Advertisements
Does the Sahara desert hold the key?

Does the Sahara desert hold the key?

Should we turn the Sahara Desert into a huge solar farm? Bigger than North America and without the obstacles of wildlife or people, setting up power stations across the desert could give the world a clean, renewable future. So why hasn’t it been done already, asks Steven Cutts whilst wondering: Does the Sahara desert hold the key to unlocking unlimited solar power?

Does the Sahara desert hold the key?
Solar power from only one to two per cent of the Sahara could provide electricity for the whole of Europe ( Getty/iStock )

There are some problems we never seem able to solve. The shortage of electrical power is one of them. Ever since President Carter proclaimed an energy crisis in the 1970s, people have been talking about all kinds of weird and wonderful solutions to the issue of energy and – thus far – no one has come up with one single answer.

While solar power is now providing as much as 4 per cent of British electricity, few people appreciate just how quickly electricity production will have to increase. If the internal combustion engine is on its way out then the western world will need to double its electrical supply just to recharge its battery-powered vehicles.

Progress on this scale demands a fundamental rethink of our entire energy supply industry. The beginning of the 21st century saw a group of German engineers doing just that. They developed a plan to harvest solar power in the Sahara desert and transmit the stuff across the Mediterranean using very high-voltage, direct-current cables.

Just as Carter had been influenced by the oil shock of 1973, the Germans had been influenced by the disaster in Chernobyl and a mounting recognition that all technology is associated with risk. At that stage, large scale solar power plants still sounded like science fiction but the potential of solar power had long been recognised.

One German engineer calculated that the amount of solar energy absorbed by the world’s deserts exceeds the total amount of energy consumed by man in an entire year. We’d only need to harness a small proportion of this energy to provide us with all the electricity we are likely to need without any of the usual headaches surrounding pollution or fuel supply.

The Sahara is a vast area of land, larger, even, than the continental United States and extending over several national boundaries. It would take only one or two per cent of the land here to provide the whole of Europe with electrical power. There isn’t a lot of wildlife to destroy in the desert and since the population density is close to zero, we can probably avoid the nimbyists too.

Does the Sahara desert hold the key?
Workers install solar panels at the Enel Green Power photovoltaic plant in the desert near Villanueva, Mexico (AFP/Getty)

At first sight, though, the Sahara isn’t quite as perfect since much of the land here is still some distance north of the equator. As we approach the equatorial regions of the world, it seems logical to assume that the intensity of sunlight ought to go up. However, the equatorial region of the planet is associated with a much higher level of cloud cover than the Sahara and on balance, about 20 to 30 degrees north of the equator turns out to be the ideal location for a large scale solar power plant.

Plenty of land, plenty of sun, not a lot of cloud and not that far from the nearest major market for electrical power, western Europe.

Some manufacturers are now producing photovoltaic panels that are cosmetically indistinguishable from traditional roofing tiles. It’s easy to envisage a future where it becomes compulsory

Many of the nation states in the region are quite poor with little or nothing in the way of oil or gas reserves. Ever since the 1970s, countries with significant oil reserves have been able to cash in on the oil boom and increase its standard of living overnight, whereas a nation that lacks oil reserves is forced to import at potentially enormous cost. Thus far, this kind of prosperity has been based on geological accident, but solar power is different. Soon, relatively poor countries might have access to a major energy resource of their own, enabling them to generate their own power at home and to export anything left over to western Europe.

So why isn’t it happening?

Part of the appeal of large-scale solar power generation is the opportunity it provides for a secure energy supply. Ever since the early 1970s, western governments have been living in fear of another Opec crisis or – at the very least – some sort of military and political confrontation that might interrupt the supply of energy. When we try to calculate how many lives might be lost or damaged by one source of energy or another, we really ought to factor in how many lives we’d be likely to lose by fighting another war for oil. Politicians who are too young to remember the Yom Kippur War are old enough to understand Putin and the fear that he might try to suddenly cut off the supply of natural gas to western Europe as part of some alternative economic warfare. What will Nato actually do if that happens?

During the 1970s energy crisis, a three-colour flag system was used to denote gas availability at service stations in the US (Rex)

But our friction with the Middle East goes back even further than Yom Kippur. A generation older than my own has not forgotten the Suez Crisis. During the 1950s, the Egyptian president Gamal Abdel Nasser decided to seize the Suez Canal and nationalise the entire project. The countries, companies and investors who had paid for its construction were far from pleased. Attempts at recapturing the canal ended in fiasco. The Egyptians came out of the 1950s quite well.

Against this is the relentless march of progress and the emergence of new tech that has thrown the whole equation into disarray. Just 10 years ago, the environmental movement was obsessed with the idea that western governments should continue to subsidise solar power. In those dim and distant days, solar power was so costly that people had to be bribed to actually use it. This is no longer the case and governments believe that it is entirely reasonable to phase out their solar power subsidies. Whilst this decision may be premature, it’s hard to ignore just how quickly the price of a photovoltaic panel has fallen. Part of the reason for this is mass production and part is the Chinese desire to subsidise their own industry, effectively destroying their competitors.

Does the Sahara desert hold the key?

Panels are falling in cost so rapidly that it is not unreasonable to suggest that we should delay buying them just to wait for the next major price fall. Some manufacturers are now producing photovoltaic panels that are cosmetically indistinguishable from traditional roofing tiles. It’s easy to envisage a future where it becomes compulsory for all new housing to be built with a photovoltaic roof. Given that Britain turns over about 1 per cent of our housing stock every year, it also isn’t difficult to envisage a future where the majority of homes in the country are self-sufficient in energy.

But if the vogue towards a cheap and efficient energy-powered future continues, people are bound to look at the Sahara again. A vision of the desert practically covered in solar power panels is now a reality with a number of projects already having been established in North America and north Africa.

There are already accusations that North African Solar Power represents a rebirth of colonialism with European powers attempting to snatch resources from Africa and seize it for themselves

Engineers in Morocco have built one of the most ambitious solar energy projects on the planet. Using Spanish technology, they have built a system of mirrors designed to reflect the sun’s rays onto a large box that has been placed on a pedestal in the centre of the solar farm. This kind of energy generation is different from photovoltaic panels. It requires moving parts and a different attitude, but it has advantages too.

The mirrors are placed on rotating platforms so they can move throughout the day to follow the sun. By synchronising the position of each mirror to the day-night cycle, the maximum possible energy can be directed at one point. That point is a box containing salt. The salt soon melts into a sort of man-made lava and can be moved as a fluid along pipes where it is used to heat water, which in turn generates steam. The steam can then drive turbines creating electricity. This kind of installation involves multiple moving components and would require more maintenance than a standard PV panel. However, the molten salt can remain hot well after sundown and continue to generate electricity for up to seven hours into the night. Given that a country like Morocco would typically experience about 12 hours of daylight, this still leaves the problem of the energy gap in the early hours of the morning while the system waits for the new dawn, but it’s much more comprehensive than PV. This kind of technology uses a lot of water for cooling purposes and this might restrict its use. But it’s already quite popular and a number of such systems have been built in the United States.

