By Sonia Aggarwal, Mike O’Boyle, and Amol Phadke

通过 索尼娅AGGARWAL ， 迈克·奥博伊尔 和 阿莫尔Phadke

150 million Americans regularly breathe unhealthy, polluted air. But recently announced targets to achieve 100 percent clean power by the House Select Committee on the Climate Crisis and Joe Biden’s presidential campaign would eliminate all air pollution from power plants.

1.5亿美国人定期呼吸不健康，被污染的空气 。 但是最近由众议院气候危机特别委员会宣布的实现100％清洁能源的目标以及乔·拜登的总统竞选活动将消除发电厂的所有空气污染。

The public health benefits of realizing 100 percent zero carbon electricity by 2035 would be enormous. New analysis from Energy Innovation’s Energy Policy Simulator shows that reaching 100 percent by 2035 would avoid around 16,000 premature deaths in that year, as well as 425,000 asthma attacks, 19,000 heart attacks, and more, as shown in the table below. Moreover, avoiding all these negative health impacts creates massive economic productivity gains — getting to 100 percent in 2035 would avoid losing about 1.7 million workdays to poor health.

到2035年实现100％零碳电力的公共健康利益将是巨大的。 Energy Innovation的Energy Policy Simulator的新分析表明， 到2035年，这100％的比例将避免当年避免约16,000例过早死亡，并避免425,000例哮喘发作，19,000例心脏病发作，如下表所示。 此外，避免所有这些不利的健康影响会带来巨大的经济生产力提高，到2035年达到100％可以避免因健康状况不佳而损失大约170万个工作日。

Beyond improving health, getting to 100 percent zero carbon electricity would also be a boon for the climate, eliminating more than a quarter of America’s greenhouse gas (GHG) emissions in 2035. Zero carbon electricity can also enable further emissions reductions from transport, buildings, and industry via electric vehicles, efficient electric appliances, and electric industrial processes. Moreover, successfully decarbonizing our electricity sector would provide spillover benefits beyond our borders — in the form of technology available at lower costs to help reduce GHG emissions in other countries, as well as a clear signal to the world that U.S. is serious about addressing climate change.

除了改善健康状况外，达到100％的零碳电力也将为气候带来福音，到2035年消除超过美国四分之一的温室气体(GHG)排放。零碳电力还可以进一步减少交通，建筑，以及通过电动汽车，高效电器和电气工业流程进行的工业。 此外，成功地使我们的电力部门脱碳将以较低的成本提供技术形式，以帮助减少其他国家的温室气体排放，并向世界发出明确的信号，美国正认真对待应对气候变化，这将为我们提供超越国界的溢出效益。 。

All these social benefits — health and climate — really add up. The avoided climate damages between 2020 and 2035 total about $500 billion, using the social cost of carbon developed under the Obama administration. Economists would value the avoided health impacts over the same period around $690 billion, so the combined health and climate benefits of achieving 100 percent zero carbon electricity reach about $1.2 trillion by 2035 (assuming a 3 percent discount rate).

所有这些社会福利-健康和气候-确实加起来。 2020年至2035年期间，避免的气候损失总计约5,000亿美元，其中使用了奥巴马政府领导下的碳排放社会成本。 经济学家们估计，同期避免的健康影响约为6900亿美元，因此，到2035年，实现100％零碳电力所带来的健康和气候效益的总和将达到约1.2万亿美元(假设贴现率为3％)。

If these public health and climate benefits were not reason enough to decarbonize the electricity system, getting onto this path drives investment, supporting at least 500,000 healthy and safe new jobs just when our economy could really use them in the current situation of massive unemployment.

如果这些公共健康和气候效益不足以使电力系统脱碳，那么走上这条路就可以推动投资，至少在当前失业率高企的情况下，我们的经济才能真正利用这些就业机会，至少支持500,000个健康安全的新工作。

Given these overwhelming benefits, the critical outstanding question is whether all this will be affordable for American electricity consumers, and the answer is thankfully “yes!”

鉴于这些压倒性的好处，一个关键的悬而未决的问题是，这一切对于美国的电力消费者而言是否可以负担得起，答案是“可以！”

The 2035 Report, a recent study by researchers from the University of California-Berkeley, confirms the U.S. could get 90 percent of its electricity from zero carbon sources by 2035. Detailed grid modeling underlying the study shows electricity demand being met reliably in every hour between now and 2035 under a variety of weather scenarios. What’s more, ever-cheaper wind, solar, and batteries enable us to reach 90 clean electricity while reducing wholesale electricity costs 10 percent from today’s levels.

