European Grid Operators 1, Solar Eclipse 0

Solar forecast for March 20 via Energy-Charts.de, with previous days' generation

Solar forecast for March 20 from Energy-Charts.de, with prior days’ solar output

Weather forecasts calling for bright sun today across Europe drove up tensions in advance of the partial solar eclipse that blocked the sun’s rays and plunged much of the continent into a brief period of darkness this morning. Grid operators were bracing for record swings in solar power generation because of the celestial phenomenon. Some power distributors in Germany had warned of fluctuations in frequency, notifying customers and suggesting that they shut down sensitive equipment.

In the end, while clear weather made for some excellent eclipse viewing, the electrical story ultimately felt more like Monty Python’s radio coverage of the 1972 eclipse. As if audio coverage of a quintessentially visual event isn’t absurd enough, the Pythons closed their fictitious report in the ultimate anticlimax, as a sudden rainstorm swept in to spoil the solar spectacle. Europe’s interconnected power grid brought about an equally anticlimactic ending today by delivering rock-solid stability throughout the 2.5-hour eclipse.

In fact, according to Enrico Maria Carlini, Head of Electric System Engineering for National Dispatching at Rome-based transmission system operator Terna, the grid was more stable than normal. Carlini had joked last week about doing a rain dance to dampen solar output during before and after the eclipse. Today he took satisfaction from the fact that the frequency of Europe’s power barely budged from its 50 hertz standard.

If transmission system operators had been struggling to keep power capacity and demand in balance during the eclipse, the frequency would have diverged strongly from 50 hertz. But according to Carlini, it strayed only ±25 millihertz all morning, which he says is about the half of normal variability in Europe’s grid frequency.

The grid rolled over the solar swings partly because they were smaller than the worst case scenarios for which operators had been preparing for many months. In all, Europe lost and regained about 17 gigawatts of solar power generation this morning, according to the European Network for Transmission System Operators for Electricity (ENTSO-E) in Brussels. That is a lot of power—just shy of the total solar capacity installed across the United States as of the start of 2015—but just half of the swing that ENTSO-E had warned of in its February eclipse analysis.

TSOs thus confronted the possibility of solar swings with overwhelming force. German TSOs had double the normal personnel on hand in their control rooms. They also had enough gas- and coal-fired power capacity on standby to double the effectiveness of their standard contingency plans for keeping the grid balanced, says Bruno Burger, an expert in renewable energy integration at the Fraunhofer Institute for Solar Energy Systems in Freiburg. “The TSOs really massively prepared,” says Burger.

Today’s solar swings still represented the biggest power gyrations that Germany’s TSOs have ever confronted, according to Burger. Germany’s solar generation was at nearly 13 GW when the lunar shading began. At the peak of the eclipse, at around 10:30 CET, it had crashed to just 5.4 GW. Then, by noon, it had rushed back up to about 20 GW. That post-eclipse surge would have soaked up about 50 percent more than the maximum negative power reserve capacity that Germany’s TSOs had in place in 2013 and 2014. “This was a big challenge for the TSOs,” says Burger.

Still, they could have handled plenty more, claims an analysis (in German) by Burger’s group, which estimates that Germany’s power installations can provide up to 25.6 GW of regulating capacity per hour. Bloomberg reported today that TSOs called up only about 30 percent of the balancing power that plant owners tendered.

Terna, whose Italian power plants are less conventional than the ones its German TSO counterparts can call upon, took an additional measure to balance this morning’s eclipse-driven solar swings: For the first time ever, it exercised its authority to order the nation’s largest, most advanced solar power plants to regulate themselves.

“Those plants were ordered to limit their output to about 30 percent of total capacity from 7 am to 2 pm CET,” says Carlini. That action, he says, reduced the solar power deflation during the eclipse by about 500 megawatts and trimmed the post-eclipse rebound by 2 GW. Under Italian law, solar plant owners will absorb the lost revenue because this was an “emergency procedure,” says Carlini, who doesn’t expect that authority to be wielded again before the next eclipse in 2027..

Burger says Germany’s TSOs could have also shut down solar capacity, but chose not to because German law requires TSOs to compensate the solar plants. An analysis by Berlin-based research group Energy Brainpool estimated that would be more expensive than ramping fossil-fired power plants up and down. As reported by PV Magazine yesterday, shutting down solar generation could nearly triple the cost of handling the eclipse to €9.95 million (US$10.7 million).

