编者按：日前 ，国际电力行业着名刊物《Power》刊登题为“ ？榛⒌绯д谔岣呖夏嵫堑厝刃省钡奈恼 ，向全球先容我集团首创的地热井口电站手艺及其成绩 。这是继新华社、《人民日报》等中国央媒先容ag亚娱集团在肯尼亚取得的成绩之后 ，又一个国际级媒体的推介 。
《Power Magazine》在全球电力行业具有显著的影响力 。作为全球最古老的能源行业期刊之一 ，自1882年创刊以来 ，已成为电力行业内的主要信息泉源和行业标准 。其影响力既源于权威性和历史性 ，还由于其拥有普遍的受众群体 ，读者涵盖了全球电力行业专业人士 ，包括电力工程师、运营司理、手艺专家、决议者和企业高管 ，它通过提供深入的手艺剖析、案例研究和行业新闻 ，资助专业人士做出更好的决媾和明确行业动态 。《Power Magazine》在全球电力行业饰演主要的角色 ，既是信息撒播的主要渠道 ，也是行业趋势和手艺生长的风向标 ，该刊物宣介ag亚娱集团地热井口 ？榈缯臼忠毡昙亲盼壹庞涤凶灾髦恫ǖ慕沟闶忠栈竦靡的谥髁髅教宓娜贤 ，也料将极大地推动ag亚娱集团手艺在全球的应用 。
下面是本编辑部转发的新闻链接和转载文章的中英文比照文本 ，以飨读者 。
原文链接：https://www.powermag.com/a-modular-power-plant-is-steaming-up-kenyas-geothermal-efficiency/
A Modular Power Plant Is Steaming Up Kenya's Geothermal Efficiency
Sosian Menegai during the commissioning phase. Courtesy: Kaishan Group
Sosian Menengai Geothermal Power, Kenya’s newest geothermal power plant, is powered by modular technology that maximizes efficiency, reduces costs, and enhances scalability.
Kenya’s scenic Rift Valley region is a literal hotbed of geothermal potential. Part of the vast East African Rift Valley System (EARS), a 6,400-kilometer (km) tectonic divergence that is cleaving the African continent into two plates, Kenya’s Rift Valley forms a vertical corridor of intensive faulting and volcanic activity, hot springs, fumaroles, and sulfur-oozing fissures. But while the country began geothermal exploration for power development in the 1950s, most of its investments have been focused on the Olkaria region situated within Hell’s Gate National Park near the flamingo-flecked Lake Naivasha in Nakuru County. Five of six geothermal power stations in Olkaria are owned by KenGen (with a combined capacity of 799 MW), while Nevada-based Ormat Technologies owns a 150-MW plant. Olkaria plants in 2023 provided nearly 45% of Kenya’s total generation, a sizeable contribution to the East African powerhouse’s meager 3.3-GW installed capacity.
In 2008, the Geothermal Development Co. (GDC), a state-owned special-purpose vehicle tasked with accelerating the nation’s geothermal resource development, expanded its focus to the Menengai region just north of Olkaria, at the site of a massive shield volcano with one of the biggest calderas in the world. While GDC says the Menengai complex harbors a potential of 1,600 MW, its long-term goal is to develop 465 MW of geothermal steam equivalent.
In 2013, it took the first step to competitively award the first three initial 35-MW power projects at the complex to three independent power producers (IPPs): Orpower 22 (a former subsidiary of New York firm Symbion now owned by China’s Kaishan Group), South African-based Quantum Power East Africa (now majority owned by UK firm Globeleq), and Nairobi-headquartered Sosian Energy. In August 2023, the first of these projects—Menengai III, now formally known as the Sosian Menengai Geothermal Power—wrapped up a 16-month construction timeframe and began delivering first power to the grid.
Map showing location of geothermal area along the Kenyan Rift Valley. Courtesy: KenGen
A Technology Breakthrough
Sosian’s condensed timeframe is especially stunning given that traditional geothermal development can exceed seven years. This is owing in part to a complex process that involves drilling and testing multiple wells, selecting a centralized power plant location, ordering steam turbines, and constructing extensive steam collection and reinjection systems. The traditional approach is also ridden with risks, including significant delays and inefficiencies, such as energy losses from steam pressure drops, thermal losses over long distances, and the underutilization of wells with varying pressures.
