Myths and Realities of Renewable Energy

by Meir Shargal and Doug Houseman

Capgemini

All over the world scientists are racing to create energy without damaging the earth. The so-called renewable energies use natural resources such as sunlight, wind, rain, tides, and geothermal heat, which are naturally replenished. The technologies range from Wind Power, Hydroelectricity, Wave, Solar, Biomass, and Biofuels.

Although most renewable energy sources do not produce pollution directly, critics point out that the materials, industrial processes, and construction equipment used to create them may generate waste and pollution, prove dangerous, take up large amounts of land, or be incapable of generating a large net amount of energy.

In light of the ever increasing investment in renewable energy technologies, it’s important to separate fact from fiction in this growing field. This article identifies a half dozen of the most common misconceptions.

Myth: Plug-in cars will reduce air pollution.

The expected introduction of plug-in hybrid electric vehicles could cut U.S. gasoline use but could increase deadly air pollution in some areas. That's because a plug-in hybrid electric vehicles lower tailpipe emissions may be offset by smokestack emissions from the utility generating plants supplying electricity to recharge the big batteries that allow plug-ins to run up to 40 miles without kicking on their gasoline engines.

About 49% of U.S. electricity is generated using coal, so in some regions a plug-in running on its batteries is nearly the equivalent of a coal-burning vehicle. The trade-off is one that even plug-in backers acknowledge. It could undercut the appeal of vehicles that appear capable of using no gasoline in town and hitting 50 to 100 mpg overall fuel economy. There is a possibility for significant increases of soot and mercury, if large numbers of plug-in hybrids were being recharged with power from the least-sophisticated coal plants.

The longer a plug-in is designed to operate on just the batteries, the less gasoline it uses, but the more electricity it needs to recharge the larger batteries. Thus, the better the Plug-in Hybrid car – that is, the longer it goes just on its batteries – the greater the charge required and the more the pollution that might result from an electric utility's power generation.

Myth: Current electric infrastructure can support the growth in plug-in cars.

U.S. government scientists have found the increasing use of plug-in hybrid electric cars and trucks might substantially affect power distribution. Oak Ridge National Laboratory (ORNL) researchers examined how an expected increase in ownership of hybrid electric cars and trucks will affect the nation's power grid depending on the time of day or night the vehicles are charged. In an analysis of the potential impacts of plug-in hybrid electric vehicles projected for 2020 and 2030 in 13 U.S. regions, ORNL researchers ran several scenarios for each region for the times of 5 p.m. or 10:00 p.m., in addition to other variables. The report found in the worst-case scenario – if all hybrid owners charged their vehicles at 5 p.m. at six kilowatts of power – 160 large power plants would be needed nationwide to supply the extra electricity, and the demand would reduce the reserve power margins for a particular region's system.

Myth: Transmission grid can support the transportation of renewable electricity generated in rural areas to homes and business that need it in large metropolitan areas.

The US wind-power boom, especially in rural parts of Texas, the Midwest, and California, is poised to outstrip the capacity of high-voltage lines to send the electricity hundreds of miles to population centers such as Dallas, Chicago, and Los Angeles. The transmission-line shortage is threatening to slow wind energy's breakneck growth and could prevent some states from meeting renewable energy mandates.

Wind power depends on a robust transmission grid. Wind farms are in remote reaches where gusts are strongest, while the greatest power demand is in cities. Until now, wind developers have piggybacked on existing wires, but after wind energy soared 45% last year, spare transmission capacity is depleted.

Wind developers won't go ahead with projects until transmission lines are in place, and utilities are loath to build the lines until they're sure the developers won't back out. Also, the first wind developer in an area is often asked to invest much of the $1.5 million-per-mile cost of a high-voltage line.

Texas, which has about 25% of U.S. wind power, saw eye-popping growth in 2008. Similarly, in southwest Minnesota, dozens of wind projects have been proposed to serve the Twin Cities. Even if just 30% of them, with 7,500 megawatts of capacity, are developed, that would far outpace the 2,000 megawatts of transmission capacity planned. Similar bottlenecks are stalling wind farms in the Midwest, Southwest and California.

