Treasure Valley Electrical Plan

Transcription

1 Treasure Valley Electrical Plan Community Advisory Committee January 25, 2006

2 Agenda 10 a.m. Welcome 10:10 a.m. Follow up DSM discussion 10:30 a.m. TVEP CAC process update 10:40 a.m. Transmission Presentation Overview & Reliability 11:40 a.m. Lunch 12:10 p.m. Small group discussion Transmission in the Treasure Valley 1:20 p.m. Confirm next steps 2

3 Recap of Previous Meetings August 24 Toured Facilities Fossil Gulch Wind Park Bennett Mountain Power Plant Boise Bench Substation (drive by) September 22 Toured Facilities (makeup session) Bennett Mountain Power Plant Caldwell Substation 3

4 Recap of Previous Meetings September 28 Overview of Idaho Power System Discussed base load vs peaking power plants Integrated Resource Plan Brief discussion of Treasure Valley power supply 4

5 Recap of Previous Meetings October 26 Discussed generation in the Treasure Valley Discussed Treasure Valley distribution buildout Breakout discussion about pros and cons of generation in Treasure Valley 5

6 Recap of Previous Meetings November 30 Regional Planning Updates Communities in Motion Blueprint for Good Growth Demand Side Management presentation Demand Side Management breakout sessions Barriers to DSM What would it take to exceed expected results? How could Idaho Power encourage community support of DSM? 6

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8 Future Treasure Valley Electrical Projections 2030 Buildout Population 873,561 2,400,000 Electrical Demand (MW) 2,620 7,200 DSM Potential (20-30% of new load) Total Planning Load

9 Population & Demand Projections Buildout population determined using 3 different methods. The first method was described in October Used land based GIS approach based on availability of land, proximity to transportation etc. Assigned 3 density zones Urban Suburban Rural 9

10 Population & Demand Projections The second method used zoning as determined by using comprehensive plans of the various cities. Some cities don t have comp plans. Made assumptions based on nearby cities For each zone, assigned a loading (kw) per square mile based on the type of zoning. Added up load for each zoning type. For areas outside of city areas of impact, assumed would all be 2 acre residential lots. 10

11 Population & Demand Projections The third method ignored everything other than residential zoning with the assumption that all residences will be in areas zoned residential. Assumed areas will fill in accordance with their zoning. I.e. R-4 will have 4 residences per acre, etc. Idaho Power estimates there are about 2.5 people per customer Subtracted out land for golf courses, parks, etc. All three methods result in between 7,000 and 7,200 MW of load. Population estimates for second two methods both near 2.4 million. 11

12 12 Substation Types

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14 Substation Types Source Substation Act as the receiving point for energy produced at distant generation. Typically 230 kv and higher Can be co-located with other types of substations Send out power at 230 kv to Hub Substations Currently there are 2 Source Substations in the Treasure Valley 14

15 Substation Types Hub Substations Convert 230 kv (typically) to 138 kv for transmission to Distribution Substations. Each Hub Substation can have 2 or more 138 kv loops fed from them 3 to 5 distribution substations per loop Currently there are 3 Hub Substations in the Treasure Valley 15

16 Substation Types Distribution Substation Convert the 138 kv transmission from the loops fed by the Hub Substations to 13.8 or 34.5 kv for delivery to its end use 16

17 Transmission Loop Configuration Three-Four 230 kv lines into the Hub Substation Two 138 kv loops (Four Lines) Three to Five Distribution Stations on a loop 138 kv 230 kv 17

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19 19 Treasure Valley 138kV Transmission Layout

20 Transmission

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22 Idaho Power Voltage Levels Extra-high voltage Transmission 230,000; 345,000; 500,000 volts Used for transmitting electrical energy over great distance. Higher voltage lines are more efficient than lower voltage lines. Higher voltage line results in fewer losses than a lower voltage line. Idaho Power loses between 2 and 3 percent of its energy due to line losses on the extrahigh voltage transmission system. 22

23 230 kv corner structure. Similar in diameter to 500 kv structure 23

24 230 kv transmission on Eagle Road Note the transmission line is in road rightof-way. 24

25 kv and 230 kv lines running down McMillan Road

26 Idaho Power Voltage Levels 138 kv 13.8 kv Underbuild Sub-transmission lines 69,000; 138,000; 161,000 volts Used for transmitting energy between substations that are close to one another Up to ~ 100 miles Will typically not carry as much energy as extra-high voltage lines. 26

27 Idaho Power Voltage Levels Distribution Lines 13,800; 34,500 volts Used for transmitting energy to its end use. Commercial facilities Small factories Small transformer outside a group of houses. 27

28 Transmission Line Capacity There are many factors that go into determining how much power a given transmission line can carry. For general purposes, we can say: 500 kv line can carry ~ 1,000 to 1,500 MW 345 kv line can carry ~ 700 to 1,000 MW 230 kv line can carry ~ 300 to 500 MW All the above lines will normally be operated in parallel (electrically alongside) with another line of equal size or a set of lower voltage lines. 28

29 Transmission Reliability Idaho Power must be able to reliably serve its customers under all normal operating conditions and under expected abnormal operating conditions (events that are statistically likely to occur fairly often) 29

30 Transmission Reliability Idaho Power voluntarily complies with WECC reliability standards. By agreement, WECC can impose financial penalties on Idaho Power for reliability violations Idaho Power must periodically submit reports to the WECC on varying reliability topics. IPUC has some oversight authority Can force Idaho Power to improve its system if reliability degrades enough. 30

