Что могут ответить девелоперы на призывы Греты Тунберг
Главный тезис Парижского соглашения — предотвращение роста температуры воздуха на планете более чем на 2 °С. В повестке конференции по изменению климата СОР 21 в декабре 2015 года была высказана дополнительная инициатива от десяти стран. Она предполагает, что к 2030 году нейтральными по выбросам углерода станут все новые здания, а к 2050-му — все здания в мире.
Актуальность проблемы подтверждена прошедшим 23 сентября 2019 Глобальным саммитом действий по климату в штаб-квартире ООН, на котором с своим призывом выступила экоактивистка Грета Тунберг. Сейчас эту инициативу поддерживают 63 подписанта, которые обязуются снизить выбросы СО₂ в секторе недвижимости и строительства на 84 гигатонны. В числе участников «углеродного нейтралитета» 31 компания и организация, шесть стран и регионов, 26 городов. Инициатор, координатор и вдохновитель реализации углеродной нейтральности зданий — Всемирный совет по экологическому строительству, World Green Building Council (WorldGBC).
История Всемирного совета и глобального неправительственного движения за устойчивое развитие начинается учредительным собранием в 1999 году, в котором участвовала и Россия. Тогда восемь стран, наиболее обеспокоенных триедиными экологическими, социальными и экономическими проблемами, официально учредили новую организацию. Всемирный совет начал свою деятельность в 2002 году, но Россия не была среди учредителей и оформила официальное членство лишь в 2009-м.
Еще одно фирменное блюдо WorldGBC с 2009 года — это Всемирная неделя экологического строительства, World Green Building Week. Она проводится сразу после дня осеннего равноденствия и в этом году пришлась на 23–29 сентября. Каждый год предлагается новая актуальная тема в области устойчивого развития.
Сегодняшняя тема — изучить, продемонстрировать, повысить осведомленность о выбросах углерода на всех стадиях жизненного цикла зданий и способствовать внедрению новых практик и нового мышления для снижения эмиссии парниковых газов. Акцент прошлого года — «зеленые» здания. В поддержку инициативы люди публиковали в социальных сетях фотографии с хештегом HomeGreenHome. Ранее в фокусе были здания с нулевыми выбросами — в 2017 году, изменение перспектив — в 2016-м, позитивные изменения — в 2015-м, прямые действия — в 2014-м, здоровье людей — в 2013-м, здания и сообщества — в 2012-м.
В странах — участницах Всемирного совета, а сейчас их 68, в рамках «зеленой» недели заявлено 110 мероприятий на разных уровнях. Главное событие недели — презентация доклада «Предупреждая содержание углерода» (Bringing Embodied Carbon Upfront). Данный доклад WorldGBC призывает к значительному сотрудничеству в строительной отрасли для достижения целей декарбонизации (снижения выбросов), раскрывает стратегические перспективы, ставит цели и предлагает действия и ключевые этапы и рассказывает об индустриальных лидерах-первопроходцах.
В этом году климатические саммит и неделя в Нью-Йорке проходили совместно с Генеральной ассамблеей ООН. Всемирный совет предлагает увязать тему климата, «зеленых» зданий и экологического строительства напрямую с 11 из 17 целей устойчивого развития ООН в формулировке WorldGBC:
В последние годы Россия активно эксплуатирует «зеленую» тему. Проведены два тематических года: Год охраны окружающей среды в 2013-м и Год экологии в 2017-м. Олимпиада в Сочи и чемпионат мира по футболу — 2018, кроме политики и спорта, соревновались в экологичности. Созданы российские и применяются международные «зеленые» стандарты.
Экопроблемы вписываются в повестку крупных мероприятий, включая новые: мусор и свалки, пожары и вырубки леса, обмеление рек, таяние вечной мерзлоты, нездоровая застройка. Дополнительно регулярно проводятся несколько специализированных климатических, экологических, урбанистических и строительных форумов. Сформировалась целая когорта 3D-активистов устойчивого развития, которые Докладывают, Дискутируют и Делают. Очень мало последних. Совсем мало тех, кто совмещает все три ипостаси.
За десять лет организованного движения экологического строительства в стране нам удалось развить его определение от однобокой трактовки, заключающейся в образе деревянного здания с зеленой крышей на берегу реки, до комплексного видения, в центре которого — «зеленые» стандарты.
