US turbines dismal at 1.3% Energy Production

Unbridled Energy: Predicting Volatile Wind, Sun Utilities Ramp Up Focus on Forecasting When Renewable Fuel Is at a Peak to Avoid Squandering Power That Still Can't Be StoredBy JEFFREY BALL
For more than a century, producing power has been a matter of flipping a switch. Need more electricity? Fire up some fuel. Need less? Dial the flame back down.

Things won't be that easy in a world that gets much of its energy from renewable sources, which come and go at nature's whim. Wind tends to blow hardest at night -- a problem, since people use electricity mostly during the day. Sunshine can lose its intensity in seconds if eclipsed by a cloud -- inconvenient for people who like their air conditioners to run steadily on summer days.


To harness renewable energy more reliably, some companies are experimenting with ways to story energy when the output is high and then distribute it when output is low. WSJ's Jeff Ball reports on the efforts to build a better battery.
Many states and countries are pledging to produce 20% or more of their electricity from renewable sources within about a decade. That will be a major stretch. The recession has severely crimped renewable-energy investment. Proposals to turn over large swaths of desert and coastline to renewable-energy generation are encountering angry opposition. And the drop in fossil-fuel prices has removed much of the public appetite for a big renewable-energy bid. Yet those very pressures are pushing renewable-energy proponents to pursue their goal as efficiently as possible. And so the search for ways to accommodate the vicissitudes of wind and sun continues to shape up as one of today's great technological quests.

A convenient solution would be to overcome wind and sun's intermittence by storing the energy and then dispensing it later, on windless or overcast days. But storage technology is still embryonic.

So the power industry is having to change the way it operates. To adapt its fossil-fuel-dependent infrastructure to renewable energy's ebbs and flows, it is trying to forecast them better. Knowing how nature is likely to behave will help the industry better balance different sources of renewable energy, scientists and utility executives say. The goal: maximizing wind, sun and other natural sources when each is at its peak.

The Inconstant Wind
View Interactive

Largely due to the unpredictability of the heavens, the thousands of wind turbines across the country collectively produced 1.3% of actual electricity in 2008.
Currently, every wind farm and solar installation has to be backed up by a nearly equivalent amount of conventional fuel to keep the power grid running. That raises costs.

"We're putting renewables into a system that wasn't designed for renewables," says Paul Denholm, an analyst for the federal government's National Renewable Energy Laboratory, in Golden, Colo.

Wind power is the fastest-growing renewable source of electricity. Buoyed by government mandates and subsidies, wind farms accounted for more than half of all net electricity-generating capacity added in the U.S. in 2008, according to the Department of Energy.

But capacity to produce is not actual production. Largely due to wind's unpredictability, the thousands of wind turbines installed across the country collectively produced only 1.3% of actual U.S. electricity in 2008, the department's figures show.

The Bonneville Power Administration, a government-owned utility based in Portland, Ore., taps one of the biggest collections of wind farms in the country. Between January and August, average wind-power production accounted for 12% of average electricity consumption in Bonneville's service area.

From hour to hour, though, wind power swings wildly depending on how things blow at the Columbia River Gorge, where most of the wind turbines in Bonneville's service area are located.

This Tuesday was typically erratic. At 1 a.m., wind farms in the Bonneville service area were cranking out about 1,550 megawatts of power. By 7 a.m., that fell to about 800 megawatts, just as people were waking up and turning on their lights and toasters. That night, once most people were asleep, the wind picked up again. By 11:45 p.m., wind power topped 2,000 megawatts.

Most of the electricity in Bonneville's service area comes from hydroelectric power. To compensate for the volatility of wind, Bonneville tweaks the amount of water it lets through the dams. But that doesn't work for the most extreme shifts in wind. Sometimes, when the wind is blowing hard, Bonneville releases extra water over the tops of dams without using it to generate electricity. Otherwise, electrical wires might get overloaded. And when the wind is so strong that Bonneville can't ditch enough water, the utility orders wind turbines shut off.

"Everything changes with wind," says Bart McManus, a wind expert at Bonneville.

