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Detecting and Correcting Methane Leakage: Is a Technical Fix Ahead?

It's fashionable and sensible in the complicated domains where technology and policy intersect to be suspicious of any narrowly conceived solution. "There's no technical fix," goes the usual refrain (which I certainly have voiced plenty of times myself). In the case of methane leakage from natural gas production and distribution systems, however, there really may be a combination of technical fixes on the horizon. Because of methane's high global warming potential relative to carbon dioxide, detecting and correcting methane leakage is going to be very important in the years ahead.

Two and a half years ago, the Maryland company Earth Networks announced it would start building a network of sensors to directly monitor greenhouse gas emissions on a regional basis, working with the Scripps Institution of Oceanography, and others. Each processing unit consists of a US $50 000 box, along with elaborate calibration software that Earth Network has developed with scientific partners at Scripps, NIST and NOAA, and connects by a tube with sensors installed 100 meters up on some existing tower [photo]. The initial plan called for putting about 100 units in the United States, 25 in Europe, and 25 other places in the world.

Earth Networks CEO Robert Marshall says that 28-30 units are now installed, mostly in the U.S. Northeast but also in the Los Angeles area and some other places. One of the company's units has taken over the famous job of monitoring global CO2 atop Hawaii's Mauna Loa and produced the definitive measurement several months ago of the Keeling curve's crossing the 400 ppm threshold.

Earth Networks, originally known as AWS Convergence Technology, makes its living primarily by delivering very finely grained weather forecasts and severe weather alerts. Its well-know trademarked product, WeatherBug, is widely used by clubs, schools, and planners of major sports and entertainment events. Before the terrible Moore, Oklahoma tornado last spring, the company's networks detected dense in-cloud lightning, an early warning signal of the catastrophic twister. As for the greenhouse gas monitoring network that Earth Networks is installing, this work is being done at present on what you might call a pro bono basis—or, if you prefer, as a speculative venture anticipating high future demand for the new service.

These days, says Marshall, there is little demand for GHG monitoring at the national level because there is no real issue of national compliance at present. The system established by the Kyoto Protocol in 1997 has lost traction, and the world awaits a new system of mandatory GHG cuts, to be formulated at a conference in Paris at the end of 2015. But in the meantime, Marshall points out, two regional GHG reduction programs have been established in the United States—in the Northeast and in California—and many cities here and overseas are adopting objectives that will require monitoring.

As the GHG detection networks get built out, they will be able to determine how much methane is escaping from major fracking fields and from aging urban gas distribution systems, to name the two most important situations giving rise to acute concern. At present, reports of emissions from gas fields are often based on one-day spot checks done by aircraft flyovers. "There's nobody else out there doing what we do," says Marshall. "Permanently installing sensors that take data continually and can monitor emissions from an entire gas field, as opposed to just individual wells."

Once the Earth Networks GHG detectors are able to provide alerts to situations where methane leakage is high, then newly developed portable monitors can be used to pinpoint the exact spots where leaks are highest, so that corrective measures can be taken. One such portable device, a "gasbot" developed in Sweden, was described in a recent post here; another, described in a recent New York Times article, was developed by instrument maker Picarro, the same company that makes the Earth Networks GHG boxes. Thus, the region-wide and portable monitoring devices have complementary roles to play so that, to the extent methane leakage turns out to be a really serious problem, it may also turn out to be a fixable problem.

Photo: Earth Networks

Another Very Strong Year for U.S. Wind

Researchers at the Lawrence Berkeley National Laboratory (LBL) have issued their latest authoritative report on the status of U.S. wind energy. Newly installed turbine capacity increased a whopping 90 percent in 2012, driven in large part by subsidies that were expected to expire (but did not); total wind capacity climbed to 60 gigawatts, the equivalent in terms of expected energy production of roughly a quarter of installed nuclear power.

