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View of Guantonamo Bay's quartet of wind turbines.
View of Guantanamo Bay's quartet of wind turbines which can produce up to 10% of the U.S. Navy base's electric power needs. Photo credit: U.S. Navy.

Matt Simmon's Wind Dreams

Suzanne Sayer envisions how Maine could be a major energy exporter.

By Suzanne Sayer, PhD

Reprinted from the 16 January 2012 edition of Peak Oil Review, published weekly by the Association for the Study of Peak Oil - USA.

By Suzanne Sayer, PhD

During the first Arab oil embargo President Nixon put price controls on petroleum. The next administration successfully launched the first round of energy conservation measures and promoted the development of alternative and renewable energy resources. By the early 1980s oil prices had stabilized, and the GOP in the White House had little interest in continuing the policies of the Carter administration. When President Reagan’s “energy” policy was adopted during the 1980s, R&D in renewable energy resources was neglected. The USA abandoned its position as the most advanced country in the development of alternative and renewable resources. Since then, the Pacific Ring of Fire countries surpassed us in the development of geothermal resources, and northern European countries bested us in wind power, while we focused on petroleum that is ever deeper and more difficult to extract.

The Danes and Germans not only developed technologically advanced wind turbines, they also figured out how to integrate wind power into their national electrical grids using High Voltage DC transmission lines. They consume hydropower from Norway when wind was not blowing, and reverse the power flow when the wind blew. They began to model and understand electrical generation, transmission and distribution systems that integrated wind into their nuclear and coal-based load generation system. With the waning of European oil and gas, a whole wind industry developed in northern Europe leaving us a decade or two behind.

Simmons’ Dream

When Matt Simmons retired he undoubtedly realized that of the fifty states, Maine was the most highly dependent upon petroleum for its energy needs. Over 75% of Maine’s households heat with fuel oil, no doubt he found we were completely dependent on others for our energy needs. Simmons established the Ocean Energy Institute (OEI) and brought his expertise and contacts in the off-shore oil industry to jump start a renewable energy industry in Maine. This state, settled by people who used wind and water for their transportation and trade, has a tremendous wind resource. Looking at wind maps of the continental US, the proximity of abundant offshore wind resources to densely populated areas is clearly evident.

Offshore wind turbines may well attain capacity factors as high as 75% during the winter months when New Englanders need heat (Mays 2012, Personal communication). Investigators at OEI espoused electricity for use in heat pumps or resistance heating saving fuel oil for transportation, the use of electrical vehicles (EV), anhydrous ammonia, and natural gas for transportation and started research on how to store energy and match the resource to the need.

About the same time, the independent system operator of New England (ISO-NE), the independent regional transmission organization (RTO) funded the New England Wind Integration Study (NEWIS). The NEWIS study modeled wind integration in the RTO from 0% wind to 24% wind. The NEWIS study, as well as other studies, laid to rest the myth that wind generation needs to be backed up 100% by spinning reserves. To the extent that some people still believe that 100% backup is required, I refer them to this study.

Here’s how it works. In order to satisfy North American Electrical Reliability Corporation (NERC) regulations for reliability, all RTOs require generation to be backed up by “reserves”. ISO-NE regulations say that the single largest generator in this RTO has to be backed up by at least three different types of reserves in the event it goes off line suddenly.

In addition to generating the needed power and voltage support requirements for the ISO, the largest generator (LG) within the ISO needs to be backed up by: 1) ten-minute spinning reserves for 25% of its generation, 2) 50% of the LG in ten-minute non- spinning reserves, and 3) 100% of second largest generator in 30 Minute operating reserves: the sum of all back up reserves equals the total operating reserve (TOR). That means that of the 21+ GigaWatts (GW) of generation in the ISO-NE region a TOR of 2,250 MegaWatts (MW) (2.25 GW) is needed even without any wind generation at all. If wind generation replaces 2.5% of electrical generation in the ISO the TOR needed would be 2,270 MW or 20 MW more. At 9% wind integration the TOR is 2,600 MW - only 350 MW more than without wind.

In an earlier study (www.uwig.org 2006) the capacity value of wind was found to typically be up to 40%, and the addition of 1500 MW and 3,300 MW of wind increased regulation reserve requirements by 8 MW and 36 MW respectively. These regulations may have changed because of the ERCOT episode described below. It is not credible that all wind turbines in a region will stop instantaneously as would a single large generator.

The UWIG report states: “Because wind and load variability are not statistically correlated, the net increase in variability due to the addition of wind is less than the variability of the wind generation alone, so wind cannot be treated in isolation from the load." In other words there is little need to back up wind generation facilities with fossil fueled “spinning” reserves. In fact, the best spinning reserve for use with wind generation is hydropower followed closely by gas turbines (think jet engines). Steam turbines fueled by coal and nuclear are poor reserves, even for the 30 minute operating reserve, because they cannot be spun up or down, but work as base generation. Electrical loads do not mimic the base generation but ramp up in the evening and down late at night with all sorts of hourly and minute fluctuations. In New England the peak electrical loads typically occur on hot summer days for air conditioning. Solar panels would shave off that peak, and wind would cover much of the lower but more constant winter heating load.