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

Solar Eclipse Will Test European Power Grids

imgA partial eclipse of the sun headed for Europe next Friday has grid operators in a tizzy. On the morning of March 20 Europe’s skies will darken for the first time since solar power became a meaningful piece of some countries’ power supply, and the impact could be dramatic.

“It’s a very, very big challenge for the transmission system operators in Europe,” says Enrico Maria Carlini, Head of Electric System Engineering for National Dispatching at Rome-based Italian transmission system operator Terna.

The Brussels-based European Network for Transmission System Operators for Electricity (ENTSO-E) judges in an eclipse impact analysis released last month that it poses a, “serious challenge to the regulating capability of the interconnected power system.”

While an eclipse markedly reduced solar generation in western North America last October according to energy tracking firm Opower, Europe’s far greater levels of solar power make for bigger stakes. ENTSO-E projects that the moon’s jaunt across the sun’s path next Friday could slash more than 30 gigawatts (GW) of solar generation in Continental Europe over one hour if clouds are scarce and solar generation is high. That’s the equivalent of turning off 30 big coal or nuclear power stations. Continue reading

Censors Take On China’s Silent Spring Moment

Jinhua skyline 2005c

Jinhua skyline, 2005

Chinese censors took down a hugely popular documentary on China’s air pollution crisis this past weekend, according to reports by the Wall Street Journal and the New York Times. Under the Dome, a polished, 104-minute report by Chinese broadcast journalist Chai Jing [embedded below], had gone viral after its release last week, attracting several hundred million views in China before censors restricted domestic access to the video and squelched news coverage of it.

The film is a damning account of China’s declining air quality, the sources of its pollution, and the toothlessness of environmental agencies charged with controlling it. It’s a wide-ranging production that tries to explain the price China has paid for its industrialization and wealth generation, as well as a passionate call to action.

For me, the film’s visceral portrayal of contemporary life amidst smog—and the movie’s historic sweep—sparked flashbacks to my own discomfort breathing in Chinese air during visits in 1991, 2005, and 2006.

In 1991, my eyes burned as the aging cruise liner I’d taken over from Japan motored up the Huangpu River, past the petrochemical plants then lining the river’s eastern banks, on its way into Shanghai. But the historic city across the river was clean. Aside from a few buses, it was a city that still moved on pollution-free pedal power, its streets a flood of bicycles. And as I traveled inland for several weeks, the pollution faded further, revealing China’s natural beauty.

When I flew into Shanghai 14 years later to report on China’s rising tide of electric bicycles for IEEE Spectrum, Shanghai itself seemed still cleaner than I’d recalled. While cars and trucks were on the rise, the East-bank industry had been cleared to make way for gleaming skyscrapers.

But China was clearly changing. I visited smaller cities where smog nearly blocked out the sun. Continue reading

EPA Coal Cuts Light Up Washington

A meeting at the U.S. Federal Energy Regulatory Commission’s (FERC’s) Washington headquarters yesterday lived up to expectations that it would be one of the most exciting sessions in the agency’s history. Buttoned up policy wonks, lobbyists, and power market experts showed up in droves—over 600 registered—to witness a discussion of what President Obama’s coal-cutting Clean Power Plan presaged for the U.S. power grid. The beltway crowd was joined by activists for and against fossil fuels—and extra security.

Inside proceedings, about the Environmental Protection Agency (EPA) plans’ impact on power grid reliability, protesters against fracking and liquid natural gas exports shouted “NATURAL GAS IS DIRTY” each time a speaker mentioned coal’s fossil fuel nemesis. Outside, the coal industry-backed American Coalition for Clean Coal Electricity distributed both free hand-warmers and dark warnings that dumping coal-fired power would leave Americans “cold in the dark.”

As expected, state regulators and utility executives from coal-reliant states such as Arizona and Michigan hammered home the ‘Cold in the Dark’ message in their exchanges with FERC’s commissioners. Gerry Anderson, Chairman and CEO of Detroit-based utility DTE Energy, called the Clean Power Plan “the most fundamental transformation of our bulk power system that we’ve ever undertaken.”

