Carbon-free Electricity Research Articles

Major US electric utility climate pledges have the potential to collectively reduce power sector emissions by one-third

Major US electric utility climate pledges have the potential to collectively reduce power sector emissions by one-third

Are electric vehicles getting too big and heavy? Modelling future vehicle journeying demand on a decarbonized US electricity grid

In the US a complete transition to electric vehicles (EVs) would increase demand for carbon-free electricity by around 30% if the future fleet has the same average size, weight and horsepower as current EVs. However, these dimensions for today's EVs are substantially lower than for conventional vehicles, so as EVs replace them, EV's average size, weight and horsepower are likely to increase substantially. Further, major automakers are introducing a new class of very large, powerful “super”-EVs of up to 1000 horsepower. These factors will lead to higher demand for carbon-free electricity. This interdisciplinary paper first examines the social pressure for increasing EV size and power. It then uses data from the 255 EVs tested by the US EPA in 2011–2021, to estimate the effect of increased weight and horsepower on EVs' electricity consumption. It finds that each 1% increase in weight leads to an increase in electricity consumption of about 1%. The transition to EVs could therefore increase electricity consumption by 35% or more and compromise the transition to a decarbonized electricity grid. Policymakers need to plan for a larger decarbonised grid, disincentivise production of large, heavy EVs and promote positive social discourse on the value of smaller, lighter vehicles.

Quantitative methodology for the estimation of the environmental impact of wind farms – The case of Greece and application on the country’s operating units

Following the EU guidelines towards a carbon free electricity sector by 2050, wind energy is expected to contribute a large part of the produced electricity, if not the largest. In this respect, wind installations are expected to multiply over the next years. There is significant development until today and wind is generally considered as a “clean” source of energy. However, although arguably less than other sources, the impacts concerning wind installations are certainly there amidst ever-growing local opposition and will certainly grow, especially in locations with high density. Attempting to quantify the total impacts per local regions in the case of Greece, a methodology is developed for those impact factors that are considered the most important. Certain focus areas are used for applying this methodology, based on installation density, location inside natural protected areas, as well as locations of touristic value. The results show that in general the total impacts might be considered on average mild to low. The tool developed is a first attempt to evaluate impact in a cumulative way and help investors, policy makers and local communities work together in achieving the best possible outcome. Further work is necessary to further develop this methodology, verify and detail the formulas used and establish a robust pattern that will be a useful tool for everyone to use.

(Invited) Carbon Capture and Utilization Research at the National Energy Technology Laboratory (NETL)

This talk will describe NETL’s ongoing research efforts in the areas of carbon capture and utilization, with a focus on materials design and in situ characterization to understand the system under working conditions. A brief overview will be given on NETL-developed sorbents and membranes that can capture/separate CO2 emissions from industrially-relevant streams. Once captured, the CO2 can be chemically converted into gaseous or liquid chemicals for down-stream upgrading into industrially relevant chemicals. A key requirement is the ability to utilize excess, carbon-free electricity and operate intermittently, and NETL has developed several electrically-driven reaction schemes. We have developed copper electrocatalysts that selectively convert CO2 and water into syngas (CO + H2) without the need for expensive metals, such as silver or gold. The syngas can then be upgraded into a variety of chemicals using current industrial processes. Converting CO2 into liquid products is also attractive due to advantages associated with easier storage and transport. Formic acid (formate) is one candidate with current agricultural and industrial uses, and it is also an emerging liquid hydrogen carrier. We have demonstrated unique three-dimensionally-structured tin oxide catalysts that convert CO2 into formate with high current densities (~500 mA/cm2) and good Faradaic efficiencies (~70% FE). Electrocatalyst efforts have also developed surface-science approaches to study precious metal-free catalysts to replace traditional IrO2 used in electrolyzer anodes, which will reduce precious metal requirement and lower the overall system cost. Finally, we will discuss emerging microwave-based catalyst systems that convert CO2 and CH4 into syngas with energy efficiencies that approach or exceed state-of-the-art electrochemical CO2 reduction and water splitting technologies.

