construction industry Archives - Zureli

Search for any green Service

Find green products from around the world in one place

Window cleaning

Singapore Safety Glass

4 Stepping Stones to Sustainability for New Construction Firms

Posted on March 15, 2024 by dishanth

4 Stepping Stones to Sustainability for New Construction Firms

The construction industry has a well-deserved reputation for being an environmental polluter. It has gotten away with ungreen practices because the other sectors are just as dirty, if not more. However, climate change has made the world less tolerant of environmentally unsound organizations. Governments have joined the sustainability movement, so the writing is on the wall for maladaptive enterprises.

Many firms are slow to adopt greener practices, but the influx of startups can accelerate the sector’s sustainability transformation. New design-build firms, general contracting businesses, and subcontractors are better positioned to embrace eco-friendly initiatives.

The corporate culture is still a blank canvas, so start fresh with these four tips.

Go Digital

Technological adoption and sustainability go hand in hand. Outdated methods and crude tools limit your ability to overcome your blind spots and find opportunities to operate more sustainably. Investing in digital technologies is necessary to address your pain points and streamline your processes.

Which innovations should you prioritize? There are numerous excellent candidates:

Mobile devices and messaging tools can harness cloud computing’s potential to promote remote resource access and foster interconnectedness. The interplay between these technologies will break down the usual communication barriers, making it easy to keep everybody on the same page.
Computer-aided design, building information modeling, and construction management programs streamline processes. They have unique functions but digitize data so you can review information more granularly. Analytics programs can reveal insights to solve problems that harm the environment, like surplus inventory and rework.
LiDAR and camera-equipped drones, wearable Internet of Things devices, and telematics systems can collect data on almost anything. They can help you precisely and accurately scan the landscape to minimize disturbance on existing ecosystems, quantify worker performance to identify and correct wasteful habits and keep tabs on equipment usage.
Bots automate tedious tasks, allowing you to conduct construction work more efficiently. Robotic arm 3D printers and bricklayers can help you complete projects faster and decrease material waste.

Construction has been slow to innovate primarily due to employee hesitance. Feeling intimidated by innovative solutions and receiving inadequate technical support are some of the usual baggage crews carry. Budget for training and continuous learning, as technologically savvy workers feel comfortable with innovations and can maximize their tools to run your business more sustainably.

Be Circular

Circularity promotes using renewable, reclaimed or recycled materials, reusing or repurposing items, recovering salvageable materials, and designing structures with easily recoverable components. Such practices aim to leave the remaining virgin resources untouched because logging, mining and quarrying have considerable environmental consequences. These extraction methods destroy natural habitats, displace wildlife, eradicate biodiversity, pollute soil, water and air, and reduce natural carbon sinks.

Considering the planet’s finite resources, the construction industry has to switch from the linear to the circular model sooner rather than later. Otherwise, the sector will face crippling supply chain disruptions, which can result in project delays and loss of profits. How do you join the circular economy?

Buy reclaimed, recycled and repurposed construction supplies: Try doing so whenever you can to help conserve virgin resources.
Choose vendors carefully: Circular suppliers engaging in unethical practices practice greenwashing, not sustainability. Exercise due diligence to ensure your supply chain partners are as green as they claim to be to avoid enriching environmentally damaging businesses.
Select used equipment over new products: Purchasing pre-owned tools, machines and vehicles is sustainable because they’re already around. Ordering brand-new assets incentivizes manufacturers to build more products, potentially using newly extracted raw materials. Plus, pre-owned models save you money because used items cost less, less downtime is necessary for training and replacement parts are usually cheaper.
Put a premium on prefabrication: Prefab construction minimizes waste since it’s easier to control material usage when building components off-site in a factory-controlled environment. More importantly, construction modules lend themselves to deconstruction, simplifying dismantling and material recovery for reuse or resale.

Emit Less

Decarbonize your operations at every turn. Switching from diesel to electric is one of the best ways to do so. Powering your assets with nothing but electricity eliminates air and noise pollution on-site.

Running on electricity doesn’t automatically translate to fewer greenhouse gas emissions. In 2023, fossil fuels produced 60% of the electricity generated in the United States. The nation’s power mix will be cleaner once green hydrogen becomes ubiquitous, so operating electric construction assets will be even more eco-friendly in the future.