Does the Sahara desert hold the key?
An ambitious solar project in Morocco has devised panels that move with the sun throughout the day (AFP/Getty)

This kind of vision requires us to believe that it might be possible to transmit energy over vast distances. Electricity is pretty ephemeral stuff; it doesn’t lend itself to long-distance transportation. In complete contrast, crude oil is a liquid that can be pumped on and off a cargo ship quite easily. They say that if you stand on the bridge of an oil tanker sailing to Japan you can see the smoke from the funnel of the tanker ahead of you and the tanker behind you. Such is the hunger of the Japanese economy for the dark black liquid.

We still don’t know how to bottle electricity and the problems associated with battery storage remain formidable but progress has been made. There have been major electrical cables under the North Sea and the English Channel for many years now. In the southern hemisphere, the Australian government has also built a cable linking Tasmania with the Australian mainland so the idea of using high-energy, direct-current transmission from north Africa to Europe isn’t quite as far-fetched as it sounds. In these circumstances about 12 per cent of the power generated in the Sahara would be lost during transmission. Most authorities believe that the advantages of increased sunlight intensity associated with the north African environment outweigh the problems associated with this power loss.

And if the north African power plant succeeds? What then? Many of the countries involved have a clear memory of their days as European colonies and for some African politicians this is a difficult memory to forget. There are already accusations that north African solar power represents a rebirth of colonialism with European powers attempting to seize resources from Africa for themselves. Some of the optimists for solar power in the Sahara have suggested that most of our power could be generated in the desert but while this kind of political friction still exists, it’s hard to imagine European governments allowing more than 10 per cent of their grid to be supplied from overseas.

Advertisements
Our Duty towards Construction

Our Duty towards Construction

Shreya Chaudhari elaborated on our duty towards construction on in Construction Technology. At a time where it is wondered how fungi can help create a green construction industry, reflecting over our duty towards the construction of buildings cannot do wrong. So read on and find out about the well-founded reasons for doing so.

Construction is the well-known process for men of building houses with some unskilled labours. Thank you for reading the misconcepted sentence. Yes, It’s often seen with an eye of simplicity and frivolous job, which isn’t. We are in much of society’s mindset that a myth is more nurtured than a fact.

Call me old fashioned, but I believe there’s something to be said for doing good, honest work. Construction is sort of the unsung hero of our culture; vital to our infrastructure. Skilled tradesmen build the places we work in, the homes we live and play in, the roads we commute on, and more. Economy’s strength is tightly linked to the construction industry keeping country to move forward. A construction site is moreover different from a person sitting in front of laptop obeying a 9 to 5 cubicle job; it’s an area of daily new challenges to pass on to the next level. It requires a diversity of skills employing everyone deserving to choose as a career.

This is a technical journey of any structure or thoughts right from the foundation to finishing and external works. In building construction, we study how the civil works are carried out in the field after they have been planned by an architect and structurally designed by an engineer. A toddler whenever points his finger towards the swinging tower crane enjoying like the dance of a robot, it’s the duty of the project team to work successfully building block by block over heights.

As we are talking about the heights, so let me take you to the most heighted man-made structure! No required nominees, it’s Burj Khalifa, Dubai (or you can even argue with one of the most famous buildings because 830 metres is really a good number).

Our Duty towards Construction
Burj Khalifa, Dubai (source: internet)

Heard about World One? A structure finding it’s place to be the tallest residential skyscraper, yet under construction of Lodha group, Mumbai.

Our Duty towards Construction
World One, Mumbai (source: internet)

I’ve my stomach full with all these heights as you will mostly get in my next blog; until then let’s see some amazing constructions. The great man-made river project in Libya has listed as the biggest irrigation project in the world. Underneath of the Sahara Desert, it consists of 2800 pipes carrying 6.5 million cubic metres of freshwater every day.

Great man-made River, Libya (source: internet)

The most beautiful building in Jakarta, Regatta Hotel complex was designed by Atelier Enam. The project’s centrepiece is the aerodynamic hotel itself that overlooks the Java sea. Now wondered that struggle to be in top 10 beautiful buildings!

Our Duty towards Construction
Hotel Regatta, Jakarta (source: internet)

But, who knew that continuous endless building of structures would permit to cease for a no while. Because of the nature of his projects, all industries and companies are surged down to a force majeure. The workers are avoiding the work at construction sites due to fear of coronavirus infection. Threatening situations are discovered due to this pandemic endangering future of the construction world.

People are particularly trying to reach out finding alternatives as I mentioned in my previous blog (A virus outside the computer). Also, many cities have adopted a definition of essential construction that allows any work necessary to build, operate, maintain or manufacture essential infrastructure without limitation construction or the constructions required in response to this public health emergency, hospital constructions, etc.

According to the industry body, there are around 20,000 ongoing projects across the country and construction work is being undertaken in around 18,000 of them i.e. involvement of workforce of about 8.5 million in construction work alone! These numbers are breath-taking when health concerns. The scenario implies that the construction work will be slow, pushing costs upward given the interest and debt servicing needed for that extra period. Definitely it will have its own consequences but would be better far than doing nothing.
Hoping the same as everyone to defeat this monster, hiding myself from the fact that I’m bored writing about it  ; )

Sustainable construction projects completed in Qatar during 2019

Sustainable construction projects completed in Qatar during 2019

I love Qatar with Mark Alexander on 6 April 2020 elaborates on more than 50 sustainable construction projects completed in Qatar during 2019. Qatar Construction increased with Permit Issuance up last year.

Once considered a farfetched possibility by skeptics, global warming and climate change are now surfacing as palpable realities of the day. From wildfires in Australia to melting glaciers in Iceland, the year 2020 bid farewell to the hottest ever decade recorded on the planet. Fortunately, though, measures are being taken across all industries to curb our modern world’s carbon footprint, and the case of building and construction sector is no different.

According to a recent UNEP-supported report titled 2019 Global Status Report for Buildings and Construction, construction sector in 2019 continued its notorious position as the largest contributor of greenhouse gas emissions, resulting in 39% of the energy and process-related carbon emissions recorded during the year. The report further states that whilst as many as 136 countries have expressed intentions to work towards sustainable buildings, only a few have elaborated on tangible actions strategized to achieve such plans.

The global building stock is forecasted to grow twofold by 2050 as a direct consequence of increasing urbanization. If left unchecked, GHG emissions resulting from the building industry can rise to 50% of the global carbon emissions in the next three decades. While technological innovations have given way to reduced energy consumption, increasing cooling demand emerging from hot regions have overshadowed a significant positive trajectory. That said, countries across the world are increasingly targeting the urban built environment as a part of their national strategy towards a low-carbon future.