Sudden doldrums can be as troublesome as sudden gusts. That was the problem on Feb. 26, 2008, in Texas, which produces more wind power than any other state.

At 3 p.m. that afternoon, Texas's wind farms, concentrated in the western part of the state, were throwing off about 2,000 megawatts of electricity, enough to serve about one million households. Then a cold front blew in. By 6:30 p.m. -- when electricity demand typically peaks -- wind production in Texas had cratered to about 360 megawatts.

Exacerbating matters, Texans began turning up their heat -- much of which, in rural parts of the state, comes from electricity.

The operator of Texas's electrical grid, the Electric Reliability Council of Texas, known as Ercot, scrambled. It cut off power to various industrial customers that, in exchange for payment, had agreed to let Ercot pull their plugs in emergencies.

To avert situations like these, Ercot has hired a company to provide, every hour, a forecast of how the wind will blow at every wind project on the Ercot grid. It requires wind-power producers to install gauges that feed into those forecasts.

Related Reading
A major difficulty in harnessing the wind to generate electricity is that the wind is unpredictable. The Bonneville Power Administration, a utility in the Pacific Northwest, provides a continuously updated readout of wind-power generation in its service area. The readout shows how erratic the wind can be.Texas, one of the nation's top wind-power-producing states, unexpectedly lost a massive amount of electricity when a cold front blew in on the afternoon of Feb. 26, 2008. The Department of Energy explains what happened that day in this report. America's capacity to generate electricity from renewable sources, such as the wind and sun, is growing fast. But renewable energy remains a tiny slice of the overall energy pie, as the Department of Energy shows in this July report.Wind power now provides just 1.3% of U.S. electricity, but it could provide as much as 20% by 2030 if "significant challenges" are overcome, the Department of Energy said in 2008 in a report.The forecasts look not just at temperature, but also at wind speed and direction at the height of wind turbines, an altitude that until now hasn't attracted much interest.

If there were a viable way to store large amounts of renewable energy, Ercot might have been able to tap it on that February afternoon. Investors and the government are backing storage development. One hope is a better battery. Other ideas include systems that would store water in uphill sites or compressing air underground, for later release when electricity is needed.

So far, these are largely experimental. Making renewable energy big, many studies suggest, would require a combination of approaches: investment in high-voltage transmission wires to carry renewable electricity from remote areas to cities; policies to encourage energy efficiency; and coordinated construction of renewable facilities so that one form of energy can fill in when others are dormant. In many places, wind is calmest at midday, when solar power is most available.

For now, better renewable-energy forecasting is important. Today's forecasts remain frustratingly inexact. Just after midnight on Christmas morning, 2007, an unexpected wind surge hit in Colorado, a state with a lot of wind turbines. It sent power production soaring on the system operated by Xcel Energy, a utility that is trying to improve its wind forecasts.

"We were walloped," says Tom Imbler, vice president of commercial operations for Minneapolis-based Xcel. To compensate, Xcel scrambled to dial down some of its fossil-fuel power plants. Those plants "were never designed to ramp up and ramp down at the level we're asking them to" in the age of renewable energy, he says. "We're learning as we go."

Turbines not so Eco-Friendly

Sunday 04th of October 2009
Reports Suggest Wind Turbines Could Kill Wildlife
Posted on: October 2nd, 2009 by Beth Williams
Some reports now suggest that wind power may not be as eco friendly as everyone wants to make it out to be. Sure it helps in terms of cutting down on carbon emissions, but what does it do to the wildlife? Some experts say that these wind turbines could spell out problems for some animals.

As of right now there is no denying the fact that wind turbines are linked to bat and bird morality. The wildlife ecologist and ornithologist, Albert Manville, has claimed that wind turbines cause 440,000 bird deaths every year in the United States. The number of bird deaths is thought to be so high due to the fact that the wind currents, that are needed to make wind turbines turn, are the same wind currents that billions of birds use to migrate across the United States. This adds just another problem for species of birds that are already at risk from habitat degradation.

