The good news is that engineers are beginning to accept that they have a complex system problem on their hands — an insight that could help them find solutions.
Such understanding was in short supply one year after the Northeast blackout, as I discovered with the publication of my August 2004 cover story for IEEE Spectrum commemorating its one-year anniversary profiling the apparent mathematical inevitability of cascading power-system failures. That message raised a firestorm of protest from engineers who saw their can-do creed under attack.
Today, however, the black sheep who spotted the tell-tale signs of a chaotic self-organizing system in blackout databases have come in from the cold. The University of Wisconsin’s Ian Dobson, for example, says he is having success attracting grants — no mean feat for interdisciplinary research targeting the uber-unsexy field of power transmission. And the IEEE set up a task force on cascading failures (with Dobson at the table).
One obvious cause for rising consciousness is the fact that blackouts just keep happening Continue reading →
Community-gardening advocates have sold urban farming as a sustainable local alternative to industrial-scale farming and as an educational platform for healthier living. And municipalities are buying in, adopting urban ag to transform vacant lots into productive civic assets. In the last two or three years, however, entrepreneurial urban farmers have opened a new frontier with a different look and operating model than most community gardens. Their terrain is above the ground, not in it. Working with help from engineers, architects, and city halls, they have sown rooftops and the interiors of buildings worldwide. “There’s a lot of activity right now, and there is huge potential to do more of it,” says Gregory Kiss, principal at Brooklyn-based architecture firm Kiss + Cathcart. Continue reading →
Can a U.K. firm’s novel plant design defuse environmental concerns?
By Peter Fairley
Fifty years ago this July, Électricité de France began sealing off Normandy’s La Rance estuary from the sea. After three years of work, the world’s first large-scale tidal power plant was born. The station operates still, generating up to 240 megawatts of renewable power as the twice-daily tides force water in and out of the estuary through the hydroturbines seated within its 750-meter-long seawall. But the three years of construction were tideless, which devastated La Rance’s ecosystem, killing off nearly all of its marine flora and fauna; it would take another decade for the estuary to bounce back. Due in part to that ecological hangover, La Rance would remain the only tidal station of its scale for nearly five decades …
Excerpted from the July 2013 edition of Spectrum Magazine. Get the full scoop via Spectrum.
Germany’s bold transmission plan is a go. The Bundesrat, Germany’s senate, has accepted the plan’s enabling legislation forwarded to it by the Bundestag (Germany’s parliament), according to the authoritative German Energy Blog. There is every reason to expect that the plan’s core element — four high-voltage direct current or HVDC transmission lines profiled by Spectrum last month — will get built.
That is good news for Germany’s grid and those of its neighbors. All are straining to manage powerful and variable flows from the wind turbines and solar panels that provided 12 percent of Germany’s power generation last year.
Elements of both the HVDC system design and the legislation should ease construction of the HVDC systems. On the design side, Germany’s transmission system operators have specified advanced converters whose ability to arrest and clear DC line faults will reduce the risk of running overhead lines. This means the HVDC lines can use existing rights-of-way used by AC lines. In fact, they can be hung from the same towers. Read the May 2013 story for extensive discussion of the advanced modular multilevel converters.
The enabling legislation, meanwhile, will simplify line permitting by making a federal court in Leipzig the only forum for legal disputes concerning the projects. Separate legislation passed by the Bundesrat and Bundestag makes Germany’s federal networks regulator, the Bundesnetzagentur or BNetzA, the sole permitting authority for power lines that cross Germany’s state or national borders. These measures — for better or worse — cut out state-level officials that face greater pressure from local project opponents and may be more sympathetic to their concerns.
Add it all up and Germany is en route to become the first country with HVDC lines playing a critical role at the core of their power grid. It is arguably the first real challenge to AC’s century-plus reign as the top dog in power transmission since DC-advocate Thomas Edison lost the War of Currents. Tesla and Westinghouse may just be rolling over.