Within the Middle East and North Africa (MENA) region, Qatar houses one of the highest collections of sustainable buildings. Concluding 2019, the country saw completion of more than 50 projects certified under the Global Sustainability Assessment System (GSAS) – MENA’s first performance-based assessment system for green buildings. Based on their overall sustainability credentials, projects registered under GSAS can achieve up to 5 Stars, representing the highest levels of sustainable features in terms of design and build. The award of final rating and certificates follows a comprehensive process whereby auditors from the Gulf Organisation for Research & Development (GORD) analyze several aspects of projects at multiple stages throughout the construction phase.

For the year 2019, here are some green projects successfully completed under GSAS.

Metro Stations:

During 2019, many recipients of outstanding sustainability ratings were linked with Qatar Rail’s Doha Metro project. With Mesheireb Station achieving the highest rating of 5 Stars, another 17 metro stations and 2 stabling yards at different locations within Doha received 4 Stars for their environmentally friendly design and build aspects. Doha Metro is by far the world’s first metro project with accredited sustainable certification specific to rating railway stations. This has been achieved through GSAS’ unique Railways Scheme that is used for rating the sustainability and ecological impacts of new main station buildings, including spaces that serve various functions of a metro station. According to Consolidated Contractors Company, sustainability of the project has been achieved through responsible site development, water saving, energy efficiency, materials selection, cultural and economic value support and innovation in design. Stations awarded GSAS accreditation during 2019 included those located in Msheireb Downtown, Ras Bu Abboud, Al Sadd, Al Sudan, Bin Mahmoud, Qatar University, Hamad International Airport Terminal 1, Al Doha Al Jadeda, Umm Ghuwailina, Ras Bu Fontas, Economic Zone, Al Wakrah, Al Bidda, Corniche, Hamad Hospital, Al Riffa, The White Palace and Education City.

Lusail City Projects:

A number of projects receiving green certifications during 2019 represented Lusail City – Qatar’s first smart city covering 38 square kilometers, that has mandated GSAS to ensure sustainability of all of its buildings. A flagship project of Qatari Diar, Lusail City has been dubbed as the “largest single sustainable development” ever undertaken in the State of Qatar. Use of native flora and water efficient landscaping mechanisms are some ways the city conserves water. Its integrated transport system reduces GHG emissions resulting from private vehicles. The city’s urban connectivity has been achieved through light rail, ample pedestrian walkways, bicycle tracks and park-and-ride facilities at the public transport stations. With a capacity to reduce up to 65 million tons of CO2 per annum, Lusail’s district cooling plant boasts of being one of the largest in the world. Other green credentials benefiting the entire city include a pneumatic waste collection system, sewage treatment plant and an interconnected natural gas network designed to cut down energy consumption.

Within Lusail, Marina Yacht Club Al Khaliji Tower received the highest sustainability rating of 4 Stars during 2019 followed by another 8 commercial, residential and mixed-use developments receiving 4, 3 and 2 stars. Once complete, the city will have the capacity to accommodate 200,000 residents, 170,000 employees and 80,000 visitors without significant impact on the environment.

Health Centers:

Sustainable development is one of the four key pillars of Qatar National Vision 2030, a fact that has provided a natural impetus for public projects to be designed and constructed sustainably. Now, all government projects within Qatar are now mandated to pursue and achieve sustainability under GSAS certification system. To this end, health centers in Al Waab, Al Wajbah, Muaither and Qatar University were successfully completed with 3 Stars sustainability rating during 2019 under the supervision of Public Works Authority ‘Ashghal’. Interestingly, all projects undertaken by Ashghal have been designed and built following sustainability principles – a fact that has been reiterated by Ashghal’s President, Dr. Eng. Saad bin Ahmad Al Muhannadi, who recently emphasized that “Ashghal is implementing GSAS standards in all its public buildings in Qatar, specifically in educational and health buildings.” In the light of these comments, one can safely assume that the upcoming stock of health centers in Qatar will continue to have sustainability at the core of their design and construction.

Hamad Port Project Facilities:

Increasing Doha’s total port capacity, Hamad Port Project started operations in 2016. However, construction has been underway to develop new facilities aimed at enhancing the port’s functional efficiency. The year 2019 witnessed completion of multiple facilities inside the new port with sustainability certification. From accommodation and mosques to civil defense and business center buildings, 19 projects under the umbrella of Hamad Port received sustainability rating between 3 and 2 Stars. Development of the new port has followed comprehensive mechanisms aimed at preserving the environment. For instance, 39,117 mangroves, 14,252 sqm of sea grass and 11,595 hard corals were relocated prior to the construction phase. The relocated flora and fauna are being continuously monitored and have so far proven to be surviving.

Sports Infrastructure:

Taking green sports infrastructure to another level, Al Janoub Stadium received GSAS 4 Stars during 2019, and rightly so. Soon to be a venue for FIFA 2022 World Cup games, the stadium consumes 30 percent less water in terms of international plumbing codes. More than 15% of its permanent building materials are made from recycled content and more than 85% of the waste generated during construction was processed to be reused or recycled, making it one of the most sustainable stadiums worldwide. Apart from Al Janoub, Qatar University’s Sports and Events Complex was another distinguishing project that received 4 Stars under GSAS Design & Build scheme.

mark@iloveqatar.net

Source: Press Release

Oman Prepares for 4th Industrial Revolution

Oman Prepares for 4th Industrial Revolution

Omar Faridi of CROWDFUND INSIDER reports that Oman Prepares for 4th Industrial Revolution, Launches Fintech Innovation Lab with Help of Ministry of Technology and Communications, BankDhofar.
So why is Oman preparing for 4th Industrial Revolution? Let us hear Omar’s point of view.

March 17, 2020

Oman Prepares for 4th Industrial Revolution

Oman’s Ministry of Technology and Communications (MTC) has committed to a memorandum of cooperation (MoC) with BankDhofar at the Sas Center for the 4th Industrial Revolution (4IR), in order to manage a technology innovation lab at the center.

The MoC was reportedly signed by Dr Salim bin Sultan Al Ruzaiqi, CEO at MTC, and Abdul Hakeem Omar Al-Ojaili, CEO at BankDhofar.

The innovation lab has been established to help students and local Fintech startups, as they focus on developing innovative financial technology products and services.

Dr. Salim bin Sultan al Ruzaiqi, stated:

“The Ministry has launched the SAS Center for the 4th Industrial Revolution to keep pace with the current developments in the ICT sector. Signing this MoC with BankDhofar reflects the significant role of the private sector in supporting this dynamic sector and the Omani youth initiatives in entrepreneurship.”

He added that through this cooperation, they aim to create an encouraging environment that can help develop useful Fintech solutions, which could become part of the 4th IR technologies.

He also said the project aims to encourage and support Oman’s private sector organizations to continue to empower the nation’s emerging technology fields.

Abdul Hakeem Omar Al Ojaili remarked:

“The innovative lab at Sas Centre for 4th Industrial Revolution serves our vision of contributing to such projects of national value, and it also contributes to the development of the Fintech field in general.” 

He continued:

“We are in the midst of the 4th Industrial Revolution where the banking sector has to seize the opportunity and take part, supporting the youth and encouraging them to become effective in a field which will positively contribute to the national economic growth in the future.”