Despite plummeting natural gas prices and wide switching from coal to gas generation, the expansion of wind outstripped gas last year in terms of capacity, though not in terms of expected energy production. The United States narrowly edged out China as world leader in wind capacity additions and left Germany, a one-time world market leader, in the dust.

When wind is considered as a percentage of total electricity consumption, the United States still ranks only twelfth, with Denmark in first place, Germany in fifth, and the UK in eighth. But the scope for potential U.S. expansion is considerable. The United States still has no offshore wind turbines installed, an area where Denmark, Germany, and the UK have led the way.

Many findings in the LBL report indicate a mature technology capable of standing on its own two feet, with predicable costs and returns. Capacity factors—the proportion of time units are generating at rated capacity—have been steady since the beginning of the century at about 30 percent; that is the most important single measure of performance and reliability. Turbine costs came down from about $1.80/watt in the late 1990s to $0.80/W in 2001-02, climbed back up to about $1.60/W a few years later, and now seem to be settling in the vicinity of $1/W. Total project costs, after dropping from more than $3/W in the 1980s to about $1.25 in 2004-05, seen to be stabilizing near $2/W.

Somewhat counter-intuitively, the report found that the biggest economies of scale are registered not for example by very large farms with medium-scale turbines but by small clusters of very large turbines [photo].

Looking both back and ahead, perhaps the most important aspect of wind's impressive performance has been the standard it is setting for solar energy, which also is intermittent and therefore has similar expected capacity factors. At current solar prices, which obviously are artificially low, photovoltaic arrays are being installed at costs similar to wind's—$1/W or less per panel, $2/W or less per project. Only time will tell whether in fact solar also is crossing the boundary to market competitiveness. As of today, according to the environmental reporter for London's Financial Times, PV arrays installed without subsidies account for only a tenth of one percent of total world installations.

Looking to the present and immediate future, the LBL experts expect this year to be somewhat slow for wind, as the project pipeline is rebuilt, but for solid growth to resume in 2014.

Photo: Jodi Jacobson/iStockphoto

Report Counts Up Solar Power Land Use Needs

The National Renewable Energy Laboratory (NREL) released a report [PDF] last week that aimed to quantify exactly how much room solar power requires. Land use and space issues have long been a point of contention when it comes to renewables, with opponents complaining that the huge spaces required for solar and wind aren't worth the effort. The NREL report suggests the acreage required for industrial-scale solar power plants is within the range of previous estimates, and generally doesn't seem off-the-charts outrageous.

“The numbers aren’t good news or bad news,” said Paul Denholm, one of the report's authors, in a press release. “It’s just that there was not an understanding of actual land use requirements before this work." The report used land use data from 72 percent of all large solar plants installed in the U.S., and found that the total area requirements for a photovoltaic (PV) plant between 1 and 20 megawatt capacity is 8.3 acres per MW. For larger PV plants, the total area needed is 7.9 acres per MW, while concentrating solar power plants (CSP) need 10 acres per MW. When weighted by generation rather than capacity, the larger PV plants (3.4 acres per gigawatt-hour per year) and CSP plants (3.5 acres/GWh/year) do a bit better than smaller PV plants (4.1 acres/GWh/year).

This isn't the first time NREL has looked at solar land use, though it is the first time they used a whole lot of actual power plants to figure out the numbers. In the past, they estimated that to power all of the U.S. with solar power, it would require 0.6 percent of all the area in the country. How do the latest numbers stack up with that? To the back of the envelope!

The new report says that a PV plant capable of powering 1 000 homes needs 32 acres. According to the U.S. Census Bureau, there are around 115 million occupied and fully used homes in the country. If we just scale up linearly (which is not, of course, how this would actually work), that means 3.68 million acres to power all of them. That's equivalent to 5 750 square miles, or around 0.1 percent of all the land the US has to offer. Not bad!

Perhaps more relevant is the question of how these land use requirements measure up to other forms of energy. When it comes to renewables, there's no doubt that solar power is far more area-efficient than wind power; an NREL report [PDF] from several years ago found a total requirement of about 84 acres per MW, a far cry from the 10 or so acres that solar seems to max out at. Geothermal energy might be the best of the bunch, though, in the low single digits.