If upgrading to electric equipment doesn’t make sense for you, adopting renewable diesel is the next best thing. This alternative fuel is chemically identical to fossil-derived diesel, so you can use it on your existing assets without modifying anything. Renewable diesel releases fewer climate change gasses because it burns cleaner.

Furthermore, localize your supply chain. Ships are responsible for 3% of all greenhouse gasses linked to human activities globally. Ordering materials from overseas will increase your construction firm’s carbon footprint, but transporting domestically sourced materials involves fewer emissions. It’s also logically simple because they cover less ground and avoid Customs and Border Protection. As a bonus, you enjoy shorter lead times.

Make it a mission to have a lean mindset. A lean construction philosophy aims to cut waste at every chance, minimizing idle time and redundant processes that drive up greenhouse gas emissions.

Look Ahead

Sustainability isn’t an objective — it’s a purpose. It’s a never-ending pursuit, so always seek new ways to run your construction firm in an environmentally friendly way.

Lack of knowledge about emerging technologies is among the limiting factors in innovating. Curiosity is the antidote to ignorance, so keep up with the hottest trends in eco-building. Transparent wood, superabsorbent hydrogel, luminescent cement, 3D-printed soil structures, biodegradable polyurethane foam and plasma rock are some of the most promising innovations.

Most promising eco-friendly construction solutions take a lot of development before becoming ready for sale — and only a few ultimately gain mainstream acceptance. Although many ingenious ideas don’t pan out, be ahead of the curve. Use them to inspire regenerative and climate-resilient building designs that positively impact the environment for decades.

Take Small Steps Toward Sustainability

These four strategies only scratch the surface of what you do to be a force for good in the sector’s sustainability transformation. Strive to be more eco-friendly as you grow and you’ll establish a solid reputation as a green construction business.

Source Happy Eco News

How the World’s Whitest Paint Can Reduce Energy Use

Posted on March 7, 2024 by dishanth

Scientists have long understood the climate and energy efficiency benefits of reflective white paints. Now, engineers at Purdue University have created the world’s whitest paint that reflects more than 98% of sunlight, leaving all other paints appearing grey by comparison. As demand for sustainable solutions grows globally, this innovation promises greener buildings and cities by passively lowering carbon emissions and energy use.

The world’s whitest paint formulation was reportedly completed in early 2021. While initially produced for research applications at Purdue, press releases indicate Perdue intends to optimize and commercialize the product for widespread availability as early as late 2023. This rapid early adoption timeline speaks to the hunger for market-viable incremental gains in cooling efficiency as global temperatures continue rising.

With the formulas and methods published openly, it remains to be seen whether alternate whitest paint variants may emerge from other research teams or commercial producers, sparking a global race toward passive cooling innovation. Even moderate cooling boosts from white paint could incentivize entities like major cities to begin budgeting for wide-scale reflective surface projects within the decade.

Applying the world’s whitest paint to building rooftops and envelopes can reduce their surface temperatures by over 20°C compared to conventional options. By reflecting rather than absorbing heat, the broad deployment of the world’s whitest paint could mitigate the phenomenon of urban heat islands, where dense cityscapes absorb and radiate increased warmth. Modeling suggests summer city temperatures could decrease by over 2°C using this approach.

The development of a highly reflective and renewable calcium carbonate-based paint offers an innovative solution to excessive urban heating. As climate change brings more frequent and intense heat waves, the cooling potential of reflective white surfaces will grow increasingly impactful. Deploying this paint across a city’s building stock can lower indoor and outdoor temperatures while cutting air conditioning demands as well. Transitioning rooftops from heat-trapping dark colors to the whitest paint formula could become a climate resilience strategy for communities worldwide.

Looking beyond buildings, custom reflective paints and paving materials show similar potential for cooling everything from vehicles to sidewalks to transit shelters. An urban landscape covered with maximum heat reflection could compound cooling benefits compared to white rooftops alone. More research into expanding high-albedo surfaces across the built environment will further quantify the associated quality of life and emissions reductions. Simple shifts in surfaces and materials at scale could make future cities markedly more livable.

The world’s whitest paint keeps surfaces cool to the touch, even in the hottest environments. Compared to the air temperature at mid-afternoon, a surface painted with the world’s whitest paint can be several degrees cooler than regular white paint. At night, the difference is even more pronounced, up to 19 degrees.

