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Electricity Policy and Market Context Electricity supply and use in local communities are shaped largely by two events that occurred in 1997. The Electric Utility Restructuring Act was passed to deregulate the electricity industry in Massachusetts, with the intent being to reduce rates and broaden choice for consumers. In addition, the New England electricity marketplace was created, under the administration of an entity known as ISO New England, to support the deregulation of the industry throughout the six-state region. Click on the links below for additional information.
Massachusetts Electric Utility Restructuring Act New England Electricity Marketplace Market & Grid Operations: Contract Path &Physical Path:;
Massachusetts Electric Utility Restructuring Act
Four key types of organizations now exist to provide energy services to Cape & Islands and other consumers in the restructured marketplace:
Industry restructuring was intended to create a robust market in which multiple suppliers would compete to serve consumers. To date, however, large industrial and commercial consumers have realized most of the economic benefits of competition, with residential consumers typically having little or no choice among suppliers. Several other important provisions of the 1997 act are summarized below:
New England Electricity Marketplace
The New England grid serves a population of more than 14 million people. It includes more than 8,000 miles of high-voltage, higher-efficiency transmission lines and many times more miles of lower-voltage distribution lines. It also includes high-voltage interconnections with systems in the state of New York and the provinces of Quebec and New Brunswick. The grid connects more than 6.5 million consumers to several hundred power plants and other generating facilities. In 2003, natural gas-, oil-, and coal-fired plants supplied almost 60% of the regions electricity, while nuclear plants accounted for more than 25%. Hydroelectric facilities and power plants burning wood and/or trash generated most of the remaining 15%. Wind, solar, and other renewable resources provided an almost negligible fraction of total electricity generation. (For more recent information from ISO-NE on trends in generation, click here.) ISO-NEs main control center in Holyoke, Mass., provides real-time direction on the electrical output of more than 350 generating sources and on the flow of power over the transmission system. ISO-NE also coordinates grid planning and administers wholesale power markets. These set the price of electricity by matching the amount supplied by generating facilities to the amount demanded by consumers. (For information on how markets work from ISO-NE, click here).
Real-time control is required because electricity is a unique commodity;it generally cannot be stored economically using present-day technology. ISO-NEs main control center, along with four satellite control centers managed by distribution companies, is responsible for instantaneously and continuously balancing supply and demand throughout New England based on the wholesale price of electricity. (See Market & Grid Operations: Contract Path & Physical Path for more information.) Wholesale electricity was priced uniformly throughout the region until March 1, 2003, when ISO-NE instituted a system known as locational marginal pricing (LMP). Eight different LMP zones exist, three in Massachusetts and one each in Connecticut, Maine, New Hampshire, Rhode Island, and Vermont. Cape Cod, Marthas Vineyard, and Nantucket are within the southeastern Massachusetts zone (SEMA). LMP provides clearer signals to market participants by more accurately reflecting the costs of wholesale power in different zones. In areas where prices are higher, clearer economic incentives exist for efforts to reduce electricity demand and to invest in new power supply and delivery capacity. (See Locational Marginal Pricing, a fact sheet from ISO-NE.)
Market & Grid Operations: Contract Path & Physical
Path
These distinctions are best understood by analogy: Imagine that the New England power grid represents a big tube and electrons represent water. Water flows into and out of the tube at equivalent rates because electricity cannot be stored. This rate continuously varies, reflecting fluctuations in total supply and demand throughout the region. Generating facilities pour water into the top of the tube, and consumers withdraw water from the bottom of the tube. Water takes the easiest route possible through the tube because electricity flows according to the laws of physics, taking the path of least resistance. On the contract path, each generator dumps a quantity of water into the tube based on the price agreements it has established with market participants located anywhere in New England. Wholesale and retail consumers covered by these agreements simultaneously remove water from the tube. The amount contributed by a generator at a certain price is balanced by the total amount withdrawn by its consumers at this price. On the physical path, all generators pour water into the tube through their transmission interconnections, and all consumers withdraw water through their local distribution networks. The water withdrawn by individual consumers may come from the nearest generator, or it may come from one located some distance away, depending on the easiest pathway through the tube. In the Cape & Islands region, NStar and National Grid (National Electric) have traditionally determined the contract path for the majority of consumers. These organizations may be buying electricity generated locally, elsewhere in New England, or in New York, Quebec, or New Brunswick. In 2005, the contract path for most consumers on Cape Cod and Martha's Vineyard began to be defined by the Cape Light Compact under its competitive power supply agreement with ConEdison Solutions. In many areas of New England, the power grid is too complex to isolate the physical path of the electricity delivered to individual consumers. But Cape Cod, Marthas Vineyard, and Nantucket have a much simpler grid: When the Canal Power Plant in Sandwich, one of the dirtiest facilities in Massachusetts, is operating, it generates the power consumed in local communities. When it is not operating, the nearest sources generally supply the power imported over tranmission lines crossing the canal and connecting the islands to the mainland: Brayton Point, the dirtiest plant in New England, and Pilgrim, the only nuclear plant in the state. Last updated 09.10.07. |
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