National Grid. Niagara Mohawk Power Corporation INVESTIGATION AS TO THE PROPRIETY OF PROPOSED ELECTRIC TARIFF CHANGES. Testimony and Exhibits of:

Transcription

1 National Grid Niagara Mohawk Power Corporation INVESTIGATION AS TO THE PROPRIETY OF PROPOSED ELECTRIC TARIFF CHANGES Testimony and Exhibits of: Revenue Requirements Panel Exhibits (RRP-6), (RRP-7), (RRP-8), (RRP-9) and (RRP-11) Book 13 January 29, 2010 Submitted to: New York Public Service Commission Docket No. 10-E- Submitted by:

2 Exhibit (RRP-6)

3 Exhibit (RRP-6) NIAGARA MOHAWK POWER COPORATION d/b/a NATIONAL GRID Electric Rate Base for the Year Ended September 30, 2009 and Rate Years Ending December 31, 2011, December 31, 2012 and December 31, 2013 Summary Dated: January 29,

4 Exhibit (RRP-6) Summary Sheet 1 of 3 Exhibit (RRP-6) Summary Sheet 1 of 3 NIAGARA MOHAWK POWER CORPORATION d/b/a NATIONAL GRID (COMPANY 36) Summary of Electric Rate Base For the Year Ended September 30, 2009 and the Rate Year Ending December 31, 2011 ($000's) Adj. to Normalize Historic Year and Historic Year Ended Reflect Conditions Rate Year Ending Reference September 30, 2009 in the Rate Year December 31, 2011 Net Utility Plant Schedule 1 $ 4,182,257 $ 561,178 $ 4,743,434 Regulatory Assets / Liabilities Schedule 2 1,568,516 (977,710) 590,806 Accumulated Deferred Income Taxes - Federal Schedule 3 (1,101,097) 33,572 (1,067,526) Accumulated Deferred Income Taxes - State Schedule 3 (48,011) (90,261) (138,272) Working Capital Materials and supplies Exhibit RRP-6, Schedule 6, Sheet 19 26, ,421 Prepayments Exhibit RRP-6, Schedule 6, Sheet 20 (79,927) (2,569) (82,496) O&M Cash Allowance (1/8 O&M exp) Schedule 4 82,136 23, ,125 Supply Cash Allowance (Sept 09 lead/lag study) Schedule 5 33,582 33,582 Change in Supply Cash Allowance (3.64 % x RY PP exp) Schedule 5 0 2,635 2,635 subtotal Working Capital 28,776 58,491 87,267 subtotal avg. before EBCAP adj. 4,630,441 (450,948) 4,215,710 Excess Earnings Base adjustment Schedule 6 (64,057) (33,582) (97,639) Total Electric Rate Base $ 4,566,384 $ (448,313) $ 4,118, % General inflation 2

5 Exhibit (RRP-6) Summary Sheet 2 of 3 Exhibit (RRP-6) Summary Sheet 2 of 3 NIAGARA MOHAWK POWER CORPORATION d/b/a NATIONAL GRID (COMPANY 36) Summary of Electric Rate Base For the Rate Year Ended December 31, 2011 and the Rate Year Ending December 31, 2012 ($000's) Rate Year Ending Reflect Conditions Rate Year Ending Reference December 31, 2011 in the Rate Year 2 December 31, 2012 Net Utility Plant Schedule 1 $ 4,743,434 $ 388,363 $ 5,131,797 Regulatory Assets / Liabilities Schedule 2 590,806 (227,358) 363,448 Accumulated Deferred Income Taxes - Federal Schedule 3 (1,067,526) 13,277 (1,054,249) Accumulated Deferred Income Taxes - State Schedule 3 (138,272) (15,316) (153,588) Working Capital Materials and supplies Exhibit RRP-6, Schedule 6, Sheet 19 27, ,915 Prepayments Exhibit RRP-6, Schedule 6, Sheet 20 (82,496) (1,485) (83,981) O&M Cash Allowance (1/8 O&M exp) Schedule 4 106, ,134 Supply Cash Allowance (Sept 09 lead/lag study) Schedule 5 33, ,582 Change in Supply Cash Allowance (5.66% x RY PP exp) Schedule 5 2, ,176 subtotal Working Capital 87,267 (441) 86,826 subtotal avg. before EBCAP adj. 4,215, ,984 4,374,234 Excess Earnings Base adjustment Schedule 6 (97,639) 0 (97,639) Total Electric Rate Base $ 4,118,071 $ 158,525 $ 4,276, % General inflation 3

