2022 PC3 California Renewable Portfolio Standard (RPS) Net-Short Out-of-State Study Report

PC3 Out-of-State CA RPS Net-Short Sensitivity

(PC3 Out-of-State CA RPS Net-Short Sensitivity September 19, 2013)

Introduction

The purpose of the 2022 PC3 Out-of-State California RPS Net-Short Sensitivity study is to examine the impact on transmission congestion and generation dispatch of increasing the amount of out-of-state resources assumed in the California (CA) renewable resource portfolio as compared to the 2022 Common Case.

Key Questions

Results from the Out-of-State California RPS Net-Short Sensitivity study are intended to address the following key questions.

1. What impact would additional out-of-state renewable resources have on transmission flows within California?

2. What impact would additional out-of-state renewable resources have on transmission flows across the Western Interconnection?

3. How does the generation dispatch, and particularly that of gas-fired generation, change in CA and across the Western Interconnection with increased out-of-state renewable resources?

4. What benefits are provided by the addition of a transmission line between Idaho and Nevada?

Study Limitations

The amount of out-of-state renewable resources modeled as part of the CA Renewable Portfolio Standard (RPS) resource portfolio may need to be adjusted if it is determined that increasing the out-of-state resources to the levels requested violates restrictions set forth in CA’s RPS legislation.

Input Assumptions

All 2022 study cases are constructed from the 2022 Common Case. As such, a number of the assumptions used to construct the 2022 Common Case are carried through to each subsequent study. The following assumptions are those specific to this study and may be in addition to or an alternative of those assumptions used in the Common Case.

· Loads – No change to 2022 Common Case loads

· Transmission System

· Initial run PC3a – No change to 2022 Common Case transmission

· Expansion run PC3b – Added the South West Intertie Project (SWIP) North

· Generation – 11,168 GWh of in-state CA RPS resources were replaced by out-of-state renewables. This is the amount of energy produced by in-state renewable resources assumed to be part of the CA RPS resource portfolio in the 2022 Common Case that were not existing, under-construction, or designated as a California Public Utility Commission (CPUC) discounted core resource needed to create a fifty-fifty split between in-state and out-of-state RPS net-short[footnoteRef:1] resources. [1: The RPS net-short is calculated for purposes of this study as the RPS energy requirement less energy produced by existing renewable resources.]

Repackaging California RPS

The California renewable generation portfolio assumed in the 2022 Common Case was derived from a combination of the Loads and Resources data submittals and the CPUC modified cost-constrained resource stack. The in-state RPS resources that were removed from the generation portfolio and the additional out-of-state resources that were added were selected from the CPUC’s modified cost-constrained resource stack. The results of this exercise are summarized in Table 1 and Figure 1.

Table 1: California RPS Adjustments for PC3 Out-of-State California RPS Net-Short Sensitivity

RPS Generation Mix

PC1

PC3

Change

CA RPS Existing Generation (GWh)

42,826

42,826

0

CA RPS Net-short In-state Generation (GWh)

33,889

22,721

-11,168

CA RPS Net-short Out-of-state Generation (GWh)

11,553

22,721

11,168

Total CA RPS (GWh)

88,268

88,268

0

Percent Total CA RPS -- In-state

79%

66%

-13%

-- Out-of-state

21%

34%

+13%

Figure 1: California RPS In/Out of State

Table 2 provides the summary details of where the generation was removed from and added to in order to increase the out-of-state proportion of the California renewable portfolio. Note the shift from geothermal and solar to wind resources. Although the annual energy is the same, several aspects of the generation in the portfolio cases are not, including capacity factor and installed capacity (MW).