EPA’s critics argue that the plan’s timing is unrealistic and its compliance options are inadequate. Anderson said Michigan will need to shut down, by 2020, roughly 40 percent of the coal-fired generation that currently provides half of the state’s power. That, he said, “borders on unachievable and would certainly be ill-advised from a reliability perspective.”

EPA’s top air pollution official, Janet McCabe, defended her agency’s record and its respect for the grid. “Over EPA’s long history developing Clean Air Act standards, the agency has consistently treated electric system reliability as absolutely critical. In more than 40 years, at no time has compliance with the Clean Air Act resulted in reliability problems,” said McCabe.

McCabe assured FERC that EPA had carefully crafted its plan to provide flexibility to states and utilities regarding how they cut emissions from coal-fired power generation, and how quickly they contribute to the rule’s overall goal of lowering power sector emissions by 30 percent by 2030 from 2005 levels. (Michigan has state-verified energy conservation and renewable energy options to comply with EPA’s plans according to the Natural Resources Defense Council.)

McCabe said EPA is considering additional flexibility before it finalizes the rule, as early as June. EPA would consider, for example, specific proposals for a “reliability safety valve” to allow a coal plant to run longer than anticipated if delays in critical replacement projects—say, a natural gas pipeline or a transmission line delivering distant wind power—threatened grid security.

As it turned out, language codifying a reliability safety valve was on offer at yesterday’s meeting from Craig Glazer, VP for federal government policy at PJM Interconnection, the independent transmission grid operator for the Mid-Atlantic region. The language represents a consensus reached by regional system operators from across the country—one that is narrowly written and therefore unlikely to give coal interests much relief. “It can’t be a free pass,” said Glazer.

A loosely-constrained valve, explained Glazer, would undermine investment in alternatives to coal-fired power, especially for developers of clean energy technologies. “Nobody’s going to make those investments because they won’t know when the crunch time really comes. It makes it very hard for these new technologies to jump in,” said Glazer.

Clean energy advocates at the meeting, and officials from states that, like California, are on the leading edge of renewable energy development, discounted the idea that additional flexibility would be needed to protect the grid. They pushed back against reports of impending blackouts from some grid operators and the North American Electric Reliability Corporation(NERC). Those reports, they say, ignored or discounted evidence that alternative energy sources can deliver the essential grid services currently provided by conventional power plants.

NERC’s initial assessment, issued in November, foresees rolling blackouts and increased potential for “wide-scale, uncontrolled outages,” and NERC CEO Gerald Cauley says a more detailed study due out in April will identify reliability “hotspots” caused by EPA’s plan. At the FERC meeting, Cauley acknowledged that “the technology is out there allowing solar and wind to be contributors to grid reliability,” but he complained that regulators were not requiring them to do so. Cauley called on FERC to help make that happen.

Cleantech supporters, however, are calling on the government to ensure that NERC recognizes and incorporates renewable energy’s full capabilities when it issues projections of future grid operations. They got a boost from FERC Commissioner Norman Bay. The former chief of enforcement at FERC and Obama’s designee to become FERC’s next chairman in April, Bay pressed Cauley on the issue yesterday.

Bay asked Cauley how he was going to ensure that NERC is more transparent, and wondered whether NERC would make public the underlying assumptions and models it will use to craft future reports. Cauley responded by acknowledging that NERC relied on forecasts provided by utilities, and worked with utility experts to “get ideas on trends and conclusions” when crafting its reliability studies.

Cauley also acknowledged that they were not “entirely open and consensus based” the way NERC’s standards-development process was. And he demurred on how much more open the process could be, telling Bay, “I’ll have to get back to you on that.”

The challenge from Bay follows criticism leveled at NERC in a report issued last week by the Brattle Group, an energy analytics firm based in Boston. Brattle found that compliance with EPA’s plan was “unlikely to materially affect reliability.”

Brattle’s report concurred with renewables advocates who have argued that NERC got it wrong by focusing too much on the loss of coal-fired generation and too little on that which would replace it: “The changes required to comply with the CPP will not occur in a vacuum—rather, they will be met with careful consideration and a measured response by market regulators, operators, and participants. We find that in its review NERC fails to adequately account for the extent to which the potential reliability issues it raises are already being addressed or can be addressed through planning and operations processes as well as through technical advancements.”

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

Will Shuttering Coal Plants Really Threaten the Grid?