ASPO-USA members might be familiar with the “wind” event on Feb. 26, 2008 in the Electrical Reliability Council of Texas (ERCOT) region. This event was a superposition of three factors only one of which was the wind. The evening load (42 MW/minute) ramped up faster than predicted by ERCOT, the wind expected to ramp down (1500 MW in 3.5 hours), did it faster (8MW/minute rather than 5MW/minute) than predicted by the ERCOT meteorologists. The tipping point came when the conventional generation unit (150 MW), scheduled to come on with the evening load, tripped off unexpectedly, and caused ERCOT to call for an Emergency Electrical curtailment that lasted two hours. This event was widely reported in the press, because it involved wind generation. Similar events using conventional generation have been ignored for the most part. (NREL July 2008) Modeling has shown that the larger the electrical transmission system the easier it is to integrate wind. ERCOT is much smaller than other RTOs. Texas is not connected to the three other electrical interconnected areas in the USA and Canada.

It is obvious that better wind models and predictions are needed to avoid the miscalculations in ramp speed for wind events that added to the ERCOT event. Electricity has to be used at the moment of generation. This presents a unique problem for wind, since it is not dispatchable, meaning that you can’t decide when to use it, you have to use it when the wind is blowing. Modest excess wind electrical wind generation can be stored in electrical flywheels for minutes to hours and in batteries for days or months. Research on variable sized vats of chemicals to store electrical energy is promising. More research into electrical storage is needed before wind can penetrate much more than 20% into the electrical grid for a prolonged period. Dr. O’Malley, an electrical engineer from Ireland, reported that the Emerald Isle has at specific times generated up to 42% of its electrical power from wind and up to 33% for an entire day, and had to spill the wind so as to stay within the operational limits of its grid design.

The US Navy has an aggressive renewable energy goal, because each gallon of petroleum we save will be one less gallon we have to pay for in blood and treasure. They installed three (now four) wind turbines at Guantanamo, saving the taxpayer many thousands of gallons of diesel fuel for generators. The Navy’s 2015 goal is to reduce the non-tactical petroleum use by 50%: their 2020 goal is to have 50% of their shore-based energy requirements come from alternative energy resources. It is widely reported that the cost of diesel in combat areas such as Afghanistan is well over $100/gallon, and most of that fuel is used for electrical power generation.

In support of planned off shore wind farms, Dr. Kempton of the University of Delaware has demonstrated in the PJM RTO how to store excess wind power electrical generation on the order of MWhr in specially designed electrical vehicles (EV). The vehicle batteries provide superior voltage regulation smoothing out the millisecond and minute dips in the voltage signal caused by the constantly fluctuating load. Kemp’s work on EV battery energy storage has been replicated by Xcel Corporation in Boulder, which is doing an advanced study of integrating wind into its service area. Beacon Power has paired its high-tech flywheel regulators with wind farms in NY State, and American Superconductor provides voltage support and regulations to industrial wind farms and solar farms. “System stability studies have shown that modern wind plants with power electronic controls and dynamic voltage support can improve system performance by damping power swings and supporting post-fault voltage recovery”. (UWIG)

Before Matt Simmons’ untimely death in August 2010, he had a vision of offshore floating wind turbines that would gather wind energy and use it to heat Maine’s homes and power its cars. He was also considering using far offshore floating wind platforms to generate hydrogen from water that could then be combined with nitrogen from the air and produce anhydrous ammonia. Large marine vessels could pull up to a floating wind turbine farm fill their fuel tanks with anhydrous ammonia and transit the oceans using modified diesel engines. Matt was well aware that anhydrous ammonia fueled diesel vehicles in Norway in the 1920s and in Belgium during WWII, and envisioned land based ammonia fueled vehicles. Anhydrous ammonia has about one third the energy density of gasoline, but in naval applications it might suffice in a carbon-constrained future.

Suzanne Sayer, PhD, affiliated with the Maine Wind Industry Initiative, currently earns a living as a nuclear engineer. In the 1970s she worked on research in geothermal energy at Los Alamos prior to her career as a petrophysicist/geophysicist at Sohio in San Francisco.

Bibliography
http://www.iso-ne.org/pubs/whtpprs/irc_assess_plugin.pdf
http://biodieselinafghanistan.org/uploads/AFGH-PAPR-20100609-EXEC.pdf
http://www.iso-ne.com/committees/comm_wkgrps/prtcpnts_comm/pac/reports/2010/index.html
http://www.uwig.org
http://www.purepowerd.com/emergency.htm
http://www.nrel.gov/wind/systemsintegration/pdfs/2008/ela_ercot_event.pdf

Times Article Viewed: 17737
Published: 16-Jan-2012

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