MTC and BankDhofar will work cooperatively to establish, host, and manage the innovation lab. They will provide mentorship and training for Omani students, staff, local startups and Fintech firms.

In December 2019, Bank Muscat, the leading financial services provider in the Sultanate, revealed that the Central Bank of Oman had approved the institution’s request to establish a $100 million (appr. OMR38.5 million) nationwide, strategic Fintech investment program.

The investment program is reportedly part of Bank Muscat’s strategic growth initiative.Sponsored Links by DQ Promote

Virtual reality can bring ancient cities back to life

Virtual reality can bring ancient cities back to life

An eye-opener amongst all current development lines in archaeology would be this article dated 27 February 2020 that states that Virtual reality can bring ancient cities back to life and improve conservation.


Virtual reality can bring ancient cities back to life and improve conservation

Tarek Teba, University of Portsmouth

Around 3,300 years ago, the port city of Ugarit was a vibrant urban centre, located strategically on the overland network linking Egypt with Asia Minor and on the route between Persia and India in the east and Greece and Cyprus in the west. The city’s origins date back to 3000BC and the first alphabet and alphabetic writing system are believed to have developed there in the 14th century BC.

Today Ugarit is a Bronze Age archaeological site in northwest Syria, first excavated in 1929. It can tell us a huge amount about the past, but Ugarit is also a place in its own right. The conservation of the site needs to help us understand the site’s history, as well as preserving and restoring what remains. Our work on virtual reality and reconstruction can meet both these goals.

Virtual reality can bring ancient cities back to life
Figure 1: The location of Ugarit and its historic links. Google Map

Although only 30% of Ugarit has been excavated, the discovered areas give clues about the organisation of the city. The buildings include royal palaces, large houses, tombs, sanctuaries, public buildings and temples. Ugarit’s golden age was between the 14th and 12th century BC, and the excavated ruins show that interesting political, social and economic evolution took place in the city.

The royal area shows evidence of a developed political system, with complex defensive architecture and a well-structured palace. Domestic areas reveal important information about the Ugaritic people’s everyday life and their veneration of the dead. However, the structures are in a ruined condition and some are deteriorating, thanks to being exposed for more than 90 years with only minimal maintenance and repair work.

Virtual conservation

A shift toward using virtual technologies as preservation methods to document historic sites and provide educational opportunities has taken place in recent years. This prevents misguided architectural conservation, which can damage a site.

Augmented reality can project reconstructions onto archaeological ruins, such as at the medieval village of Ename in Belgium. Elsewhere, virtual reconstruction has produced 3D textured models, including of the “Sala dello Scrutinio” at the Doges’ Palace in Venice.

Virtual reality can bring ancient cities back to life
Figure 2: A map of the city of Ugarit showing the excavated areas and the sacred route between the Royal Palace and the Temple. Latakia National Museum, Syria

We have used computer-aided design modelling to test out conservation options for Ugarit and to investigate the effects of possible conservation interventions on the ruins. This led to changes in design concepts and materials to better fit the aims of the conservation.

Preserving a sacred route

Excavations have revealed a key sacred route that linked the Royal Palace with the main Temple of Baal and passed through public areas of Ugarit. Researchers believe that the king followed this sacred path to practice cult sacrifices at the temple.

The route contains important tangible elements, such as the remains of the palace, houses, and the temple, for example. But the conservation strategy also intends to reconstruct the intangible aspects of the route – the monumental fortifications, the scale of the temple, and the experience of walking the sacred path, all of which cannot be easily grasped from the remaining ruins.

Virtual reality can bring ancient cities back to life
Figure 3: Point A of the Sacred Route. The Author

Virtual reconstruction is an effective tool to assess these proposals and judge their ability to protect the ruins, as well as revealing intangible aspects, such as the atmosphere of a street, which are lost to time. We have developed virtual tours which create an opportunity for screen displays to be installed on the site before the actual proposal is implemented.

Virtual reality can bring ancient cities back to life
Figure 10: Virtual reconstruction of interventions proposed for Point C of the sacred route – the Temple of Baal. The author, Author provided

These virtual tours include an area of the site that historically featured a plaza and tavern. Here the conservation approach includes the creation of a social and entertaining hub. This will allow the urban environment of the plaza and the dim and cosy interior of the tavern to be restored.

The tours provide reliable evidence for the second stage of the conservation proposal, the design stage and community consultation. However, the political situation in Syria has put the consultation process on hold.

This political situation also means that it is not possible to visit Ugarit at the moment – a position shared by hundreds of archaeological sites around the world. So the virtual reconstructions serve another purpose: they allow those interested a glimpse of this fascinating city and provide an opportunity to raise awareness of the site’s cultural importance with an international audience.

Tarek Teba, Senior Lecturer, School of Architecture, University of Portsmouth

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The Conversation

Raising crops in PV facades of buildings

Raising crops in PV facades of buildings

An international research group has analyzed the visual impact of PV facades on buildings which include crop cultivation. Architects, PV specialists and farmers were surveyed and the results showed broad acceptance of such projects. The ‘vertical farming’ survey generated suggestions for the design of productive facades. So here is Raising crops in PV facades of buildings by Emiliano Bellini.


February 19, 2020

An international research team including scientists from Cuba’s Technological University of Havana and the National University of Singapore has investigated the potential of integrating PV facades with ‘vertical farming’ on buildings in densely-populated cities.

According to findings presented in the study Architectural quality of the productive façades integrating photovoltaic and vertical farming systems: Survey among experts in Singapore, published in Frontiers of Architectural Research, there is broad acceptance for projects combining crop cultivation and solar power generation – which the researchers defined as “productive facades (PF)” – despite concerns over architectural integration.

Web survey

The researchers conducted anonymous 10-minute, multiple-choice web surveys in English with 15 questions. The group also provided images of four variants of productive facade, with respondents asked to rate their architectural quality on a scale of one to five.

The questions addressed topics including the visual impact of PV modules and crops, preferences about the arrangement of PV modules and ease of operation for owners and workers. Around 80% of the 97 respondents were architects with the remainder engineers, PV specialists, productive facade experts, horticulturalists, solar facade professionals, consultants and other professionals.

Architectural concerns

The results indicated architects and designers gave low ratings to all four of the designs presented and rated the design of PV installation poor. However, respondents with experience in horticulture, farming and PV facades showed stronger acceptance of building-integrated productive facades. “All groups of experts agree that PFs have the most positive effect on the exterior facade design and have accordingly graded them with higher marks than the designs without PV and VF [vertical farming] systems,” the paper noted.

Concerns were expressed by almost all respondents about the logistics of crop cultivation and irrigation near electronic devices such as the vertical solar modules.

“Several comments recommended exploring more creative designs,” the researchers added.

The lowest rating – 2.84 – was given to a productive facade with only PV modules visible from the inside. The highest mark – 3.9 – was scored by the image in which only plants were visible.