Outside of renewables, things can get a bit complicated. Nuclear power is often considered very area efficient, though mining for uranium could add a complicated factor to that equation. Similarly, coal power plants themselves don't use a ton of space per megawatt generated, but there is little debate on the devastating land use impacts of coal mining. One study looked at what it would take to produce 10 percent and 100 percent of the whole world's power from various sources, and found nuclear and geothermal energy at the very lowest end of area needs, followed by coal, CSP, and natural gas.

Unfortunately, though, we don't yet have government studies similar to the new NREL study that go into each energy source in as much detail. Denholm stressed that doing such studies that use actual, existing plants for coal, nuclear, and natural gas would allow us to more firmly compare which energy sources get us the most bang per acre.

Photo: spg solar / Wikimedia Commons

How Big a Problem is Methane Leakage from Natural Gas Fracking?

By now it should be evident to all that hydraulic fracturing is a disruptive technology in every sense. With natural gas prices still in free-fall because of fracking, competition from gas-fired generation continues to lay waste to plans for new nuclear power—the most recent casualty being Duke's Levy project in Florida—while threatening investment in futuristic green and clean tech. Fracking is the most important single element in the dramatically improved energy position of the United States, and the main factor in the country's much lower greenhouse gas emissions.

The one thing that could slow the gas juggernaut is concern about methane leakage, which, because of CH4's high warming potential relative to CO2, could cancel benefits believed to accrue from conversion of coal to gas generation. There is evidence, however, that concerns about methane leakage may be somewhat exaggerated.

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Electric Car Price Wars Heat Up

General Motors announced on Tuesday it will shave US $5000 off the price of its 2014 Chevrolet Volt, a drop of 13 percent.

The move comes after Nissan cut the price by similar margins for its all-electric Leaf earlier this year, and Ford did the same for its Focus Electric. The Volt could cost as little as $27 495 after federal tax incentives.

The lower costs are due in part to manufacturing efficiencies, Don Johnson, U.S. vice president of Chevrolet sales and service, said in a statement. “We have made great strides in reducing costs as we gain experience with electric vehicles and their components,” he said. “In fact, the Volt has seen an increase in battery range and the addition of creature comforts.”

It may be seen as a pricing war between electric vehicles (EVs), but all of the electric and plug-in hybrids are competing with higher fuel economy internal combustion engines, efficient diesel, and hybrids offerings and steady gas prices just below $4 per gallon in much of the United States.

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UK Launches Europe’s Largest Energy Storage Trial

The largest European energy storage trial is underway in the United Kingdom. The project, which brings together S&C Electric, Samsung SDI, and Younicos, will deploy a 6-megawatt/10 megawatt-hour lithium-ion battery at a primary substation in Bedfordshire to assess the cost effectiveness of energy storage as part of the UK’s Carbon Plan.

The companies claim the storage could save more than US $9 million compared to traditional upgrades, such as replacing lines and transformers. Unlike many other regions, the UK’s deregulated utility market is incentivized towards low-carbon operations in which they are rewarded for better utilization of their existing assets, rather than just adding hard assets onto the networks.

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How Significant Is Methane Leakage?

Over the past six to eight years, the United States has registered quite dramatic decreases in greenhouse gas emissions, putting the country on track to meet its 2009 Copenhagen pledge (though not its 1997 Kyoto Protocol commitment, which it repudiated). The decreases have primarily been the result of energy companies switching from coal-fired electricity generation to natural gas—partly a spontaneous market reaction to very low U.S. gas prices, and partly a reaction to ever-tightening Federal regulation of coal emissions.