Sosian, to some measure, had the benefit of the GDC’s public-private partnership model for developing Menengai, under which the GDC assumes upfront risks of geothermal development. The state company has also notably set out to develop the field in five phases, starting with a 105-MW “steam sales” model, where it supplies steam from drilled wells to the power plants via a 25-km steam gathering and piping system. As of 2023, GDC had drilled 53 wells with a potential of 169 MW.
However, the power plant’s success can also be attributed to a distinctive new geothermal development process introduced by China’s Kaishan Group. Dr. Tang Yan, general manager of Kaishan Group, recalled realizing the need for a dramatic shift at a 2015 geothermal conference in Melbourne, Australia, where experts discussed the pitfalls of conventional methods. “I said, ‘Why don’t you put a power plant on the wellhead and do it phase by phase?’ ” he recounted.
Overcoming Traditional Challenges
While the approach proposed to support incremental power production from the start while providing revenue to support future project expansion, Yan learned no technology to support the approach was commercially available. Kaishan, which had then already begun its transition from a giant Shanghai-headquartered air compressor maker to a diversified global company, jumped into action to leverage its 2012-developed Organic Rankine Cycle (ORC) expander and screw steam expander technologies.
The technologies—originally developed for waste heat recovery from refineries and steel mills—allowed Kaishan to optimize geothermal power generation by maximizing energy output from varying well conditions, reducing inefficiencies, and enabling the development of four types of decentralized, modular power plants that are quicker to deploy and more adaptable to different geothermal fields, Yan told POWER. “These modular power plants include the steam screw expander modular power plants, the steam ORC modular power plants, the brine ORC modular power plants, and the steam and brine dual resource modular power plants,” he explained.
Steam screw expanders are specifically designed to handle wet or saturated steam, which is common in geothermal wells, effectively extracting energy from a wider range of well conditions, including wells with high non-condensable gas (NCG) content that may not be suitable for traditional turbines. ORC systems, meanwhile, are adept at converting lower-temperature steam and brine—byproducts that would otherwise go to waste—into additional electricity, Yan said.
In addition, Kaishan’s modular plants can be used to form hybrid cycles or thermal systems to meet any production well conditions, maximize their power output, and eliminate low-head pressure (WHP) wasted wells or idling wells. Because the technologies can be adapted to specific geothermal resource conditions at different project sites, they can be tailored to provide stellar efficiency, he said. “We can improve the well thermal efficiency of, for example, medium enthalpy wells, to up to 18% and 19%,” he said. That compares to only 8% to 12% for traditional centralized power plants that only use single-flash steam, he noted.
he 35-MWe Sosian Menengai Geothermal Power plant was commissioned in August 2023. The plant uses two Kaishan geothermal steam counterpressure screw expanders, which discharge their exhausts into three Organic Rankine Cycle units. Courtesy: Kaishan Group
A Competitive Edge for New Geothermal Power
Kaishan quickly expanded the niche technology into a lucrative business. Since it put online the first of four phases of the 240-MW Sorik Marapi Geothermal Project in Indonesia in 2018, it has built the 10-MW Sokoria Geothermal, also in Indonesia, alongside projects in Turkey, the U.S., and Hungary. At Sosian, Kaishan’s first project in Kenya, the company served as the engineering, procurement, and construction (EPC) contractor.
According to Yan, Kaishan’s cost-effective price point proved a crucial selection advantage. Kaishan’s EPC contract is valued at $65 million, compared to a $108 million EPC contract recently awarded for Menengai II, one of the region’s three equally sized IPP projects. The price difference is rooted in the technology selection, Yan explained. While Sosian’s 35-MW project was designed as a centralized power plant, it is powered by two steam screw expanders and three wet steam ORC modular power plants.
