Charlie Salamone

1
Wind Generator Basics

• Charlie Salamone
• Cape Power Systems Consulting
• Presented at the Northeast Sustainable Energy
  Associations Wind Project Development Strategies
  for New England Workshop
• 3/7/06

2
Introduction

• Physical interconnection guide
• Typical wind unit and utility characteristics
• Informal utility meeting
• Information to ask about
• Do your homework
• Energy Balance Analysis

3
Physical Interconnection Guide
Typical transmission voltages range from 115 kV
to 345 kV
Large plants must interconnect to the
transmission grid (generally 20 MW or larger)
Typical distribution voltages range from 69 kV
to 4 kV
Small units (less than 20 MW) can connect to the
distribution system through a step up transformer
or (for much smaller units) through a customer
service connection
Typical supply voltages range from 480 v to 120 v
4
Physical Interconnection Guide

• Output ranges
• Many units available on the market with outputs
  ranging from 100 watts to 3.6 MW
• Output voltages range from 12 volts dc (battery
  charging units) to 480 volts ac
• Units with output voltages of 240 volts ac are
  usually best for customer service connections
• Typical interconnection
• components

5
Informal Utility Meeting

• NOT required but can be helpful
• Conducted before any formal meetings or studies
  are performed
• Will provide an overview of the process and
  economics involved
• What to ask
• Interconnection requirements and procedure
  description
• Type of supply being provided (I.e. voltage,
  transformer size, shared or single customer
  connection)
• Availability of hourly use data in electronic
  format
• Electrical facilities in close proximity to
  facility
• Rates and tariffs applicable to generators
  (particularly stand-by rate information)
• Options for utility to purchase excess power
• Options for sale of excess power into market
  system

6
Informal Utility Meeting

• What to expect
• Specific information concerning the process and
  your service
• General information concerning timeframes and
  interconnection costs
• Very general information concerning near by
  facilities and their capacities

7
Informal Utility Meeting

• What not to expect
• Dont expect any information to be binding or
  guaranteed
• Dont expect any specifics concerning viability
  of an interconnection point or associated costs
• Dont expect any advice or recommendations
  concerning excess energy sales
• Dont expect any information that would require
  studies or analysis
• Dont expect any recommendations concerning unit
  sizes, designs or construction requirements

8
Do Your Homework

• Energy use versus energy output might be a simple
  calculation if you lived in Aruba
• Wind blows between 10 and 15 mph 24 hrs/day
  almost all year long
• A 600 kw wind turbine could expect to produce
  3,942 mwh annually (500x8760x.90) and reduce
  demands by at least 500 kw.
• US sited units arent quite so easy

9
Energy Balance Analysis

• Analysis that estimates energy costs and savings
  for a prior year based on actual customer use
  data and publicly available wind data along
  with a bunch of assumptions.
• Customer use data
• Use data is usually available from utility on an
  hourly basis for an entire year in spreadsheet
  format
• Some data manipulation is required to format data
  into a monthly billing quantity compatible layout
• Billing rates and monthly billing cycle dates are
  also needed

10
Energy Balance Analysis

• Typical customer load profile data

11
Energy Balance Analysis

• Publicly available wind data
• Does not replace the need for site specific
  meteorological data
• May be used as a very general proxy for required
  data prior to more in-depth analysis
• Public sites where information on wind generation
  can be found
• http//seaboard.ndbc.noaa.gov/Maps/northeast_hist.
  shtml
• http//cdo.ncdc.noaa.gov/ulcd/ULCD
• http//www.uwig.org/
• http//www.awea.org/faq/index.html
• http//www.ibew.org/articles/05journal/0509/p14_wi
  ndmill.htm

12
Energy Balance Analysis

• Wind power generation calculation is highly
  complex but some simplifications can be made
• Translation of wind data into energy output will
  be required (this is the toughest part)
• Once data has been converted it can be merged
  with use data to derive an approximation of
• Energy use reduction and avoided energy costs
• Demand reduction and avoided demand charges
• Excess energy production and sales value

13
Example Wind Data Results
14
Energy Balance Analysis

• Results can provide a high level estimate of
  economic benefits versus costs of wind unit
  installation for your use characteristics
• Will only provide an indication of whether a more
  detailed analysis is worth the time and expense

15
Results of Analysis