The corresponding drop in air conditioning electricity demand is equally significant from an emissions reduction perspective. Studies by the US Environmental Protection Agency show cool roofs can reduce a building’s annual air conditioning requirements by 10-30%. The increased grid energy efficiency will provide critical flexibility for integrating renewable energy sources as part of essential decarbonization efforts across the power sector.

While the world’s whitest paint’s exceptional solar performance will justify further optimization before mass production, its imminent commercial arrival heralds a shift in leveraging incremental materials innovation. The compound benefits of collective small-scale action represent meaningful progress, offering pragmatic climate hope. If cool paint alone makes summers more bearable, our combined creative efforts focused first on the possibly more than the ideal may yet brighten prospects for sustainable living.

With vision and patience, Perdue’s ultra-white paint is but a glimpse of a future where green cities are dotted with communities that thrive in the hotter world they’ve warded off, one roof at a time.

Source Happy Eco News

Low Carbon 3D Printed Homes – Lower Cost too

Posted on November 23, 2023 by dishanth

An emerging application of 3D printing technology is fabricating entire homes through additive manufacturing. Early adopters demonstrate that 3D printing residential buildings carry significantly lower embedded carbon than conventional construction methods.

By optimizing materials and printing processes, 3D home printing could provide affordable, efficient, low-carbon housing to growing populations if adopted at scale.

Also known as additive manufacturing, 3D printing builds structures by depositing materials layer by layer according to digital models. Concrete is typically extruded through a moving print nozzle onto a substrate, hardening upon deposition to gradually form walls and roofs of low carbon 3D printed homes.

Companies pioneering low carbon 3D printed homes include Icon, SQ4D, and Mighty Buildings. Their printed concrete or polymer designs streamline manual labor of framing, insulation, and finishing. Architectural designs are also easier to customize versus cookie-cutter manufactured units.

But the sustainability benefits are among the most significant advantages over current construction. Architect Sam Ruben, an early adopter of 3D printing for eco-homes, states that 3D printing can reduce lifecycle emissions by over 50% compared to standard building techniques.

Part of the savings comes from more efficient material usage. Conventional construction methods are wasteful, generating excessive scrap materials that go to landfills—3D printing deposits only the needed amount layer-by-layer, eliminating waste.

Printing also allows easier integration of recycled components like crushed concrete aggregate into prints, diverting waste streams. And lightweight printed structures require less embedded energy to transport modules. Optimized print geometries better retain heat as well.

But the biggest factor is speed – printed homes can be move-in ready in days rather than weeks or months. A standard SQ4D home prints in just 8-12 hours of machine time. Accelerated production means less energy consumed over the total construction period.

And speed has financial benefits, too, reducing the logistical costs of prolonged projects. Combined with simplified labor, 3D printing can cut estimated construction expenses up to 30%. Those cost savings make printed homes more accessible to low-income groups while stimulating large-scale adoption.

To quantify benefits, Mighty Buildings completed a life cycle assessment comparing their printed composite polymer dwellings against conventional homes. They estimated their product cut emissions by over one-third during materials and construction. Waste production dropped by over 80%.

Such data helped the company achieve third-party verified EPD declarations certifying their low carbon 3D printed homes. Mighty Buildings believes printed homes could eliminate over 440 million tons of carbon emissions if comprising 40% of California’s housing needs by 2030.

Despite advantages, barriers remain to limit widespread 3D printed housing. Printed buildings still require finishing like plumbing, electrical, windows, and roofing. Developing integrated printing around and including those elements will maximize benefits.

High upfront printer costs also impede adoption, though expected to fall with scaling. And building codes need updates to cover novel printed structures despite proven duribility. Some jurisdictions like California are pioneering efforts to add low carbon 3D printed homes as approved models in housing codes.

But if technical and regulatory hurdles are resolved, additive construction could offer meaningful emissions cuts. With global populations projected to add 2 billion new urban dwellers by 2050, low carbon 3D printed homes may become a go-to sustainable building technique, especially in growing developing countries.

The urgent need for dense, low-carbon housing solutions to accommodate global populations makes 3D printing’s advantages stand out. Printed homes advance from gimmick to viable strategy against climate change.

Eco-conscious homebuyers on a budget have a new choice – low carbon 3D printed homes made from low-carbon cement. A new housing tract in Round Top, Texas has introduced small dwellings printed using concrete that produces just 8% of the carbon emissions of traditional Portland cement manufacturing.