However, GDC’s steam contains 3.3% NCG—which represents a “huge percentage,” he said. If Sosian used traditional steam turbines, they would need to expand steam at 6 bar absolute and then consume more then 30 tons of steam per hour to remove NCG using steam injectors and vacuum pumps. Instead, Sosian employs steam screw expanders and a bottom cycle to handle the saturated steam discharge, reducing the steam to atmospheric levels throughout the entire process while eliminating the parasitic power typically consumed by vacuum systems.
“The overall efficiency compared to a traditional steam turbine is a huge game changer for this site,” Yan said. “The project only needed a guarantee of 33.25 MW, and the target was 35 MW, but we’re actually generating 37 MW.” At the same time, the project doesn’t need to purchase the extra 10% of steam for a steam injector, putting less of a burden on the GDC, he said.
A Solution for Idled Wells
The modularity of the system also proved beneficial to speed up construction and, crucially, to overcome supply chain and project management challenges posed by the COVID pandemic, Yan said. Kaishan typically assembles the modules and conducts component testing in a factory setting over six to nine months, he said. “And then, when we ship to the site, usually it takes a very short time to put them together, and you don’t need to do any welding on the power modules,” he added. “That’s sometimes where quality control can be a challenge,” he noted.
The success of the Sosian Menegai project has so far sparked significant interest in Kenya’s geothermal industry, Yan said. A key reason is that Kenya has a lot of wells, and an estimated 25% to 30% of those wells may not be supported by a steam collection system, which is needed by centralized steam turbines. “They call them idled wells or wasted wells, and they sit there and do nothing,” even if it was costly to drill them, he said. “But our technology doesn’t have that limitation because we can use any good pressure, whether they can produce brine or steam.”