На мой взгляд, за следующие десять лет произойдет переход от экологических стандартов к устойчивым технологиям. Не только цифровым и хай-тек, как это было на первых этапах, но и социальным, образовательным, наукоемким, выгодным всем и во всем. Как пример — некомпрессионное и нефреоновое кондиционирование; опреснение, очистка и получение воды из воздуха, снижение потребления, потерь и рекуперация энергии; уменьшение выбросов углерода и отходов, захват СO₂ из воздуха и его повторное использование, новые виды альтернативной энергии, технологии в недвижимости для здоровья и благополучия людей.
Идеей Недели экологического строительства прошлого года была акция с плакатами, на которых люди писали и фотографировали свои обещания — как они сделают свои дома зеленее, здоровее, лучше. Было много разных клятв, но победит обещание каждую из идей воплотить в жизнь.
What is Embodied Carbon?
Embodied carbon is the carbon dioxide (CO₂) emissions associated with materials and construction processes throughout the whole lifecycle of a building or infrastructure.
It includes any CO₂ created during the manufacturing of building materials (material extraction, transport to manufacturer, manufacturing), the transport of those materials to the job site, and the construction practices used.
Put simply, embodied carbon is the carbon footprint of a building or infrastructure project before it becomes operational. It also refers to the CO₂ produced maintaining the building and eventually demolishing it, transporting the waste, and recycling it.
Embodied carbon is distinct from operational carbon — the carbon that comes from energy, heat, lighting, etc. Thanks to advances in reducing operational carbon, recent data from the World Green Building Council indicates that embodied carbon is becoming a larger portion of a building’s overall carbon footprint.
Why Embodied Carbon is a Focus in Construction
The world’s building stock is expected to double by 2060 — that’s equivalent to adding an entire New York City to the planet every month for the next 40 years.
This is good news for concrete producers. However, without some changes in how we produce concrete, it’s bad news for climate change. Cement — the key ingredient that gives concrete its strength — is also one of the largest emitters of CO2 in the built environment.
Since concrete is the most abundant human-made material in the world, cement production creates
7% of the world’s CO2 emissions and is the largest contributor to embodied carbon in the built environment.
Tackling Embodied Carbon
Embodied carbon is expected to account for nearly 50% of the overall carbon footprint of new construction between now and 2050.
To address embodied carbon, a number of organizations including Architecture 2030, Structural Engineers 2050 Challenge (SE2050), the Carbon Leadership Forum, and the World Green Building Council have jointly taken on a mission to eliminate embodied carbon from buildings by the year 2050.
One of the simplest ways to move the needle on embodied carbon is to change the way concrete is specified. Watch our on-demand webinar, The Case for Performance-Based Concrete Specs, to learn more.
Continuing the rapid development of the timely and industry leading Embodied Carbon assessment feature-set in Tekla Structural Designer, this release adds two further Embodied Carbon Overview table grouping options of by Material and by Construction Type & Material, plus separate reporting of totals for mat slabs and other concrete slabs. These enhancements are specifically targeted at facilitating interaction with the Institute of Structural Engineer’s (IStructE) Structural Carbon Tool spreadsheet, enabling much of Tekla Structural Designer’s embodied carbon data to be copied and pasted directly into the IStructE sheet (all Tekla Structural Designer’s Embodied Carbon tables can be exported directly to Excel from the Tabular Data view).
In addition to these enhancements, a new Chart view has been added for Embodied Carbon by Material and the Embodied Carbon Factors (ECF) for Westok beams have been revised and updated. The full list of enhancements in this area is as follows with further details for each below:
Group by Material
There is a single total for each material.
Group by Construction Type & Material
An example of this new table option is shown in the picture below for the same model. Note the following:
Hence the steel total is separated for beams, composite beams, columns, braces, etc
Separated Reporting of Slabs and Mats
New “Embodied Carbon by Material” Chart
A new automated “Embodied Carbon by Material” chart option has been added to the Charts View as shown in the picture below left. Note the following:
In this view, materials with the same name but different carbon factors are combined (the chart shown below right is for the same steel structure with steel decking composite slabs and composite and non-composite beams used for examples above).