Table 2: Renewable Changes for Out-of-State Study

Generation Changes (GWh)

Biomass

Geothermal

Small Hydro

Solar CSP0

Solar PV

Wind

CA RPS Net-short Removed

CA – Imperial (IID)

3,821

120

CA – San Diego (SDGE)

467

448

CA – South (SCE)

14

1,132

3,988

CA – North (PG&E)

1,178

<< Total Removed >>

14

3,821

0

1,132

467

5,734

CA RPS Net-short Added

Oregon

814

17

7,013

Colorado

621

Nevada

250

5

Utah

63

Wyoming

11

2,457

<< Total Added >>

814

250

96

0

0

10,091

Study Results

The following study results are organized according to the key questions associated with this study. Additional results of interest are also outlined.

Transmission Flows within California

The majority of in-state renewable resources removed in this study were removed from southern California while the majority of resources added out-of-state were added in Oregon. As a result, more surplus generation was made available in the Northwest which could flow into southern California and replace energy lost from the in-state California renewables resources that were removed. As a result of this generation shift, the utilization of Path 15 Midway-Los Banos (south-to-north flow) and Path 42 Imperial Irrigation District (IID)-Southern California Edison (SCE) decreased while the utilization of Path 26 increased (north-to-south flow).

Figure 2: Duration Plots for Path 15

Flow for Path 26, illustrated in Figure 3, increased from what was observed in the 2022 Common Case. This is mostly due to the resources added in the Northwest trying to reach load in southern California by flowing on this path.

Figure 3: Duration Plots for Path 26

Flow on Path 42 is shown in Figure 4. Flow decreased from the 2022 Common Case levels because geothermal resources in IID assumed in the 2022 Common Case were removed in this sensitivity, thus resulting in lower IID-SCE flow. Figure 5 shows that the flows on Path 43 did not change.

Figure 4: Duration Plots for Path 42

Figure 5: Duration Plots for Path 43

Transmission Impacts Overall

The paths between the Northwest and California were among the most significantly impacted as a result of the shift of renewable resources outside of California. Since the majority of the relocated renewable resources were sited in Oregon, this is not surprising. Figure 6 illustrates the most congested paths observed in the Out-of-State California RPS Net-Short Sensitivity study and Figure 7 provides a comparison of path utilization between the 2022 Common Case and the Out-of-State California RPS Net-Short Sensitivity study.

The decrease in the utilization of Path 8 seen in Figure 7 highlights the effect of must-take resources, such as wind, on the dispatch of other resources. The amount of Colstrip generation that was displaced increased from 1,169 GWh in the 2022 Common Case to 1,501 GWh in the Out-of-State California RPS Net-Short Sensitivity study most likely due to the addition of incremental wind resources in Oregon.

Figure 6: Most Heavily Utilized Paths - PC-3a

Figure 7: Change in Utilization for the Most Utilized Paths

The duration plot for Path 65 Pacific DC Intertie (PDCI) and Path 66 California-Oregon Intertie (COI), combined in Figure 8, shows the extent of the increased flow in the Out-of-State California RPS Net-Short Sensitivity study compared to the 2022 Common Case. The increase is consistent with the 7,844 GWh of renewable energy that was moved to the Northwest, which is equivalent to about 900 aMW/hr.

Figure 8: Duration plot for combined path 65 plus 66

The duration plot for Path 27 Intermountain Power Project (IPP) DC-line in Figure 9 shows part of the impact of moving a portion of the renewable resources from California to out-of-state locations. Doing so removes ‘zero cost’ energy from inside California. California load still must be satisfied and in this instance, importing power from IPP via Path 27 is an economic alterative, as shown the increased path flows.

Figure 9: Duration plot comparison for path 27

Figure 10 provides a summary of the changes in subregional energy transfers from the 2022 Common Case to the Out-of-State California RPS Net-Short Sensitivity study. Every transfer into California increased as expected. Since a majority of the resources removed from California were previously located in southern California (see Table 2), a substantial amount of the relocated energy was needed to replace the lost generation.

Figure 10: Comparison of Regional Transfers

The flows on Path 8 Montana to Northwest (see Figure 11) decreased slightly due to the influx of new generation in Oregon that displaced some of the coal imports from Montana.