(Invited) Electrochemical Recycling of Used Nuclear Fuel

Current nuclear energy systems produce approximately twenty percent of the electricity generated in the U.S. and account for approximately fifty-five percent of the carbon-free electricity. As the U.S. strives for even lower carbon emissions such as net-zero carbon emission by 2050, nuclear energy will play an increased role in providing baseload electricity to the nation. An opportunity to implement advanced reactor and fuel cycle technologies that offer enhanced resource utilization, waste management and non-proliferation features will be available as the role of nuclear energy expands to meet the growing demand of carbon-free electricity. For example, the U.S. can transition from the current once-through fuel cycle to a closed fuel cycle with used fuel recycling that provides actinides for energy production and encapsulates fission product waste in durable, engineered waste forms.Argonne National Laboratory has a rich-history in developing new methods to recycle used nuclear fuels that dates back to the late 1950s. This early work focused on developing methods to recycle the actinides extracted from used nuclear fuel and closing the nuclear fuel cycle. Early techniques consisted of melting the used metallic fuel discharged from the Experimental Breeder Reactor II in lime-stabilized zirconia crucibles to produce a liquid uranium alloy that could be separated from the resulting oxide dross containing the fission product elements. The resulting uranium alloy was recycled to produce fresh nuclear fuel. Subsequently, more elegant techniques such as molten salt – liquid metal extraction processes were developed to recover and recycle the actinides present in the oxide dross, and to separate the actinides from the fission product elements present in used metallic fuel. In both cases, the actinides were recycled in fresh nuclear fuel and the fission products were sequestered in waste forms.Argonne’s research and development efforts in used fuel recycling expanded to include areas such as oxide to metal conversion via chemical reduction in a molten salt flux and developing new processes for recycling the actinides extracted from nitride and carbide fuels. Work in this area evolved to include the design and development of electrochemical technologies for recovering actinide metals from used nuclear fuels and an electrolytic reduction process for the conversion of metal oxides to metallic forms.The transition of used nuclear fuel processing from chemical to electrochemical methods established the need for fundamental electrochemical data for the actinide and fission product elements in molten salt media, provided opportunities for the design and demonstration of purpose-built electrochemical processing equipment, and allowed for the use of process monitoring and control technologies to enable efficient electrochemical cell operations. Actinide metal nucleation and growth in a molten LiCl - KCl eutectic salt is an example of the type of fundamental data that has been collected to elucidate the behavior of actinides during the electrodeposition process. Results from those experiments revealed that actinide nucleation transitions from progressive to instantaneous growth with increasing actinide chloride concentration in the molten salt. This behavior influenced the design of electrochemical processing equipment. Other data such as actinide ion diffusion coefficients were also determined from the experiments.Electroanalytical process monitoring and control techniques are being developed for several molten salt applications. These techniques are ideally suited for molten salt applications due to the specificity of chemistry information that is produced, simplicity of equipment design, and functionality at elevated temperature and in radiation environments. Argonne developed a multi-function sensor and methodology that yields reproducible electrochemical data such as the redox potential of the salt and the identities of species present in the system for applications in used fuel processing and monitoring heat transfer fluids.Argonne’s molten salt activities span the range from fundamental property measurement to pilot-scale process demonstrations. The presentation will provide a survey of Argonne’s electrochemical fuel recycling activities including actinide electrochemistry, process design and development, and electroanalytical sensor development.ACKNOWLEDGMENTS: The submitted abstract has been created by UChicago Argonne, LLC, Operator of Argonne National Laboratory (“Argonne”). Argonne, a U.S. Department of Energy Office of Science laboratory, is operated under Contract No. DE-AC02-06CH11357. The U.S. Government retains for itself, and others acting on its behalf, a paid-up nonexclusive, irrevocable worldwide license in said article to reproduce, prepare derivative works, distribute copies to the public, and perform publicly and display publicly, by or on behalf of the Government.