This post was created for Energywise, IEEE Spectrum’s blog on green power, cars and climate
Sabotage: GreenSource’s how-to guide for occupants
New technology lets occupants work with building systems rather than against them, to improve their comfort while reducing energy costs. By Peter Fairley
The stats on occupant comfort are disappointing, and green buildings are no exception. Consider, for example, heating and cooling performance. Thermal-comfort standard standards stipulate that such systems should satisfy at least four out of five occupants. “Very few buildings actually perform that well,” according to John Goins with the Center for the Built Environment (CBE) at UC Berkeley. Out of the 609 buildings in CBE’s database, only 13 percent meet ASHRAE’s performance threshold; among those that are LEED-certified, 20 percent make the grade.
There is increasing recognition that all that discomfort may be translating into a lot of wasted energy. Goins estimates that the average office building wastes 4 percent of its energy just by cooling and heating more than occupants want. The indirect impact could be even bigger when one considers how disgruntled occupants—who in most buildings lack an effective channel for requesting change—fight back against the machine. They may block air vents or plug in space heaters to combat excessive air-conditioning…
Excerpted from the May/June edition of GreenSource Magazine. Read the story at GreenSource.
Power Core: Spectrum’s infographic take on Germany’s HVDC transmission plans
New developments in high-voltage DC electronics could herald an epic shift in energy delivery
By Peter Fairley
Stuttgart is one of the last places you’d expect to find in a power pinch. This south German city’s massive automotive plants run 24-7 without a hiccup, efficiency measures have held industrial power consumption flat, and solar panels flash from atop its major buildings. But now all that is at risk. The country’s accelerated shift from nuclear power and fossil fuels to renewable resources, such as wind and solar, has exposed a huge gap in its transmission capacity. If they are to survive, Stuttgart’s factories—and power consumers across southern Germany—will need to import a lot more power from the north, and Germany’s grid is already at capacity.
To fill the gap, Germany is considering an aggressive plan that would push high-voltage direct current, or HVDC, from its conventional position on the periphery of AC grids to a central role. The primary reason is simple: For the first time, HVDC seems cheaper than patching up the AC grid. But Germany’s transmission planners also have another motivation: They want to provide as much performance and reliability as they can to an AC grid that’s already strained by excess wind power. For that, they’re considering implementing power electronics that are capable of doing something that’s never before been done on a commercial line: stop DC current in milliseconds flat.
Germany’s plan could mark the beginning of something much bigger: a “supergrid” of inter connected DC lines capable of transporting electricity on a continental scale, ferrying energy from North Sea turbines, dams in Scandinavia, or Mediterranean solar farms to wherever demand is greatest at that moment…
Published in the May issue of IEEE Spectrum. Read the story at Spectrum.com.
Turbine House: Michael Pelken & Thong Dang’s residence with horizontal-axis wind turbine
As design teams work toward harnessing air flows around buildings, they are producing some intriguing structures. But just how viable is wind power as a source of on-site renewable energy? By Peter Fairley
Wind power is the fastest-growing source of megawatts thanks to the jumbo-jet-sized turbines sprouting en masse worldwide. But it also has a significant presence in the city, where gusts regularly send umbrellas to landfills. Rather than considering it a nuisance, architects increasingly view urban wind as a renewable resource for on-building power generation.
Building-integrated wind power (BIWP)—wind turbines mounted on or incorporated within an occupied structure—may lack wind farms’ economies of scale. But like the leading source of on-building renewables—photovoltaics (PVs)—wind turbines offer some advantages in architectural applications. No roads get cut through wilderness to erect towers, and they deliver electricity without power lines and transmission losses. Wind turbines are also attractive to designers and clients looking to express a commitment to sustainability.
Such benefits provide potential for dramatic growth, says mechanical engineer Roger Frechette, principal in the Washington, D.C., office of Interface Engineering. “If there’s data showing that BIWP works and testimony that it’s a good thing to do, there will be an explosion,” he predicts…
Published in the April 2013 issue of Architectural Record Magazine. Read the whole story.