煤炭制氢vs甲烷制氢vs电解水制氢：成本分析

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原创 Becky hydrogenfuelcellinfo

Coal vs methane vs water The future of hydrogen production

煤炭制氢 vs 甲烷制氢 vs 电解水制氢：成本分析

Hydrogen perspectives from Silicon Valley is a series by Karen Baert and Thilo Braun, MBA students at Stanford University, to shed light on trends and innovation in hydrogen. This is the second post in a series surveying the industry.

本文来自于斯坦福大学MBA学生Karen Baert 和 Thilo Braun系列文章。该文章旨在阐明氢能发展趋势和创新技术。本文是该系列文章的第二篇。

Humans have been producing hydrogen for hundreds of years. Today, more than 100 million metric tons of hydrogen are produced a year – enough to fill more than 500 million Olympic swimming pools at ambient pressure.

数百年以来人类一直都在进行制氢。如今每年生产的氢超过1亿吨-足以在压力环境下填充5亿多个奥林匹克游泳池。

More than 95% of the hydrogen produced today is produced from fossil fuels, emitting almost 10kg of CO2 per kg of hydrogen produced. Why then is hydrogen considered a clean alternative to fossil fuels?

如今的氢95%以上是由化石燃料生产的，每生产1公斤氢都会排放接近10公斤CO2，那么问题来了，为什么氢气还是被认为是化石燃料的清洁替代品呢？

This article is focused on the supply side of hydrogen:

本文重点介绍氢气供应端：

The colours of the hydrogen rainbow

Green: The promise of electrolysers

Green hydrogen cost: Why wind and solar energy change the equation

Green hydrogen cost: Carbon taxes will help favor green but won’t do it on their own

1. 氢的颜色表述：氢气彩虹

2. 绿色：电解槽的承诺

3. 绿氢成本-为什么风能和太阳可以改变进程

4. 绿氢成本：碳税将有利于绿氢，但不会主动进行

The colours of the hydrogen rainbow

氢气彩虹

Hydrogen comes in many different colors. You may have come across references to blue, green, turquoise, grey and maybe even gold hydrogen amongst other colors. If this leaves you confused, you are not alone.

有许多不同颜色的氢。您可能遇到过蓝氢、绿氢、绿松石氢、灰氢，甚至可能是金氢及其它颜色的氢。如果您感到很迷糊，放心吧，您不是一个人。

The different colours are used to categorise different types of hydrogen production technologies. Hydrogen has been produced for centuries and is essential for our world today. Without it, most of us would not have any food on the table as hydrogen is an essential component in making fertiliser.

不同的颜色表示对不同技术类型生产的氢进行分类。氢气的生产已进行了几个世纪，但氢气对我们如今的世界变得至关重要。没有了它，我们大多数人的餐桌上就没了任何食物，氢是生产肥料的重要组成部分。

However, historically production has been from fossil fuels. The majority of hydrogen today is grey hydrogen, which is produced from natural gas through a process called steam methane reforming (SMR) or through coal gasification. Hydrogen produced through the gasification of coal is called brown or black hydrogen, using bituminous (black) or lignite (brown) coal.

一直以来都在用化石燃料生产氢气。如今大部分的氢是灰氢，它是通过蒸汽甲烷重整SMR的过程或是煤气化天然气来生产的。煤气化生产的氢被称为棕氢或是黑氢，因为该过程利用的是烟煤（黑色煤）或是褐煤（棕色煤）。

A number of technologies have emerged that enable producing hydrogen with no or little carbon emissions including blue, green and turquoise hydrogen.

现已出现许多技术可在没有排放或是有很少排放的情况下生产氢气。这就包括了蓝氢、绿氢和绿松石氢。

Blue hydrogen – a temporary stopgap

蓝氢——权宜之计

Blue means retrofitting existing plants with carbon capture and storage (CCS). This can be done on existing infrastructure with moderate investment costs. Starting at roughly $0.20 per kg hydrogen, CCS only adds a modest cost the output hydrogen.