But what if those decreases were only apparent because leakage of methane from gas production, distribution, and use has overinflated the supposed benefits of switching from coal to gas? On average, burning gas rather than coal to make electricity cuts carbon dioxide emissions by about 50 percent; the alleged decline in U.S. greenhouse gas emissions since about 2006 is largely based on that assumption. But methane is a much more potent greenhouse gas than CO2—up to two orders of magnitude, or 100-times, more potent. So if there's a lot of methane leakage, the benefits of switching to gas could be nil, and U.S. claims about making big progress in cutting emissions could be wrong.

Several major studies aimed at addressing this key issue are underway. Perhaps the most ambitious in scope is one being conducted by the Environmental Defense Fund (EDF) in conjunction with 85 academic researchers and natural gas companies. The results of the EDF methane leakage study are to be released next year in peer-reviewed science journals. The study covers production, processing, long-distance distribution, local distribution, and the transportation sector.

A preliminary paper on methane leakage by leaders of the EDF study, published in the Proceedings of the National Academy of Sciences, found that if the Environmental Protection Agency's well-to-city leakage estimate of 2.4 percent is about right, then there is indeed a net benefit from switching to gas. In fact, any leakage rate below 3.2 percent will yield a net benefit, say the EDF authors. But it is important to emphasize—you could say crucial—that the issue here is not merely whether switching from coal to gas produces a benefit; the issue is whether it produces a huge climate benefit, as is generally believed.

If the net effect on greenhouse gas emissions of switching from coal to gas is merely modest, then other factors might tip the balance against gas in a comprehensive cost-benefit analysis: factors such as water impacts of fracking (total water resources, drinking water), ramifications for local communities (traffic congestion, air pollution, property values), and long-term investments in other sources of clean energy (from renewables like wind and solar to nuclear energy). This week, Electrité de France (another EDF!) announced it was terminating nuclear work in the United States because of competition from rock-bottom natural gas prices.

The Environmental Defense Fund's methane leakage study is not the only important one underway. A U.S. Environmental Protection Agency assessment of hydraulic fracturing, also due out next year, may address the question of leakage, according to Anthony R Ingraffea, an engineering professor at Cornell. Writing in the New York Times on Monday, Ingraffea said early drafts of an Energy Department study "suggest that there are huge problems finding enough water for fracturing future wells."

Taking those studies into account, 2014 looks to be shaping up as the year in which we Americans learn whether we're good guys or not such good guys in the global greenhouse gas reduction drama.

Photo: Shannon Stapleton/Reuters

Peru Will Provide Solar Power to Half a Million Poor Households

Peru recently launched a new program that aims to bring solar power to more than two million of its rural residents who currently lack access to the grid.

The National Photovoltaic Household Electrification Program has already started its first phase, which installed 1,601 solar panels in 126 communities in Contumaza, a province in the northeastern region of Cajamarca, according to the Latin American Herald Tribune.

“This program is aimed at the poorest people, those who lack access to electric lighting and still use oil lamps, spending their own resources to pay for fuels that harm their health,” said Jorge Merino, Peru’s Energy and Mining Minister.

The program will install 12 500 solar photovoltaic systems to be shared among 500 000 households at a cost of about $200 million over the next five years. United Nation’s Development Program, Peru’s ministry of energy and mines, and the Global Environment Facility will supervise the project, according to PV Tech.

The need for electricity is substantial in Peru, especially in rural areas. Nearly half of more than 24 million Peruvians live in poverty, and one-third of the population lacks access to the electric grid.

Currently, most of the rural solar installations are in homes of people with financial means, according to a World Bank report [PDF] from 2010. But for poor communities, the cost of extending the grid to remote, high-altitude regions can be extremely costly, making solar PV and microgrids more appealing.

According to the report, most households that would use a solar PV system now use car batteries or dry cell batteries to run small appliances and candles and kerosene for lighting.

The project hopes to create a network of small business—like those now supplying kerosene— that will sell, maintain, and operate the PV systems, according to a brief for the UNDP.

Residents will still require some sort of storage for the solar power for when the sun isn’t shining. There could also be an opportunity to form community microgrids in remote areas that connect solar panels with other energy sources (which might not always be clean), such as what EarthSpark International has piloted in Haiti.

