ABU DHABI, United Arab Emirates -- What does it take to build a zero-carbon, zero-waste city?
Four years into the Masdar Initiative, a grand plan by the United Arab Emirates to create a new "greenprint" for urban design, developers are finding that the necessary elements include a stable of the world's brightest minds, plenty of cash, and a stomach for trying over.
Masdar City was launched in 2006 with an announcement that the government of Abu Dhabi, an oil- and natural gas-rich emirate of the United Arab Emirates, would build a city just outside the capital demonstrating a new way of living with sustainable technologies.
"We will do this by completely re-engineering the way modern cities are built and use energy," Masdar CEO Sultan al Jaber told the U.S. House Select Energy Independence and Global Warming Committee during a presentation in 2008, adding that Masdar was designed to consume a quarter of the power needed by a conventional city of the same size.
The city -- really more of an industrial park, with a research institute to anchor the hoped-for hive of technology startups and energy powerhouses -- is being built in stages over several years at a cost initially estimated at $22 billion.
The endeavor has leadership from the highest levels of Abu Dhabi's government, which is committed to diversifying the emirate's economy outside of fossil fuels (Greenwire, April 19).
The master plan for the project was developed by Foster + Partners, a British architecture firm with a portfolio of landmark buildings.
Designed to recall traditional Arabic architecture, the plan calls for a walled city with narrow, shaded streets. Lining those streets, buildings are to blend time-tested strategies for battling the desert heat with the most modern technologies.
The first building to be completed will house the Masdar Institute for Science and Technology's laboratory and living space, and that structure is the only one visible on the site today (Greenwire, April 21).
As big as a city block, the building is partially clad in curving, terra cotta-colored panels that recall the privacy screens used throughout the Muslim world, traditionally to shield women's quarters while providing a view of the outside. In addition to decoration, the screens serve a practical purpose in limiting the hot sunlight that passes inside.
Other "passive" technologies are designed into the city layout as well, planners say. Streets will be oriented on diagonals that block some of the area's hot daytime winds and maximize cool nighttime breezes. Wind towers, based on a centuries-old technology that draws warm air over a water reservoir to cool it and provide indoor ventilation, are planned throughout the city.
The central high-technology at play is solar power, a natural choice given the desert location. Many of the city's buildings were designed to incorporate rooftop solar panels, and land is set aside for large-scale solar installations as well.
After testing a range of photovoltaic panels, the developers settled on a 10 megawatt solar field to start off. Reportedly the largest such plant in the Middle East, it was built at the project's outset to fuel construction. Officials said the field's output is metered as it flows into Abu Dhabi's electrical grid, and construction and staff commuting emissions are calculated against that amount.
A Masdar contractor, Jay Witherspoon of construction firm CH2M Hill, recently called that storyline into question when he told Abu Dhabi's the National newspaper that some conventional energy use is not yet being offset. Water taken from Abu Dhabi's central utility is desalinated with copious amounts of electricity, and Witherspoon said project managers are tracking that usage now and could balance it later with a desalination project elsewhere in the emirate.
"By the time the city is built out, we will be carbon-neutral," Witherspoon told the newspaper.
But while planning for the project shows numbers lining up neatly, build-out has forced revisions.
The most visible is to the city's transportation scheme. The original design barred conventional vehicles from the walled perimeter. Visitors who drove up to Masdar would park their cars and hop into a "personal rapid transit," or PRT, pod. Those vehicles, driverless and all-electric, would pilot passengers robotically, guided by magnets embedded in the roadway.
The PRT pods were all the rage as recently as January, when reporters converged on Masdar City for the World Future Energy Summit. Engineers showed off prototype pods, and visitors wondered at the air quality to be expected in a car-free metropolis.
But a few months later, Masdar officials took a step back from that promise. "We need to look at whether it works," said Fares Ghneim, Masdar's chief of communications, in a telephone interview.
Ghneim said London's Heathrow Airport uses a similar system but that one is limited to a narrow path. The scheme devised for Masdar was to run throughout the city, which is more complicated.
"One limitation is that it prevents having anything else where the tracks run," Ghneim explained. If other vehicles ran on the PRT lane, they would obscure the magnets and confuse the guiding sensors. Also, he said, committing heavily to the PRT system might not make sense just as efficient new electric and hybrid vehicles are entering the marketplace.
For now, the PRT system is being implemented just around the Masdar Institute campus. The system is sure to draw interest and generate experience with the technology, but Ghneim admitted that within that limited area, walking might be just as effective a way to travel.
In a similar vein, other technology-based ideas have slammed against realities on the ground.
Originally, the city plan called for wind turbines to provide much of the electric power. But as Nawal Al Hosani, an architect by training and the associate director of sustainability with Masdar's property development group, explained, tests showed that the wind speeds were not fast enough to be very useful. Also, she said, the site's location next to Abu Dhabi's airport meant that turbines could not be built high enough to catch the strongest winds.
Al Hosani said initial plans to top most of the city's rooftops with solar panels have also run into barriers, first and foremost the high cost.
While project developers have deep pockets, she said, there are limits, so the effort needs to be commercially viable at some level. "Some of the new technologies are going to be on the expensive side, but at the end of the day it can't be ridiculously expensive," she said.