蓝氢意味着利用碳捕捉和存储技术CCS技术改造现有工厂。这可通过在现有工厂的基础设施上进行适度投资完成。CCS技术增加了每公斤氢0.2美元的成本。

A major concern with blue hydrogen is what to do with the captured CO2, with many geographies not being amenable to carbon sequestration. Furthermore, while high rates of carbon capture (90-95%) are possible, high throughput incentivises reducing the rate of capture. Nonetheless, there are a number of major blue hydrogen projects including Australia’s project to produce blue hydrogen from coal gasification for export to Japan. As it only leads to a partial GHG emission reduction, we see blue hydrogen primarily as a temporary solution to reduce the carbon impact of existing SMR facilities.

蓝氢所面临的一个主要问题是如何处理捕捉的CO2。有许多地区不合适CO2的封存。此外，虽然CO2高捕捉率（90%-95%）是可能的，但高流通量会降低CO2的捕捉率。尽管如此，世界上仍有些主要的蓝氢项目，包括澳大利亚利用煤气化生产的蓝氢出口到日本的项目。因蓝氢只会带来部分温室气体排放减少，所以我们认为蓝氢只是一种临时解决方案，以减少现有的SMR设施的碳排放影响。

Turquoise – cheap gas

绿松石氢-廉价的天然气制氢

Turquoise is a relatively new process where methane pyrolysis is used to produce hydrogen. The input is methane (or natural gas) which is easy to come by. Rather than CO2, the process creates carbon black as a by-product. Unlike CO2, carbon black is a solid product and hence easy to capture and use or sequester. Carbon black in turn is used to produce the rubber for tires amongst other applications, giving it resale value rather than being a pure waste product.

绿松石氢是一种相对较新的制氢工艺，它利用甲烷热解生产氢气。甲烷或是天然气是容易获得的。该过程的副产物不是CO2而是炭黑。和CO2不同，炭黑是一种固体产品，因此更容易捕捉、利用或是存储。炭黑可用于生产轮胎橡胶及其它产品，具有转售价值，而不是纯粹的废品。

While the process itself does not emit any greenhouse gas emissions, there is a risk from upstream emissions. Methane leaks in the process can lead to significant lifecycle emissions. As long as this is managed (which we know how to do, verified by companies like Project Canary), turquoise hydrogen is a strong contender for producing clean hydrogen at economically attractive prices in the short term.

虽然该生产过程不会排放任何温室气体，但其上游存在排放风险。在生产过程中甲烷泄漏会带来明显的生命周期排放。只要这一点可得到管理（我们知道如何做到这点，已由Project Canary等公司验证）绿松石氢在短期内可以是以具有经济效益生产清洁氢的有力竞争技术。

Green hydrogen

绿氢

Green hydrogen is produced using water electrolysis and electricity. As long as the electricity is renewable, green hydrogen has no associated carbon emissions. The main challenge green hydrogen production faces today is cost – as these fall it will be increasingly broadly adopted. Nevertheless, the prospect of producing hydrogen with only water and green electricity as input and no greenhouse gas emissions is very promising. We believe green hydrogen will be the dominant production path in most regions worldwide and we will focus the remainder of this article on green hydrogen technologies and their economics.

绿氢是由电解水制氢而获得的。只要制氢的电力是可再生的，绿氢就没有碳排放。如今绿氢所面临的主要挑战是成本-随着成本的下降，绿氢就将会得到越来越广泛的采用。尽管如此，利用水和绿电生产没有温室气体排放的氢，前景广阔。我们相信绿氢将成为全球约大多数地区制氢的主要途径。本文的剩余部分将重点关注绿氢技术及其经济性。

The best of the rest

其它最佳制氢技术

Before diving into green hydrogen production, a number of other processes are worth mentioning.

在深入研究绿氢技术前，还有系列的其它制氢技术值得探讨。

Recently, there has been talk of natural reservoirs of hydrogen. The so called ‘gold hydrogen’ can be pumped out of the ground in a fashion similar to natural gas extraction today. To date, little is known about gold hydrogen, and more research is required before we will see it at scale.

最近有人开始谈论氢气的天然存储。所谓的金氢，类似于如今从地下抽出天然气的开采方式。迄今为止，人们对金氢知之甚少，在该技术进行大规模应用前还需要进行更多的研究。

Another form of hydrogen production is waste-to-hydrogen. Rather than burning biomass waste or putting it in a landfill, it can be used to produce comparatively cheap clean hydrogen. This is a relatively messy and complex process, but the economics do make it attractive as a part of the solution. We don’t expect waste-to-hydrogen to become dominant, but do see potential for it to take a noticeable share of clean hydrogen production in the next 15-10 years.