6 Exhibit (RRP-6) Summary Sheet 3 of 3 Exhibit (RRP-6) Summary Sheet 3 of 3 NIAGARA MOHAWK POWER CORPORATION d/b/a NATIONAL GRID (COMPANY 36) Summary of Electric Rate Base For the Rate Year Ended December 31, 2012 and the Rate Year Ending December 31, 2013 ($000's) Rate Year Ending Reflect Conditions Rate Year Ending Reference December 31, 2012 in the Rate Year 3 December 31, 2013 Net Utility Plant Schedule 1 $ 5,131,797 $ 466,254 $ 5,598,052 Regulatory Assets / Liabilities Schedule 2 363,448 (222,055) 141,393 Accumulated Deferred Income Taxes - Federal Schedule 3 (1,054,249) (5,780) (1,060,028) Accumulated Deferred Income Taxes - State Schedule 3 (153,588) (20,763) (174,351) Working Capital Materials and supplies Exhibit RRP-6, Schedule 6, Sheet 19 27, ,445 Prepayments Exhibit RRP-6, Schedule 6, Sheet 20 (83,981) (1,596) (85,577) O&M Cash Allowance (1/8 O&M exp) Schedule 4 106,134 (319) 105,815 Supply Cash Allowance (Sept 09 lead/lag study) Schedule 5 33, ,582 Change in Supply Cash Allowance (5.66% x RY PP exp) Schedule 5 3,176 1,107 4,283 subtotal Working Capital 86,826 (278) 86,548 subtotal avg. before EBCAP adj. 4,374, ,272 4,591,613 Excess Earnings Base adjustment Schedule 6 (97,639) 0 (97,639) Total Electric Rate Base $ 4,276,596 $ 217,379 $ 4,493, % General inflation 4

7 SCHEDULE 1 Electric Net Utility Plant in Service 5

8 Exhibit (RRP-6) Schedule 1 Sheet 1 of 5 NIAGARA MOHAWK POWER CORPORATION d/b/a NATIONAL GRID (COMPANY 36) Monthly Balances of Electric Net Utility Plant Rate Year Ending December 31, 2011 ($000's) Electric Total Elec Plant Non-Interest Reserve for Net Utility Balance at Month End in Service Bearing CWIP Depreciation Plant in Service Depreciation (a) (b) (c) (d) (e) 1 Dec-10 (1/2 month) $ 3,362,191 $ 14,191 $ (1,199,660) $ 2,176,723 2 Jan-11 $ 6,787,645 $ 28,758 $ (2,406,779) $ 4,409,625 $ 15,045 3 Feb-11 $ 6,815,402 $ 28,622 $ (2,414,985) $ 4,429,039 $ 15,175 4 Mar-11 $ 6,845,934 $ 30,526 $ (2,421,381) $ 4,455,079 $ 15,235 5 Apr-11 $ 6,873,565 $ 30,728 $ (2,429,787) $ 4,474,506 $ 15,300 6 May-11 $ 6,898,094 $ 32,683 $ (2,437,749) $ 4,493,028 $ 15,361 7 Jun-11 $ 6,930,315 $ 34,001 $ (2,444,413) $ 4,519,903 $ 15,414 8 Jul-11 $ 6,954,950 $ 35,568 $ (2,452,888) $ 4,537,630 $ 15,485 9 Aug-11 $ 6,980,287 $ 37,997 $ (2,459,826) $ 4,558,459 $ 15, Sep-11 $ 7,024,279 $ 38,375 $ (2,464,389) $ 4,598,265 $ 15, Oct-11 $ 7,051,760 $ 40,783 $ (2,471,828) $ 4,620,715 $ 15, Nov-01 $ 7,087,354 $ 39,889 $ (2,469,654) $ 4,657,588 $ 15, Dec-11 (1/2 month) $ 3,565,118 $ 19,425 $ (1,237,322) $ 2,347,221 $ 15, Total Electric (Sum of Lines 1 to 13) 83,176, ,547 (29,310,660) 54,277, , Allocation of Common to Electric (Line 33) 