加州大学伯克利分校的研究人员最近进行的一项研究《 2035年报告》证实，到2035年 ，美国可以从零碳源中获取90％的电力。该研究所依据的详细网格模型显示，在此期间的每一小时中，可靠地满足了电力需求现在和2035年在各种天气情况下。 而且，更便宜的风能，太阳能和电池使我们能够达到90股清洁电力，同时将批发电力成本从如今的水平降低了10％。

Compared with other studies of its kind, the 2035 Report focused on how affordable it would be to get most of the way there on decarbonizing the electricity sector, much faster than conventional wisdom has typically suggested. And most of the public health and economic benefits come from reaching 90 percent, so it’s a no-regrets path to start down now.

与同类研究相比，《 2035年报告》侧重于以大多数方式实现电力行业脱碳的负担能力，这比传统观点通常所建议的要快得多。 而且大多数公共健康和经济收益来自达到90％的水平，因此从现在开始这是不容小reg的道路。

But of course, when we talk about 90 percent clean by 2035, the next questions become: What about that last 10 percent, especially considering recently announced policy goals calling for 100 percent? How would we build on 90 percent to get to 100 percent clean? What would the system look like, and how quickly could we realistically achieve 100 percent? Could we even do it by 2035 without breaking the bank, or the electric grid for that matter?

但是，当然，当我们谈论到2035年达到90％的清洁度时，接下来的问题就变成了：那最后的10％呢？尤其是考虑到最近宣布的政策目标要求100％清洁？ 我们将如何在90％的基础上获得100％的清洁度？ 该系统将是什么样子，而实际上要多快才能达到100％？ 我们能在2035年之前做到这一点而又不破坏资金或电网吗？

Many academics, researchers, and consultants have explored questions about how to decarbonize the last 10 percent of the electricity system. Unlike the first 90 percent, which can be achieved with well-known and commercially proven technologies, the last 10 percent raises serious questions about how to best match clean electricity supply with demand, especially during multi-week periods of low wind and sun, or when seasonal demand (for heat or air conditioning, for example) does not match regional clean energy availability. And if the imperative is reducing overall pollution and climate impacts, there are cheaper and easier sources for the same reductions — from our vehicles or buildings, for example.

许多学者，研究人员和顾问都探讨了有关如何使电力系统的最后10％脱碳的问题。 与前90％可以通过众所周知且经过商业验证的技术来实现的方法不同，后10％提出了有关如何使清洁电力供应与需求最佳匹配的严峻问题，尤其是在几周的低风和日照期间，或者当季节性需求(例如供热或空调)与区域清洁能源供应不匹配时。 而且如果必须要减少总体污染和气候影响，那么有同样便宜的更便宜，更容易获得的资源，例如我们的车辆或建筑物。

But to explore whether 100 percent zero carbon electricity is possible by 2035, let’s start with a couple stats about the first 90 percent. First, the 2035 Report shows that developers would need to install solar and wind at double the historical-best rate throughout the 2020s, and triple the historical-best rate in the 2030s. This increased pace will be challenging, but certainly reasonable. So reasonable, in fact, that there is likely some room to go even faster if the policy environment is right.

但是，要探讨到2035年是否有可能实现100％的零碳电力，让我们从前90％的一些统计数据开始。 首先，《 2035年报告》显示，开发商将需要在整个2020年代将太阳能和风能的安装价格提高到历史最高水平的两倍，并在2030年代将其安装到历史最高水平。 增长的步伐将具有挑战性，但肯定是合理的。 实际上，如此合理，以至于如果政策环境合适的话，还有可能还有更快的发展空间 。

Second, the 2035 Report findings indicate it is possible to decrease wholesale electricity rates by approximately 10 percent from today’s levels even as the system reaches 90 percent zero carbon. This creates a reasonable budget to get rid of the last ~200 million metric tons of carbon dioxide (CO2) emissions while keeping wholesale costs similar to today’s levels.

