REPORT SAYS WIRES WILL BE READY FOR NEW ENERGY

For the Electric Grid, Renewable Goals Pose Daunting Task
Peter Behr, April 16, 2009 (NY Times)

SUMMARY
Accomodating High Levels of Variable Generation, from the North American Electric Reliability Corp. (NERC), says building the New Energy Superhighway will be difficult but it can and must be done.

The U.S. electric transmission system is old and inefficient. This poses significant challenges for grid operators charged with integrating New Energy into U.S. power generation. It could be the limiting factor in New Energy use.

In the same way that more efficient, high capacity wires have been developed as the need to carry more power more efficiently grew, the NERC report finds the technology necessary to integrate and manage New Energy in a national transmission system must and will soon emerge.

The NERC study is intended to inform the debate in Congress beginning this week on proposed legislation to up U.S. use of New Energy and to fund a New Energy Superhighway.

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The U.S. presently gets ~1.9% of its power from New Energy sources. A proposed national Renewable Electricity Standard (RES) now before the Senate Energy and Natural Resources Committee bill would require the nation’s utilities to obtain 20% of their power from New Energy sources by 2021, progressively expanding from a 4% standard in 2012. A House RES, now before the Energy and Commerce Committee, would require 25% by 2025, starting with 6% in 2012.

Although the bills provide for meeting a part of the requirements with Energy Efficiencies that lower power consumption, they would inevitably add a lot of New Energy into the power mix on the grid. The Joint Coordinated System Plan, a grid operators’ study, concluded that a 20%-by-2024 requirement would necessarily add 229,000 megawatts of wind energy on transmission systems east of the Rocky Mountains.

This constitutes a “fundamental change” for grid operators. The NERC plan is an outline for how to make this change.

The controversy among experts is over how fast the change can be made without endangering the delivery of power to U.S. ratepayers.

The transition is scheduled over more than a decade. Research and monitoring are ongoing. NERC and its report urge that they remain a high priority.

Distributed generation, storage and technological advances will also contribute to New Energy use.

NERC has some concern that planners and legislators not be too quick to eliminate sources of traditional power generation but wait until it is clear the transmission system is ready.

At the same time, new regulatory schemes and market plans must be developed.

Forecasting is already accurate and will get better. (click to enlarge)

COMMENTARY
The 3 basic NERC objectives: (1) Consider the impacts of variable generation in system planning and design and develop practices and methods to maintain long-term reliability; (2) Develop the new tools, practices and standards to maintain system reliability; (3) Write a reference manual for planners and operators which describes the changes required to accommodate variable generation.

The reason the U.S. transmission system is so completely inadequate is that it was created for the delivery of local and regional energy to local and regional consumers while New Energy must be delivered from resource-rich remote locations to high-demand population centers all around the country.

There is a whole new level of weather forecasting and resource mapping available to grid operators that dramatically reduces the impact of the New Energies’ intermitency. Between computer models and onsite power flow monitors, the ability of grid operators to know how much and where New Energy supplies are is already so great as to make failures at least no more likely and perhaps less likely than failures from traditional sources of power to the grid like coal or nuclear energy.

Integration 1: Wind power drops off during the day and rises at night...(click to enlarge)

Opponents of New Energy cite the 2008 incident in Texas - when a sudden, unanticipated fall in wind threatened the electricity supply - as an example of the dangers of depending on intermittent New Energies. The fact of the matter is that grid operators were able to respond without any inconvenience to power consumers. During the same week, a potentially catastrophic failure at a nuclear plant in Florida took massive amounts of power offline and left utility customers in sweltering darkness for hours.

Discussions of smoothing the grid impacts of New Energy intermittency invariably come to the topic of improved energy storage. Development of Compressed Alternative Energy Storage (CAES) technology continues to move forward but it remains costly and unproven. The low tech flywheel big enough to provide high volume storage for wind and solar power plants is still the just-barely-unreachable dream, not unlike price-competitive mega-batteries. Vehicle-to-grid (V2G) technology incorporating big numbers of battery electric vehicles (BEVs) may be the soonest-to-arrive source of large-scale storage for New Energy.

Integration 2: Solar power rises during the day and falls off at night...(click to enlarge)

Advances in forecasting, real time information and transmission system smart technology will likely make the use of intermittent sources progressively more practical whether advances in storage technologies emerge or not.

Distributed generation (rooftop solar, small wind, home geothermal) is one method of using New Energy without adding stress to the transmission system.

Enhanced technologies like modern wind turbines that adjust to weather conditions and solar power plants with short-term storage capacities will also ease the complexity of integrating New Energy into a national transmission system.

Integration 3: A good system uses what's available. (click to enlarge)

QUOTES
- Denise Bode, CEO, American Wind Energy Association (AWEA): "[The NERC report is] an excellent road map for the grid planning and operations changes needed for America's future electric generation portfolio."
- Revis James, director of energy technology assessment, Electric Power Research Institute (EPRI): "How much renewable energy can you have before [you] have to have systemic improvements to the system to handle the variability of renewables?…Is 10 percent too high? No one knows what the magic number is…Are we moving too fast? On the policymakers' side, there's a lot that is not still understood about the implications of a large share of renewables."

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- NERC report: “The amount of variable renewable generation is expected to grow considerably as policy and regulations on greenhouse gas emissions are being developed and implemented by individual states and provinces throughout the North America. This proposed level of commitment to renewable variable generation offers many benefits such as new energy resources, fuel diversification, and greenhouse gas and particulates reductions…As this major shift in resource implementation is underway, it is imperative that power system planners and operators understand the potential reliability impacts associated with large scale integration of variable generation. They also need to develop the planning and operational practices, methods and resources needed to reliably integrate variable generation resources into the bulk power system.”