3,714, ,642 (1,178,178) $ 2,643,431 $ 12, Total Electric w/ Common (Line 14 + Line 15) 86,891, ,190 (30,488,838) 56,921, , Average Monthly Balance (Line 16 / 12) $ 7,240,988 $ 43,182 $ (2,540,737) $ 4,743,434 Common Total Common Plant Non-Interest Reserve for Net Utility Balance at Month End in Service Bearing CWIP Depreciation Plant in Service Depreciation (a) (b) (c) (d) (e) 18 Dec-10 (1/2 month) $ 175,828 $ 5,010 $ (55,811) $ 125, Jan-11 $ 351,912 $ 11,999 $ (112,274) $ 251,637 $ 1, Feb-11 $ 360,646 $ 4,959 $ (112,329) $ 253,276 $ 1, Mar-11 $ 360,965 $ 6,635 $ (113,201) $ 254,399 $ 1, Apr-11 $ 361,081 $ 8,280 $ (114,284) $ 255,076 $ 1, May-11 $ 361,240 $ 10,602 $ (115,335) $ 256,507 $ 1, Jun-11 $ 361,381 $ 13,261 $ (116,353) $ 258,289 $ 1, Jul-11 $ 361,691 $ 16,853 $ (117,338) $ 261,206 $ 1, Aug-11 $ 368,036 $ 11,336 $ (115,792) $ 263,580 $ 1, Sep-11 $ 368,547 $ 12,917 $ (116,730) $ 264,734 $ 1, Oct-11 $ 369,206 $ 14,258 $ (117,829) $ 265,635 $ 1, Nov-01 $ 379,716 $ 5,924 $ (118,942) $ 266,698 $ 1, Dec-11 (1/2 month) $ 190,300 $ 3,429 $ (59,874) $ 133,855 $ 1, Total Common (Sum of Lines 18 to 30) 4,370, ,462 (1,386,092) 3,109,919 14, Electric Percentage of Common 85% 85% 85% 85% 33 Allocation to Electric (Line 31 * Line 32) 3,714, ,642 (1,178,178) 2,643,431 12, Average Monthly Balance (Line 33 / 12) $ 309,581 $ 8,887 $ (98,181) $ 220,286 Note: (1) Electric % Gas % Column (a) - Lines 1 through 13 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 1, Sheet Total Plant in Service line for respective month Column (a) - Lines 18 through 30 -Workpapers for Exhibit (RRP-6), Schedule 1,Workpaper 2, Sheet Total Plant in Service line for respective month Column (b) - Lines 1 through 13 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 1, Sheet NIBCWIP line for respective month Column (b) - Lines 18 through 30 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 2, Sheet NIBCWIP line for respective month Column (c) - Lines 1 through 13 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 1, Sheet Total Depreciation Reserve line for respective month Column (c) - Lines 18 through 30 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 2, Sheet Total Depreciation Reserve line for respective month Column (d) - Lines 1 through 13 - Column (a) + Column (b) + Column (c) Column (d) - Lines 18 through 30 - Column (a) + Column (b) + Column (c) Column (e) - Lines 2 through 13 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 1, Sheet 28 Total Depreciation Expense line for respective month Column (e) - Lines 19 through 30 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 2, Sheet 13 Total Depreciation Expense line for respective month 6