其次，《 2035年报告》的调查结果表明，即使系统达到零碳排放量的90％，也有可能将批发电价从目前的水平降低大约10％。 这将产生合理的预算，以消除最后的约2亿吨二氧化碳(CO2)排放，同时保持批发成本与当今水平相当。

An illustrative analysis by the University of California-Berkeley and Energy Innovation team indicates America may be able to reach a zero-carbon electricity system without meaningfully raising wholesale electricity rates from today’s levels with a combination of technologies not yet commercialized but currently on the horizon:

加利福尼亚大学伯克利分校和能源创新团队进行的一项说明性分析表明，美国可能可以实现零碳电力系统，而无需通过将尚未商业化但目前正在酝酿的技术相结合来将批发电价从当今水平显着提高：

• Using hydrogen produced by green electricity in gas turbines retrofitted to burn pure hydrogen在改造后的燃气轮机中使用绿色电力产生的氢气燃烧纯氢气
• Using hydrogen produced by green electricity in in fuel cells在燃料电池中使用绿色电力产生的氢气
• Burning synthetic methane or biogas in existing gas plants在现有的煤气厂中燃烧合成甲烷或沼气
• Capturing and sequestering CO2 from existing gas plants从现有的煤气厂中捕获和封存二氧化碳
• Direct air capture of CO2 from ambient air直接从周围空气中捕获二氧化碳

Green hydrogen is already capturing the attention of large utilities that are serious about decarbonization such as Los Angeles Department of Water and Power (LADWP) and NextEra Energy. LADWP’s latest planned 840 megawatt (MW) natural gas plant will run on 30 percent hydrogen on day one of its operation beginning in 2025, with plans to run it on 100 percent hydrogen by 2045. NextEra has proposed a $65 million pilot in Florida that will use a 20 MW electrolyzer to produce 100 percent green hydrogen from solar power, and blend it into another existing gas plant.

绿氢已经引起了重视脱碳的大型公用事业公司的关注，例如洛杉矶水电局(LADWP)和NextEra Energy。 LADWP最新计划的840兆瓦(MW)天然气电厂将从 2025年开始运营的第一天就以30％的氢气运行，并计划到2045年以100％的氢气运行。NextEra 建议在佛罗里达州进行6500万美元的试点 ，使用20兆瓦的电解槽从太阳能中产生100％的绿色氢气，然后将其混合到另一个现有的天然气工厂中。

Meanwhile, Europe’s latest hydrogen strategy is calling for 6 gigawatts (GW) of electrolyzers by 2024, scaling to 40 GW by 2030. Given that the continent has less than 1 GW of electrolyzers today, this will require a massive scale-up in a relatively short timeframe. This is worth watching, and if successful, has a real chance of helping to bring down costs of electrolysis in the U.S.

同时，欧洲最新的氢气战略要求到2024年将达到6吉瓦(GW)的电解槽 ，到2030年将达到40 GW。鉴于该大陆目前的电解槽不足1 GW，这将需要在相对规模的基础上进行大规模扩大时间短。 这值得一看，如果成功的话，它确实有机会帮助降低美国的电解成本

Using conservative cost estimates for hydrogen retrofits and green hydrogen costs from electrolyzers (a relatively mature — but still relatively expensive — technology), we find that retrofitting all the remaining gas plants in the 2035 Report to burn 100 percent green hydrogen would cost somewhere between 11.7–14.8 cents per kilowatt-hour (cents/kWh). Combined with the costs of the first 90 percent zero carbon electricity, this pathway would result in overall wholesale electricity rates around 5.3–5.6 cents/kWh in 2035, which is quite similar to today’s average rate of 5.2 cents/kWh.

使用保守的氢气改造成本估算和电解器产生的绿色氢气成本(一种相对成熟但仍然相对昂贵的技术)，我们发现，将2035年报告中所有剩余的天然气工厂改造为燃烧100％的绿色氢气将花费大约11.7欧元每千瓦时–14.8美分(美分/ kWh)。 结合最初90％的零碳电力的成本，这种途径将导致2035年的整体批发电价约为5.3-5.6美分/千瓦时，与今天的平均电价5.2美分/千瓦时非常相似。

Another pathway for green hydrogen in the electric power sector would be as storage via fuel cells. Producing the last 10 percent of zero carbon electricity beyond the 90 percent zero carbon system modeled in the 2035 Report would result in electricity rates in the range of 8.5–14.3 cents/kWh, resulting in overall wholesale electricity rates ranging from 5–5.6 cents/kWh in 2035, which is right in the range of today’s average rate.

电力部门中绿色氢的另一条途径是通过燃料电池进行存储。 超出2035年报告中模型的90％零碳系统生产最后的10％零碳电价，将导致电价介于8.5–14.3美分/千瓦时之间，导致整体批发电价介于5–5.6美分/ 2035年的千瓦时，正好在今天的平均费率范围内。

Green synthetic methane relies on chemical processes to convert green hydrogen into methane to be burned in existing gas power plants. This zero-carbon fuel source has the advantage of being directly usable in existing power plants, however it requires additional energy to convert electrolyzed hydrogen into methane, increasing input fuel costs relative to hydrogen. Blending synthetic methane with biomethane, captured from landfills or dairy farms, could reduce these input costs, though biomethane sources are relatively limited. At the same time, transporting green synthetic methane (a potent greenhouse gas in itself) using existing natural gas pipeline infrastructure could still result in significant leakage, offsetting the emissions benefits.