Figure 11: Duration plot comparisons for Path 8

Impact on System Generation

The chart in Figure 12 shows the change in annual generation by resource type between the 2022 Common Case and the Out-of-State California RPS Net-Short Sensitivity study. Most visible is the shift from geothermal and solar generation (removed from California) to wind generation (added outside of California). There is also a change in dispatch from coal resources to combined cycle resources.

Figure 12: Change in Annual Generation by Type

The difference in annual energy by state/province is provided in Figure 13 and Figure 14. The renewable change was omitted from Figure 14 to improve the resolution of the other resource type changes.

Figure 13: Annual Generation by State/Province

Figure 14: Annual Generation (non-renewable) by State/Province

A 10-day plot of the load/generation balance during a period with high-wind output is shown in Figure 15. The priority given to wind and hydro forces curtailments of coal and nuclear resources. Since the added wind resources for the Out-of-State California RPS Net-Short Sensitivity study are not directly assigned to California loads, they are used by PROMOD to serve load in the Northwest. The same plot in economic stack[footnoteRef:2] order (see Figure 16) shows the type of generation that is being exported from the Northwest into California. [2: Generation pricing assumptions in the TEPPC studies do not reflect contract prices, which are often confidential. The assumed price for wind and solar energy, for example, is a negative $1,000/MWh. Actual contract prices for wind and solar are most often in the range of $40 to $120/MWh.]

Figure 15: Example of NWUS Dispatch

Figure 16: Example of NWUS Dispatch (stack order)

In the Northwest U.S. (NWUS) subregion, 3,285 GWh of coal and nuclear generation was displaced by wind and hydro resources during the study year.

A comparison of the daily wind output for all of the hour 4’s and hour 14’s is provided in Figure 17, both sorted from highest to lowest. This chart shows that over the study year (2022) there was more NWUS wind output at night (hour 4) than during the afternoon (hour 14). The total installed wind capacity in the NWUS subregion for the Out-of-State California RPS Net-Short Sensitivity study is 15,454 MW.

Figure 17: Wind Comparison - NWUS

A 10-day plot of the load/resource balance that includes the peak day for the NWUS subregion is shown in Figure 18. It is interesting to note that there are a number of off peak hours when the NWUS is resource deficient and is likely importing energy.

Figure 18: Sample Dispatch - NWUS with peak

Impact of Adding SWIP-N Transmission Project

The SouthWest Intertie Project (SWIP) consists of two phases – a southern phase that was included in the 2022 Common Case as a Common Case Transmission Assumption, and a northern phase that was not included. A map of the planned SWIP North (SWIP-N) project is provided in Figure 19.

Figure 19: Map of SWIP-North

The majority of the relocated energy in the Out-of-State California RPS Net-Short Sensitivity study was placed in the Northwest and Wyoming (see Table 2). It was thus expected that the SWIP-N line would enable the delivery of energy back to California via an alternate, less-constrained, and parallel path to the COI/PDCI. The hourly chronological flow on the SWIP-N transmission line in the expansion case is provided in Figure 20. The average flow was 838 MW north-to-south.

Figure 20: Hourly Flow on SWIP-N

The change in annual generation by type and state/province as a result of adding SWIP-N is provided in Figure 21. There was not a substantial change in annual generation as compared to the Out-of-State California RPS Net-Short Sensitivity study, but the SWIP-N project does appear to provide a means to deliver additional surplus coal resources to Nevada and California in order to lower the overall system variable production cost, which is the goal of the production cost model.

Figure 21: Generation Change by State/Province with SWIP-N

Another measure of the effectiveness of the SWIP-N line’s ability to help deliver the out-of-state resources is its impact on the regional transfers. Figure 22 shows that additional energy was delivered from the Northwest to southern California via the Basin and Desert Southwest (AZNMNV) subregions with the addition of the SWIP-N project. Note that SWIP-N is considered a path from Basin to AZNMNV.