Xcel Energy, a Midwest utility, says it can't raise money for transmission lines that might not carry any juice. "You're committing $1 billion in capital in the hope the cost recovery will come, and that's a tough proposition," says Paul Bonavia, head of Xcel's utilities group. To break the logjam, officials in Texas, the Southwest, Minnesota, and California plan to spread transmission-line costs among multiple wind developers or utilities. At the national level, Senate Majority Leader Harry Reid (D-Nev.) recently announced plans to introduce legislation that will give the federal government more authority over sitting and building transmission lines. But neither move will offer near-term relief. A wind farm can be built in 18 months, while a transmission line can take five to 10 years.

Myth: Wind energy provide security of electricity supply.

Operators of the Texas state power grid scrambled in spring 2008 to keep the lights on after a sudden drop in West Texas wind threatened to cause rolling blackouts. A sudden uptick in electricity use coupled with other factors and a sudden drop in wind power caused the unexpected dip. As a result, grid officials immediately went to the second stage of its emergency blackout prevention plan. The drop in wind power led to constraints on the system between the north part of the state and the west.

Some critics have said that wind power, although providing a source of clean energy, also brings with it plenty of hidden costs and technical challenges. Besides requiring the construction of expensive transmission lines, the fickle nature of wind also means that the state cannot depend on the turbines to replace other sorts of generators. Renewable energy is not the sole answer to Texas power needs; Texas can't put all the eggs in one basket when it comes to any form of generation, we need to consider the cost and the reliability issues, in addition to the environmental impact.

Myth: Most renewable sources are intermittent and cannot be relied on to secure our energy supply.

A variety of renewable sources in combination can overcome this problem. Stormy weather, bad for direct solar collection, is generally good for windmills and small hydropower plants; dry, sunny weather, bad for hydropower, is ideal for photovoltaics.

The challenge of variable power supply may be further alleviated by energy storage. Available storage options include pumped-storage hydro systems, batteries, hydrogen fuel cells, and thermal mass. Initial investments in such energy storage systems can be high, although the costs can be recovered over the life of the system.

Wave energy is continuously available, although wave intensity varies by season. A wave energy scheme installed in Australia generates electricity with an 80% availability factor.

Myth: Greater efficiency results in lower energy consumption and, therefore, will hasten the day of energy independence.

History shows that as the U.S. economy has grown more energy efficient, energy consumption has continued to climb. In 1980, the U.S. was using about 15,000 Btu per dollar of Gross Domestic Product (GDP). By 2004, the energy intensity of the U.S. economy had improved dramatically, so that just over 9000 Btu were required for each dollar of GDP. By 2030, the US Department of Energy (DOE) Energy Information Administration (EIA) projects that energy intensity will fall to about 5800 Btu per dollar of GDP. But even with that dramatic increase in efficiency, the EIA predicts that overall energy consumption in the U.S. will increase by more than 30 percent, rising from 100.1 quadrillion Btu in 2005 to 131.1 quadrillion Btu in 2030. (A quadrillion Btu is equal to about 172 million barrels of crude oil.)

Conclusion

Renewable energy sources are only one part one side of the equation. Finding more efficient ways to generate electricity is just as important.  Indeed, improving energy efficiency represents the most immediate and often the most cost-effective way to reduce oil dependence, improve energy security, and reduce the health and environmental impact of the energy system. By reducing the total energy requirements of the economy, improved energy efficiency could make increased reliance on renewable energy sources more practical and affordable.

The consensus among scientists is that the best way to address climate change is to (1) first find ways to reduce our consumption; (2) create a smarter grid that will minimize the electricity losses, and (3) finally find technological solutions that will supply endless energy. Until that endless source of energy is found, we need to spread the message of balancing renewable with efficiency and reduced consumption.

Adapted from another version with permission from the authors.

Meir Shargal is a Principal with Capgemini Global Utility practice focusing on Smart Grid strategy and transformation. He is a strong, analytical leader who combines innovation with pragmatism, and vision with execution and a sense of urgency. With more than 20 years experience in strategy, transformation, and enterprise architecture, Meir is multifaceted technologist/strategist with proven experience in the alignment of technology solutions with business goals. He Holds BS in computer science and MS in Management Information Systems

Doug Houseman is CTO for Capgemini’s Global Energy, Utilities and Chemicals. He has more than 30 years of worldwide utility experience in all aspects of the utility and energy industry from engineering and design to maintenance and production. He has been selected as the lead investigator for a 20-year industry roadmap by one of the largest trade associations. Major companies in the industry and solution providers have turned to him to define innovative solutions to new complex problems. Doug has spoken at over 200 events, including international conferences. He holds a BS degree from the US Naval Academy and is a registered Professional Engineer (PE).

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