绿色合成甲烷依靠化学过程将绿色氢转化为甲烷，然后在现有的燃气发电厂中燃烧。 这种零碳燃料源具有可直接在现有发电厂中使用的优势，但是它需要额外的能量才能将电解氢转化为甲烷，从而增加了相对于氢的输入燃料成本。 尽管生物甲烷源相对有限，但将合成甲烷与从垃圾填埋场或奶牛场捕获的生物甲烷混合可以降低这些投入成本。 同时，使用现有的天然气管道基础设施运输绿色合成甲烷(本身就是有效的温室气体)仍可能导致大量泄漏，从而抵消了排放的好处。

Using conservative cost estimates for green methane, we find burning 100 percent green methane in the remaining gas fleet from the 2035 Report would cost about 12.6–14.7 cents/kWh, resulting in overall wholesale electricity rates around 5.4–5.6 cents/kWh in 2035, which is as again similar to today’s average rate.

根据保守的绿色甲烷成本估算，我们发现，《 2035年报告 》中剩余燃气中100％燃烧绿色甲烷的成本约为12.6-14.7美分/千瓦时，导致2035年整体批发电价约为5.4-5.6美分/千瓦时，这再次类似于今天的平均汇率。

Carbon capture and sequestration has been piloted in the U.S. The Petra Nova power plant project in Texas retrofitted an existing coal-fired power plant to capture 90 percent of its emissions. The captured CO2 is compressed, dried, and transported to the West Ranch Oil Field in Jackson County, Texas, then pumped underground to boost oil production in a process called “enhanced oil recovery.” However, it is important to note Petra Nova was recently mothballed because low oil prices no longer justify purchasing the captured CO2 for enhanced oil recovery. The whole carbon capture, transport, and sequestration process is still relatively expensive, and only economically justified as a pilot when used for oil recovery at relatively high oil prices.

碳捕集与封存已在美国进行了试点。德克萨斯州的Petra Nova电厂项目改造了现有的燃煤电厂，以捕集其90％的排放。 捕获的二氧化碳经过压缩，干燥并输送到德克萨斯州杰克逊县的西牧场油田，然后通过称为“强化采油”的过程泵入地下以提高石油产量。 但是，重要的是要注意，Petra Nova最近被封存，因为低油价不再有理由购买捕获的二氧化碳以提高采油率。 整个碳捕获，运输和封存过程仍然相对昂贵，并且只有在以较高油价用于石油采收时才在经济上作为试点是合理的。

Using conservative cost estimates for retrofitting existing gas plants with carbon capture technology, and accounting for transportation and sequestration costs, we find capturing 90 percent of carbon emissions from the remaining gas fleet in the 2035 Report would cost about 11.4 cents/kWh, resulting in overall wholesale power costs around 5.3 cents/kWh in 2035, which is about the same as today’s average wholesale rate. Note this would leave about 20 million tonnes of electric power sector GHG emissions, which would need to be offset in other ways — perhaps via direct air capture, as described next.

使用保守的成本估算来利用碳捕获技术改造现有的天然气工厂，并考虑运输和封存成本，我们发现在2035年报告中捕获剩余天然气车队90％的碳排放将花费约11.4美分/ kWh，因此总体上2035年，批发电力成本约为5.3美分/千瓦时，与今天的平均批发价格相同。 请注意，这将留下约2000万吨的电力部门温室气体排放量，这需要以其他方式进行补偿-可能通过直接空气捕获来弥补，如下所述。

Direct air capture (DAC) of CO2 is a nascent technology with potential to scale and see cost reductions over time. A recent techno-economic assessment of DAC found that demonstration projects could capture CO2 at costs around $350/ton today. The same study (and projections by company Carbon Engineering) found costs could drop below $200/ton with significant commercialization. Using waste heat could further reduce costs.

二氧化碳的直接空气捕获(DAC)是一项新兴技术，具有随着时间推移而扩大规模并降低成本的潜力。 DAC的最新技术经济评估发现，示范项目现在可以以约350美元/吨的成本捕获CO2。 同一项研究(以及Carbon Engineering公司的预测 )发现，随着大量的商业化生产，成本可能降至200美元/吨以下。 使用废热可以进一步降低成本。

DAC is a particularly flexible option to offset the final electric sector emissions because it does not require co-location with any generator, and could also provide grid benefits by operating as a flexible source of electricity demand, running when “excess” zero carbon electricity is being generated. As such, DAC could complement any other pathway to 100 percent, and provides a de facto cost ceiling for reaching net zero emissions for the electricity system.