9 Exhibit (RRP-6) Schedule 1 Sheet 2 of 5 NIAGARA MOHAWK POWER CORPORATION d/b/a NATIONAL GRID (COMPANY 36) Monthly Balances of Electric Net Utility Plant Rate Year Ending December 31, 2012 ($000's) Electric Total Elec Plant Non-Interest Reserve for Net Utility Balance at Month End in Service Bearing CWIP Depreciation Plant in Service Depreciation (a) (b) (c) (d) (e) 1 Dec-11 (1/2 month) $ 3,565,118 $ 19,425 $ (1,237,322) $ 2,347,221 2 Jan-12 $ 7,160,781 $ 40,065 $ (2,482,023) $ 4,718,822 $ 15,922 3 Feb-12 $ 7,192,039 $ 40,431 $ (2,490,004) $ 4,742,467 $ 15,989 4 Mar-12 $ 7,287,159 $ 42,862 $ (2,495,195) $ 4,834,826 $ 16,056 5 Apr-12 $ 7,319,912 $ 42,917 $ (2,503,534) $ 4,859,295 $ 16,244 6 May-12 $ 7,348,826 $ 45,015 $ (2,511,416) $ 4,882,424 $ 16,315 7 Jun-12 $ 7,389,872 $ 45,888 $ (2,517,299) $ 4,918,460 $ 16,377 8 Jul-12 $ 7,419,278 $ 47,485 $ (2,525,692) $ 4,941,070 $ 16,466 9 Aug-12 $ 7,448,977 $ 50,156 $ (2,532,539) $ 4,966,594 $ 16, Sep-12 $ 7,491,611 $ 51,710 $ (2,537,844) $ 5,005,477 $ 16, Oct-12 $ 7,520,301 $ 54,467 $ (2,543,890) $ 5,030,878 $ 16, Nov-12 $ 7,555,058 $ 55,605 $ (2,550,924) $ 5,059,738 $ 16, Dec-12 (1/2 month) $ 3,797,887 $ 27,824 $ (1,278,410) $ 2,547,302 $ 16, Total Electric (Sum of Lines 1 to 13) 88,496, ,849 (30,206,092) 58,854, , Allocation of Common to Electric (Line 33) 3,976,330 21,869 (1,271,207) $ 2,726,992 $ 12, Total Electric w/ Common (Line 14 + Line 15) 92,473, ,718 (31,477,299) 61,581, , Average Monthly Balance (Line 16 / 12) $ 7,706,096 $ 48,810 $ (2,623,108) $ 5,131,797 Common Total Common Plant Non-Interest Reserve for Net Utility Balance at Month End in Service Bearing CWIP Depreciation Plant in Service Depreciation (a) (b) (c) (d) (e) 18 Dec-11 (1/2 month) $ 190,300 $ 3,429 $ (59,874) $ 133, Jan-12 $ 380,388 $ 9,248 $ (120,488) $ 269,149 $ 1, Feb-12 $ 380,543 $ 11,643 $ (121,599) $ 270,587 $ 1, Mar-12 $ 393,999 $ 148 $ (122,557) $ 271,590 $ 1, Apr-12 $ 394,152 $ 148 $ (123,718) $ 270,582 $ 1, May-12 $ 394,307 $ 148 $ (124,881) $ 269,573 $ 1, Jun-12 $ 394,443 $ 148 $ (126,027) $ 268,564 $ 1, Jul-12 $ 394,598 $ 148 $ (127,192) $ 267,555 $ 1, Aug-12 $ 392,180 $ 148 $ (125,784) $ 266,544 $ 1, Sep-12 $ 392,186 $ 148 $ (126,792) $ 265,542 $ 1, Oct-12 $ 388,317 $ 148 $ (125,800) $ 262,665 $ 1, Nov-12 $ 388,472 $ 148 $ (126,945) $ 261,675 $ 1, Dec-12 (1/2 month) $ 194,151 $ 74 $ (63,882) $ 130,343 $ 1, Total Common (Sum of Lines 18 to 30) 4,678,036 25,728 (1,495,538) 3,208,225 15, Electric Percentage of Common 85% 85% 85% 85% 33 Allocation to Electric (Line 31 * Line 32) 3,976,330 21,869 (1,271,207) 2,726,992 12, Average Monthly Balance (Line 33 / 12) $ 331,361 $ 1,822 $ (105,934) $ 227,249 Note: (1) Electric % Gas % Column (a) - Lines 1 through 13 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 1, Sheet Total Plant in Service line for respective month Column (a) - Lines 18 through 30 -Workpapers for Exhibit (RRP-6), Schedule 1,Workpaper 2, Sheet Total Plant in Service line for respective month Column (b) - Lines 1 through 13 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 1, Sheet NIBCWIP line for respective month Column (b) - Lines 18 through 30 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 2, Sheet NIBCWIP line for respective month Column (c) - Lines 1 through 13 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 1, Sheet Total Depreciation Reserve line for respective month Column (c) - Lines 18 through 30 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 2, Sheet Total Depreciation Reserve line for respective month Column (d) - Lines 1 through 13 - Column (a) + Column (b) + Column (c) Column (d) - Lines 18 through 30 - Column (a) + Column (b) + Column (c) Column (e) - Lines 2 through 13 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 1, Sheet 29 Total Depreciation Expense line for respective month Column (e) - Lines 19 through 30 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 2, Sheet 14 Total Depreciation Expense line for respective month 7

