MA Utility Distribution Planning Process

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MA Utility Distribution Planning Process

• Fitchburg Gas and Electric Light Co
• Massachusetts Electric Co
• NSTAR Electric
• Western Massachusetts Electric Co
• December 10, 2004
• MA DG Collaborative

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Utility Panel

• Bob Galgano Manager of Distribution Planning
  and Engineering MECo
• Cindy Janke Senior Engineer WMECO
• Paul Krell Senior Distribution Engineer FGE
• Charlie Salamone Director of System Planning -
  NSTAR

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Agenda

• Review of Utility Obligation to Serve
• Overview of Planning Process
• Load Forecasting
• Capacity Planning
• System Design
• Other Distribution Planning Drivers
• Planning Schedules
• Planning Assumptions about DG
• Directions for Future Discussion

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Obligation to Serve

• Distribution companies are expected to be capable
  of serving the distribution load under all
  reasonably expected load conditions
• Now and in the future
• Maintain high reliability
• Service quality standards provide penalties for
  not meeting reliability goals
• We must respond to all requests for new service

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Obligation to Serve

• Maintain safe conditions
• Protecting the public and utility workers from
  the inherent dangers of electricity distribution
• Provide proper voltages
• Strive to maintain delivered voltages at customer
  premises as per ANSI standard C84.1
• Voltage regulation needs constant attention due
  to the dynamic loads on the system

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Load Forecasting

• Need to forecast loads for each feeder and
  substation for seasonal peaks over 10 year
  horizon
• MECo 1,115 feeders, 295 substations
• NSTAR 1,300 feeders, 300 substations
• WMECo 271 feeders 43 substations
• FGE 44 feeders 17 substations
• Total 2,730 feeders 655 substations
• Forecasting occurs annually for all this
  equipment in many cases requires analysis for
  both summer and winter seasons

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Load Forecasting

• Forecast process includes system-wide review
• Econometric and historical trend - based load
  growth
• Weather sensitivities summer and winter peaks
• Must review to determine accurate forecast
• Must account for above or below average
  historical weather data
• MA economic data used
• In-state varying geographic forecasts are used as
  well
• Other things that affect these forecasts
• Land prices
• Local zoning changes
• New transit infrastructure (i.e. roads,
  railroads, etc.)

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Load Forecasting

• Forecast process includes local review
• Gradual load growth over time
• Weather sensitive load growth
• 89 air conditioners
• Large loads coming in (new mall, large housing
  developments, etc.)
• Large loads leaving (relocation, bankruptcies,
  etc.)
• Need to account for unusual individual customer
  load variability
• Use both computerized modeling as well as direct
  customer information
• Use of system loading information

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Load Characteristics Illustrative Mid Week Day
Summer Peak Load Cycle Residential Feeder
Summer Peak Load Cycle C/I Feeder
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Capacity Planning

• Addresses how to meet projected load for each
  distribution feeder
• Considers both near term and long term needs
• Need to be responsive to
• Customer expectations for service
• Equipment/construction lead time
• Feeder lead times 6 months to 2 years
• Substation lead times 2 to 5 years

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Capacity Planning

• Capacity improvements serve multiple objectives
• Customer demands
• Feeder back-up
• Substation back-up
• Long term availability essential to design
• Ease of switching
• How is voltage regulated in different
  configurations?

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Capacity Planning

• Primary purpose is to serve projected peak
  customer loads
• Secondary purpose is to satisfy foreseeable
  equipment outage conditions, i.e. with a backup
  source
• Emergency switching requirements for main line
  feeders
• Numerous switching and reconfiguration options
  employed
• Can not overload or damage existing
  infrastructure
• Many elements serve multiple roles in supporting
  system
• Airbreak switches
• Capacitor banks
• Reclosers, etc.