As a result, concentrated solar photovoltaics, which channel sunlight from many mirrors or other capture devices onto a single collector, are being investigated in more depth. Officials said the technology is being tested for local conditions; photovoltaic systems typically do well in yearlong sunshine like Abu Dhabi's, but performance can suffer in sandy or dusty environments if the collectors are obscured.
A newer push is for geothermal energy to play a major role in Masdar's power production: Drilling tests started this spring a stone's throw from the temporary office trailers.
Kevin Healy, the marketing manager for Al Hosani's property management division, said he is optimistic that water will be found that can be put to work. If the water is very hot, it could be used to generate electricity, while if it is somewhat cooler, it could serve the city's need for water heating and dehumidification.
Healy said it will take about six months to get an answer from the test wells. But drilling is expensive, with the cost tied closely to how deep wells must go -- a question that as yet remains unanswered.
Another potential power source lies in pairing some of Abu Dhabi's abundant natural gas with enhanced oil recovery to yield low-carbon energy.
Hydrogen Power Abu Dhabi, a joint venture between Masdar and BP PLC, aims to generate 400 megawatts of energy -- more than 5 percent of all Abu Dhabi's current power generation capacity, according to the companies -- in what they say would be the world's first commercial-scale, hydrogen-fueled power plant.
The plant would reform natural gas into hydrogen and carbon dioxide. The hydrogen would be burned to make electricity, while the CO2 would be piped to a nearby oil field and used to boost yields.
Officials said plans for the hydrogen power plant are largely on track. Some delays to the $2 billion project have been announced over the past year, but key commercial agreements are expected to be reached this summer, with a final project decision slated for next year and plant commissioning in 2015.
Al Hosani, the project's sustainability chief, said the planning team does not yet know what the city's daily power draw will be when it is fully built out. But the pressure is clearly on to come up with the right mix of solutions.
Ghneim said Masdar's technology strategy aims to balance an embrace of new technologies with cost and the need for systems to actually work, and pulling back from some early choices reflects those realities.
Pointing to solar photovoltaic panels as a field that is evolving particularly fast, he said, "If you buy them all today, by the time you reach the later phases, there might be new technologies."
"We need to take a pragmatic approach," Ghneim added. "With what we're building today, or at any particular moment, [we will] integrate and use technologies that are reliable and that are proven and that are cost-effective. That doesn't mean we can't explore new technologies," he said, but "it does take time to prove things, and only once they're proven will they be integrated on a large scale into the project."
Ghneim said planners are also examining the cost of importing renewable power. A concentrating solar power plant could be built elsewhere in Abu Dhabi, he suggested, with the power piped into Masdar City. He also did not rule out a move toward using renewable energy certificates or another form of offset projects to meet the city's carbon-free power commitments.
"The aim and the commitment is there -- that has not changed," Ghneim said. "The answers aren't there yet."
Waste not, want not
The waste side of Masdar's sustainability commitments is, in comparison, simpler.
During the construction phase, officials have arranged to reuse as much of the building material as possible. Dirk Boysen, site logistics lead with CH2M Hill, described how used metals are recycled, while wood is chipped and used in landscaping or burned, and discarded concrete is crushed and reused in roads. Waste water is similarly hoarded, treated and recirculated for irrigation.
During a drive through the construction site, Boysen pointed out a football field-sized area where piles of used material sat awaiting reuse, noting that he had never worked on a project that took such measures.
Inside Masdar's temporary office space, waste management is notably low tech: Employees do not have trash bins at their desks but do have recycling containers. Throwing something away requires getting up and walking to a central area, where there are also receptacles for compostable trash. Boysen said when the system was first set up employees were put off by it, but before long they adjusted.
It is unclear how much behavior change of this type will be asked of city residents down the road, as planners have stressed that the city will not reflect the hardship and self-denial often linked with environmentalism. But the same hierarchy of composting and recycling will take place on the back end to minimize the city's waste stream once residents move in.
Planners also hope to wring electrons from the zero-waste commitment, in the form of waste-to-energy technology. Blueprints are open to any of three approaches: gasification, pyrolysis or plasma arc gasification.
Waste-to-energy technologies are appealing and are used successfully in some countries. But in the United States, they have failed to take off in the past, in part because of local opposition and in part because proponents have struggled to show they generate more energy than they consume.
'Platform for innovation'
With its solar, wind and geothermal power technologies, plus energy efficiency, carbon sequestration and green building design, Masdar City hits virtually all the high notes of sustainable energy. Given such a wide-ranging approach, it should perhaps come as no surprise that some options are proving better than others.
Today, planners are in the first phases of construction on a very long project -- the city's completion date, originally announced as 2016, has been stretched indefinitely as officials stress the need to grow "organically" with market forces. Success will hinge in part on their ability to convince funders, and the world at large, that less-than-expected results are not failure and that pressing forward with new technologies is, in itself, success.
That argument will be easier to make if Masdar shows signs of growing into the kind of innovation hub that its leaders hope for.
Masdar's CEO has called the city "a platform for innovation" and stresses that the end goal is economic development with Abu Dhabi becoming an exporter of sustainability technologies.
"The long-term aim is to create a broad range of innovative industries that will generate a steady flow of new ideas and technologies and advances," said Masdar Chairman Ahmed Ali al Sayegh. "These industries will transform Abu Dhabi's economic role and will contribute to the development of national and regional economies."