10 Exhibit (RRP-6) Schedule 1 Sheet 3 of 5 NIAGARA MOHAWK POWER CORPORATION d/b/a NATIONAL GRID (COMPANY 36) Monthly Balances of Electric Net Utility Plant Rate Year Ending December 31, 2013 ($000's) Electric Total Elec Plant Non-Interest Reserve for Net Utility Balance at Month End in Service Bearing CWIP Depreciation Plant in Service Depreciation (a) (b) (c) (d) (e) 1 Dec-12 (1/2 month) $ 3,797,887 $ 27,824 $ (1,278,410) $ 2,547,302 2 Jan-13 $ 7,629,464 $ 57,206 $ (2,564,264) $ 5,122,406 $ 16,900 3 Feb-13 $ 7,664,265 $ 57,750 $ (2,572,315) $ 5,149,700 $ 16,972 4 Mar-13 $ 7,826,819 $ 42,870 $ (2,558,985) $ 5,310,704 $ 17,046 5 Apr-13 $ 7,864,076 $ 42,380 $ (2,567,556) $ 5,338,901 $ 17,389 6 May-13 $ 7,897,175 $ 44,034 $ (2,575,669) $ 5,365,540 $ 17,469 7 Jun-13 $ 7,950,796 $ 43,238 $ (2,580,495) $ 5,413,539 $ 17,537 8 Jul-13 $ 7,984,371 $ 44,378 $ (2,589,172) $ 5,439,576 $ 17,652 9 Aug-13 $ 8,018,258 $ 46,632 $ (2,596,261) $ 5,468,629 $ 17, Sep-13 $ 8,061,395 $ 48,340 $ (2,602,350) $ 5,507,385 $ 17, Oct-13 $ 8,097,585 $ 50,586 $ (2,609,906) $ 5,538,264 $ 17, Nov-13 $ 8,137,839 $ 51,083 $ (2,617,038) $ 5,571,884 $ 17, Dec-13 (1/2 month) $ 4,090,919 $ 25,405 $ (1,311,692) $ 2,804,632 $ 18, Total Electric (Sum of Lines 1 to 13) 95,020, ,725 (31,024,112) 64,578, , Allocation of Common to Electric (Line 33) 3,954,119 1,465 (1,357,425) $ 2,598,159 $ 12, Total Electric w/ Common (Line 14 + Line 15) 98,974, ,190 (32,381,537) 67,176, , Average Monthly Balance (Line 16 / 12) $ 8,247,914 $ 48,599 $ (2,698,461) $ 5,598,052 Common Total Common Plant Non-Interest Reserve for Net Utility Balance at Month End in Service Bearing CWIP Depreciation Plant in Service Depreciation (a) (b) (c) (d) (e) 18 Dec-12 (1/2 month) $ 194,151 $ 74 $ (63,882) $ 130, Jan-13 $ 388,085 $ 143 $ (128,538) $ 259,691 $ 1, Feb-13 $ 388,235 $ 143 $ (129,682) $ 258,697 $ 1, Mar-13 $ 388,186 $ 143 $ (130,627) $ 257,702 $ 1, Apr-13 $ 388,334 $ 143 $ (131,769) $ 256,708 $ 1, May-13 $ 388,483 $ 143 $ (132,913) $ 255,713 $ 1, Jun-13 $ 388,615 $ 143 $ (134,040) $ 254,718 $ 1, Jul-13 $ 388,765 $ 143 $ (135,185) $ 253,723 $ 1, Aug-13 $ 386,342 $ 143 $ (133,759) $ 252,727 $ 1, Sep-13 $ 386,343 $ 143 $ (134,748) $ 251,738 $ 1, Oct-13 $ 386,492 $ 143 $ (135,886) $ 250,750 $ 1, Nov-13 $ 386,642 $ 143 $ (137,024) $ 249,761 $ 1, Dec-13 (1/2 month) $ 193,233 $ 72 $ (68,919) $ 124,386 $ 1, Total Common (Sum of Lines 18 to 30) 4,651,905 1,723 (1,596,971) 3,056,658 15, Electric Percentage of Common 85% 85% 85% 85% 33 Allocation to Electric (Line 31 * Line 32) 3,954,119 1,465 (1,357,425) 2,598,159 12, Average Monthly Balance (Line 33 / 12) $ 329,510 $ 122 $ (113,119) $ 216,513 Note: (1) Electric % Gas % Column (a) - Lines 1 through 13 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 1, Sheet Total Plant in Service line for respective month Column (a) - Lines 18 through 30 -Workpapers for Exhibit (RRP-6), Schedule 1,Workpaper 2, Sheet Total Plant in Service line for respective month Column (b) - Lines 1 through 13 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 1, Sheet NIBCWIP line for respective month Column (b) - Lines 18 through 30 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 2, Sheet NIBCWIP line for respective month Column (c) - Lines 1 through 13 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 1, Sheet Total Depreciation Reserve line for respective month Column (c) - Lines 18 through 30 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 2, Sheet Total Depreciation Reserve line for respective month Column (d) - Lines 1 through 13 - Column (a) + Column (b) + Column (c) Column (d) - Lines 18 through 30 - Column (a) + Column (b) + Column (c) Column (e) - Lines 2 through 13 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 1, Sheet 30 Total Depreciation Expense line for respective month Column (e) - Lines 19 through 30 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 2, Sheet 15 Total Depreciation Expense line for respective month 8