31 Transmission Reliability Transmission system must be able to survive the single worst contingency (abnormal condition) on the system. No one event on a major transmission line can disrupt the system, making it unable to supply all the end users. Certain transmission lines are not loaded to their full capacity they hold some in reserve. Additional capacity is held in reserve so that energy can be imported from surrounding utilities should Idaho Power lose generation. 31

32 Transmission Reliability Idaho Power must also adhere to what s known as an n-1 criterion. For multiple transmission lines delivering power to the same point, if one of the lines goes out of service, the remaining lines must be able to carry both the load they were carrying before the event, plus the load carried by the line that is out of service. This is true even if the line with the highest capacity is the one that goes out of service. Only holds true for major transmission lines. 32

33 N-1 1 Animation

34 Transmission Reliability Not all transmission has backup Many times, a single lower voltage line will be the only transmission serving an area so that if the line goes out of service, the customers being served by that line lose power. Typical of smaller demand areas such as in mountains or rural areas. 34

35 Transmission Reliability Not everyone sees the same level of reliability. It would be prohibitively expensive to ensure all customers had the same reliability. Customers located in urban areas generally have the ability to receive power from more than one feeder. More remote customers have only one feeder serving their area. In mountainous areas, snow and wind will cause more outages. 35

36 Transmission Right of Way The width of right-of-way corridor required for a transmission line is set by the National Electrical Safety Code. Takes into account blowout How far the wire can be expected to swing during a high wind on a hot day. Can t come close to structures or trees because of wind. If a tower is made taller, sometimes it will require less ROW width. Single pole structures also require less ROW width than do lattice structures. More expensive though 36

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38 Transmission Right of Way 500 kv Single circuit 150 feet Two circuits in same ROW 300 feet Separate pole lines Single circuit along road ROW 70 feet If the road ROW has landscaping and burming, this can decrease the need for additional transmission ROW since the transmission can overhang 38

39 Transmission Right of Way 345 kv Single circuit 130 feet Two circuits in same ROW 300 feet Single circuit along road ROW 60 ft If the road ROW has landscaping and burming, this can decrease the need for additional transmission ROW since the transmission can overhang 39

40 Transmission Right of Way 230 kv Double circuit (same tower) 80 feet Normally we will run double circuits for 230 kv Double circuit along road Row 40 feet If the road ROW has landscaping and berming, this can decrease the need for additional transmission ROW since the transmission can overhang 40

41 230 kv transmission on Eagle Road Note the transmission line is in road rightof-way. 41

42 Increasing Capacity of Existing Lines The capacity of existing transmission lines can sometimes be increased Increase wire size If structurally able Increase voltage If electrical clearances are great enough If ROW is available If the line was already serving an end-load, that load still must be served Still must meet reliability criteria 42

43 Small Group Discussion What are important issues to consider when locating transmission lines in the Treasure Valley? (What are the most important?) Where would you like to see transmission lines enter the Treasure Valley? Explore the possible corridors that transmission lines could use to cross the Treasure Valley 43

44 A Buildout Scenario

45 Brownlee Ontario Existing 2004 Locust Caldwell Midpoint Boise Bench GEN Mt. Home 45

46 Brownlee Ontario Nampa 230 Caldwell Nampa Boise Bench Midpoint GEN Mt. Home 46

47 Brownlee Ontario Happy Valley 230 Caldwell Nampa Happy Valley Boise Bench GEN Mt. Home Midpoint 47

48 Brownlee Ontario Middleton Middleton Caldwell Nampa Boise Bench Midpoint GEN Mt. Home 48

49 Brownlee Ontario Pearl Pearl to Middleton Middleton Caldwell Switching Station Boise Bench GEN Mt. Home Midpoint 49

50 Brownlee Ontario Pearl Pearl to Locust Locust Caldwell Midpoint Boise Bench GEN Mt. Home 50

51 Brownlee Ontario Pearl Pearl to Happy Valley Caldwell Midpoint Happy Valley Boise Bench GEN Mt. Home 51

52 Brownlee Ontario Mora 230 Caldwell Midpoint Mora Boise Bench GEN Mt. Home 52

53 Brownlee Ontario MORA to Mt Home Caldwell Midpoint Mora Boise Bench GEN Mt. Home 53

54 Brownlee Ontario MORA to Cloverdale Sub Caldwell Cloverdale Mora Boise Bench GEN GEN Mt. Home Midpoint 54

55 Brownlee Ontario Cloverdale Tap Caldwell Cloverdale Mora Boise Bench GEN GEN Mt. Home Midpoint 55

56 Brownlee Ontario Dry Creek Dry Creek Caldwell Midpoint Boise Bench GEN GEN Mt. Home 56

57 Brownlee Ontario Nampa to Cloverdale Caldwell Nampa Cloverdale Boise Bench GEN GEN Mt. Home Midpoint 57

58 Brownlee Ontario Midpoint to Southwest Treasure Valley Caldwell Midpoint Boise Bench GEN GEN Mt. Home Midpoint PacifiCorp Southwest TV 58

59 Brownlee Ontario Southwest Treasure Valley to Western Canyon County Caldwell Midpoint Boise Bench GEN GEN Mt. Home Midpoint PacifiCorp Southwest TV 59

60 Northwest Brownlee Ontario Southwest Treasure Valley to Northwest Caldwell Midpoint Boise Bench GEN GEN Mt. Home Midpoint PacifiCorp Southwest TV 60

61 Northwest Brownlee Ontario Convert Bowmont Sub to 230 Caldwell Midpoint Boise Bench GEN GEN Mt. Home Midpoint PacifiCorp Southwest TV 61

62 Northwest Brownlee Ontario Treasure Valley Build-Out Caldwell Midpoint Boise Bench GEN GEN Mt. Home Midpoint PacifiCorp Southwest TV 62