Figure 22: Comparison of Regional Transfers

The change in path utilization between the 2022 Common Case and Out-of-State Net Short Sensitivity with SWIP North, and the Out-of-State California RPS Net-Short Sensitivity study are shown in Figure 23 and Figure 24, respectively. Adding the transmission project increased flows from AZNMNV to the California South (CA_S) subregion, and decreased flows from the NWUS to California North (CA_N), and from CA_N to CA_S, as shown on the chart. In all instances flows increased from the levels observed in the 2022 Common Case.

Figure 23: Change in Path Utilization - PC1 to PC3b (with SWIP N)

Figure 24: Change in Path Utilization - PC3a to PC3b (SWIP N)

Other Observations

For the Western Interconnection overall, the hourly load requirements in the Out-of-State California RPS Net-Short Sensitivity study were generally met by dispatchable hydro, combined cycle, and combustion turbine resources as illustrated in Figure 25, a 10-day plot including the Western Interconnection peak on July 21. The plot also shows an example of the occasional curtailment of coal resources. The curtailment of base-load resources is more prevalent during periods of low loads, high hydro and high winds.

Figure 25: Sample Dispatch - WECC

Study Summary

A summary of the key results from both the In-state and Out-of-State California RPS Net-Short Sensitivities is provided in Table 3. The changes observed were not significant and inclusion of the SWIP-N project in the Out-of-State California RPS Net-Short Sensitivity case increased deliverability of the relocated resources.

Table 3: Comparison of Key Results

Input or Result

PC1 Common Case

PC2 In-state Net Short

PC3a Out-of-state Net Short

PC3b Out-of-state Net Short w/ SWIP-N

CO2 Emissions (MMetric Tons)

359

360

359

359

Variable Production Cost (M$)

14,851

14,867

14,913

14,891

Dump Energy (GWh)

397

396

522

470

Coal-fired Gen (GWh)

267,320

267,530

265,870

266,203

Combined Cycle Gen (GWh)

156,646

156,461

158,823

158,142

Biomass Gen (GWh)

13,573

14,453

14,209

14,302

DSM Gen (GWh)

199

195

205

203

Unutilized Coal (GWh)

6,901

6,691

8,350

8,017

In addition to the shift in location of the RPS resources from California to mostly Oregon and Wyoming, there was a significant shift in the type of resources (see Table 2). The out-of-state assumptions added primarily wind resources, which comprised 90 percent of the additions. The changes increased the transmission flows for the interties from Oregon to California, as well as the path between northern and southern California.

The shifts in location and type also impacted the generation results with displacement of coal and nuclear fueled resources in Oregon, Washington, and Wyoming, and increased combined cycle generation in California, Arizona, and Mexico.

It should be noted that the RPS resource assumptions used to develop the 2022 Common Case and both the In-State and Out-of-State California RPS Net-Short Sensitivities were based on the CPUC’s modified cost-constrained resource stack finalized in 2011. Since that time, RPS procurement and planning in California have moved towards greater emphasis on in-state resources, especially solar (in part reflecting declining solar Photovoltaic (PV) costs). Therefore, it is the belief of TEPPC’s California stakeholders that the RPS resource scenario depicted in the Out-of-State California RPS Net-Short Sensitivity case is not likely to occur over the 10 year horizon considered in the study. However, greater California reliance on imported renewable energy is somewhat more plausible over a longer planning horizon if there is an increase in California’s RPS goal, but only if the present trend towards solar is slowed or reversed, policy and technical barriers to high levels of renewable energy imports are eased, and other states do not substantially increase their own RPS targets and seek to purchase increased wind energy from the Northwest.