11 Exhibit (RRP-6) Schedule 1 Sheet 4 of 5 NIAGARA MOHAWK POWER CORPORATION d/b/a NATIONAL GRID (COMPANY 36) Capital Expenditures (CAPEX) Based on CAPEX Budget Classifications In-Svc/ (a) (b) (c) (d) (e) (f) Closing 6 mo Forecast Per FY11 - FY15 Capex Plan Rule Per FY10 FY11 FY12 FY13 FY14 FY15 TRANSMISSION PLANT 1 T Land, Land Rights, Roads & Trails (350, 359) 1 month T Substations (352, 353) 12 months 32,239,033 38,441,500 37,091,000 53,318,075 62,978,384 70,371,000 3 T Lines ( ) 6 months 62,040,927 91,278, ,742, ,140, ,781, ,678,243 4 Rotterdam Banks - (Part of NERR) 3/ ,300,000 17,700, ,000 5 NY 115KV Transformer Replace (Priority 4) 3 months 0 4,000,000 7,000,000 7,000,000 7,000,000 8,966,667 6 Gardenville Rebuild 3/14 390, ,000 2,660,000 36,430,000 22,960, ,090 7 Tonawanda Station 3/13 671,133 23,100,000 31,347,000 8,501,000 3,000, Tri-Lakes 1/ ,000, Turner Rd - New KV Station - Part of NERR 3/13 438,251 2,000,000 25,000,000 17,250, , Rotterdam - R/R 230KV FPE RHE CBs 3/15 39, ,000 1,600,000 4,000,000 15,000,000 47,000, Upgrade 115KV Clay Sub to BPS NPCC 9/11,12/11,3/12,6/12,9/12,3/13 508,855 9,750,000 8,000,000 11,000, Construct Southwest Station - Part of SG075 3/13 301,648 5,000,000 18,000,000 2,000, Porter-115KV upgrade to bulk power 12/11,3/12,6/12,9/12,12/12,3/13 65, ,000 12,000,000 12,000, NY Circuit Breaker Repl (Priority 4) 3 months 0 50, ,000 6,000,000 8,000,000 4,000, New Gardenville - TB#3 & TB#4 6/13 2,868,223 3,700, ,800,000 2,800, Spier Rotterdam Line #3 - Part of NERR 3/14 432,479 1,580,000 9,660,000 25,260,000 8,630, Luther Forest 3/ ,000, T Capitalization change 9 months 0 468,679 1,823,693 2,030,407 2,106,677 2,145, TOTAL Transmission Plant (Sum of Lines 1 to 18) 99,997, ,468, ,823, ,030, ,106, ,145,675 DISTRIBUTION PLANT 20 D Land, Land Rights & Asset Retirement Costs (360, 374) 1 month 1,012,500 1,920,000 2,076,000 2,245,000 2,428,000 2,626, D Substations (361,362, 363) 9 months 18,003,198 37,081,000 50,000,000 52,000,000 55,000,000 57,000, D Lines ( ) 3 months 86,422, ,118, ,203, ,524, ,090, ,929, D Line Transformers (368) 1 month 9,470,206 26,830,000 29,933,000 32,536,000 34,539,000 37,242, D Meters (370) 1 month 4,149,542 7,132,000 7,765,000 8,329,000 8,844,000 9,492, D Installations & Leases on Cust premises ( )) 1 month D Streetlighting (373) 3 months 4,110,500 10,672,000 11,629,000 11,782,000 9,323,000 9,733, D Capitalization change 6 months 0 2,254,291 8,444,835 8,460,203 8,609,507 8,793, TOTAL Distribution Plant (Sum of Lines 20 to 27) 123,168, ,007, ,050, ,876, ,833, ,815, Total Transmission & Distribution Capex (Line 19 + Line 28) 223,165, ,476, ,874, ,906, ,940, ,961,084 ELECTRIC GENERAL PLANT 30 Electric General Plant ( ) 1 month 5,831,596 3,246,500 5,394,000 5,584,000 5,776,000 5,978, NY EMS Replacement INVP /11 3,990,127 5,100,000 4,200,000 4,100, NY EMS Life Extension INVP1644 3/10 481, Tonawanda to Dewey/ N. Falls 11/10 0 2,000, Elec General Capitalization change 1 month -302,804-1,140,811-1,161,654-1,183,725-1,206, TOTAL Electric General Plant (Sum of Lines 30 to 34) 10,302,723 10,043,696 8,453,189 8,522,346 4,592,275 4,771, Total Tran, Dist & Electric General Equipment (Line 29 + Line ,468, ,520, ,327, ,428, ,532, ,732,868 COMMON GENERAL PLANT 37 Common General Plant ( ) 1 month 2,656,000 4,508,534 5,008,534 5,008,534 5,008,534 5,008, SOC Blg A Façade Repair 12/9, 12/10, 12/11 920,000 3,500,000 1,000, SOC Renovations (Bldg/ Floor) 3 months 7,500,000 10,500,000 2,000, North Albany - Renovations 8/11 250,000 4,000,000 4,000, HCB Control Center Renovations 3/ ,000 13,000, Saratoga / Wilton 11/11 0 2,000,000 8,000, HCB Renov./Ops Center Consol. 2/ ,000, Common General Capitalization change 1 month -774,109-3,110,371-3,167,146-3,227,322-3,288,641 Total Common General Plant (Sum of Lines 37 to 43 11,326,000 34,234,425 29,898,163 1,841,388 1,781,212 1,719,893 Column (a-f) - Lines 1 through 3 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 4 and Workpaper 5 combined for respective period Column (a-f) - Lines 4 through 17 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 5 for respective period Column (a-f) - Lines 20 through 26 and Line 30 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 3 for respective period Column (a-f) - Lines 31 through 32 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 6 for respective period Column (a-f) - Line 33 and Lines 38 through 43 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 7 for respective period Column (a-f) - Line 37 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 7 and Workpaper 8 combined for respective period Column (a-f) - Line 18, Line 27, Line 34 and Line 44 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 9, Sheet 1 for respective period 9