Does President Obama’s plan to squelch carbon emissions from coal-fired power plants really threaten the stability of the grid? That politically-charged question is scheduled for a high-profile airing today at a meeting in Washington to be telecast live starting at 9 am ET from the Federal Energy Regulatory Commission (FERC).

Such “technical meetings” at FERC are usually pretty dry affairs. But this one could be unusually colorful, presenting starkly conflicting views of lower-carbon living, judging from written remarks submitted by panelists.

On one side are some state officials opposed to the EPA Clean Power Plan, which aims to cut U.S. power sector emissions 30 percent by 2030 from 2005 levels. Susan Bitter Smith, Arizona’s top public utilities regulator, argues that EPA’s plan is “seriously jeopardizing grid reliability.” Complying with it would, she writes, cause “irreparable disruption” to Arizona’s (coal-dependent) power system.

Environmental advocates and renewable energy interests will be hitting back, challenging the credibility of worrisome grid studies wielded by Bitter Smith and other EPA critics. Some come from organizations that are supposed to be neutral arbiters of grid operation, such as the standards-setting North American Electric Reliability Corporation (NERC). Clean energy advocates see evidence of bias and fear-mongering in these studies, and they are asking FERC to step in to assure the transparency and neutrality of future analyses. Continue reading

Does Hawaii Need a Unified Grid?

Power cables to Oahu could reduce curtailment of Maui wind farms. Credit: First Wind

Since 2013, a big mainland energy firm has been raring to build Hawaii’s first inter-island power cable, arguing that only a unified power grid can enable the renewable energy developments needed to break Hawaii’s addiction to imported petroleum. Now that big outsider—Juno Beach, Florida-based NextEra Energy—is trying to absorb Hawaii’s power providers in one big bite.

In December, NextEra announced plans for a friendly $4.3 billion acquisition of Hawaiian Electric Industries, which owns the vertical monopolies that run the archipelago’s island grids (with the exception of Kauai’s). Observers debating what the acquisition would mean for Hawaii’s electrical future see at least three quite distinct outcomes:

  • NextEra secures Hawaiian Electric and builds cables to unify its assets, unleashing renewable energy development
  • NextEra’s bid for Hawaiian Electric is squashed by officials with longstanding mistrust of outside interests, and the island utilities proceed on their own
  • NextEra wins approval for the acquisition but drops its cable ambitions, focusing instead on bringing liquefied natural gas to Hawaii to repower Oahu’s oil and coal-fired generators

Interconnecting the islands is an idea that dates all the way back to an 1881 meeting in New York City between Hawaii’s then-King Kalakaua and Thomas Edison. Kalakaua’s officials asked Edison if electricity could be generated from the Big Island’s active volcano and delivered via subsea cable to Oahu to bring electric light to Honolulu, thus sparing Hawaii greater dependence on Australian coal. Edison said the scheme could work, according to a report by the New York Sun, but demurred that it, “would cost so much, that’s all.”

134 years later, one hears essentially the same arguments for and against a unified Hawaiian grid. Proponents such as NextEra and the Hawaii State Energy Office say Oahu must hook up to its neighbors’ grids because it lacks the renewable resources needed to meet even half of its power demand—over 7,500 gigawatt-hours (GWh) per year, or nearly three-quarters of the state’s total.

Hawaii’s other islands, by contrast, have renewable potential to spare, says a 2010 analysis commissioned by the U.S. Department of Energy’s National Renewable Energy Lab. Lanai and Molokai could each generate over 1,000 GWh per year of wind power; Maui has over 2,000 GWh of viable geothermal, wind, and solar resources; and Hawai’i (better known as the Big Island) has over 6,000 GWh of geothermal potential. Sharing these resources with Oahu via subsea cables, the authors concluded, was the only way to meet Hawaii’s goal to push renewables to 70 percent of the power supply by 2030.

In 2013, NextEra proposed to start with a 180-kilometer-long, high-voltage direct current (HVDC) link between Maui and Oahu dubbed NextGrid Hawaii. Last year, Pacific Business News reported that NextEra had secured property in downtown Honolulu for the converter station where NextGrid’s pair of 200-megawatt cables would come ashore and link up with Oahu’s AC grid.

NextGrid would cost an “enormous” $600-800 million, according to Pacifc Business News, but NextEra said it would save the islands’ utilities at least $4.8 billion over its first 40 years of operation. The State Energy Office conservatively pegs net savings to consumers at a more modest $423 million, plus $128 million in environmental benefits.