Tips for developers

The study also generated recommendations for the improvement of productive facade prototypes. “It should be noted that the selection of elements for practical application cannot be made based on a single isolated PF element – the entire building should be considered, especially the aesthetic elements of the building envelope, such as composition, proportion, rhythm, transparency, scale, colors and materials,” the researchers stated.

The study’s authors recommended the installation of the PV systems on north and south-facing facades, with ceiling level a preferable location.

Tilt angles of less than 20 degrees were suggested as a better aesthetic solution which would also avoid reflection onto neighboring buildings. “However, a well-designed integration of the PV modules with the planter of the above storey provides additional advantages – it improves the quality of indoor daylight and obstructs the view from inside to a lesser degree,” the study stated.

The researchers added copper indium gallium selenide (CIGS) panels were preferred to crystalline silicon modules, due to their more homogeneous structure.

Emiliano Bellini

Emiliano joined pv magazine in March 2017. He has been reporting on solar and renewable energy since 2009.

emiliano.bellini@pv-magazine.com

More articles from Emiliano Bellini

Read more on:

Automation ‘to take over half of all jobs in 15 years’

Automation ‘to take over half of all jobs in 15 years’

The robots are coming! started The Guardian in its 2017 edition before informing that regular reports warn us that an automation apocalypse is nigh.  Here is Automation ‘to take over half of all jobs in 15 years’ that again alerts us on everything but the positive aspects if any, of such technological advancements.


Approximately half of all jobs will be materially impacted by automation in the next 15-20 years, said professional services firm Accenture in a new report.

Meanwhile, 79 per cent of executives agree that work is shifting from roles to projects—challenging both the function and makeup of the workforce as we know it, said Tanushree Guha, managing director of Applied Intelligence and global lead for the Workforce Analytics practice at Accenture in the report titled “OCED Employment Outlook 2019: The Future of Work”.

As more and more employees look for different opportunities, many are not choosing permanent jobs. In 2018 alone, 56.7 million Americans freelanced, and it is predicted that by 2027, the majority of America’s workers will be freelance. Those choosing part-time work or even working for multiple employers at one time will need to be factored into evolving workforce models, says Guha.

“Advances in digital and automation have allowed organizations to gain efficiency and increase productivity. But adopting these technologies means that organizations must plan for their workforce—especially those at risk of being made redundant,” the report said.

As many as 40 percent of companies are already reporting that talent shortages are impacting their ability to adapt and innovate and this highlights the need for organizations to upskill, reskill and cross-skill existing workers, it added.

A new approach to workforce management

Strategic workforce planning (SWFP) helps organizations strike the right balance between external contractors and internal workforce, as well as the right blend of human and machine effort to drive the business forward.

By providing a holistic perspective of the current workforce, and existing as well as future gaps, workforce planning can help organizations assess forthcoming risks and identify quick wins to yield potential savings. This enables organizations to strategize their recruitment and reskilling plans well in advance, as well as ascertain the most advantageous size and workforce mix of the organization both in the short and long term, the article said.

For example, using HR transformation analytics, organizations are turning recruitment from what was traditionally often a process based on “gut-feel,” to one informed and backed by advanced data insights. This transformation enables businesses to find the right people at the right time with the most relevant skills from a larger pool of applicants, whilst saving on time and money.

According to Guha, SWFP helps companies to be in a future-ready state, by enabling them to:

•    Have a good hold of the current workforce scenario
•    Be well informed of possible future workforce gaps, facilitating them to strategize gap fulfilment and avoid the probable revenue losses due to those gaps
•    Devise a comprehensive action plan on efficiently utilizing the various workforce types to drive maximum productivity
•    Be well aware of the overtime changes in workforce dynamics and reasons for those changes
•    Design and implement optimal reskilling strategies in line with the changing requirements, at the same time as providing optimal career pathways to their workforce. – TradeArabia News Service

Buildings kill millions of birds. Here’s how to reduce the toll

Buildings kill millions of birds. Here’s how to reduce the toll

In Reach for the Sky—Wood Frame Building Will Be 35 Stories, there was no question about any other matter such as the possibility of these buildings killing birds and in this case, how to reduce this eventuality. To dutifully fill that gap, here is Norman Day, of Swinburne University of Technology who informs that Buildings kill millions of birds. Here’s how to reduce the toll.

Buildings kill millions of birds. Here’s how to reduce the toll


Buildings kill millions of birds. Here's how to reduce the tol
These birds were killed by flying into a set of surveyed buildings in Washington DC in 2013. USGS Bee Inventory and Monitoring Lab/Flickr

As high-rise cities grow upwards and outwards, increasing numbers of birds die by crashing into glass buildings each year. And of course, many others break beaks, wings and legs or suffer other physical harm. But we can help eradicate the danger by good design.

Most research into building-related bird deaths has been done in the United States and Canada, where cities such as Toronto and New York City are located on bird migration paths. In New York City alone, the death toll from flying into buildings is about 200,000 birds a year.

Across the US and Canada, bird populations have shrunk by about 3 billion since 1970. The causes include loss of habitat and urbanisation, pesticides and the effects of global warming, which reduces food sources.

An estimated 365 million to 1 billion birds die each year from “unnatural” causes like building collisions in the US. The greatest bird killer in the US remains the estimated 60-100 million free-range cats that kill up to 4 billion birds a year. Australia is thought to have up to 6 million feral cats.


Read more: For whom the bell tolls: cats kill more than a million Australian birds every day


But rampant global urbanisation is putting the reliance on glass buildings front-of-stage as an “unnatural” cause of bird deaths, and the problem is growing exponentially.

In the line of flight

Most birds fly at around 30-50km/h, with falcons capable of up to 200km/h. When migrating, birds generally spend five to six hours flying at a height of 150 metres, sometimes much higher.

And that’s where the problems start with high-rise buildings. Most of them are much taller than the height at which birds fly. In Melbourne, for example, Australia 108 is 316 metres, Eureka 300 metres, Aurora 270 metres and Rialto 251 metres. The list is growing as the city expands vertically.

The paradigm of high-rise gothams, New York City, has hundreds of skyscrapers, most with fully glass, reflective walls. One World Trade is 541 metres high, the 1931 Empire State is 381 metres (although not all glass) and even the city’s 100th-highest building, 712 Fifth Avenue, is 198 metres.

To add to the problems of this forest of glass the city requires buildings to provide rooftop green places. These attract roosting birds, which then launch off inside the canyons of reflective glass walls – often mistaking these for open sky or trees reflected from behind.

Buildings kill millions of birds. Here's how to reduce the tol
Reflections of trees and sky lure birds into flying straight into buildings. Frank L Junior/Shutterstock

A problem of lighting and reflections

Most cities today contain predominantly glass buildings – about 60% of the external wall surface. These buildings do not rely on visible frames, as in the past, and have very limited or no openable windows (for human safety reasons). They are fully air-conditioned, of course.


