to its practical utilization remain unexplored. This Perspective revisits the salient features of catalytic pyrolysis, identifying a roadmap to advance the application of this technology at commercial scale.

This Review introduces solar reforming as an emerging technology to produce sustainable fuels and chemicals from diverse waste feedstocks using sunlight. The chemistry and concept of solar reforming, suggestions of key metrics and proposed directions to realize solar-powered refineries for a future circular economy are discussed.

Green production of hydrogen peroxide (H₂O₂) with a sunlight-driven or renewable-energy-powered electrochemical process provides a path to its decentralized production and sustainable end-use. Here, we discuss how to develop a fairer basis for performance evaluation of (photo)electrosynthesis of H₂O₂.

Suzanne Zamany Andersen, future founding CEO of Nitrofix Solutions, talks to Nature Synthesis about lithium-mediated ammonia synthesis and a career path through academia and beyond.

Green ammonia will play an important function in decarbonized energy systems but its production places a high burden on limited renewable resources in land-constrained countries. Here we propose the offshore production of green ammonia, which can increase energy security without land competition.

Electrocatalytic NO_x reduction (NO_xR) to ammonia has recently become an increasingly popular alternative to the more challenging N₂ reduction. This Perspective critically assesses the possible ways NO_xR could contribute to the ammonia economy and clarifies the necessary steps for a rigorous experimental protocol.

Heat pumps are widely recognized as a key clean energy technology in the energy transition. While the global heat pump market has expanded significantly, more than doubling in some countries in a single year, expanded policy support will be needed to build confidence in the technology and meet climate goals.

Demand for cooling is expected to increase globally. To deliver sustainable cooling beyond energy-intensive technological solutions, a comprehensive analytical framework and research agenda are proposed.

Earth’s oceans are awash with ageing energy infrastructure. A change in the law is needed to ensure that these structures are decommissioned in ways that maximize environmental and societal benefits.

The complexity of the infrastructure underpinning the modern Internet has led to a lack of clarity on how to measure the energy consumption of web services and achieve sustainable web design. It is now crucial to redirect sustainability efforts in the sector towards more effective interventions.

Fuel cells are increasingly being considered for powertrains of heavy-duty transportation. Cullen et al. survey the technical challenges of fuel cells at both the system and materials level for transportation application and outline the roadmap for future development.

As road transport emissions are set to grow, stronger policy mixes are needed to reach mitigation goals. This Perspective considers the evidence for several policy types—strong regulation, pricing and reduced travel—and the best combination to reduce emissions for passenger and freight vehicles.

The economic, technical, environmental and safety requirements of battery-powered aircraft are considered, and promising technologies and future prospects for battery innovation are discussed.

Solid-state electronic components that control and convert electrical power are key to the energy management and lifetime of electrified transport.

Hydrogen, which possesses the highest gravimetric energy density of any energy carrier, is attractive for both mobile and stationary power, but its low volumetric energy density poses major storage and transport challenges. This Perspective delineates potential use cases and defines the challenges facing the development of materials for efficient hydrogen storage.

This Review presents an overview and analysis of biomimetic engineering principles and strategies for developing unique surface properties to design all-weather, portable water harvesting systems. It discusses key processes involved in water harvesting and proposes a framework for designing next-generation sustainable systems to alleviate freshwater scarcity.

Solar desalination has the potential to contribute to the solutions regarding global water scarcity. This Review discusses the road and challenges towards the industrialization of solar desalination plants.

The wastewater treatment industry contributes approximately 1.6% of greenhouse gas emissions. This Review analyses alternative wastewater treatment pathways for simultaneous CO₂ capture and utilization and shows the multiple benefits of microbial electrochemical and phototrophic processes.

Efficiency is only one of the parameters involved in solar evaporation that should be improved to make it practical. Depending on the application, various factors of merit should be taken into consideration, as discussed in this Perspective.

Production of hydrogen fuel by electrolysis of low-grade or saline water, as opposed to pure water, could have benefits in terms of resource availability and cost. This Review examines the challenges of this approach and how they can be addressed through catalyst and electrolyser design.

Recovering metals from wastewater and brine could augment metal stocks that are fundamental to modern technology. This Perspective assesses the potential of, and provides guidance for, recovering metals from wastewater and brine.

Using carbon dioxide capture and storage (CCS) for carbon removal is crucial to climate policy, but implementation at scale is at risk owing to political obstacles. Climate policies must avoid relying on empty promises of CCS for carbon removal without necessary financial resourcing and support emissions reductions separately from carbon removal.

Various methods of carbon dioxide removal (CDR) are being pursued in response to the climate crisis, but they are mostly not proven at scale. Climate experts are divided over whether CDR is a necessary requirement or a dangerous distraction from limiting emissions. In this Viewpoint, six experts offer their views on the CDR debate.

Given the escalating climate crisis, the task of integrating novel carbon dioxide removals into the European Union’s climate policy is urgent and long overdue. This Comment argues that there is a window of opportunity for responding now, and puts forward a solution.

Renewable electricity-powered CO₂ electroreduction offers a sustainable route to transform the chemical industry. Here the authors overview four CO₂ electrolysis pathways that could be immune from carbonate formation, a major technological barrier.

CO₂ electroreduction aims to decarbonize converting CO₂ and clean energy into chemicals. To have an impact, this technology should be scaled up into the gigatonne conversion range. In this Review, the authors analyse challenges related to resource and material scalability bottlenecks to enable the sustainable deployment of CO₂ electroreduction.

This Perspective discusses electrochemically mediated carbon dioxide capture systems, which can offer lower energetics than standard thermal methods, with modular scalability. New integrated configurations can further reduce costs and improve unit productivity, while further engineering of existing cell designs will enable more rapid implementation.

Tandem catalysis and tandem reactors provide unique opportunities for sustainably converting CO₂ into valuable products that are not accessible by traditional catalytic processes. This Perspective discusses progress in and opportunities for developing tandem catalytic process that involve various combinations of thermocatalysis, electrocatalysis, photocatalysis, plasma catalysis and biocatalysis.

Progress in the field of photocatalytic CO₂ reduction has been constrained by a lack of comparability between studies. This Perspective provides recommendations for best practices in the undertaking and reporting of experimental data in this promising research area.

Direct CO₂-to-C₂₊ and tandem CO₂-to-CO and CO-to-C₂₊ electrocatalytic systems have been proposed as strategies for sustainable fuel and chemical synthesis. This Perspective considers the role of acidic CO₂ gas on the cathodic microenvironment and local pH and draws connections between this and product selectivity in the electrochemical CO₂ reduction reaction and the electrochemical CO reduction reaction, focusing on the competition between two major pathways: ethylene/ethanol and acetate.

Water management is crucial for enhancing economic viability and minimizing the environmental impact of direct air capture (DAC) technologies, but the high energy intensity necessitates heat recovery techniques. This Perspective discusses several front-end and back-end strategies for coupling water management with heat integration in DAC processes.

This Review makes the case for enhancing indoor air quality through indoor CO₂ capture and describes how technological advances in materials and chemistry enabled these improvements. New constructions or retrofitting buildings would allow these advances to be implemented to improve CO₂ capture.