Revised Embodied Carbon Factors (ECFs) for Westok
ECFs for Westok sections are revised in this release as follows:
The Westok process adds 60 kgCO2e/t to the A1 to A3 stage embodied carbon
60 kgCO2e/t = 0.06 kgCO2e/kg
The existing value in the UK Settings was 2.49 kgCO2e/kg
2.45 kgCO2e/kg is the default for rolled sections
0.04 kgCO2e/kg was the previous addition used for the Westok process, based on information previously received from Westok
The new value used is 2.45 + 0.06 = 2.51 kgCO2e/kg
Note that the new value is provided in the new settings file for this release, so for an existing installation you will need to re-import the settings for this value to be updated. The method of doing this is detailed in the 2021 Release Notes for the Embodied Carbon feature here (see the “Existing Installations” bullet point in the section on Embodied Carbon Factors).
Embodied carbon is changing the buildings conversation
It’s time for us to rethink the process of designing buildings. We must commit to using embodied carbon analysis to drive design decisions
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This article first appeared as “It’s all about embodied carbon” in the Stantec Design Quarterly, Issue 10.
Until recently, much of the conversation about sustainability in the buildings industry was centered around operational carbon. That’s the carbon emitted by buildings or the energy buildings consume in their day-to-day operations.
We approached sustainability as a matter of energy performance—of reducing that appetite. The goal was to design an energy-efficient building so that on day one that appetite was lower and so were the utility bills. That approach shaped state energy efficiency codes such as Title-24 in California, Seattle Energy Code, the ASHRAE Standards, and green-building certifications such as LEED, Living Building Challenge, and Green Globes.
The mantra was design or engineer a building so that from day one it uses less energy to operate.
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Associate, Senior Sustainability Consultant
Design Quarterly
Read and download Stantec’s Design Quarterly Issue 10 | The Carbon Issue
As we analyze buildings for their embodied carbon, it’s clear there are opportunities to design differently. (Royal Columbian Hospital Phase 1 in New Westminster, British Columbia)
What is embodied carbon?
Reducing the operational energy needs of buildings makes sense and will continue to be an essential part of solving the climate change crisis. What we missed by only considering operational energy was the energy investment in the building that it inherits right from day one—its embodied carbon or embodied energy.
Simply put, what volume of carbon emissions did that building contribute to the atmosphere—the air we breathe—before it even opened?
We define embodied carbon as the greenhouse gas emissions (in carbon dioxide equivalent) attributed to manufacturing and transportation of construction materials and the process of construction. Unlike the building systems, which can be replaced with more efficient ones and improved over time, this embodied carbon amount is fixed once it’s been spent. In essence, we (and the planet) live forever with the decisions that the whole project team—from designer to contractor to client—make when designing the original building. A groundswell of interest in embodied carbon from the design industry and the public at large has resulted in the availability of more information about materials and their origin as well as an increasing range of alternative, naturally derived materials.
Climate crisis, new look at carbon
The climate crisis has forced our hands to act. Science tells us that if we keep on emitting carbon dioxide as business as usual then within the next 10 years, the global temp will rise 1.5° Celsius—and that rise will be irreversible. At the next milestone, a rise of 2°C, we’ll see catastrophic changes in the climate.
Recent reports from the Intergovernmental Panel on Climate Change sternly recommend zero carbon emissions globally by 2050 to stall temperature increase. To target zero emissions, we need a “carbon budget” for the planet. This budget is the max carbon that people can consume annually to keep us on track to phase out carbon emissions by 2050. The lower the carbon budget, the better our chances are of stalling temperature increases. To stall the 1.5°C rise, our carbon budget for the planet is 340 Gt CO2. This carbon budget has a 67% probability to stall the 1.5°C rise and keep us on track to phase out carbon emissions.
Buildings operations accounts for 28% of the global carbon bill. Buildings infrastructure/ materials account for 11% total annual global emissions by sector. Making the steel, concrete, and glass for buildings and transporting them to the site consumes a lot of energy. Our longtime focus on operational carbon has resulted in the possibility of a lopsided carbon footprint for an energy-efficient building. Embodied carbon might account for 66% of the total carbon footprint of a new energy-efficient building with a building life cycle of 30 years.
We’ve come a long way in terms of what’s possible in operational efficiency. But looking at the lifecycle of a building, we now see that there’s a lot more we can do. Something has got to change. When we begin to analyze buildings for their embodied carbon, it’s clear there are opportunities to design differently.
Take concrete, for example
A whopping 8% of global emissions come from the fiery kilns that manufacture cement and concrete, of which Portland Cement Concrete is the most common. This is global phenomena. It’s an extremely energy intensive process to make concrete and the world makes a lot of it.