Read more: Glass skyscrapers: a great environmental folly that could have been avoided


Birds cannot recognise daylight reflections and glass does not appear to them to be solid. If it is clear they see it as the image beyond the glass. They can also be caught in building cul-de-sac courtyards – open spaces with closed ends are traps.

At night, the problem is light from buildings, which may disorientate birds. Birds are drawn to lights at night. Glass walls then simply act as targets.

Some species send out flight calls that may lure other birds to their death.

Buildings kill millions of birds. Here's how to reduce the toll
White-throated Sparrows collected in a University of Michigan-led study of birds killed by flying into buildings lit up at night in Chicago and Cleveland. Roger Hart, University of Michigan/Futurity, CC BY

Read more: Want to save millions of migratory birds? Turn off your outdoor lights in spring and fall


We can make buildings safer for birds

Architectural elements like awnings, screens, grilles, shutters and verandas deter birds from hitting buildings. Opaque glass also provides a warning.

Birds see ultraviolet light, which humans cannot. Some manufacturers are now developing glass with patterns using a mixed UV wavelength range that alerts birds but has no effect on human sight.

New York City recently passed a bird-friendly law requiring all new buildings and building alterations (at least under 23 metres tall, where most fly) be designed so birds can recognise glass. Windows must be “fritted” using applied labels, dots, stripes and so on.

The search is on for various other ways of warning birds of the dangers of glass walls and windows.

Combinations of methods are being used to scare or warn away birds from flying into glass walls. These range from dummy hawks (a natural enemy) and actual falcons and hawks, which scare birds, to balloons (like those used during the London Blitz in the second world war), scary noises and gas cannons … even other dead birds.

Researchers are using lasers to produce light ray disturbance in cities especially at night and on dark days.

Noise can be effective, although birds do acclimatise if the noises are produced full-time. However, noise used as a “sonic net” can effectively drown out bird chatter and that interference forces them to move on looking for quietness. The technology has been used at airports, for example.

A zen curtain developed in Brisbane has worked at the University of Queensland. This approach uses an open curtain of ropes strung on the side of buildings. These flutter in the breeze, making patterns and shadows on glass, which birds don’t like.

These zen curtains can also be used to make windows on a house safer for birds. However, such a device would take some doing for the huge structures of a metropolis.

More common, and best adopted at the design phase of a building, is to mark window glass so birds can see it. Just as we etch images on glass doors to alert people, we can apply a label or decal to a window as a warning to birds. Even using interior blinds semi-open will deter birds.

Birds make cities friendlier as part of the shared environment. We have a responsibility to provide safe flying and security from the effects of human habitation and construction, and we know how to achieve that.


This article has been updated to correct the figure for the estimated number of birds killed by the cats in the US to “up to 4 billion”, not 4 million.

Norman Day, Lecturer in Architecture, Practice and Design, Swinburne University of Technology

This article is republished from The Conversation under a Creative Commons license.

Siemens transforms buildings from passive to adaptive

Siemens transforms buildings from passive to adaptive

In a Press Release on 6 February 2020, Siemens transforms buildings from passive to adaptive as elaborated on below.


At this year’s Light+Building trade fair, Siemens will showcase its vision for transforming today’s passive buildings into learning and adaptive environments that intelligently interact with people. The company’s focus at this year’s show is “Building the future today”, outlining the innovations that will make this possible. These include cloud-based technologies, digital planning, occupant-centric building automation and services. New solutions for smart electrical infrastructure that seamlessly connects to the Internet of Things (IoT) are also at the core of this transformation. 

Siemens transforms buildings from passive to adaptive

„Building the future today”: Siemens at Light+Building 2020 in hall 11, booth B56“Around 99 percent of today’s buildings are not smart. Digitalization has the power to transform buildings from silent and passive structures into living organisms that interact, learn from and adapt to the changing needs of occupants. This is a significant leap in the evolution of buildings where our technology plays a vital role,” said Cedrik Neike, Member of the Managing Board of Siemens AG and Chief Executive Officer of Siemens Smart Infrastructure. “This transformation is already becoming a reality. We expect to see the first entirely self-adaptive buildings in three to five years from now.”

Digital solutions for the entire building lifecycle

Globalization, urbanization, climate change, and demographics are changing the way people live and work. At the same time, digitalization is ubiquitous. With some 10 billion building devices already connected to the IoT, buildings are ready to leverage the potential of digitalization. People spend an estimated 90 percent of their lives indoors, so ensuring buildings meet the broad range of individuals’ needs is crucial. On one hand, smart buildings actively contribute to occupants’ enhanced productivity, wellbeing and comfort. For operators and owners, they help them collect and analyze data to create actionable insights, boosting buildings’ performance and therefore revenue.Siemens will showcase the smart buildings suite of IoT enabled devices, applications and services. At the core of the suite is the “Building Twin” application, which will be on display at the booth. It provides a fully digital representation of a physical building, merging static as well as dynamic data from multiple sources into a 3D virtual model. With real-time understanding of how a building is performing, operators can immediately make adjustments to boost efficiency as well as extract data to improve the design of future buildings. One of the new IoT-enabled applications is “Building Operator”, which allows remote monitoring, operation and maintenance of buildings. Available as Software as a Service (SaaS), it provides real-time building data as the basis for predictive and corrective maintenance.

Smart electrical infrastructure

Given that buildings account for more than 40 percent of electricity consumption in cities, building efficiency is crucial in the battle towards decarbonization. Electrical infrastructure lays the foundation for safe, reliable and efficient building operations, while delivering essential data for a holistic, cloud-based building management. This is made possible by communication-capable low-voltage products, power distribution boards and busbar trunking systems that enable the measurement and wireless transmission of energy and status data. To illustrate this, Siemens will exhibit a unique end-to-end solution for cloud-based power monitoring in buildings. Electrical installations can now be supplemented with digital metering without additional space requirements or wiring outlay. This makes it easy for electrical installers to start using digitalization to their benefit. With “Powermanager”, a power monitoring software, now fully integrated into the Desigo CC building management platform, all building and energy data can be managed, monitored and analyzed from one single platform.Siemens will also display its electromobility ecosystem, including battery storage and charging systems for residential buildings. In a parallel show, “Intersec Building 2020”, in hall 9.1, booth B50, the company will exhibit integrated and networked systems for safety and fire protection.  

For further information on Siemens Smart Infrastructure, please see
www.siemens.com/smart-infrastructure

For further information about Siemens at Light+Building 2020, please see
www.siemens.com/press/lightbuilding-2020

Nehmeh organises Mega Industrial Expo 2020

Nehmeh organises Mega Industrial Expo 2020

As reported by The Peninsula of Qatar of 11 February 2020, Nehmeh organises Mega Industrial Expo 2020.

Qatar-based Industrial Solutions leader ‘Nehmeh’ has organised the annual Mega Industrial Expo 2020 showcasing a range of the world’s leading brands in construction solutions,

Visitors during the annual Mega Industrial Expo 2020.

