Maine Public Utilities Commission

MEDIA ADVISORY

Maine Public Utilities Commission
242 State Street
Augusta, Maine 04333-0018
Website: http://www.maine.gov/mpuc/, E-mail: maine.puc@maine.gov
CONTACT: Phillip Lindley, 207.287.1598, phil.lindley@maine.gov

 

FOR IMMEDIATE RELEASE
July 2, 2004 

Maine PUC: Summer Power Alert Procedures  

AUGUSTA, MAINE – Consumers’ demand for electric power peaks during the summer season in New England, due primarily to air conditioning loads.  In past years, the regional bulk power grids that provide electric power to Maine consumers have experienced supply capacity deficiencies during the summer months, but supplies appear to be sufficient to meet anticipated demands this summer.  Even when regional demand is very high, Maine is in a better position than many other parts of the northeast region, because Maine has ample generation capacity for our needs, selling the excess out of state. 

Most Maine consumers are connected to the New England Power Pool (NEPOOL) bulk power supply system operated by the Independent System Operator New England, Inc. (ISO-NE) in Holyoke, Massachusetts.  Some Maine consumers in northern and easternmost Maine are connected to the Maritimes system operated by New Brunswick Power in Fredericton, New Brunswick.  Both systems expect their capacity situations to be positive this summer. 

ISO-NE has forecast a peak load for the region (most of Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, and most of Connecticut) of 25,735 MW during summer 2004; we could encounter that peak at any time during the summer season (June through August).  The generally available generation capacity within the region is over 30,000 MW, and New England can import an additional 2,000 MW from Canada if needed.  In Maine, peak summer loads of approximately 1,900 MW are expected, with about 3,500 MW of generation capacity available within the State’s borders to meet that load.  Maine exports the excess power through New Hampshire to assist consumers in the rest of the New England.

The ISO-NE communicates regularly with power generators, brokers, electric distribution companies, and state and federal government officials on the stability of the regional power supply.  If, for any reason, supply were not expected to meet demand, the ISO-NE would take a number of steps to maintain the reliability of the regional power grid.  If the required safety margin (generation over demand) begins to shrink, ISO-NE would advise generators and utilities to curtail unnecessary maintenance – service to consumers would not initially be affected.  If the region slips below the desired reserve levels, ISO-NE would implement capacity deficiency “Operating Procedure 4,” or OP4.[1] 

The first action under OP4 is an internal Power Caution advisory to government agencies and generators.  The next series of actions asks blocks of large customers who have “interruptible” contracts to curtail their loads.  If the interruptibles and purchases of power from outside the region are not sufficient to meet anticipated demand for the day, ISO-NE would declare a POWER WATCH, notifying the public, media and government agencies of a supply deficiency and encouraging customers to voluntarily reduce electricity usage.  A five percent voltage reduction could also be implemented as a temporary remedy; other than for customers with highly sensitive motors or other electrical equipment, such a voltage reduction would be imperceptible. 

In extraordinary circumstances when there is a more urgent need for voluntary load reduction measures to maintain grid reliability, ISO-NE could declare a POWER WARNING, asking the media to use radio and TV to appeal for the public to voluntarily curtail load as soon as possible.  Under emergency circumstances, the ISO-NE may ask state governors to reinforce the broadcast appeals for load curtailment.

OP4 relief measures have always been sufficient to balance load and generation within New England during capacity deficiencies.  If, however, major generating stations or transmission lines fail when the regional grid is operating in a highly stressed condition in advanced OP4 stages, ISO-NE could declare a SYSTEM EMERGENCY and implement Operating Procedure 7 (OP7).  Utilities would be directed to cut power to some consumers, by implementing non-voluntary rotating feeders (“rolling blackouts”) to blocks of consumers – the number and location depending on the size and nature of the power deficiency.  Each block could be without power for a number of hours without prior public notice.  New England is the only area of the country that has never imposed SYSTEM EMERGENCY rolling blackouts. 

In the event that extreme problems were to develop that disabled the regional bulk power supply system in our area, the OP4 and OP7 measures might not be sufficient to maintain our local power grids.  On August 14, 2003, such events occurred in the upper Midwest and New York, but the New England system remained largely intact as a result of the NEPOOL system’s design, communications, and ISO-NE operating procedures. Should local power grids be disabled as a result of such an extreme event, ISO-NE and local utilities would implement Operating Procedure 6 (OP6), a process to stabilize and bring the power grid system back to normal operation.  Power outage durations would depend on the time it would take to identify and isolate the problem, and a consumer’s location within the system.   

Maine is in a better position than other parts of the region.  It has more than enough generation capacity for its needs, selling the excess out of state.  Because the transmission lines connecting Maine’s generators to the rest of the region are usually filled to capacity, Maine would not likely have the same power problems as other parts of New England.  Rolling blackouts, for instance, would be implemented only where beneficial to the overall system. 

If a power shortage or emergency were to occur on the NEPOOL grid due to unforeseen circumstances, Maine government (including the Governor’s Office, Maine Emergency Management Agency, and the PUC) would receive alerts regarding the status of the electric system from the ISO-NE and CMP.  In addition, Maine utility companies (CMP, BHE, etc.) would be in direct contact with local media and their customers during SYSTEM EMERGENCY conditions.  Due to local circumstances this summer, ISO-NE could be faced with implementing OP4 measures in some areas of New England where the bulk power supply system may be less robust than in Maine.  In that event, ISO-NE media advisories would clearly state the areas affected by OP4 advisories, and those that would be exempt.  Media inquiries should first be directed to the ISO-NE (Ellen Foley) and the Maine PUC (complete contact information below).

#####

For more information:

Ellen Foley, ISO-NE, (413) 535-4139
For additional background information on this issue, contact Joe Sukaskas or Phil Lindley at the Maine PUC, 207-287-3831, maine.puc@maine.gov.