12 Exhibit (RRP-6) Schedule 1 Sheet 5 of 5 NIAGARA MOHAWK POWER CORPORATION d/b/a NATIONAL GRID (COMPANY 36) Cost of Removal (COR) Based on CAPEX Budget Classifications (a) (b) (c) (d) (e) (f) 6 mo Forecast Per FY11 - FY15 Capex/COR Plan Per FY10 FY11 FY12 FY13 FY14 FY15 TRANSMISSION PLANT 1 T Land, Land Rights, Roads & Trails (350, 359) T Substations (352, 353) 2,397,684 3,223,256 3,006,900 4,286,401 5,082,006 5,722,774 3 T Lines ( ) 4,614,114 7,653,551 10,355,811 12,954,605 17,089,602 19,166,040 4 Rotterdam Banks - (Part of NERR) ,511 1,428,292 65,058 5 NY 115KV Transformer Replace (Priority 4) 0 335, , , , ,195 6 Gardenville Rebuild 29,063 41, ,641 2,928,718 1,852,745 14,971 7 Tonawanda Station 49,914 1,936,897 2,541, , , Tri-Lakes Turner Rd - New KV Station - Part of NERR 32, ,697 2,026,704 1,386,780 12, Rotterdam - R/R 230KV FPE RHE CBs 2,962 41, , ,572 1,210,417 3,822, Upgrade 115KV Clay Sub to BPS NPCC 37, , , , Construct Southwest Station - Part of SG075 22, ,242 1,459, , Porter-115KV upgrade to bulk power 4,899 8, , , NY Circuit Breaker Repl (Priority 4) 0 4,192 72, , , , New Gardenville - TB#3 & TB#4 213, , , , Spier Rotterdam Line #3 - Part of NERR 32, , ,119 2,030, , Luther Forest T Capitalization change 0 39, , , , , TOTAL Transmission Plant (Sum of Lines 1 to 18) 7,436,988 15,132,000 22,928,000 28,140,000 29,220,000 30,020,000 DISTRIBUTION PLANT 20 D Land, Land Rights & Asset Retirement Costs (360, 374) 86, , , , , , D Substations (361,362, 363) 1,534,753 3,311,242 4,301,478 4,328,865 4,790,639 5,072, D Lines ( ) 7,367,449 14,030,297 12,749,839 12,697,228 13,857,141 14,587, D Line Transformers (368) 807,325 2,395,853 2,575,123 2,708,538 3,008,434 3,313, D Meters (370) 353, , , , , , D Installations & Leases on Cust premises ( )) D Streetlighting (373) 350, ,983 1,000, , , , D Capitalization change 0 201, , , , , TOTAL Distribution Plant (Sum of Lines 20 to 27) 10,500,000 21,700,000 22,200,000 22,300,000 24,200,000 25,700, Total Transmission & Distribution Capex (Line 19 + Line 28) 17,936,988 36,832,000 45,128,000 50,440,000 53,420,000 55,720,000 ELECTRIC GENERAL PLANT 30 Electric General Plant ( ) NY EMS Replacement INVP NY EMS Life Extension INVP Tonawanda to Dewey/ N. Falls Elec General Capitalization change TOTAL Electric General Plant (Sum of Lines 30 to 34) Total Tran, Dist & Electric General Equipment (Line 29 + Line 35) 17,936,988 36,832,000 45,128,000 50,440,000 53,420,000 55,720,000 COMMON GENERAL PLANT 37 Common General Plant ( ) 175, , ,602 1,500,000 1,500,000 1,500, SOC Blg A Façade Repair 60, ,963 45, SOC Renovations (Bldg/ Floor) 496, ,890 90, North Albany - Renovations 16, , , HCB Control Center Renovations 0 21, , Saratoga / Wilton 0 85, , HCB Renov./Ops Center Consol , Common General Capitalization change Total Common General Plant (Sum of Lines 37 to 43) 750,000 1,500,000 1,500,000 1,500,000 1,500,000 1,500,000 Column (a-f) - Lines 19, 28 and 44 - Workpapers for Exhibit (RRP-6), Schedule 1, Workpaper 10 for respective period Total cost of removal by function was allocated to the various categories based on the associated capital forecast within the function. 10