Habitat for Humanity last year unveiled its first low carbon 3D printed home in Williamsburg, Virginia. The project represented Habitat for Humanity’s first completed 3D printed home in the country.

By combining 3D printing techniques with more sustainable cement mixtures, homebuilders can reduce the carbon footprints of affordable printed housing even further.

Source Happy Eco News

Transparent Solar Panels: a Powerful Alternative to Glass

Posted on October 10, 2023October 10, 2023 by dishanth

In the foreseeable future, transparent solar panels hold the potential to take the place of conventional windows, although several challenges must first be overcome. Transparent solar panels are crafted from materials that permit visible light to pass through while capturing the sun’s energy to generate electricity. This unique feature grants them an aesthetically pleasing advantage over traditional, bulky, and opaque solar panels.

However, the best technologies still have lower efficiency than their traditional counterparts, resulting in lower electricity generation per square meter. Moreover, the cost exceeds that of traditional ones, making them less economically viable for the majority of consumers.

Transparent solar panels are made of a transparent material, such as titanium dioxide or amorphous silicon. These materials allow visible light to pass through while still absorbing some of the energy to generate electricity. This makes transparent solar panels more aesthetically pleasing than traditional solar panels, which can be bulky and opaque.

They are still in the early stages of development, but they have the potential to revolutionize the way we generate electricity. They could be used to power buildings, cars, and other devices without taking up any extra space. For example, transparent solar panels could be used to create solar-powered windows that would allow natural light to enter a building while also generating electricity. They could also be used to create solar-powered car roofs or windows that charge the car’s battery whenever it is exposed to sunlight.

They will make economic sense in larger applications despite their lower power-generating capacity. For example, a large high-rise building with good solar exposure could have all the windows facing the sun made with solar panels instead of glass. On a large surface area, this would provide a significant amount of power to run the systems in the building. When combined with high-efficiency LED lighting, regeneration from elevators, and energy storage, the building could become energy neutral or even a net producer.

Numerous companies are vigorously working on enhancing the efficiency and affordability of glass solar panel windows. Successful advancements in this direction could potentially position transparent solar panels as a practical alternative to traditional windows in the future.

Here are some companies actively involved in developing transparent solar panels:

SolarWindow Technologies: Pioneering the field, SolarWindow Technologies has created a transparent solar panel utilizing a thin film of titanium dioxide. This material absorbs sunlight and converts it into electricity. The company claims its transparent solar panel boasts 90% transparency and has the capacity to generate up to 10 watts of electricity per square meter.
PolySolar is a company that specializes in the development and manufacturing of transparent solar panels. PolySolar’s transparent solar panels are made of a thin film of cadmium telluride (CdTe), which is a semiconductor material. CdTe is a very efficient material for absorbing sunlight and converting it into electricity. PolySolar’s transparent solar panels are also very transparent, allowing up to 80% of visible light to pass through.
Onyx Solar is a company that specializes in the development and manufacturing of transparent solar panels. Onyx Solar’s transparent solar panels are made of a thin film of amorphous silicon (a-Si), which is a semiconductor material. a-Si is a very transparent material, allowing up to 80% of visible light to pass through.

These companies represent just a glimpse of the ongoing efforts to develop solar panel windows. With continued research and development, it remains promising that glass solar panels will eventually emerge as a compelling option for replacing windows in the future.

Source Happy Eco News

Using Bio-Based Materials to Build Cities

Posted on August 16, 2023 by dishanth

Did you know about 56% of the world’s population live in cities? The population numbers of urban dwellers are expected to double by 2050 when nearly 7 out of 10 people will live in cities. Cities are polluted due to industrial and motorized transport systems that rely on fossil fuels. The infrastructure that makes up cities is also constructed with carbon-intensive materials. As a result, cities account for over 70% of global carbon dioxide emissions.

We can’t eliminate these systems that make up our cities, but we can use bio-based materials to make them more sustainable. Carbon emissions could be significantly reduced if just a small percentage of new infrastructure in cities is constructed using sustainable bio-based materials. Moreover, these new buildings could also boost carbon storage and help us reach net zero.