另一种制氢方式是废气物制氢。该技术可用来生产相对便宜的清洁氢，而不是将生物质废气物进行燃烧或是填入垃圾填埋场。该技术是一个相对混乱和复杂的过程，但作为解决方案的一部分，其经济性确实相当有吸引力。我们预计废气物制氢技术不会成为主流，但在未来5-10年内确实有潜力占据清洁氢的重要份额。

主要制氢技术对比表

Green: The promise of electrolysis

绿氢：水电解的承诺

Electrolysis is a decade old technology – dating as far back as 1800. However, to date, it has been too expensive to compete with grey hydrogen. Green hydrogen prices are two to four times as high as those of grey and the amount of grey hydrogen produced today is a rounding error. Then why do we care about green hydrogen?

水电解是一项具有百年历史的技术-它可追溯至1800年左右。不过迄今为止，和灰氢相比，绿氢的成本仍然太高了。绿氢的价格是灰氢的2-4倍左右，而如今生产的绿氢数量只是灰氢的零头（甚至可说以忽略不计）。我们为什么还要关心绿氢技术呢？

Green hydrogen is clean – it has no greenhouse gas emissions associated to its production. This doesn’t help much if it is far too expensive, but with the falling cost of renewable electricity, the cost of green hydrogen too is falling rapidly. Furthermore, green hydrogen can be produced anywhere there is a (renewable) electricity source and water, making it flexible geographically. Today, one of the largest cost components of hydrogen is its distribution. If an electrolyser enables producing closer to the site of use, significant cost savings can be had, in part offsetting today’s higher cost of production for distributed off-taker.

绿氢的生产是清洁的，没有温室气体排放。如价格太贵的话，随着可再生电力成本下降，绿氢的成本也在迅速下降。此外只要有电力和水，就可在任何地方生产绿氢，绿氢生产在地理位置上具有灵活性。如今，氢气最大的成本组成之一就是氢气的分销成本。如果电解槽可在用氢地点更近的地方制氢，则可明显节约成本，部分抵消如今分布式承购商较高的生产成本。

Cost curves for green hydrogen have been declining rapidly. Initiatives such as the US Department of Energy’s Hydrogen Shot are accelerating this cost decline, pursuing a target of 111 – $1 per 1 kg of hydrogen in 1 decade (by 2030). We anticipate that green hydrogen will be the preferred path for hydrogen manufacture beyond 2030 when costs approach those of grey hydrogen. A major remaining concern is water sustainability issues given the significant water input requirement for electrolysis.

绿氢的成本曲线下降很迅速。美国能源部的Hydrogen Shot等相关举措正加速绿氢成本下降，并争取在10年内（到2030年）实现每公斤氢气成本为1美元的目标。预计到2030年后，当绿氢成本接近灰氢时，绿氢技术将成为制氢的首选。考虑到当前水电解制氢需要大量的水，另一个主要问题是水的可持续供应。

We identified four main types of electrolysers. Without going into the technical details, it is worth being aware of their comparative advantages and disadvantages. Today, alkaline remain the most commonplace but most new projects are PEM. PEM electrolysers have the unique advantage of being able to ramp up and down quickly, making it possible to turn on when there is excess renewable power (the sun is shining or the wind is blowing more than there is demand) and to turn off when there is not.

我们今儿讨论四种类型的电解槽。在不深入技术细节的情况下，值得了解它们的比较优势和劣势。当下最常见的仍是碱性电解槽，多数新项目是PEM电解槽。PEM电解优势独特，可进行迅速的开关，从而可在可再生能源过剩时开启电解槽，而在电力不足时进行关闭。

Green hydrogen cost: Why wind and solar energy change the equation

绿氢成本-为什么风能和太阳可以改变进程

The extent and speed at which green hydrogen will contribute to decarbonising industry will be driven by the evolution of its production cost. The production cost (also known as levelised cost of green hydrogen production, or LCOH) is dependent on two main factors. One of them is the capital cost of electrolysers discussed above. The second and typically even more important factor is the availability of cheap renewable electricity, which can be broken down into two components: The electricity price and the capacity factor.

