Germany’s Grid: Renewables-Rich and Rock-Solid

Grid graph German Energy TransitionLast Friday Germany’s grid regulator released the 2013 data for grid reliability, and the figures have renewable energy advocates crowing. The latest numbers (released in German) reveal no sign of growing instability despite record levels of renewable energy on the grid — 28.5 percent of the power supplied in the first half of 2014. In fact, Germany’s grid is one of the world’s most reliable.

According to the Bundesnetzagentur, unplanned outages left the average German consumer without electricity for 15.32 minutes in 2013, down from 15.91 minutes in 2012 and 21.53 minutes in 2006. The performance, using the power industry’s System Average Interruption Duration Index (SAIDI), affirms Germany’s place in the top five for grid reliability for European countries.

German grid reliability, meanwhile, far outstrips the best SAIDI results delivered by U.S. and Canadian utilities. The top quartile of SAIDI results captured by last year’s North American reliability benchmarking exercise by the IEEE Power & Energy Society, for example, had consumers without power for an average of 93 minutes — six times longer than outages experienced by the average German consumer.

What makes Germany’s grid reliability notable is the repeated insistence by critics of renewable energy that blackout risk is rising under the German Energiewende or ‘energy transition’. As Craig Morris, lead author of the Berlin-based German Energy Transition, writes this week: “The news may come as a surprise to international critics of the Energiewende.”

Morris highlights one critical piece published by the Washington, D.C.-based Institute for Energy Research on the day that the Bundesnetzagentur released its data. The free market, fossil fuel-oriented group argues that German laws driving the installation of relatively clean but intermittent energy sources such as wind turbines and solar panels have already caused a “destabilization of the grid.”

The outcome of the Energiewende, predicts the group, will be “a higher potential for blackouts.” As Morris’ post this week notes, the most likely reason for Germany’s grid reliability is the preponderance of underground lines in the distribution networks. Over 80 percent of Germany’s low-voltage lines and over 90 percent of its medium-voltage lines are underground. Other European countries scoring high on SAIDI have similar preponderance of underground distribution, including Denmark, Switzerland and the Netherlands, according to a December 2013 reliability assessment from the Brussels-based Council of European Energy Regulators.

For Germany to maintain its reliability, it may ultimately need a lot more lines. A December 2012 study by the Berlin-based German Energy Agency or DENA found that continued growth in renewables would require 135,000-193,000 kilometers of new lines by 2030, and the upgrading of another 21,000-25,000 km. Stephan Kohler, DENA’s CEO, raised doubts that distributors could handle that €27.5-42.5 billion investment, despite financing mechanisms provided by the Bundesnetzagentur to spur investment: “The Federal Network Agency legally mandated an attractive profit. However, our study reveals that in practice the profits from increasing integration of renewable energy systems … are not adequate for the distribution grid operators to survive.”

Upgrades are, however, proceeding at the transmission level. Germany’s transmission operators are planning a set of internal high-voltage direct current (HVDC) lines that are expected to help distribute wind power generated in the North to consumers in the South, and to help push excess solar generation in the opposite direction.

The controllability of those HVDC lines should also be a boon for Germany’s neighbors. North-South power flows regularly loop out of Germany’s grid and hitch a ride over neighboring transmission grids instead. That’s an added burden that Poland, in particular, doesn’t need. While German consumers enjoy the highest levels of reliability, those in neighboring Poland suffered through an average of 254 minutes of unplanned outages in 2012. In other words, Poland’s grid operators have all the work they need just managing their internal system challenges.

This post was created for Energywise, IEEE Spectrum’s blog on green power, cars and climate

Floating Wind Turbines Headed for Offshore Farms

PrinciplePower.WindFloatFloating wind power is no longer science fiction. Promising results from five test platforms operating worldwide—including three in Japan—are turning into project plans for a first generation of floating wind farms. Industry analyst Annette Bossler, who runs Bremen, Maine-based Main(e) International Consulting, predicts that the number of test platforms will nearly double over the next two years and that commercialization is within site. “By 2018-2019 you will start to see the first really large-scale commercial use of floating platforms,” predicts Bossler.

Putting wind turbines on offshore platforms akin to those developed for the petroleum industry provides a means of exploiting high-quality offshore winds—which are stronger and more consistent than onshore winds—in waters too deep for today’s bottom-fixed foundations. Continue reading

Broken Bats: Wind Power and the Damage Done

Last year, IEEE Spectrum profiled an ultrasonic alert for wind farm operators designed to let them know when bats are nearing their turbines. The potentially bat-saving technology can’t be ready soon enough according to this week’s issue of the journal Bioscience. University of Colorado ecologist Mark Hayes estimates that at least 600 000 and possibly more than 900 000 bats were killed by wind turbines last year in the U.S.

Hayes’ report is a statistical reassessment of data on bat carcasses found at wind turbine sites. His figure lends credence to a March 2013 mortality estimate of 880 000 deaths per year by Sacramento-based ornithologist and consultant Shawn Smallwood. That figure was well beyond previous estimates, which had ranged as low as 33 000. “My estimates, using different methods and data, bracket Smallwood’s 888 000 estimate,” writes Hayes in an e-mail to Spectrum. Continue reading

Germany Jumpstarts the Supergrid

05OLGermanGridMap

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.

Building-in a Force of Nature

Turbine House: Design by Michael Pelken & Thong Dang

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.

The Debate: Fracking and the Future of Energy

France 24 Energy in 2013 DebateThe Arctic is melting faster than predicted. Is now the time to shut down the low-carbon nuclear power plants in France — the 20th Century’s staunchest proponent of nuclear energy? Is natural gas produced via hydraulic fracturing or ‘fracking’ a gift that is buying time for a transition to renewable energy or a curse that reinforces fossil fuel dependence? Will carbon belching heavyweights such as the U.S. and China ever get serious about cleaning up their energy systems?

Such questions are top order in France, whose President kicked off a Grand Débat on energy this month Continue reading

Electrical Upgrade Prescribed for Japan’s Crimped Grid

An advisory body for Japan’s powerful Ministry of Economy, Trade and Industry (METI) has endorsed a tripling of the capacity to pass power between Japan’s otherwise estranged AC power grids: the 50-hertz AC grid that serves Tokyo and northeastern Japan, and the 60-hertz grid that serves western Japan. This frequency divide hascomplicated efforts to keep Japan powered since the March 2011 earthquake and tsunami — a task that keeps getting harder with the inexorable decline in nuclear power generation (at present just one of Japan’s 54 reactors is operating). Continue reading