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Typical Distribution System Design
Load Transfer Switches
Substations
Distribution circuits use multiple tie points
from multiple stations to provide load transfer
capabilities and backup capacity
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Typical Distribution System Design

• Need to design in flexibility
• Need to be able to maintain and operate system
  under all conditions
• Inclement weather is not an excuse for something
  not operating
• Need to maintain proper voltages even under
  emergency switching conditions
• Needs to be user-friendly for dispatchers to be
  able to quickly respond to emergencies

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Other Distribution Planning Drivers

• Reliability of feeders and substations is a
  priority
• Number of outages in area
• Tree protection
• Underground cabling construction
• Animal proofing equipment
• Flexibility of field switching points
• Need to accommodate critical facilities
  (hospitals, nursing homes, etc.)
• Its always the distribution companys fault when
  there is an outage

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Other Distribution Planning Drivers

• Asset Replacement
• Investments where existing assets are at the end
  of their operational life
• Age of equipment (includes legacy systems)
• Timing driven more by scale and physical
  condition than performance
• Performance can still be good, but spare parts
  are difficult to locate
• Power Quality considerations

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Other Distribution Planning Drivers

• Distribution companies spend varying amounts of
  their capital budgets on capital improvement
  projects
• Asset Replacement 25-35 of the total budget
• Reliability 25-35
• Capacity 30-50
• In many cases capacity projects fit more than one
  category
• Reflects actions necessary to satisfy obligation
  to serve and achieve quality of service

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Other Distribution Planning Drivers

• Under deregulation, no vertically integrated
  planning
• Each entity in MA plans for its customers needs
• Distribution Regulated distribution companies
  plan for use of distribution system only
• Transmission FERC regulated transmission
  companies plan for transmission improvements
  needed by system
• Generation
• Unregulated generators produce and sell power
• Distribution companies do not plan for energy
  production or generation requirements

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Other Distribution Planning Drivers

• Non restructured parts of the country
• Utility may be involved with planning on all
  aspects of the system distribution,
  transmission, and generation
• This can lead to much higher capital expenditures
  for those utilities
• If utility is at risk for high supply pricing, it
  may install DG for its needs not as a TD
  alternative, but simply to prevent buying high
  priced supply for a few hours per year

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Planning Schedules

• Most areas are now summer peaking
• Review peak loading in the late fall
• Determine where shortfalls exist
• Continuous process
• Compare to prior forecasts for area
• Were temperatures below average last summer?
• How will this affect forecasts?
• Look at 1 - 10 year horizons
• Review older historical forecasts for accuracy
• Make adjustments as necessary

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Planning Schedules

• Implementation timeline
• Site permitting
• Procurement
• Construction
• Must be complete in time to meet projected need
• Forecasts are high quality engineering
  predictions
• Distribution companies do not have a crystal ball

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Planning Assumptions about DG

• Customer decides when to operate DG, not
  distribution company
• Maintenance of DG
• Failure of DG
• DG shutdown
• Fuel arbitrage
• Contractual disputes
• No obligation to serve load
• Environmental permitting issues
• Customer expects distribution company to serve
  its load whenever DG is unavailable

Customer-owned
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Planning Assumptions about DG

• Distribution company must plan for worst case
• Could affect neighboring customers if DG trips
  off-line and planning assumed it would be
  available
• Limited diversity of large units
• Few, if any, customers have multiple units in
  place
• Few, if any, multiple customers with DG on same
  feeder or in same area
• Distribution companies do not presently rely on
  customer-owned DG for system planning

Customer-owned
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Directions for Future Discussion

• Requirements for the use of customer owned DG in
  distribution planning include but are not limited
  to
• Availability of units
• Remote control/dispatch capabilities
• Real-time information
• Emergency condition operation
• Fuel supply / fuel storage
• Maintenance schedules
• Distribution companies need to better understand
  strengths and weaknesses of various DG
  technologies

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Directions for Future Discussion

• Informational needs
• Standardized specifications for typical DG
• DG ride-through system capabilities
• Power Quality considerations
• Contractual issues
• Specific operating parameters
• Liquidated damages provision for sub-standard
  performance
• Bonding required to assure DG is still in place
  if there is a business ownership change or
  disruption
• Timeline constraints
• How quickly can DG be installed?

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Directions for Future Discussion

• Potential DG application scenarios
• Large area supply planning cases where
  distribution and/or substation supply concerns
  are expected (significant capital expenditure)
• Locations that have limited and predicable growth
  (sustained deferral value)
• Locations where multiple units can provide
  support for an area (dependable availability)
• Installations that are dispatchable by the
  distribution company (controllable response)
• Need for MWs, not kWs, of load relief
• Minimum is 1-2 MW need

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Directions for Future Discussion

• Value to distribution system
• Deferral value calculation
• What happens at end of deferral time?
• Value is no longer available once distribution
  system infrastructure is built
• How to treat lost revenue from DG operations
• Standby service costs
• Rate treatment of payments from distribution
  companies to DG owners
• Capital ?
• OM ?
• FERC accounting ?

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• Questions ?