绿氢对工业脱碳的速度和程度取决于其生产成本的演变。绿氢产生成本取决于2个主要因素：其中之一是电解槽资本成本。第二个更重要的因素是廉价的可再生电力的可用性，它可分为2个-电价及容量因素。

The capacity factor represents the percentage of the maximum production capacity of an electrolyser utilized in a given period. The main reason for the capacity factor to be substantially below 100% is the availability and cost of electricity. When connecting an electrolyser to the grid, the capacity factor can be up to 100%, albeit may be lower to avoid buying electricity when it is most expensive. When directly connecting an electrolyser to a renewable power source, the capacity factor can range from ~25% for solar to ~35% for wind to ~100% when using non-intermittent sources of electricity.

容量系统表示，在给定时间内利用电解槽的最大生产能力百分比。容易系数远低于100%的主要原因是电力的可用性和成本。将电解槽连接至电网时，容量系数可高达100%，也可能会低些，以避免购买价格最高时候的电力。当将电解槽直接连接至可再生能源时，容量系数的范围可从太阳能的约25%至风能的35%到使用非间歇性电力时的约100%。

To better understand the (different components of) LCOH, we analysed the cost based on three different scenarios (numbers are based on BloombergNEF’s most optimistic estimates):

为更好的理解LOCH（不同的组成部分），我们据3种不同的情景分析了成本（数字基于彭博社新能源最乐观估计）：

Solar in United Arab Emirates: ~3ct/kWh at 20% capacity factor

Onshore wind in Brazil: ~2ct/kWh and 40% capacity factor

Hydropower in Iceland: ~4 ct/kWh at 90% capacity factor

阿联酋太阳能：容量系数为 20% 时约为 3ct/kWh

巴西陆上风电：~2ct/kWh 和 40% 的容量系数

冰岛水电：容量系数为 90% 时约为 4 ct/kWh

The below image represents the hydrogen cost and its breakdown in different cost buckets for each of these scenario’s. As visible in the graph, the opex/capex split is highly dependent on the capacity factor. While capex represents ~60% of the cost in the UAE case with 20% capacity factor, only ~25% of LCOH is related to capex in the Iceland case with 90% capacity factor.

下图显示了每种情况下的氢气成本及其在不同成本中的细分。如图所示，运营支出/资本支出拆分高度依赖于容量因素。在容量系数为 20% 的阿联酋案例中，资本支出占成本的约 60%，但在容量系数为 90% 的冰岛案例中，只有约 25% 的 LCOH 与资本支出相关。

To better understand the impact of capacity factor and renewable electricity cost, we ran the numbers in the three different scenarios for a 100MW PEM electrolyser with a CAPEX cost of $1,000/kW (with 8% WACC, 35% BoP, 1.1 installation factor). The below sensitivity table represents the levelised cost of hydrogen production with electricity cost between $1-8 ct/kwh and a capacity factor between 10 and 100%. This cost only represents production and does not take into account any costs for transportation or storage.

为了更好地理解容量因素和可再生电力成本的影响，我们对 100 兆瓦的 PEM 电解槽三种不同情景进行了计算，其 CAPEX 成本为 1,000 美元/千瓦（WACC 为 8%，BoP 为 35%，安装系数为 1.1）。下面的敏感度表代表了氢气生产的平准化成本，电力成本在 1-8 ct/kwh 之间，容量系数在 10% 到 100% 之间。此成本仅代表生产成本，不考虑任何运输或储存成本。

Some key takeaways from the analysis are:

分析要点：

The LCOH is significantly more sensitive to the cost of electricity than the capacity factor (Which is driven by the relative importance of opex versus capex). As electrolysers become cheaper, colocating them with renewable energy assets (with capacity factors of 30-50%) will be an increasingly economically attractive way to produce cheap green hydrogen.

与容量因素相比，LCOH 对电力成本的敏感度明显更高（这是由运营支出与资本支出的相对重要性所驱动的）。随着电解槽变得越来越便宜，将它们与可再生能源资产（容量系数为 30-50%）放在一起是生产廉价绿氢的在经济上越来越有吸引力的方式。

The LCOH of $1.1-6.5/kg of green hydrogen is a wide range though partly overlaps with the $0.7-2.5/kg of grey hydrogen. Electricity prices as low as 3 ct/kWh are needed for green hydrogen to become cost competitive with grey hydrogen. Geographies with cheap renewables will be at the forefront of green hydrogen adoption.