Peru’s solar program is part of a larger plan to bring regular electricity access to 95 percent of its residents. The country plans to spend about $3 billion on new electricity generation, according to SolarReviews, including one gigawatt of hydropower, 800 megawatts of gas-diesel, and another 300 megawatts of other renewable energy.


Photo: Julia Manzerova/Flickr

Germany's Largest Offshore Windfarm Hits a Snag

Developers of Germany's first commercial offshore wind farm, located in the North Sea off the famous resort island of Bockum, have run up against a bigger than expected stumbling block: Unexploded ordnance from the Second World War. The explosives on the ocean floor are impeding completion of the connections between the turbines and their intended electricity customers on land.

The 400-million-euro Riffgat project, built by the local utility EWE in cooperation with Enova, will consist of thirty 3.6 megawatt Siemens windmills, each 150 meters high and having a rotor diameter of 120 meters. With a total capacity of 108 MW, the farm is expected to supply about 120 000 customers.

As described in a recent issue of Germany's Die Zeit, although about half the turbines have now been installed, builders are running into problems completing transmission connections on the ocean floor because of unexploded World War II munitions that have to be cleared. (Die Zeit is the country's leading general-interest publication of commentary and analysis.) The problem is not wholly unexpected, to be sure: Workers had to remove roughly 2.7 million metric tons of unexploded ordnance while installing the towers themselves. In total, according to Die Zeit, there are an estimated 1.6 million metric tons of hand grenades, bombs, and artillery shells lying on the ocean floor in Germany's national waters.

Could Die Zeit, a liberal-minded organ of opinion, be exaggerating the problem—or the utility minimizing it? The Riffgat project website included a fair representation of press coverage, including the death of a British diver, killed by a sinking block of construction concrete. But it does not include Die Zeit's article.

photo: EWE

China's New Solar Price

A decade ago, when IEEE Spectrum was preparing a special issue on China's tech revolution, a colleague sitting in an airplane heard somebody behind her exclaim, "But what's the China price?" What he was asking, like everybody in business then and since, was what the Chinese were charging for products in his particular line.

Since Saturday, when the European Union settled a solar trade dispute with China on terms favorable to the People's Republic, we at least seem to know, more or less, what the global floor price for photovoltaics will be in the near future: 56 euro cents per installed watt of photovoltaic cell, or roughly US $0.75/W.

The EU settlement of a trade complaint brought by European PV manufacturers led by Germany's SolarWorld does not impose sanctions or tariffs on China. It does not satisfy the complainants and is seen as weak—typical of Europe's failures to advance its global interests with sufficient resolve. But that's geopolitics, which is a story for another day.

What's of interest here is the settlement's setting of a solar price that's well below the one-dollar-per-watt mark, often considered the breakeven point for PV market competitiveness. It will "allow Chinese companies to export to the EU up to 7 gigawatts per year of solar products without paying duties, provided that the price is no less than 56 cents per watt," as the Financial Times put it in its report. That is, Chinese producers will be permitted to collectively export 7 GW of solar cells to Europe each year—an amount equal to more than half of Europe's solar market—without incurring trade penalties. ("A trade deal with the European Union gives China 60% of the EU's solar-panel market," concludes a video interview on the Wall Street Journal site.)

The 7-GW ceiling on Chinese PV exports to EU states is essentially voluntary: Any exporters exceeding that limit will pay tariffs averaging 47.6 percent, as of August 6. That would seem to almost guarantee that Chinese exporters will not sell to Europeans at a price below 56 euro cents per watt. And, as Europe represents such a large fraction of the global solar market, the global PV floor price will be approximately the same.

In the short run, however, the effect of the European settlement may be that the Chinese will dump PV cells in the U.S. market at an even lower price. That is the opinion of Keith Bradsher, China correspondent for the New York Times, who previously did outstanding reporting about the crisis in the U.S. auto industry and the festering troubles of Detroit.

Photo: William Hong/Reuters



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