However, other studies are very quick to point out that, no matter what kind of energy people used, it could possibly put some wildlife in danger. After all, it is worth pointing out that birds and bats do fly right into cooling towers and oil platforms as well. On top of this, the extra carbon emissions that are generated by coal fired generators are, by far, a greater danger to all wildlife, not just birds.

Of course, some of the wind farms that are being put up in the UK are far less dangerous to birds. This goes double for wind farms that are located offshore. Bats, for the most part, do not fly over the ocean very much. It also appears that offshore wind turbines seem to cause a lot less bird deaths.

Geology and Sea Level Change

Examples of the different volcanic flow units and evidence of past higher sea-levels and possible future sea-level rise impacts



Tim Webster, PhD

Applied Geomatics Research Group

COGS, Middleton

timothy.webster@nscc.ca

825 5475



The North Mountain is comprised of three volcanic flow units and was erupted from fissure volcanoes during the Triassic period, 200 Million Years ago. The three volcanic flow units are quite distinct and have variable resistance to erosion. As a result the morphology (shape) of the North Mountain reflects these differences in erodability of the flow units. The lower flow unit (oldest) is exposed along the south face of the North M Mountain and is quite thick, massive with columnar joints and very resistant to erosion. The resistance to erosion of this unit is in part why we have such a steep slope on the north side. The lower flow unit is overlaid by the Middle Flow unit which is comprised of several thin volcanic flows that are highly vesicular (gas bubbles). These air bubbles have been subsequently in filled with zeolite minerals as a result of ground water circulation through the rocks. Stilbite, Nova Scotia’s mineral, is one such mineral that infill’s these voids in the rocks. Zeolites have a unique crystal structure and grow radially outward. The Middle Flow unit is less resistant to erosion and is often referred to as “rotten rock” by local construction operators. The Upper Flow unit overlies the Middle Flow Units and is similar to the lower flow unit in that it is resistant to erosion and often outcrops along the Bay of Fundy Coast.



The flow units have been mapped with the aid of a new remote sensing technique known as LiDAR, Light Detection & Ranging. We use a laser onboard an aircraft to precisely measure the earth’s topography (lay of the land) to an accuracy of 15 cm in the vertical. The measurements are then used to construct a continuous surface known as a Digital Elevation Model (DEM). We then use these DEM in the computer to better visualize the subtle topographic changes of the land surface. As a result we can see the contacts between the flow units and other interesting landforms including raised terraces along the Bay of Fundy that represent higher sea-levels. After deglaciation 12-15,000 years ago, the sea-level rose faster than the earth’s crust rebounded. Evident of this high sea level is found at several locations along the coast in the form of terraces. Recent tide gauge records from Saint John, NB indicate relative sea-level is rising by 22 cm per century. This is a combination of crustal subsidence and global sea-level rise. We have also used these new LiDAR elevation models to map the town of Annapolis Royal and project possible flood limits based on storm surges and future projections of higher sea-levels. The Groundhog Day storm of 1976 was used a bench mark storm and the flood extent was mapped using the LiDAR DEM. Future sea-level rise projections were then used with this storm to predict what areas are at risk if the storm were to reoccur in the future.



The field trip will begin with a presentation of the sea-level history of the area, followed by an explanation of LiDAR and the improvements to topographic mapping that it provides. Flood maps of Annapolis Royal during the Groundhog Day storm and possible future flooding considering sea-level rise will be shown. Maps of the North Mountain will be displayed and the contact between the flow units identified. In addition we will examine these raised beach terraces that have resulted from past higher sea-levels. We will then depart to visit the different volcanic flow units and contacts in the field and the raised terraces along the coast.


Tim Webster, Ph.D.
Research Scientist, Applied Geomatics Research Group (AGRG)
Centre of Geographic Sciences (COGS), Nova Scotia Community College



Chair, Halifax Branch, Canadian Institute of Geomatics

Adjunct professor, Acadia University, Dept. of Earth and Environmental Sciences

Adjunct professor, Dalhousie University, Dept. of Earth Sciences