The two-day event was held on February 4 and 5 at a five-star hotel in Doha where Nehmeh showcased power tools, ventilation systems, light construction tools and machinery with a focus on concrete machinery along with demonstrations to let guests have a first-hand product experience of the machines and its applications.

An important part of the event was the launch of the Qatar’s first locally manufactured ‘Roof Top Package Unit’ by Nehmeh Air Conditioners and introduction of Belgium based ‘Beton Trowel’ brand renowned for Concrete & Compaction Equipment.

The event also featured key note address by experts from Beton Trowel, Nehmeh Air Conditioners and Makita over the two days.
‘Nehmeh App’ the region’s first industrial solutions mobile app was highlighted to guests at the expo. Nehmeh, one of the leading industrial solutions providers in the GCC, represents world class brands which are leaders in their respective categories.

For over 65 years, tens of thousands of people depend on reliable industrial performance solutions by Nehmeh. This mega event succeeded in attracting visitors including retail partners, suppliers, end-users and others related to the construction industry.

Visitors also included managers from Qatar looking for solutions to improve their efficiency and productivity on sites. Brands participating at the expo were Makita, Nehmeh Air Conditioners, Stampa, SDMO, Beton Trowel, Sofy, Portacool, Koshin, Awelco, Dr. Schulze among many more. Demonstrations were held on specially prepared areas showcasing tools, equipment and machinery. Expert professionals from Singapore, Germany and Belgium presented to the audience new introductions and technologies along with an informative Q & A session.

“Nehmeh range of Industrial Solutions cover major solutions required for the Qatari construction market. This concept event has been developed keeping in mind the requirements of our customers and I am glad to say that the event has been well received by the guests over the years,” said Emil A. Nehme, Chief Executive Officer at Nehmeh.

“With the support of our partners, we have the ability to cover major construction solutions as required here in Qatar. Witnessing the popularity of such an event, we are inclined to hold more such regular events as part of our calendar of activities,” he added.

‘The Nehmeh Corporate Catalogue 2020’ was launched during the event. Awards bestowed to various partners as tribute to their efforts and achievements. In addition, four lucky visitors also walked away with reward trips, gold coins and stay vouchers.

A new solar desalination system to address water scarcity

A new solar desalination system to address water scarcity

The GivePower non-profit founded by Tesla subsidiary SolarCity is supplying solar-powered desalination systems to some of the world’s neediest communities, backed by Tesla’s Powerwall battery technology. It is elaborated on in A new solar desalination system to address water scarcity by JEAN HAGGERTY.

FEBRUARY 6, 2020 

A new solar desalination system to address water scarcity

One of GivePower’s desalination projects. Image: GivePower

From pv magazine USA.

GivePower is launching containerized, solar-powered water desalination and purification plants in Mombasa, Kenya and La Gonave, Haiti this quarter. Like GivePower’s debut solar-powered microgrid desalination plant, which went live in Kiunga, Kenya in 2018, these new projects will operate with Tesla’s powerwall battery storage technology.

At launch, both of the nonprofit’s new solar water farm projects will produce a maximum of 75,000 liters of water a day by coupling a 50-kW solar system with 120 kW-hrs of Tesla batteries; together this solar plus battery system will power two low-wattage, reverse osmosis desalination pumps that run simultaneously to ensure continuous operation.

When developing solar-powered desalination projects, pinning down the point at which the technology and the operating model make economic sense is key because the one of the biggest challenges with solar desalination is the amount of energy that it takes to desalinate sea water. Often, this outsized energy need means that a plant requires a larger solar array, which increases the cost of the project.

“We need to see that [these philanthropic] projects are economically viable – that these projects can continue to operate without ongoing funding from donors to keep the systems operational,” said Kyle Stephan, GivePower’s vice president of operations. In addition to building solar water farms, GivePower trains local technicians to operate the plants.

GivePower’s solar water farm systems cost just over $500,000, and they have a 20-year expected lifespan.

Commercial applications for GivePower’s solar water farm technology are not in the pipeline currently, according to Hayes Barnard, CEO of GivePower.

When it comes to developing commercial off-grid, solar-powered desalination systems for water-stressed communities, industry officials see solar microgrid players as particularly well placed to offer solutions.

Drought, saltwater intrusion and climate change are intensifying the need for solutions that use renewable energy to address water scarcity. Simultaneously, falling PV prices and energy storage innovations are making solar-powered desalination solutions more appealing.

So far, all of GivePower’s solar water farms are coastal well-based desalination plants. This is because 98% of the world’s water is in the ocean, and 73% of the world’s population live in coastal areas, where well water is susceptible to becoming brackish, Barnard noted. Additionally, off-coast solar desalination plants’ intake processes are expensive, and coastal well-based solar water farms do not stress underground aquifers.

For its project on La Gonave, which is off the coast of Port-au-Prince, GivePower is applying international building code seismic requirements for its solar water farm’s concrete foundation, and it is building a solar canopy that is capable of withstanding a category-four hurricane.

Initially, the nonprofit focused on providing solar-powered lighting to schools without electricity in the hope that this would open up educational opportunities for girls in developing countries. But quickly it became clear that helping communities achieve water security was key to addressing this issue because often girls were often missing school because their days were spent fetching water, according to Barnard, a GivePower co-founder. GivePower became an independent organization in 2016.

Last week GivePower’s solar-powered desalination technology received the UAE’s Global Water Impact Award for innovative small projects.

More articles from Jean Haggerty

E-mail: jean.haggerty@pv-magazine.com

Related topics:

Reach for the Sky—Wood Frame Building Will Be 35 Stories

Reach for the Sky—Wood Frame Building Will Be 35 Stories

Sidewalk Labs prototype would be the world’s tallest wood-frame building. That is good to know but Reach for the Sky—Wood Frame Building Will Be 35 Stories by Roopinder Tara posted on January 28, 2020, could seriously be envisaged if the world were to be limited to the northern as well as to the Equatorial zones where forestry abounds. Transporting however wooden building materials from and/or to any other area of the world would probably cancel any significant environmental benefits.


Look closely—it’s made of wood. Exterior rendering of office and residential levels of Proto-Model X, Sidewalk Labs’ model of a timber frame destined for the Toronto waterfront. (Image courtesy of Michael Green Architecture and Gensler.)
Look closely—it’s made of wood. Exterior rendering of office and residential levels of Proto-Model X, Sidewalk Labs’ model of a timber frame destined for the Toronto waterfront. (Image courtesy of Michael Green Architecture and Gensler.)

Given that wood is flammable and biodegradable, it may never have been an ideal building material. We have steel for that. However, in many parts of the world, wood is available in abundance, so it is pressed into service for our buildings. Wood framing is common in North America for residential buildings but less so for commercial buildings. Wood framing has largely been unheard for use in high rises—until today, when plans of a 35-story wood frame skyscraper, part of Sidewalk Labs development project in Toronto, popped into my inbox.

No building this tall has ever been built with a wood frame. It’s not even close. The current tallest wood-frame building is Norway’s 85.4m-tall Mjøstårnet. The second tallest is the 53m-tall Brock Commons Tallwood House in Vancouver. Both buildings are 18 stories.