—Sonal Patel is a POWER senior editor (@sonalcpatel, @POWERmagazine).
中文翻译稿
？榛⒌绯д谔岣呖夏嵫堑厝刃
调试阶段的 Sosian Menegai 。图片泉源：ag亚娱集团集团
肯尼亚最新的地热发电厂 Sosian Menengai 地热发电厂接纳 ？榛忠 ，可最大限度提高效率、降低本钱并增强可扩展性 。
肯尼亚景物秀丽的裂谷地区是地热资源的宝库 ？夏嵫橇压仁橇衫东非大裂谷系统 (EARS) 的一部分 ，东非大裂谷系统是一个长达 6,400 公里的地质结构分叉 ，将非洲大陆一分为二 ？夏嵫橇压刃纬闪艘桓霰手弊呃 ，其中有麋集的断层和火山运动、温泉、喷气孔和硫磺渗透的裂痕 。只管肯尼亚在 20 世纪 50 年月就最先举行地热勘探以开发电力 ，但其大部分投资都集中在位于地狱之门国家公园内的奥尔卡里亚地区 ，该公园靠近纳库鲁县火烈鸟遮掩的纳瓦沙湖 。奥尔卡里亚的六座地热发电站中有五座归 KenGen 所有（总容量为 799 兆瓦） ，而总部位于内华达州的 Ormat Technologies拥有一座 150 兆瓦的发电站 。到 2023 年 ，奥尔卡里亚 (Olkaria) 电厂将提供肯尼亚近 45% 的总发电量 ，为这个东非强国仅有的 3.3 吉瓦的装机容量做出了重大孝顺 。
2008 年 ，地热开发公司 (GDC) 将重点扩大到奥尔卡里亚以北的梅嫩盖地区 ，该地区是一座重大的盾形火山 ，拥有天下上最大的火山口之一 。地热开发公司是一家国有特殊目的公司 ，其使命是加速该国的地热资源开发 。GDC 体现 ，梅嫩盖综合体蕴藏着 1,600 兆瓦的地热潜力 ，但其恒久目的是开发 465 兆瓦的地热蒸汽当量 。
2013 年 ，该集团迈出了第一步 ，通过竞争方法将该综合体中的前三个 35 兆瓦发电项目授予三家自力电力供应商 (IPP)：Orpower 22（前身为纽约 Symbion 公司的子公司 ，现归中国ag亚娱集团集团所有）、总部位于南非的 Quantum Power East Africa（现由英国公司 Globeleq 控股）和总部位于内罗毕的 Sosian Energy 。2023 年 8 月 ，这些项目中的第一个项目——Menengai III（现正式称为 Sosian Menengai 地热发电项目）竣事了为期 16 个月的建设工期 ，并最先向电网运送第一批电力 。
地图显示了肯尼亚裂谷沿线地热区的位置 。图片泉源：KenGen
手艺突破
鉴于古板地热开发可能要耗时凌驾七年 ，Sosian 的缩短工期尤其令人震惊 。这在一定水平上归因于一个重大的历程 ，包括钻探和测试多个井、选择集中发电厂位置、订购蒸汽涡轮机以及制作普遍的蒸汽网络和再注入系统 。古板要领也充满危害 ，包括严重的延误和效率低下 ，例如蒸汽压力下降造成的能量损失、长距离热损失以及压力转变的井的使用缺乏 。
在某种水平上 ，Sosian 受益于 GDC 开发 Menengai 的公私相助模式 ，凭证该模式 ，GDC 肩负地热开发的前期危害 。值得注重的是 ，这家国有公司还妄想分五个阶段开发该地热田 ，首先接纳 105 兆瓦的“蒸汽销售”模式 ，通过 25 公里长的蒸汽网络和管道系统将钻井中的蒸汽供应给发电厂 。阻止 2023 年 ，GDC 已钻探了 53 口井 ，潜力为 169 兆瓦 。
然而 ，该发电厂的乐成也归功于中国ag亚娱集团集团推出的奇异的新型地热开发工艺 g亚娱集团集团总司理汤炎博士回忆说 ，他在 2015 年澳大利亚墨尔本举行的地热聚会上意识到需要举行重大转变 ，其时专家们讨论了古板要领的缺陷 。“我说 ，‘你为什么不在井口建一个发电厂 ，分阶段举行呢 ？’”他回忆道 。
战胜古板挑战
虽然该要领从一最先就提出支持增量发电 ，同时提供收入以支持未来的项目扩展 ，但汤炎博士相识到 ，没有支持该要领的手艺可供商业使用 g亚娱集团其时已经最先从一家总部位于上海的大型空气压缩机制造商转型为一家多元化的全球性公司 ，并连忙接纳行动 ，使用其 2012 年开发的有机朗肯循环 (ORC) 膨胀机和螺杆蒸汽膨胀机手艺 。