Bio-based materials are catching on in the construction industry. They are materials that grow or are a natural part of the biosphere. Bio-based materials include Timber, straw, hemp, cork, clay, and earth. Besides being honest, these bio-based materials are renewable and have a lower, neutral, or negative embodied energy and carbon than traditional construction materials. Timber, for example, has around three times less embodied carbon than steel and over five times less than concrete.

The construction industry accounts for more than 39% of energy and process-related global carbon emissions. Using timber for building, it can store carbon rather than emit it. The Stockholm Wood City will be built in Sickla, Sweden, and is said to be the world’s biggest wooden city. Wooden construction means a significantly reduced climate impact during the construction phase and the whole life cycle. It also has a faster and quieter construction process.

Another bio-based material emerging in the construction industry is algae. Algae are being used in building facades as a sustainable way to generate heat and biomass for various purposes. The algae act like double glazing, but there is water and algae instead of air between the two panes. The algae will also absorb carbon dioxide and insulate the structure.

Hempcrete is a composite material made from hemp hurds, lime, and water. It is a strong, lightweight, and fire-resistant material that can be used for a variety of building applications, such as walls, floors, and roofs. Hempcrete is considered to be a carbon-negative bio-based material. It absorbs more carbon dioxide from the atmosphere than it produces during its production and use. Further, the production of hempcrete also requires less energy than the production of traditional building materials, such as concrete.

Because hempcrete is a good insulator, it can help to keep buildings cooler in the summer and warmer in the winter. This means that less energy is needed to heat and cool buildings, which reduces the amount of carbon dioxide that is emitted into the atmosphere.

Kenaf is a type of fiber that is made from the stems of the kenaf plant. It is a strong, durable, and lightweight fiber that can be used to make a variety of building materials, such as bricks, panels, and insulation.

Miscanthus is a type of grass that is grown for its biomass. It can be used to make a variety of building materials, such as boards, panels, and insulation.

Other benefits of using bio-based materials in the construction industry are that it helps to stimulate local economies, job creation, biodiversity and reforestation efforts. Using natural materials can help provide affordable and sustainable housing at scale.

While getting the entire construction industry on board with bio-based materials is challenging, some countries are trying to ensure this becomes the norm. The French government has ruled that any public construction financed by the state must contain at least 50% bio-based materials. Amsterdam requires that 20% of the city’s housing projects be constructed with bio-based materials starting in 2025.

As cities and population sizes grow, we will see a rise in carbon emissions. If the construction industry turns to using bio-based materials, there is a chance that we will see healthier cities and a healthier planet over time.

Source – Happy Eco News

Building’s hard problem – making concrete green

Posted on May 14, 2021 by dishanth

A time-travelling Victorian stumbling upon a modern building site could largely get right to work, says Chris Thompson, managing director of Citu, which specialises in building low-carbon homes.

That’s because many of the materials and tools would be familiar to him.

The Victorian builder would certainly recognise concrete, which has been around for a long time.

The world’s largest unreinforced concrete dome remains the one at Rome’s Pantheon, which is almost 2,000 years old. The Colosseum is largely concrete too.

Today we use more concrete than any substance, other than water.

That means it accounts for about 8% of the carbon dioxide (CO2) we emit into the atmosphere. That is substantially more than the aviation industry, which makes up about 2.5% of emissions.

The Pantheon in Rome – almost 2,000 years old and built from concrete. GETTY IMAGES

But some companies are developing concrete that has a much lower CO2 impact.

Citu is building its headquarters in Leeds from a new low-carbon concrete that it says cuts CO2 emissions by 50% compared to traditional concrete.

It has used 70 cubic metres of it for the building’s foundations.

Some buildings, like this one in Mexico, are being constructed using Cemex’s low-carbon concrete. CEMEX

This concrete, released last year by Mexico’s Cemex under the label Vertua, is one of a series of recent developments helping pave the way to greener concrete.

Making cement, which makes up 10-15% of concrete, is a carbon-intensive process. Limestone has to be heated to 1,450C, which normally requires energy from fossil fuels and accounts for 40% of concrete’s CO2.

This separates calcium oxide (which you want) from carbon dioxide (which is the problem).

This calcium oxide reacts further to form cement. Grind some into powder, add some sand, gravel and water, and it forms interlocking crystals.

Voilà, concrete.

So how can you do all this without releasing so much CO2?