DAC是一种抵消最终电力部门排放的特别灵活的选择，因为它不需要与任何发电机并置，并且还可以通过作为灵活的电力需求源(在“零”零碳电力是正在生成。 因此，DAC可以将任何其他途径补充到100％，并为达到电力系统的净零排放量提供了事实上的成本上限。

Using best available cost estimates for capturing the approximately 200 million tonnes of CO2 emitted by the remaining gas fleet in the 2035 Report, and accounting for transportation and sequestration costs, we find using DAC for offsets would imply an equivalent “cost of generation” for the last 10 percent of between 11–19 cents/kWh.

根据2035年报告中使用的最佳成本估算来捕获剩余天然气车队排放的大约2亿吨CO2，并考虑运输和封存成本，我们发现使用DAC来抵消将意味着碳当量的“发电成本”相当。在11-19美分/千瓦时之间的最后10％。

Where exactly this option lands in this range depends on whether DAC is deployed at any meaningful scale in the 2020s, and whether that deployment results in cost reductions over time. These estimates would put total average wholesale power costs for 100 percent net zero electricity using DAC for the last 10 percent somewhere between 5.2–6 cents/kWh in 2035, which is as much as 15 percent higher than today’s average wholesale rate.

该选项在此范围内的确切位置取决于DAC是否在2020年代以任何有意义的规模部署，以及该部署是否会导致成本随时间降低。 这些估算值将得出2035年使用DAC的最后10％的总平均批发电力成本为100％净零电，介于5.2-6美分/千瓦时之间，比今天的平均批发价格高出15％。

In sum…

总共…

It’s true that eliminating the last 10 percent of electricity system emissions is more expensive than the first 90 percent, and the priority should remain on accelerating clean energy build-out now to get on either pathway. But summiting the 100 percent mountain is likely not as hard as pessimists would have us believe, especially since it is possible to deliver the first 90 percent zero carbon system, keeping the grid in balance in every hour, while reducing power costs 10 percent from today’s levels.

的确，消除电力系统的最后10％的排放比开始的90％的排放更昂贵，现在应该优先考虑加快清洁能源的建设，以走上任何一条道路。 但是登顶100％的山峰并不像悲观主义者所想象的那么难，特别是因为有可能提供第一个90％的零碳系统，使每小时的电网保持平衡，同时将电力成本从今天的水平降低10％。水平。

At least four promising technology pathways exist today to reach 100 percent clean electricity by 2035 without meaningfully raising wholesale costs from today’s levels, and a fifth might raise them 15 percent. Combining these pathways, along with further expected cost declines from solar, wind, and storage, as well as more potential contribution from demand-side flexibility, we are optimistic these cost estimates could be bested by America’s world-class innovators. Add in significant federal research and development funding, and further cost reductions and innovation are likely.

如今，至少存在四种有前途的技术途径，可以在2035年之前达到100％的清洁电力，而不会从目前的水平上显着提高批发成本，而第五种可能会将其提高15％。 结合这些途径，再加上太阳能，风能和储能的预期成本进一步下降，以及需求方灵活性带来的更多潜在贡献，我们乐观地认为，这些成本估算可以被美国的世界级创新者所超越。 增加大量的联邦研究与开发资金，可能会进一步降低成本和进行创新。

But a clear and specific policy target is essential to set us on the way. With no time to lose, now is the time for ambitious leadership. A zero-carbon electricity system is achievable and affordable, so what are we waiting for?

但是，明确而具体的政策目标对我们的前进至关重要。 没有时间可以浪费了，现在是进行雄心勃勃的领导的时候了。 零碳电力系统是可以实现且负担得起的，那么我们还等什么呢？

Sonia Aggarwal is vice president of Energy Innovation, where she leads the firm’s policy and analytical programs.

Sonia Aggarwal是能源创新部副总裁，负责公司的政策和分析计划。

Mike O’Boyle is director of electricity policy at Energy Innovation, where he leads the firm’s Power Sector Transformation program.

Mike O'Boyle是能源创新公司电力政策总监，他领导该公司的电力行业转型计划。

Amol Phadke is a senior scientist and affiliate at the Goldman School of Public Policy, University of California-Berkeley.

Amol Phadke是加利福尼亚大学伯克利分校高盛公共政策学院的高级科学家和分支机构。