Fly ash is a byproduct of the cement-manufacturing process and used to be thrown away. But in fact, it has similar binding properties to cement with the right aggregates. And it turns out if we add fly ash back into the cement mix—using 50-60% fly ash instead of 100% Portland cement with aggregates—we can significantly reduce the carbon emissions associated with manufacturing. Studies say adding fly ash reduces the water required to make cement and results in a more workable, pumpable, and stronger concrete product.
Common-sense approaches like this, driven by an awareness of embodied carbon, are going to help us meet our carbon goals as an industry. Similarly, steel manufactured from electric arc furnaces has much lower embodied carbon than that made from a basic oxygen furnace.
Locking up carbon
Broadly speaking, we must look at various ways to sequester carbon—lock up CO2 out of the atmosphere. Innovative technologies such as low carbon concrete, which injects carbon into the concrete mix, promise some sequestration. Another approach is using cross-laminated timber (CLT), where pieces of wood are pressed together to create a super strong timber building material. It’s one of the most promising developments for those interested in designing with embodied carbon in mind. CLT is strong enough that we can use it in buildings over 10 stories. It is procured from managed, sustainable forests and leftover wood scraps. Even accounting for the glue, manufacturing, and transport, CLT is a clear winner.
Just like CLT, natural and biobased materials can lock up CO2. For interiors, this means choosing natural, renewable, and biobased materials like bamboo, cellulose, cork, wood-fiber board, insulation with waste denim, and linoleum. Even straw bales for insulation has benefits regarding embodied carbon. Hempcrete, an innovative product combining the hemp plant core with concrete is strong, elastic, and sequesters carbon.
The 2021 SP2 release features the following further enhancements for Embodied Carbon calculation and reporting:
Reporting by level
Following customer feedback and requests, the Embodied Carbon Overview is enhanced to meet the requirement for a report that includes all items between one level and another, improving the reporting of the Embodied Carbon Mass (ECM) on a by level basis.
Thus for example, the Level St. 1 report row will include everything above foundation level up to and including items in Level 1, and so on, as illustrated in the picture below.
Note that this new feature works together with the Level Property “Reporting Level” shown above left, which is enabled by default for levels set as Floors. However it can be checked off e.g. where for some modeling reason many closely spaced floor levels have been defined. Note the following:
The “Reporting Level” setting applies to other summary reports such as the drift checks.
Previously this setting was called “Check for drift” which was sometimes misinterpreted as a control that switched checks on and off.
Note the following:
As expected items that exist in the identical level planes have identical ECM (e.g. the composite slabs)
Note that items which exist between the planes are also assigned to a level:
E.g. column stacks, braces and wind walls
these can be different at each level
Items that exist between reporting levels are assigned to the level above:
E.g. the top story braces and top stacks of columns are assigned to level 3.
Wind Walls are split and shared between levels as appropriate.
The floored area is the total area of slab items included in the level total (not necessarily all in a single plane)
The picture below shows the report for the same building after switching off the “Reporting level” checkbox at Levels 1 and 3. Note the following:
Everything that was in St.1 and St.2 is now combined in the St.2 totals
St.2 becomes the highest designated reporting level. However everything above that level must be assigned to something so a “Top” level is used for that.
Reporting for piles
To enable this the Pile Catalogue data is enhanced with a new Material page as shown in the picture below. Note particularly the following settings:
This option is included since there are many and varied piling systems. While a theoretical diameter and length is specified, in practice these can be minimums or approximations. Hence this setting enables an adjustment to be made to cater for different systems e.g. an in-situ under-reamed piling system might be given an adjustment >> 100%
There are then two basic options for applying ECF’s to piles:
Interoperability of Pile Data
The new Pile material properties and Embodied Carbon values are also included in a number of interoperability methods as follows:
Pile material and grade is included on export (previously it was set to same grade as related pile cap / mat)
Embodied carbon values are also exported. These can then be reviewed in the BIM application, e.g. as shown in the picture below for Tekla Structures the information is populated to the object’s TSD values which can be viewed via Inquire Object and included in Tekla Structures entity labels and output.
Pile material, grade and type are also considered when updating an existing Tekla Structural Designer model and importing to a new model file.
Pile material and grade is included
Pile material and grade is added to the One Click LCA export data/ Report.
Reinforcement information is also added where applicable.