汤炎博士告诉《POWER》杂志 ，这些手艺最初是为接纳炼油厂和钢厂的废热而开发的 ，它使ag亚娱集团公司能够通过最大限度地提高差别井况下的能量输出、镌汰低效率 ，以及开发四种类型的疏散式 ？榛⒌绯Ю从呕厝确⒌ ，这些发电厂安排速率更快 ，更能顺应差别的地热田 。 “这些 ？榛⒌绯Оㄕ羝莞伺蛘突 ？榛⒌绯А⒄羝 ORC ？榛⒌绯А⒀嗡 ORC ？榛⒌绯б约罢羝脱嗡试茨 ？榛⒌绯 ，”他诠释说 。
蒸汽螺杆膨胀机专门设计用于处置惩罚地热井中常见的湿蒸汽或饱和蒸汽 ，可有用从种种井况中提取能量 ，包括可能不适合古板涡轮机的不凝性气体 (NCG)含量高的井 。与此同时 ，ORC 系统善于将低温蒸汽和盐水（不然这些副产品将被铺张）转化为特另外电能 ，汤炎博士说 。
别的 ，ag亚娱集团的 ？榛绯Э捎糜谛纬苫煜坊蛉攘ο低 ，以知足任何生产井条件 ，最大限度地提高其发电量 ，并消除低压 (WHP) 铺张井或闲置井 。他说 ，由于这些手艺可以顺应差别项目所在的特定地热资源条件 ，因此可以量身定制以提供卓越的效率 。他说：“我们可以将中焓井的热效率提高到 18% 和 19% 。”他指出 ，相比之下 ，仅使用单次闪蒸蒸汽的古板集中式发电厂的热效率仅为 8% 至 12% 。
35 MWe 的 Sosian Menengai 地热发电厂于 2023 年 8 月投入使用 。该电厂使用两台ag亚娱集团地热蒸汽反压螺杆膨胀机 ，将废气排放到三个有机朗肯循环装置中 。图片泉源：ag亚娱集团集团
新地热发电的竞争优势
ag亚娱集团迅速将这项小众手艺拓展为一项利润丰富的营业 。自2018 年在印度尼西亚投产 240 兆瓦 Sorik Marapi 地热项目四期工程中的第一期以来 ，该公司已在印度尼西亚制作了 10 兆瓦的 Sokoria 地热项目 ，别的还在土耳其、美国和匈牙利开展了项目 。Sosian是ag亚娱集团在肯尼亚的第一个地热项目 ，公司担当工程、采购和施工 (EPC) 承包商 。
汤炎博士体现 ，ag亚娱集团电厂具有本钱效益的价钱点是其要害的选择优势 g亚娱集团电厂的 EPC 条约价值 6500 万美元 ，而该地区三个一律规模的 IPP 项目之一 Menengai II 最近获得的 EPC 条约价值 1.08 亿美元 。汤炎博士诠释说 ，价钱差别的泉源在于手艺选择 。虽然 Sosian 的 35 兆瓦项目设计为集中式发电厂 ，但它由两个蒸汽螺杆膨胀机和三个湿蒸汽 ORC ？榛⒌绯峁┒ 。
然而 ，GDC 的蒸汽含有 3.3% 的 NCG ，这是一个“重大的百分比” ，他说 。若是 Sosian 使用古板的蒸汽轮机 ，他们需要将蒸汽膨胀至 6 bar 绝对压力 ，然后每小时消耗凌驾 30 吨的蒸汽 ，使用蒸汽喷射器和真空泵去除 NCG 。相反 ，Sosian 使用蒸汽螺杆膨胀机和底部循环来处置惩罚饱和蒸汽排放 ，在整个历程中将蒸汽降低到大气水平 ，同时消除真空系统通常消耗的寄生功率 。
“与古板蒸汽轮机相比 ，整体效率关于该站点来说是一个重大的改变 ，”汤炎博士说道 。“该项目只需要包管 33.25 兆瓦 ，目的是 35 兆瓦 ，但我们现实上发电量为 37 兆瓦 。”同时 ，该项目不需要特殊购置10%的蒸汽用于蒸汽喷射器 ，从而减轻了GDC的肩负 ，他说 。
闲置地热井的解决计划
汤炎博士体现 ，该系统的 ？榛杓埔灿欣诩铀偈┕に俾 ，更主要的是 ，有助于战胜新冠疫情带来的供应链和项目治理挑战 。他说 ，ag亚娱集团通 ；嵩诹骄鸥鲈碌氖奔淠谧樽澳 ？椴⒃诠こ樾沃芯傩凶榧测试 。“然后 ，当我们运送到现场时 ，通常只需很短的时间即可将它们组装在一起 ，并且您无需对电源 ？榫傩腥魏魏附 ，”他增补道 。“有时 ，质量控制可能是一个挑战 ，”他指出 。
他还说 ，Sosian Menegai 项目的乐成迄今已引起人们对肯尼亚地热工业的极大兴趣 。一个要害缘故原由是肯尼亚有许多井 ，预计其中 25% 到 30% 的井可能没有蒸汽网络系统 ，而蒸汽网络系统是集中式蒸汽涡轮机所必需的 。“他们称这些井为闲置井或放弃井 ，它们就放在那里 ，什么也不做” ，纵然钻探这些井的本钱很高 ，“但我们的手艺没有这种限制 ，由于我们可以使用任何优异的压力 ，无论它们是爆发盐水照旧蒸汽 。”
— Sonal Patel 是 POWER 的高级编辑（@sonalcpatel, @POWERmagazine）