1.1-6.5 美元/千克绿氢的 LCOH 范围很广，与 0.7-2.5 美元/千克灰色氢有部分重叠。绿氢需要低至 3 ct/kWh 的电价才能和灰氢有成本竞争力。拥有廉价可再生能源的地区将处于绿氢采用的最前沿。

It is important to note that these costs are purely the production cost in isolation. Additional costs from compression, liquefaction, storage and distribution are significant for hydrogen and may change the playing field for green. Cost savings from locating electrolysers closer to where hydrogen is used can reduce delivered costs by as much as 50%. We will explore this more in our next article.

需要注意的是，这些成本纯粹是独立的生产成本。压缩、液化、储存和分配的额外成本对氢气来说意义重大，可能会改变绿氢的竞争环境。将电解槽安装在靠近氢气使用地点的地方可以节省成本，可以将交付成本降低 50%。我们将在下一篇文章中对此进行更多探讨。

Cost: Carbon taxes will help favour green but won’t do it on their own

成本：碳税有助于绿色环保，但不会主动进行

Finally, the cost competitiveness of green hydrogen versus grey hydrogen will improve remarkably if significant carbon incentives become widespread. As grey hydrogen production comes with 9kg CO2 emitted per kg hydrogen produced, grey hydrogen will become more expensive when carbon taxes are factored in. The below graphs illustrate the impact of carbon taxes on grey hydrogen prices compared to the green hydrogen production cost in 2022 and 2030, which is independent of carbon prices assuming the usage of 100% renewable electricity. The assumed electrolyser capex is $1,000/kW and $400/kW in 2022 and 2030 respectively. While carbon taxes will help to improve economic viability of green hydrogen, we need progress in electrolyser costs, efficiency, lifetime as well as increased availability of cheap renewable electricity for green hydrogen to disrupt the industry.

最终，如果显著的碳激励措施变得普遍了，绿氢和灰氢的成本竞争力将显著提升。每生产1公斤灰氢将会排放9公斤CO2，如考虑到碳税，灰氢将会变得更昂贵。下明说了和2022年绿氢生产成本相比，碳税对灰氢价格的影响，及2030年，假设利用100%可再生氢电力的碳价格无关。2022年和2030年假定的电解槽的资本支出分别为1000美元/千瓦和400美元/千瓦。虽然碳税有助于提升绿氢经济可行性，但我们需要在电解槽成本、效率、寿命及增加廉价可再生电力的可用性方面取得进展，以彻底改变这个行业。

Summary

总结

In the long term, green hydrogen is the most promising carbon-free hydrogen production method. The jury is still out on how the transition will look and different technologies might win for different applications.

长远来看，绿氢是目前最有前景的无碳制氢方式。至于这种转变将如何进行，以及不同的技术可能会在不同的领域胜出，目前尚未有定论。

The availability of cheap renewables will drive adoption of green hydrogen. Electrolysers are expected to be operated flexibly to (1) work with direct connection to renewables without the need for electricity storage (avoiding high costs from using the public grid for electricity distribution), or (2) to take advantage of volatility of prices on electricity market when connected to the grid.

廉价的可再生电力的可用性将促进的绿氢的采用。电解槽有希望灵活运行以（1）直接连接可再生能源，无需蓄电（避免使用公共电网进行配电的高成本），或 (2) 利用接入电网后电力市场价格的波动。

Carbon prices will help favour green over grey but will not move the needle on their own. Electrolyser cost reductions and technology improvements and the continued the deployment of renewables are indispensable for the green hydrogen industry to contribute to a net-zero economy.

碳价将有利于绿氢而不是灰氢，但不会自行发生变改变。电解槽成本的降低和技术改进及可再生能源的部署对于绿氢为净零经济做出贡献是必不可少的。

Finally, in this article we have looked at production cost in isolation. The ability to deploy electrolysers in a distributed fashion, locating them geographically close to the area of demand may reduce distribution costs significantly, with a potential to reduce the cost of delivered hydrogen by as much as 50%. Watch out for our next article where we dive into hydrogen storage and distribution.

在本文最后，我们单独研究了制氢成本。以分布式的方式进行电解槽部署的能力，将电解槽安装在靠近氢气需求区域可显著降低氢气分销成本，有可能将氢气的运输成本降低50%。下篇文章我们将深入探讨氢气的存储和分配。