California RPS Comparison (GWh)

CA RPS Existing GenPC1PC34282642826CA RPS Net-short In-statePC1PC33388922721CA RPS Net-short Out-of-statePC1PC31155322721

Page 1 of 22

Page 2 of 22

-4000-3000-2000-10000100020003000400050006000

Megawatts

P15 Midway-LosBanos Path Duration Plots

2010PC1_CCPC3a_CA_Outstate

S->N

-4000-3000-2000-1000010002000300040005000

Megawatts

P26 Northern-Southern California Path Duration Plots

2010PC1_CCPC3a_CA_Outstate

N->S

-2000-1500-1000-5000500100015002000

Megawatts

P42 IID-SCE Path Duration Plots

2010PC1_CCPC3a_CA_Outstate

E->W

-3000-2000-10000100020003000

Megawatts

P43 North of San Onofre Path Duration Plots

2010PC1_CCPC3a_CA_Outstate

S->N

0%10%20%30%40%50%60%70%

Most Heavily Utilized Paths -PC3a CA RPS OOS no xmisn

U75U90U99

-10%-5%0%5%10%15%P26 Northern-Southern CaliforniaP45 SDG&E-CFEInterstate WA-BC WestP66 COIP03 Northwest-British ColumbiaP08 Montana to NorthwestP47 Southern New Mexico (NM1)P29 Intermountain-Gonder 230 kVP79 TOT 2B2P27 Intermountain Power Project DC LineP11 West of CrossoverP22 Southwest of Four CornersInterstate WA-BC EastP60 Inyo-Control 115 kV TieP01 Alberta-British Columbia

Change in Utilization -PC1 to PC3a

U75U90U99

-8000-6000-4000-20000200040006000800010000

Megawatts

Interstate COI plus PDCI Path Duration Plots

20082010PC1_CCPC3a_CA_Outstate

N->S

-2000-1500-1000-500050010001500200025003000

Megawatts

P27 Intermountain Power Project DC Line Path Duration Plots

20082010PC1_CCPC3a_CA_Outstate

N->S

(500)0500100015002000250030003500

AZNMNV

To Ca_S

Basin To

AZNMNV

Basin To

Ca_N

Basin To

Ca_S

Ca_N To

Ca_S

Canada

To NWUS

NWUS To

Basin

NWUS To

Ca_N

NWUS To

Ca_S

RMPA To

AZNMNV

RMPA To

Basin

Average Megawatts

Transfers between Sub -Regions (aMW)

PC1 CCPC3a CA-NS OOS

-2000-1500-1000-50005001000150020002500

Megawatts

P08 Montana to Northwest Path Duration Plots

20082010PC1_CCPC3a_CA_Outstate

E->W

(4,000)(2,000)02,0004,0006,000Conventional HydroPumped StorageSteam - CoalSteam - OtherNuclearCombined CycleCombustion TurbineCogenerationICNegative Bus LoadBiomass RPSGeothermalSmall Hydro RPSSolarWind GWh

Annual Energy Difference: 2022 PC1 Common Case vs. 2022 PC3a CA OOS Net-short Sensitivity -No Xmisn Added

-12,000-10,000-8,000-6,000-4,000-2,00002,0004,0006,0008,000

GWh

Annual Energy Difference: 2022 PC1 Common Case vs. 2022 PC3a CA OOS Net -short Sensitivity -No Xmisn Added

Hydro+PSSteam - BoilerCombined CycleCombustion TurbineCogenerationRenewableOther

-50005001,0001,5002,000

GWh

Annual Energy Difference: 2022 PC1 Common Case vs. 2022 PC3a CA OOS Net -short Sensitivity -No Xmisn Added

Hydro+PSSteam - BoilerCombined CycleCombustion TurbineCogenerationOther

Excluding Renewable Generation

05,00010,00015,00020,00025,00030,00035,00011/5/202211/6/202211/7/202211/8/202211/9/202211/10/202211/11/202211/12/202211/13/202211/14/2022

NWUS Load/Gen Balance Snapshot -PC3a -CA OOS Net-short

DSMOther Combustion Turbine Steam - Other Combined Cycle Biomass RPS Geothermal Small Hydro RPSHydro+PS Solar Wind Steam - Coal NuclearDemand Dump