One source of savings is avoided ‘curtailment’ of wind farms on Maui, which already produce more power at times than the local grid can handle. Hawaiian Electric’s Maui subsidiary ‘curtailed’ 20.6 GWh of wind generation last year. (Kauai’s utility expects to begin curtailing solar power generation this year.)

The promise of better renewable energy utilization earned NextEra support from some environmental groups. “We’re stronger together,” says Jeff Mikaluna, executive director for the Honolulu-based Blue Planet Foundation. In addition to better integrating renewables, says Mikaluna, tying the islands together should also reduce the need to keep fossil fueled power plants running in reserve.

NextGrid also appears to be spurring interest in cables to other islands, such as the Big Island. That island’s biggest landholder, the historic Parker Ranch, says a cable to Oahu could benefit a pumped hydroelectricity storage project it is developing. “Parker Ranch could enable a large-scale storage solution as part of an integrated statewide grid,” wrote Parker Ranch CEO Neil Kuyper inan August 2014 press release.

Of course, as is usually the case for transmission proposals, the idea of inter-island cables also has its critics. Some question, as Thomas Edison did, whether cables will really pencil out economically. Henry Curtis, executive director for Honolulu-based environmental advocacy group Life of the Land and a blogger on energy issues, says technical challenges associated with laying power cable over steep subsea slopes could inflate project costs.

Curtis also questions the cables’ environmental benefits, and highlights potential environmental harm. NextEra’s Maui-Oahu cable, for example, would traverse a humpback whale sanctuary.

And cables might ultimately prove unnecessary if advances in grid and power generation technologies expand Oahu’s indigenous renewable resources. Smarter inverters, for example, are helping Oahu’s grid cope with increasing levels of distributed solar energy. Curtis says more energy may be available just offshore, citing the ocean thermal energy converter currently being tested by Hawaii-based Makai Ocean Engineering.

Distributed generation advocates, meanwhile, are raising alarms about the track record of NextEra subsidiary Florida Power and Light (FPL), the utility that serves most of Florida. In December, Greentech Media noted that Florida ranks 29th in the country for overall renewable energy development, and blamed FPL for the sun-soaked state’s shortage of solar power: “It’s not for lack of sunshine; it’s lack of policy. Florida has no renewable standard—FPL has crushed every effort to establish one.”

Energy analyst William Pentland raised similar alarms in Forbes last month. “Hawaiians should think long and hard about NextEra’s track record in the Sunshine State before approving any merger,” writes Pentland.

NextEra is, for its part, playing the grid unification card close to its chest as Hawaii’s regulators weigh its offer for Hawaiian Electric. One thing appears certain: NextEra will face heightened expectations to deliver on Hawaii’s renewable energy aspirations if the acquisition goes through.

Blue Planet Foundation’s Mikaluna says Hawaiian Electric was saying what state leaders wanted to hear at the state capitol earlier this week. During a hearing on a bill proposing a 100-percent-renewables standard for Hawaii’s utilities for 2040, Hawaiian Electric’s representative abandoned the utility’s traditional tack. Rather than hedging on the prospects for zeroing-out fossil fuel consumption, the new message was ‘How about 2050?’ “That’s a first,” says Mikaluna.

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

Japan Seeks to Rein In a Solar Juggernaut

Clashing energy interests on the Japanese island of Kyushu have prompted Japan’s government to clamp down on solar power development nationwide. While the government calls it a necessary revision to assure grid stability amidst rapidly rising levels of intermittent solar energy, critics see a pro-nuclear agenda at work—one that could stunt Japan’s renewable energy potential.

Solar development in Japan has exploded since the Fukushima nuclear disaster of 2011. Thanks to an attractive feed-in tariff (FIT) program that guarantees premium rates for renewable power generation pushed through in the disaster’s aftermath, developers have since installed over 10 gigawatts of solar capacity. The solar surge marks a return to glory for the country that once dominated the global PV industry.

But Japan’s solar revival has occurred under a cloud. The pro-nuclear Liberal Democratic Party regained power in late 2012, intent on restarting idled nuclear reactors that once generated nearly one-third of Japan’s electricity. The nuclear cloud produced its first lightning bolts on Kyushu in September, and has now spread nationwide. Continue reading