Karen Scrivener has been working on a way to replace some of the cement in concrete. EPFL

One way is by replacing much of the conventional cement with heated clay and unburnt limestone, says Karen Scrivener, a British academic and head of the construction materials laboratory at Switzerland’s Ecole Polytechnique Fédérale de Lausanne.

For a long time, people (think, Romans) knew you could substitute some of the cement with ash from burning coal (or volcanoes). Or more recently, slag from blast furnaces. This even improved concrete’s strength and durability.

Prof Scrivener was approached by Prof Fernando Martirena from Cuba, who thought it might be possible to use clay in the production of concrete.

So together they worked out a way to replace a really big chunk of conventional cement, and produce equally strong concrete.

Not only would that mean 40% less CO2, it also works with existing equipment, according to Prof Scrivener.

And that’s crucial for a material that has to be competitively priced.

Two companies last year began commercially cooking up this product, called LC3 (for limestone calcined clay cement).

“I reckon next year about 10 plants are going into operation, and really we can see an exponential take-off after that,” she says.

A further 10-20% savings on CO2 emissions can come from finding new ways of making cement more reactive, she adds.

Often people pour in more cement than they actually need, to get early strength.

But if you put in very tiny amounts of other minerals instead, that seems to increase the reactivity too, she says.

Another approach is just coming up with an utterly different way to clench the sand and stone particles together, without cooking limestone into calcium oxide.

This is what Vertua does, says Davide Zampini, head of research for Cemex, the world’s second biggest building materials business.

“It’s a binder that’s rich in aluminosilicates (minerals made from aluminium and silicon), and we have produced chemicals to activate those, and go through a reaction called geopolymerisation,” he explains.

This forms a 3D network of molecules, and a solid binder to grip sand and stone in place.

But it’s not as cheap as conventional concrete, admits Dr Zampini.

You have to find a customer who is really keen on significantly reducing the CO2 footprint of their buildings, he says, like Citu in Leeds.

Cement firms are experimenting with towers like this one which catch the CO2. LEILAC

A third approach is using a big steel tube, says Daniel Rennie, co-ordinator of a project called LEILAC (Low Emissions Intensity Lime and Cement).

It’s 60m (197ft) tall. You can add it to an existing cement plant.

You “chuck materials down from the top” and it gently floats down the tube, which is heated from the outside.

As CO2 comes off the particles, “we just capture it at the top, the calcium oxide continues to the bottom and continues its journey in the cement-making process,” he says.

The project is run by Calix, an Australian company that makes environmentally sustainable technology for industry.

Once captured by the tower the CO2 is compressed and stored in an empty oil reservoir. LEILAC

The company had been thinking about how to decarbonise another building material.

“And just, the penny dropped, and we could apply this to cement,” Mr Rennie says.

A little pilot tower, built in 2019, is now accounting for 5% of production at Heidelberg Cement’s Lixhe plant in Belgium.

This is capturing about 25,000 tonnes a year of CO2.

In Germany, they’re building one at another Heidelberg plant in Hanover, where 20% of total production will go through the new process, capturing about 100,000 tonnes of CO2 a year.

Once captured, the CO2 is compressed, shipped in a barge to Norway, and stored in an empty oil reservoir under the North Sea.

Normally “90% of the cost is capturing the carbon”, so this just leaves the cost of transport and storage.

Innovations that were just ideas 20 years ago are now taking hold in the concrete industry, says Claude Loréa. JOHNNY BLACK

“I’ve been in this industry 20 years, and I really see a big change,” says Claude Loréa, cement director from the Global Cement and Concrete Association.

“Stuff we dreamed about 20 years ago is now coming through,” she adds.

And cement makers have already reduced their carbon emissions “almost by 20% since 1990”, she says, largely by making kilns more energy-efficient.

Still, while we can probably get overall CO2 emissions down by 60-80%, we’ll still end up with some we’ll need to capture and store, says Prof Scrivener.

Also, there’s no point looking for intricate solutions that can just be used in “some very sophisticated factories in the US”, she says.

Around 90% of future cement production will take place outside the wealthy OECD countries.

A concrete path to cutting concrete’s carbon emissions needs alternatives that will work well and cheaply for the coming building booms in India and Africa.

Concrete may have been born in Rome and Britain.

But China made more concrete between 2011 and 2013 than the US did in the whole 20th Century.

By Padraig Belton – Technology of Business reporter

Source BBC