The Carbon Value of Nuclear Power Plant Lifetime Extensions in the United States

Nuclear power is currently the single largest carbon-free source of electricity in the United States. The climate mitigation cost savings of the existing U.S. nuclear fleet is denominated in hundreds of billions of dollars [net present value (NPV)] based on an integrated assessment modeling of the U.S. energy system within a globally consistent framework. Lifetime extensions of the existing nuclear fleet from 40 years to 60 and 100 years resulted in $330 billion to $500 billion (all figures are in U.S. dollars) (NPV) of mitigation cost savings for the United States under a deep decarbonization scenario consistent with limiting global temperature change to 2°C. The addition of new nuclear deployments in the United States increased the total U.S. mitigation cost savings of the 2°C climate goal by up to $750 billion (NPV). Immediate actions are required in the United States and globally to achieve net-zero carbon emissions by mid-century, and once achieving net-zero emissions, they must remain at net-zero indefinitely. Lifetime extensions of the existing nuclear fleet, in the United States and globally, support urgent near-term emissions reduction goals. Additionally, the longevity of nuclear power technologies reduces the need for new capacity additions of all carbon-free electricity sources and supports long-term actions necessary to maintain net-zero emissions.

Could clean industrial progresses and the rise of electricity demand foster the penetration of nuclear fusion in the European energy mix?

The effects of the update of the EUROfusion TIMES Model (ETM) industrial sector to account for the introduction of low-carbon technologies is presented and discussed in this work. ETM is a minimum-cost energy system model aimed at investigating the conditions for the introduction of nuclear fusion in the future electricity mix. The most interesting ETM long-run scenarios (until 2100) must comply with stringent environmental targets to pursue the Below-2-Degrees objective, identified in the Paris Agreement, allowing wide commercial adoption of innovative production processes - currently under test or research - which would almost completely replace well-established fossil-based industrial techniques in the iron and steel, chemicals, non-ferrous metals, non-metallic minerals and pulp and paper sub-sectors. Among them, low-carbon and electrolysis-based processes could open the way to a considerable increase of electricity demand, requiring also clean resources not to undermine sectoral efforts in becoming more environmentally sustainable, and the same does the implementation of CCS technologies. The study shows that the industrial sector contributes to the energy mix decarbonization by relying on CCS technologies, when available, or new low-carbon technologies. The progressive electrification of the industrial sector turns into an increasing final electricity demand which is covered by renewables and nuclear when stringent climate policies are put in place. Despite technological constraints are likely to slow down fusion deployment in the future, a range of scenarios show that nuclear fusion could contribute to generation of carbon-free electricity in the future European energy system.

Economic solution for low carbon process heat: A horizontal, compact high temperature gas reactor

In 2018, nuclear energy generated 55% of United States’ and one third of the world’s carbon free electricity, making nuclear energy a key tool in efforts to mitigate climate change before 2050. However, the current nuclear technology, light water reactors (LWRs), is limited to 300°C, so it cannot be used to decarbonize industrial process heat which accounts for 12% of US greenhouse gas emissions. High temperature gas reactors (HTGRs) can meet the high temperature demand with carbon free nuclear heat. The estimated cost of HTGRs, such as the Next Generation Nuclear Plant (NGNP), are even higher than state-of-the-art LWRs. In this paper, we expanded our nuclear cost estimating tool to include HTGRs and find that the NGNP overnight capital costs were 32% higher than an advanced LWR per unit capacity. The higher cost will naturally result in larger risk to cost overrun as recently experienced by larger LWRs in western nations. With a design-to-build mindset to minimize cost and construction risk, we introduce the horizontal, compact HTGR (HC-HTGR). The reactor core and steam generator are mounted horizontally on rails and in-line with one another, decreasing the size of the reactor building relative to the power capacity four times when compared to traditional HTGRs. The HC-HTGR reduced overnight civil structure costs by 42%, indirect costs by 38%, and total capital costs by 20% from NGNP. We discussed the required engineering of new systems for the HC-HTGR including vessel supports, the reactor cavity cooling system, and steam generator design. Finally, we estimated the fuel and operations costs of the HC-HTGR, and a survey of low-carbon industrial process heat technology showed the HC-HTGR can deliver a highly competitive levelized cost of heat in the range of $6.13–12.48/GJ.

Methodology and Application of Statistical Techniques to Evaluate the Reliability of Electrical Systems Based on the Use of High Variability Generation Sources

This study presents a new methodology, based on Monte-Carlo techniques to evaluate the reliability of a carbon-free electricity generation system based on renewable sources; it uses as inputs the variation of the electricity demand and the fluctuations in the renewable supply and provides the renewable system to be installed to guarantee a specific supply reliability level. Additionally, looking for a reduction of this renewable system, the methodology determines the improvements by the incorporation of nuclear power and electricity storage. The methodology is of general application, its implementation being possible under different contexts, such as different time horizons and different future energy scenarios, both for developing, emerging, and developed countries. The only requirement is to have a sufficient database from which to make predictions for future scenarios of electrical generation–demand balances. As an example of practical implementation, the electrical system reliability for the particular case of Spain in 2040 has been forecasted. When considering the fluctuations in solar and wind power contributions, very high values of the installed power from these renewable sources are needed to reach a high reliability of the system. These values decrease substantially if contributions from nuclear and storage technologies are included.

A cost-minimizing approach to eliminating the primary sources of greenhouse gas emissions at institutions of higher education

PurposeMany institutions of higher education have committed to carbon neutrality. Given this goal, the main economic issue is minimizing cost. As for society as a whole, dominant decarbonization strategies are renewable electricity generation, electrification of end uses and energy efficiency. The purpose of this paper is to describe the optimum combination of strategies.Design/methodology/approachThere are four questions for eliminating the primary institutional greenhouse gas emissions: how much renewable electricity to produce on-site; where and at what price to purchase the balance of renewable electricity required; how to heat and cool buildings without fossil fuels; and how much to invest in energy efficiency. A method is presented to minimize decarbonization costs by equating marginal costs of the alternates.FindingsThe estimated cost of grid-purchased carbon-free energy is the most important benchmark, determining both the optimal level of campus-produced renewable energy and the optimum efficiency investment. In the context of complete decarbonization, greater efficiency investments may be justified than when individual measures are judged only by fossil-fuel savings.Practical implicationsThis paper discusses a theoretically ideal plan and implementation issues such as purchasing carbon-free electricity, calculating marginal costs of conserved energy, nonmarginal cost changes, uncertainty about achieving efficiency targets, and dynamic pricing. The principles described in this study can be used to craft a cost-minimizing decarbonization strategy.Originality/valueWhile previous studies discuss decarbonization strategies, there is little economic guidance on which strategies are optimal, on how to combine strategies to minimize cost or how to identify a preferred path to decarbonization.

Techno-Economic Assessment of Battery Electric Trains and Recharging Infrastructure Alternatives Integrating Adjacent Renewable Energy Sources

Battery electric multiple units (BEMU) are an effective path towards a decarbonized regional rail transport on partly electrified rail lines. As a means of sector coupling, the BEMU recharging energy demand provided through overhead line islands can be covered from decentralized renewable energy sources (RES). Thus, fully carbon-free electricity for rail transport purposes can be obtained. In this study, we analyze cost reduction potentials of efficient recharging infrastructure positioning and the feasibility of covering BEMU energy demand by direct-use of locally produced renewable electricity. Therefore, we set up a model-based approach which assesses relevant lifecycle costs (LCC) of different trackside electrification alternatives comparing energy supply from local RES and grid consumption. The model-based approach is applied to the example of a German regional rail line. In the case of an overhead line island, the direct-use of electricity from adjacent wind power plants with on-site battery storage results in relevant LCC of EUR 173.4 M/30a, while grid consumption results in EUR 176.2 M/30a whereas full electrification results in EUR 224.5 M/30a. Depending on site-specific factors such as existing electrification and line lengths, BEMU operation and partial overhead line extension can lead to significant cost reductions of recharging infrastructure as compared to full electrification.

Bimetallic effects on Zn-Cu electrocatalysts enhance activity and selectivity for the conversion of CO2 to CO

We report an active zinc-copper (Zn-Cu) bimetallic electrocatalyst for CO 2 reduction to CO, prepared by a facile galvanic procedure. Under moderate overpotentials, Zn-Cu catalysts that are Zn rich exhibit intrinsic activity for CO formation superior to that of pure Zn, Cu, and Ag, the last of which is the state-of-the-art catalyst in CO 2 electrolyzers. Combinatorial experiments involving catalysts prepared by physical vapor deposition reveal trends across the Zn-Cu system, corroborating the high CO selectivity unrivaled by other alloys and intermetallics. Physical and electrochemical characterization and first principles theory reveal that the origin of this synergy in intrinsic activity is an electronic effect from bimetallic Zn-Cu sites that stabilizes the carboxyl intermediate during CO 2 reduction to CO. Furthermore, by integrating Zn-Cu into gas-diffusion electrodes, we demonstrate that bimetallic effects lead to improved electrocatalytic performance at industrially relevant currents. These insights provide catalyst design principles that can guide future development of efficient and earth-abundant CO-producing electrocatalysts. • A Zn-Cu electrocatalyst is prepared by a facile galvanic-exchange synthesis procedure • Zn-Cu electrodes demonstrate high selectivity (>95%) for CO 2 reduction to CO • Bimetallic effects stabilize the carboxyl intermediate during the CO 2 reduction Electrochemical CO 2 reduction is a promising strategy for the sustainable synthesis of fuels and chemicals when combined with carbon-free electricity. A major challenge for the development of electrochemical CO 2 reduction has been establishing robust design principles that can guide the discovery of cost-effective catalysts, due to the complexity of the reaction networks. In this work, we discover a bimetallic effect between Zn and Cu that promotes synergistic performance for CO 2 reduction to CO superior to that of its pure component metals. The insights and catalyst structure-property relationships obtained can guide the future development of efficient and earth-abundant electrocatalysts for CO 2 reduction. We achieve a >7-fold enhancement in intrinsic activity for electrochemical CO 2 reduction relative to a Zn-based electrode, by simply introducing a small quantity of Cu atoms onto the Zn surface. Detailed mechanistic investigations reveal that this improvement originates from a bimetallic effect between Zn and Cu, which can stabilize the key carboxyl intermediate during the CO 2 reduction to CO.

Conditional Yardstick Competition in Energy Regulation

Electricity production is a key sector in global decarbonization efforts, and variable renewable energy (VRE) technologies are a primary way to produce carbon-free electricity. We study an electricity market where generation is 100 %VRE, while storage and elastic demand resolve temporal supply-demand imbalances. We model hourly market equilibrium to analyze price formation and imperfect, Cournot-type competition with varying levels of ownership concentration.Market power is exerted either with storage-only or with both VRE and storage.In such a system, prices are determined dynamically by demand and intertemporal storage decisions, breaking the static logic of “merit order” with dispatch-able generation. The numerical results indicate that market power with storage has a relatively moderate effect on prices and market efficiency. However, market power exerted with VRE has far larger welfare impacts, resulting from curtailed generation. However, such actions could be more readily observed by a regulator via monitoring.

Pricing and Competition with 100% Variable Renewable Energy and Storage

Electricity production is a key sector in global decarbonization efforts, and variable renewable energy (VRE) technologies are a primary way to produce carbon-free electricity. We study an electricity market where generation is 100 %VRE, while storage and elastic demand resolve temporal supply-demand imbalances. We model hourly market equilibrium to analyze price formation and imperfect, Cournot-type competition with varying levels of ownership concentration.Market power is exerted either with storage-only or with both VRE and storage.In such a system, prices are determined dynamically by demand and intertemporal storage decisions, breaking the static logic of “merit order” with dispatch-able generation. The numerical results indicate that market power with storage has a relatively moderate effect on prices and market efficiency. However, market power exerted with VRE has far larger welfare impacts, resulting from curtailed generation. However, such actions could be more readily observed by a regulator via monitoring.

Use of Distributed Electricity Generation Technologies in Hotels

Distributed electricity generation technologies have increasing applications worldwide in various sectors due to their environmental and economic benefits. In the present study the use of these technologies in hotel industry is investigated. Various distributed electricity technologies, including co-generation of heat and power systems, are examined. Some of them are using renewable energies like solar energy, wind energy and biomass for electricity generation. Others are related with various co-generation systems including fuel cells. Many hotels require almost equal amounts of heat and electricity in their daily operations. Co-generation technologies have the advantage that they can cover almost all of their requirements in both electricity and heat. Some distributed electricity generation technologies including solar photovoltaic energy, co-generation systems, wind turbines and fuel cells are already used in hotels. Their energy efficiency varies in the range of 10% to 90%. Technologies using renewable energies generate carbon-free electricity while others fueled by natural gas generate electricity with low carbon impacts. Each technology has advantages and drawbacks while the possibility of using each technology depends on hotel’s characteristics as well as on the local availability of renewable energy sources. The results of the present study are important in hotel industry since they indicate the possibility of using the environmentally friendly distributed electricity generation technologies for covering their electricity as well as, in some cases, their heating requirements reducing their carbon footprint due to energy use and increasing their energy and environmental sustainability.

Integration of Photovoltaic Electricity with Shallow Geothermal Systems for Residential Microgrids: Proof of Concept and Techno-Economic Analysis with RES2GEO Model

The European Union aims to reduce Greenhouse Gas (GHG) emissions by 55% before 2030 compared to 1990 as a reference year. One of the main contributions to GHG emissions comes from the household sector. This paper shows that the household sector, when organised into a form of prosumer microgrids, including renewable sources for electric, heating and cooling energy supply, can be efficiently decarbonised. This paper investigates one hypothetical prosumer microgrid with the model RES2GEO (Renewable Energy Sources to Geothermal). The aim is to integrate a carbon-free photovoltaic electricity source and a shallow geothermal reservoir as a heat source and heat sink during the heating and cooling season. A total of four cases have been evaluated for the Zagreb City location. The results represent a balance of both thermal and electric energy flows within the microgrid, as well as thermal recuperation of the reservoir. The levelised cost of energy for all cases, based on a 20-year modelling horizon, varies between 41 and 63 EUR/MWh. On the other hand, all cases show a decrease in CO2 emissions by more than 75%, with the best case featuring a reduction of more than 85% compared to the base case, where electricity and gas for heating are supplied from the Distribution System Operator at retail prices. With the use of close integration of electricity, heating and cooling demand and supply of energy, cost-effective decarbonisation can be achieved for the household sector.

Study of nuclear reactor external vessel passive cooling using computational fluid dynamics

Nuclear energy has recently re-gained support as a reliable source of carbon-free electricity. However, the safety of nuclear plants is still questioned, particularly in the wake of the tragic events in Fukushima. In response to this, the adoption of passive safety systems, providing cooling to the plant even in the absence of any active power, has been accelerated. However, the confident assessment of their effectiveness is still constrained by the large spatial scales involved, which makes experimental validation difficult and expensive. Additionally, the many complexities intrinsic to the prediction of natural convection makes the mathematical modelling of such systems problematic. In this paper, the development of computational fluid dynamics (CFD) as a reliable method to ultimately prove, and eventually improve, the passive safety features of reactors is described. The focus of the paper is external reactor vessel cooling. In the case of a reactor core melting, the core is kept inside the reactor vessel, which is cooled from the outside by natural convection after flooding the region of the containment that houses the vessel. More specifically, a recent experiment that simulates, at a reduced scale, cooling of the horizontal calandria vessel of a pressurized heavy water reactor, submerged in a water pool, is modelled using CFD. For this situation, of major relevance is the correct prediction of boiling on the external surface of the reactor vessel, and thermal stratification in the water pool, which could prevent lower regions of the pool from performing any heat transfer duty. Results from standard Reynolds-averaged Navier-Stokes based turbulent flow simulations demonstrate that more advanced models are needed for accurate simulation, specifically in view of the excessive mixing predicted by such approaches. In contrast, the development of a more advanced tool based on large eddy simulation (LES) is started from the prediction of thermal stratification in the water pool, for which good accuracy is demonstrated through comparisons with available data. Although further improvements are needed, and discussed, it is demonstrated that LES can provide a reliable tool for the analysis and design of passive safety systems and strategies, and the assessment of passive cooling effectiveness and reactor safety. Although computational effort remains the main constraint in using LES, computation times are not prohibitive, particularly given the continual increase in available computing resources.

Increasing DER integration through discrete intraday settlements

Deployment of distributed energy resources (DERs) is accelerating across the United States. These assets have the potential to provide cost-effective grid services and bulk power while supporting a low-cost energy transition to carbon-free electricity. Full integration of these resources into the bulk power system remains a barrier to unlocking the potential value of these assets. The regional wholesale energy markets, originally designed to integrate centralized, dispatchable power plants, must be reformed to adapt to the changing potential resource mix. The current day-ahead and real-time system is poorly designed for DERs. Day-ahead DER forecast errors create exposure to real-time price variations, as resources committed in the day-ahead market are required to rebalance in real-time, challenging the business model for DERs. New intraday markets with multiple discrete intermediate auctions between the day-ahead market and real-time market are needed to enable proper integration of DERs and efficient mitigation of forecast uncertainty risk. These markets must incorporate financially-binding commitments, closer-to-dispatch price signals, and adequate liquidity to ensure competition. Intermediate auctions should be built on top of existing intraday processes in each regional market, incorporating the principles of the existing market structures and leveraging the benefits of the centralized dispatch systems. Regional transmission organization (RTOs) and Independent System Operators (ISOs) should pursue and implement intermediate auctions to support fair, open, and efficient markets in the U.S.

Decarbonising gate operations through clean energy solutions

Civil aviation authorities, working with their airport, airline and aviation business partners, are developing plans to achieve carbon-neutral aviation growth from 2020. This paper discusses how, in order to meet this goal, the International Civil Aviation Organization (ICAO) Member States have agreed to a basket of measures for reducing carbon dioxide emissions from international aviation. One effective measure identified is replacing aircraft auxiliary power unit emissions with gate electrification systems and solar power as described in the United Nations Clean Development Mechanism small-scale methodology: solar power for domestic aircraft at-gate operations. ICAO, with funding support from international partners, has recently completed three airport pilot projects — in Cameroon, Jamaica and Kenya — that demonstrate how States can implement the solar at-gate measure. Beyond the direct application to auxiliary power units and gate electrification, the solar at-gate concept offers a more general approach as to how other airport electrification conversion projects, including ground support equipment, airport ground transportation and passenger vehicle use, can maximise emission reduction benefits by eliminating fossil-fuel combustion and replacing it with carbon-free electricity. This paper discusses the solar at-gate example, which demonstrates the opportunities associated with maximising airport electrification and supplying the new electricity demand with clean energy for carbon emission reductions consistent with the global efforts to address climate change, and at the same time, accelerating the achievement of the Sustainable Development Goals (SDGs) through innovation for a greener future.

Inefficient cooking systems a challenge for sustainable development: a case of rural areas of Sub-Saharan Africa

The use of low efficient cookstoves has several severe negative impacts. Burning solid fuels kills about 4 million people every year, a number which is higher than the combined impact of HIV-AIDS, malaria and tuberculosis. Moreover, most of the people affected are located in rural areas of Sub-Saharan Africa and other developing countries, where over 80% of the population still relies on biomass as their primary source of energy, being the electricity access only 43%. Low-efficiency cooking systems are also a major source of greenhouse gas emissions since solid fuel cooking in Sub-Saharan Africa accounts for 1.2 and 6% of global CO2 and black carbon emissions, respectively. Furthermore, widespread biomass collection by an increasing population in Sub-Saharan Africa is unsustainable, contributing to deforestation. Therefore, the impact of using traditional cooking systems is a challenge for the achievement of sustainable development targets in Sub-Saharan Africa and as a whole globally. There are several cooking technologies used in those rural locations, but there are no clear frameworks or polices to support sustainable cooking options, as well as a guide for users. This paper assesses several cooking technologies with its associated fuels and evaluated each technology in terms of energy consumption, CO2 emissions, health impacts and costs. It was concluded that compared with traditional wood fuel cookstoves, electric cookstoves can reduce the energy consumption by 95.7%, CO2 emissions by 100% (assuming renewable carbon-free electricity) and the life cycle cost by 94%, also avoiding over 180 mg/m3 PM2.5 concentrations per/household per year. Also, this paper indicates that a strong and collective effort is necessary from key stakeholders to switch from traditional and unsustainable cooking technologies and fuels to cleaner and sustainable cooking systems.