MW

05,00010,00015,00020,00025,00030,00035,00011/5/202211/6/202211/7/202211/8/202211/9/202211/10/202211/11/202211/12/202211/13/202211/14/2022

NWUS Load/Gen Balance Snapshot -PC3a -CA OOS Net-short (stack order)

DSMOther Combustion Turbine Steam - Other Combined Cycle Biomass RPS Steam - Coal Nuclear Geothermal Small Hydro RPSHydro+PS Solar WindDemand Dump

MW

020004000600080001000012000140001600011223344556677889100111122133144155166177188199210221232243254265276287298309320331342353364

Megawatts

Duration Plot -PC3a NWUS Wind Hour 4 vs. Hour 14

Hour 4Hour 14

Daily -Sorted Largest to Smallest

05,00010,00015,00020,00025,00030,00035,00012/8/202212/9/202212/10/202212/11/202212/12/202212/13/202212/14/202212/15/202212/16/202212/17/2022

NWUS Load/Gen Balance Snapshot -PC3a -CA OOS Net-short (stack order)

DSMOther Combustion Turbine Steam - Other Combined Cycle Biomass RPS Steam - Coal Nuclear Geothermal Small Hydro RPSHydro+PS Solar WindDemand Dump

MW

-5000500100015002000

SWIP North Path Flow (MW)

-800-700-600-500-400-300-200-1000100200

GWh

Annual Energy Difference: 2022 PC3a CA OOS Net -short NoTrnsm vs. 2022 PC3b CA OOS Net-short w SWIP N

Hydro+PSSteam - BoilerCombined CycleCombustion TurbineCogenerationRenewableOther

(500)0500100015002000250030003500

AZNMNV

To Ca_S

Basin To

AZNMNV

Basin To

Ca_N

Basin To

Ca_S

Ca_N To

Ca_S

Canada

To NWUS

NWUS To

Basin

NWUS To

Ca_N

NWUS To

Ca_S

RMPA To

AZNMNV

RMPA To

Basin

Average Megawatts

Transfers between Sub -Regions (aMW)

PC1 CCPC3a CA-NS OOSPC3b CA-NS OOSwSWIP-N

-10%-8%-6%-4%-2%0%2%4%6%8%10%12%P26 Northern-Southern CaliforniaP45 SDG&E-CFEP08 Montana to NorthwestInterstate WA-BC WestP03 Northwest-British ColumbiaP66 COIP47 Southern New Mexico (NM1)P79 TOT 2B2P27 Intermountain Power Project DC LineP11 West of CrossoverP22 Southwest of Four CornersInterstate WA-BC EastP60 Inyo-Control 115 kV TieP01 Alberta-British ColumbiaP76 Alturas Project

Change in Utilization -PC1 to PC3b

U75U90U99

-6%-5%-4%-3%-2%-1%0%1%2%3%4%5%P26 Northern-Southern CaliforniaP45 SDG&E-CFEP08 Montana to NorthwestInterstate WA-BC WestP03 Northwest-British ColumbiaP66 COIP47 Southern New Mexico (NM1)P79 TOT 2B2P27 Intermountain Power Project DC LineP11 West of CrossoverP22 Southwest of Four CornersInterstate WA-BC EastP60 Inyo-Control 115 kV TieP01 Alberta-British ColumbiaP76 Alturas Project

Change in Utilization -PC3a to PC3b

U75U90U99

020,00040,00060,00080,000100,000120,000140,000160,000180,000200,0007/14/20227/15/20227/16/20227/17/20227/18/20227/19/20227/20/20227/21/20227/22/20227/23/2022

WECC Load/Gen Balance Snapshot -PC3a CA OOS Net Short

DSMOther Combustion Turbine Steam - Other Combined Cycle Biomass RPS Geothermal Small Hydro RPSHydro+PS Solar Wind Steam - Coal NuclearDemand Dump

MW