Sidewalk Labs has a digital model, a proof of concept it calls the PMX Tower (Proto-Model X). There’s a lot to be worked out when making a wooden building this tall.

Engineering Wood

Looks like the real thing because it mostly is. Mass wood, an engineered structural material, can pass for normal wood—at a distance. (Image courtesy of HGA.)
Looks like the real thing because it mostly is. Mass wood, an engineered structural material, can pass for normal wood—at a distance. (Image courtesy of HGA.)

The PMX plans do not call for using plain, ordinary wood, but “mass wood,” or a wood-mostly material that when glued together is called “glulam” and is used for ultra-long beams and columns. It is called nail laminated timber (NLT), and the plywood-like cross-laminated timber (CLT), which is used for floor and roof decks as well as bearing walls. Mass wood can be made fire resistant with the addition of chemical fire retardants, though this certainly makes the material less green. Mass wood’s manufacturers claim that the carbon emissions produced from making it are far less than the emissions created in making of steel or concrete—though cutting down trees is hardly green. Mass wood looks better than steel or concrete. We cannot argue with that. Plans for PMX call for a wooden external skeleton. (Image  courtesy of medium.com.) Plans for PMX call for a wooden external skeleton. (Image courtesy of medium.com.)

With a much lower strength-to-weight ratio than steel, wood of any type poses special challenges. But with a Sidewalk Labs team dead set on sustainability, a steel frame and concrete curtain walls were a nonstarter. Still, duplicating the same type of frame used in steel and concrete construction with wood would have resulted in ridiculously massive structural elements. A “timber core” design would have walls 5-feet thick. Not only would walls this thick require too many trees, they would also be difficult to manufacture and ship. In addition, they would take up too much floor space. PMX is going with a design that uses a wooden “exoskeleton” consisting of diagonal bracing and vertical columns on the outside of the building that support a 10-inch-thick “lean wood core.”

The BIM was done with Autodesk Revit and is hosted on BIM 360, a cloud-based construction management application.

A Counterintuitive Counterweight

A concrete and steel tower would be 2.5 times as heavy as a wooden skyscraper. But whereas light weight is an asset in aircraft and rockets that seek to escape gravity, it can be a liability in buildings that need to stay put. Preliminary analysis showed the 35-story wood frame construction had as much deflection in the wind as a 40- to 50-story building constructed with a steel frame.

With the addition of a tuned mass damper, the PMX tower model stabilizes quicker. A gust of wind would make the towers bend to one side, then oscillate. Without losses, the tower would oscillate forever, but internal dampening would cause the structure to stop eventually. A tuned mass dampener would add more losses and make the tower stop swaying sooner. Note that in the model shown the dampener would only reduce swaying from right and left, but not back and forth. (Image courtesy of Gensler, Aspect.)

The PMX team found that it had to allow a lot of steel into the design—in the form of a 70-ton steel weight, part of a system that is designed to dampen vibration.

While it may seem counterintuitive—perhaps even dangerous—to have massive weight on top of a building, that is exactly what civil engineers may order for a tall building that is swaying too much or is expected to do so. Tall buildings can have deflections of several feet on their top floors—unsettling and even sickening their occupants. A tuned mass dampener (TMD) system, can be designed in or retrofitted. A TMD with a precisely calculated amount of mass made of concrete, steel, lead or other dense material stays still due to its own inertia when a tall building initially bends— as a result of the ground shaking or a gust of wind. Dampeners attached to the mass absorb the energy and act to limit the number of oscillations.

Chicken Little would not approve. An 18-ft diameter, 660-metric ton steel sphere, which hangs like a pendulum and is visible between the 88th and 92nd floors of Taipei 101 in Taiwan, is a tuned mass damper (TMD) that reduces the swaying of tall buildings. (Image courtesy of Pinterest.)
Chicken Little would not approve. An 18-ft diameter, 660-metric ton steel sphere, which hangs like a pendulum and is visible between the 88th and 92nd floors of Taipei 101 in Taiwan, is a tuned mass damper (TMD) that reduces the swaying of tall buildings. (Image courtesy of Pinterest.)

TMD systems have been around for some time, but the increase in super tall and very thin tall buildings has made them even more sought after. Shanghai, New York and Dubai have several buildings with TMDs. Taiwan’s Taipei 101 tower uses a system that makes its TMD, with a suspended golden ball, a visible design feature.

The Canadian National Tower, at one time the tallest structure in North America at 102m, also in Toronto’s downtown, has two doughnut-shaped steel rings, one at 488m and the other at 503m—each weighing 9 metric tons—that serve as TMDs. They are tuned to the 2nd and 4th mode shape of the tower, while the 1st and 3rd mode are controlled by the prestressed concrete and don’t require additional damping.

Boston’s John Hancock Tower had two 30-ton sliding dampers installed retroactively that were designed to reduce the building’s sway by 40 percent to 50 percent.

TMDs can take several forms, including sliding, rolling or swinging weights.

Not Your Parents Prefab

Mechanical, electrical and plumbing equipment is embedded in a floor panel off-site in a factory. (Image courtesy of Integral.)
Mechanical, electrical and plumbing equipment is embedded in a floor panel off-site in a factory. (Image courtesy of Integral.)

As much as possible, the PMX designer sought to make the building off-site in parts, and then assemble the parts on-site. This is the long sought-after advantage manufacturing has enjoyed, while construction has lagged behind. PMX is making staircases, floor panels, walls, and kitchen and bathroom “pods” standard and assembled in assembly lines, transporting them to the waterfront site on trucks, and then snapping them together … like Legos, according to this article. These “cassettes,” as the sub-assemblies are called, will be made in 25 steps, with each step estimated to take 25 minutes. It is assembly line techniques at work, rather than the painstaking, laborious, material wasting current practice of laying floors, pouring concrete, joining gigantic steel members, and so on, that is the common conventional construction trade practice.

In addition to busting out of age-old construction practices, the PMX also hopes to bust out of the lowly status that prefab construction can’t seem to shake, like a screw-top wine. The plan’s exoskeleton can be draped in any manner of dress and color—a far cry from the welcome to middle-class, prefab homes in cookie cutter neighborhoods that gave prefab a low-class status.

Sidewalk Toronto

Sidewalk Labs has a $1.3 billion project to develop Quayside, a 12-acre area in Toronto on the banks of Lake Ontario. Sidewalk Labs, part of Alphabet Inc., which also owns Google, was formed to create communities “from the Internet up.” When complete, Sidewalk Toronto would potentially bring 44,000 jobs, many of them tech jobs, to Toronto’s downtown. It was to be a test bed for technology close to city scale, including roads especially designed for autonomous vehicles. But the proposal may have represented too much technology for Toronto’s residents. Sidewalk Labs plans to pool and make public “urban data” gathered from those who were in Sidewalk Toronto. The city will be voting on whether to move forward with the Sidewalk Labs proposal.

%d bloggers like this: