中國(guó)儲(chǔ)能網(wǎng)訊：導(dǎo)語(yǔ)｜Introduction
隨著化石燃料的大規(guī)模使用、森林砍伐和土地利用方式的變更，人類活動(dòng)導(dǎo)致大氣中的溫室氣體濃度不斷增加，引起全球氣候變暖。為應(yīng)對(duì)日益嚴(yán)峻的氣候挑戰(zhàn)，力爭(zhēng)在本世紀(jì)中期實(shí)現(xiàn)碳中和是全球共同的使命。實(shí)現(xiàn)碳中和的路徑是什么？實(shí)現(xiàn)碳中和的技術(shù)突破方向是什么？如何監(jiān)測(cè)和計(jì)量碳排放？本文匯聚來(lái)自8個(gè)國(guó)家、52個(gè)單位的58位學(xué)者（8位院士），系統(tǒng)評(píng)述了碳中和技術(shù)及前景，為全球?qū)崿F(xiàn)碳中和提供支撐。
With the extensive use of fossil fuels, deforestation, and land-use change, anthropogenic activities have contributed to the ever-increasing concentrations of greenhouse gases (GHGs) in the atmosphere, causing global climate change. In response to the worsening global climate change, achieving carbon (C) neutrality by the middle century is the most pressing task on the planet. What are the paths to C neutralization? What are the directions for technological breakthroughs to achieve C neutralization? How to monitor and measure C emissions? This review, prepared by 58 scientists from 8 countries and 52 research units, intends to provide insights into the innovative technologies that offer solutions achieving C neutrality and sustainable development.
圖1 圖文摘要
Fig. 1 Graphical Abstract
1. 可再生能源技術(shù)
Technologies for renewable energy
對(duì)標(biāo)碳中和，實(shí)現(xiàn)一次能源有序減量替代，需大力發(fā)展可再生能源?？稍偕茉词且粋€(gè)完整的技術(shù)體系，不僅需要太陽(yáng)能、風(fēng)能、地?zé)崮?、海洋能等，更需要?chǔ)能技術(shù)的配合，形成真正的新能源體系。核能與氫能具有清潔低碳、綠色環(huán)保等優(yōu)點(diǎn)，是實(shí)現(xiàn)碳中和目標(biāo)的重要技術(shù)；生物質(zhì)能也是實(shí)現(xiàn)能源結(jié)構(gòu)調(diào)整的重要支撐。本文總結(jié)了可再生能源大規(guī)模應(yīng)用中的關(guān)鍵核心技術(shù)，以及這些關(guān)鍵核心技術(shù)對(duì)實(shí)現(xiàn)碳中和目標(biāo)的影響，同時(shí)對(duì)這些技術(shù)未來(lái)的發(fā)展進(jìn)行了展望（圖2）。
Achieving C neutrality requires replacing fossil fuels with renewable energy sources. Harnessing the power of solar, wind, geothermal, ocean, nuclear, and H2 energy may help secure global energy security without relying on fossil fuels. Bioenergy is also important in reshaping the energy supply and consumption systems. Technologies for these renewable energy sources and their future development are discussed (Fig. 2).
圖2 可再生能源技術(shù)
Fig. 2 Technologies for renewable energy
2. 增強(qiáng)全球生態(tài)系統(tǒng)碳匯技術(shù)
Technologies for enhancing C sink in global ecosystems
為實(shí)現(xiàn)全球生態(tài)系統(tǒng)碳中和，迫切需要減少農(nóng)業(yè)食物源溫室氣體排放和提高生物圈的碳固持量（圖3）。選育優(yōu)良作物和家畜品種，農(nóng)田精準(zhǔn)灌溉、施肥與土壤增碳，優(yōu)化家畜飼養(yǎng)和糞便管理，變革基于土地利用的動(dòng)植食物生產(chǎn)等措施，以減少農(nóng)業(yè)食物源溫室氣體排放；實(shí)施可持續(xù)管理森林草地生態(tài)系統(tǒng)，增強(qiáng)巖石風(fēng)化作用和采用生物炭技術(shù)等措施提高陸地生態(tài)碳匯；通過保護(hù)濱海濕地與海洋生態(tài)系統(tǒng)，實(shí)施可持續(xù)海水養(yǎng)殖、人工涌升流和陸海一體化戰(zhàn)略，提升海洋生態(tài)系統(tǒng)碳匯能力。
Global agricultural food systems are the major source of global anthropogenic GHG emissions, while terrestrial and marine ecosystems are the most important global C sinks (Fig. 3). To avoid disastrous climate change, global ecosystems need to be reformed to increase C sequestration, biomass production, and food supply while lowering GHG emissions.
圖3 全球生態(tài)系統(tǒng)溫室氣體流通量、減排和吸收策略
Fig. 3 Overview of global GHG budget and strategies to promote GHG reduction and sequestration in global ecosystems
3. 解決全球廢棄物碳足跡問題
Tackling the C footprint of global waste
作為減少全球廢棄物碳足跡的有效策略，將固體廢棄物轉(zhuǎn)化為生物炭，能夠減少溫室氣體排放，實(shí)現(xiàn)碳封存，有利于促進(jìn)循環(huán)經(jīng)濟(jì)發(fā)展。大量有機(jī)廢棄物，如植物殘?bào)w、牲畜糞便、廚余垃圾、工業(yè)生物垃圾、動(dòng)物尸體等，都可制備生物炭。生物質(zhì)炭可用于土壤改良、環(huán)境修復(fù)、化學(xué)品生產(chǎn)、建筑材料和飼料配方（圖4）。
As an effective strategy to reduce the C footprint of global waste, thermochemical conversion of solid waste into biochar can bring multifunctional benefits to the circular economy in addition to climate change mitigation and C sequestration. A plethora of organic resources, such as crop residues, forest residues, livestock manure, food wastes, industrial biowastes, municipal biowastes, animal carcasses, are feedstocks that can be used to produce biochar for different purposes. Biochar is used in a variety of applications, including soil amendment, delivery of agrochemicals and microbes, environmental remediation, catalyst production, building material manufacturing, and feed formulation (Fig. 4).
圖4 零廢棄生物炭作為可持續(xù)發(fā)展的碳中和工具
Fig. 4 Zero waste biochar as a C-neutral tool for sustainable development
4. 碳捕集、利用和儲(chǔ)存的技術(shù)
Technologies for C capture, utilization, and storage
CCUS是捕集、利用和儲(chǔ)存CO2的技術(shù)，對(duì)實(shí)現(xiàn)碳中和至關(guān)重要。CCUS需要技術(shù)創(chuàng)新以實(shí)現(xiàn)低成本和近零能耗捕集，同時(shí)實(shí)現(xiàn)碳封存與地下資源開采協(xié)同和風(fēng)險(xiǎn)管理技術(shù)。未來(lái)的突破方向：化學(xué)鏈燃燒、多聯(lián)產(chǎn)、化石能源和可再生能源互補(bǔ)捕集CO2等技術(shù)。CO2轉(zhuǎn)化為燃料或者化工品也是碳減排的重要途徑（圖5）。
CCUS, technologies for carbon capture, utilization, and storage, are critical to achieving C neutrality (Fig. 5). CCUS technologies need innovations, targeting CO2 recovery with low energy or even zero energy penalty, and aiming collaborative optimization of CO2 storage and resource recovery and risk management. Chemicals-power polygeneration and chemical looping combustion with CO2 capture have the potentials to realize low-cost CO2 capture. Fossil fuels combined with renewable energy for CO2 capture, the complementary energy systems, may play an important role for future CCUS. The conversion of CO2 into fuels and chemicals is a promising direction for C reduction.
圖5 工業(yè)體系二氧化碳捕集技術(shù)發(fā)展的路線圖
Fig. 5 The roadmap for CO2 capture technology development in the industry
5. 衛(wèi)星對(duì)地觀測(cè)與數(shù)字地球技術(shù)
C neutrality based on satellite observations and digital earth
衛(wèi)星對(duì)地觀測(cè)和數(shù)字地球技術(shù)是空天地一體監(jiān)測(cè)碳循環(huán)的重要手段，能為碳中和研究提供高時(shí)空分辨率的基礎(chǔ)觀測(cè)數(shù)據(jù)和分析工具。碳衛(wèi)星、多光譜衛(wèi)星為監(jiān)測(cè)溫室氣體濃度提供數(shù)據(jù)支撐；數(shù)字地球技術(shù)綜合全球植被、大氣、氣候數(shù)據(jù)，為自然生態(tài)系統(tǒng)碳收支提供時(shí)空分析與可視化展示。
Satellite observation and digital earth technology are important parts of monitoring C emissions and establishing an air-space-ground integrated observation system for the C cycle. They can provide basic observation and analysis data with a high temporal and spatial resolution for C neutralization research. C satellite and multispectral satellites can provide data support for monitoring the concentration of greenhouse gases; digital earth technology can integrate global vegetation, atmosphere, and climate data to provide temporal and spatial analysis of the C budget of natural ecosystems.
總結(jié)與展望 | Conclusions & perspectives
世界正朝著碳中和邁進(jìn)，未來(lái)需構(gòu)建以清潔能源為主體的新型電力系統(tǒng)，實(shí)現(xiàn)一次能源有序減量替代和可再生能源的大規(guī)模應(yīng)用；統(tǒng)籌生態(tài)系統(tǒng)保護(hù)和固碳功能，推進(jìn)基于土地利用與食物生產(chǎn)變革，提高陸海一體生態(tài)碳匯；優(yōu)化生物炭生產(chǎn)和生命周期過程，制定標(biāo)準(zhǔn)推進(jìn)低碳產(chǎn)業(yè)發(fā)展；利用多聯(lián)產(chǎn)技術(shù)、化學(xué)鏈燃燒技術(shù)、化石燃料與可再生能源互補(bǔ)技術(shù)，解決CCUS技術(shù)推廣高能耗高成本障礙；發(fā)展新型衛(wèi)星，全面監(jiān)測(cè)溫室氣體排放和陸海碳匯，星地協(xié)同增強(qiáng)碳收支核算能力。全球須通力合作、技術(shù)共享，以早日實(shí)現(xiàn)碳中和與可持續(xù)發(fā)展。
As the world races towards C neutrality, it is critical to revise current global C fluxes. To meet the climate change mitigation goals by the middle century, all people including investors, researchers, policy makers and consumers must work together:
(1) To realize orderly reduction and replacement of fossil fuel energy sources with renewable energy sources, we need to vigorously develop energy storage systems to address the intermittency of renewable energy sources. (2) To coordinate ecosystem protection and carbon sequestration, we need to push forward reform of crop-livestock production systems based on land use and improving ecological carbon sink. (3) To integrate ecological strategies optimizing biochar production, life cycle analysis, and formulate standards to advance the development of green and low-carbon industries. (4) To adopt breakthrough CCUS technologies including polygeneration, chemical looping combustion, and fossil fuels combined with renewable energy for CO2 capture, to overcome the high energy consumption and high costs. (5) To develop new satellites to comprehensively and timely monitor GHG emissions, and to expand the ability to calculate C budgets through joint observation from space and the ground.
