Consulting-Specifying Engineer - April 2008 - (Page 12) M/E Roundtable PARTICIPANTS Power grid problems This month’s panel discusses the national grid, its problem and innovations, and how to prepare for the digital future. BY MELISSA HILLEBRAND, Associate Editor CSE: Is there a general consensus that the national grid is unreliable and in need of overhaul? DAVID PERKINS: There are definitely signs the national electric grid is seeing strain that may lead to reduced reliability. Historically, grid reliability has been addressed by providing generating capacity margin in excess of anticipated peak demand. The Electric Reliability Council of Texas has published information showing capacity could fall below prescribed target margins of 12.5% by 2009. Elsewhere, the ability to bring additional generation capacity online has been hampered by environmental concerns. While coal has historically been the least expensive fuel for large-scale base power production, it also contributes the most to greenhouse gas emissions. Resource Media (2008) published a report showing more than two dozen coal-fired plant proposals were upended in 2007—the result of strong public opposition and uncertainty over the cost of complying with future carbon caps and emissions policies. Paul Joskow (2006) suggests that competitive wholesale electricity markets no longer provide financial incentive for the investment in peaking power plants that have high capital costs, low utilization rates, and uncertain demand requirements. Where free-market practices have led to capacity shortages, utilities and distribution companies have been forced to contract for additional capacity by mandate. CAREY COOK: The need for overhaul is driven by the fact that the grid will be used in different ways in the future. In the past, there were several regional grids around the country that, to different degrees, could be connected together to permit power flow, at least to adjacent grid sections. But, if there was a problem in one grid section, it could be quickly isolated from the other sections to minimize the extent of the problem. I don’t believe it was ever intended that electricity could be generated in, say, Florida and shipped to Washington state. But that seems to be the vision today, and it is in this context that the grid needs to be modernized. Quite apart from the fact that one state might have to live with the social costs of having the generating plant located therein, while a far-away state benefits from the electricity, there are other technical issues to address. For example, a regional grid section might choose to load their transmission lines conservatively, only to be told by national regulators that they must transmit power from Florida to Washington state, and never mind the fact that the transmission lines might be overloaded. To achieve a true national grid that will operate optimally, the existing regional grids will have to be updated to accommodate higher capacity levels. It will also be necessary to upgrade the interties between grid sections to increase power transfers and to improve protection and control equipment. CSE: Is the electrical grid keeping up with the digital economy? It would appear that the digital economy requires a level of power quality and reliability that the grid cannot deliver. PERKINS: It would be cost prohibitive for utilities to invest in infrastructure requirements needed to ensure near 100% system availability required Carey Cook Senior Strategic Marketing Manager S&C Electric Company Chicago David Perkins Chief Technical Officer Active Power Austin, Texas Additional reading • Electric Reliability Council of Texas, www.ercot.com • Energy Information Assn., www.eia.doe.gov • North American Reliability Corp., www.nerc.com • Edison Electric Institute, www.eei.org • Resource Media fact sheet: “$45.3 Billion In US CoalFired Power Plants Cancelled in 2007: Rising Costs Force Energy Firms to Ditch Plans for 31 New Plants,” www .scribacrc.org • Joskow, Paul. (2006). “Competitive Electricity Markets and Investment in New Generating Capacity,” Center for Energy and Environmental Policy Research, MIT. 12 Consulting-Specifying Engineer • APRIL 2008 http://www.ercot.com http://www.eia.doe.gov http://www.nerc.com http://www.eei.org http://www.scribacrc.org http://www.scribacrc.org
For optimal viewing of this digital publication, please enable JavaScript and then refresh the page. If you would like to try to load the digital publication without using Flash Player detection, please click here.