13 SCHEDULE 2 Regulatory Assets and Liabilities 11

14 NIAGARA MOHAWK POWER CORPORATION d/b/a NATIONAL GRID Forecast Balances of Electric Rate Base Regulatory Assets & Liabilities For the Rate Year Ending December 30, 2010 (000)'s Exhibit (RRP-6) Schedule 2 Sheet 1 of 58 Actual Forecast # Months Avg Bal Balance at Balance at Proposed Activity Description HYE 09/30/09 09/30/ /31/2010 Recovery Regulatory Assets & Liabilities with Proposed Recovery, EXCLUDED from Rate Base Pension Settlement Loss FY ,226 $ 31, Pension Expense Deferred - Electric 165, , OPEB Expense Deferred - Electric 269, , Pension/OPEB Curtailment/Settlement Gains (25,552) (38,406) Generation Stranded Cost Adjustments 2,873 2, PowerChoice Appendix E Netting 7,117 7,117 (451,014) (565,814) Total of Accounts w/ Recovery but NOT in Rate Base $ - $ - Regulatory Assets & Liabilities with Proposed Recovery, INCLUDED in Rate Base Storm Restoration Costs 162, ,919 $ 171, Power for Jobs Tax Credit 4,220 3,633 3, Customer Service Backout Credit 10,310 10,310 10, NYPA Transmission Access Charge (NTAC) 13,051 13,051 13, NYISO Tarriff Schedule Costs - Sch 1 85,451 85,451 85, NYISO Tarriff Schedule Costs - Sch 2 13,287 13,287 13, Generation Sale Incentive 18,556 18,556 18, Low Income Allow Discount Program 3,225 3,908 4, Elevated Voltage Deferral 8,440 10,214 19, Customer Service Backout Credit 107, , , Religious Rate Revenue Deferred 3,952 4,031 4, City of Buffalo - Settlement Agreement SC7 Standby Service Lost Revenue 1,054 12,239 14, SC7 Standby Svc. Lost Rev. Offset - (11,743) (14,104) SIR Program Costs 66,394 82, , Generation Stranded Cost Adjustments 31,773 32,074 33, Incent Return on Ret Funding 64,412 70,157 84, Amortization of Regulatory Asset (77,089) (65,265) (104,950) 24 Incremental Capex , Medicare Act Tax Benefit Defer (60,185) (67,331) (85,196) CSS-Conv Savings Electric (1,366) (1,382) (1,440) Electric Customer Service Penalties (24,040) (24,000) (24,000) PowerChoice Appendix E Netting (86,716) (86,716) (86,716) Electric deferrral for Prop Tax Normalization (171) (916) (2,487) Loss on Sale of Building (2,515) (2,780) (3,430) MRA Interest Savings Deferral (92,534) (92,534) (92,534) Petroleum Business Tax Audit Refund (5,753) (5,753) (5,753) Affiliate Rule Employee Transfer Credit (167) (167) (167) IRS Audit Refund Liability (89-90) (48) (48) (48) Electric Service Re-establishment Charge (464) (464) (464) Delay in Start Date (12,555) (12,555) (12,555) Currently Provided Incidental Services (452) (500) (526) NYS Sales Tax Refund ( ) (1,477) (1,477) (1,477) Economic Development Fund (27,256) (33,901) (38,406) Meter Read Connect/disconnect Service Charge (125) (127) (132) NYPA MOU (16,677) (16,677) (16,677) Bonus Depreciation Adjustment (22,804) (24,281) (27,763) Pens/OPEB Int on Recovery (4,146) (4,146) (4,146) Station Service Sales Growth Deferral (2,350) (2,350) (2,350) NYS GRT Refund (91-94) (3,300) (3,300) (3,300) MHP Program Deferral (331) (401) (580) New England Gas Merger Savings (1,896) (3,247) (8,289) KeySpan Energy Merger Savings 823 (3,118) (22,702) 24 Gratwick Park Property Credit - - (41) Federal Tax Refund - Elec (2,111) (2,393) (18,072) 24 Subtotal Accounts w/ Recovery Included in Rate Base $ 148,741 $ 174,084 $ 144,272 12

15 NIAGARA MOHAWK POWER CORPORATION d/b/a NATIONAL GRID Forecast Balances of Electric Rate Base Regulatory Assets & Liabilities For the Rate Year Ending December 30, 2010 (000)'s Exhibit (RRP-6) Schedule 2 Sheet 2 of 58 Actual Forecast # Months Avg Bal Balance at Balance at Proposed Activity Description HYE 09/30/09 09/30/ /31/2010 Recovery Other Regulatory Assets & Liabilities Included in Rate Base Enhanced Severance Plan 69 $ 56 $ NYPA Res Hydropwr Ben Recon 1, Nimo-SBC Prog Cost Def-Elec Def-d Loss-Sale of Oswego 1, NIMO - RPS Program Cost Deferred 1,008 1, NIMO - ExcsAFDC Elec Plt in Srv NYAFUDC - Elec Plnt in SV (91-96) NIMO - SBC Program Cost Deferred 533 1, NY - Electr Data Interchange Cost 3,849 3,849 3, NY Merger Empl Separation Cost 2,665 1, NY Merger Rate Plan Stranded Cost 1,446,151 1,201, ,105 Variable RDV - Transmission 3,315 9,508 Variable Rate Case Expense - 3, Transmission Hydro-One Transformer Project - 4, Electric R&D Ventures Deferral (28) (29) (29) NIMO-Purch ERC's Economic Dev (951) (951) (951) NIMO-Gain-Redmpt-8.35% Bonds (407) (377) (301) Variable NIMO IRS Audit Refund (83-84) (307) (307) (307) NIMO-Environ Ins Recovery-Net (841) NIMO-SBC Program Cost Deferred (333) NIMO-Exit Fees Deferred (4,224) (3,376) (1,423) Variable NIMO-SBC Prog Cost Def-Elec (9,562) (21,771) CTC Reset Reserve 13,936 2, NIMO-Serv Aggreg Lost Revenue (153) (175) Voltage Migration Fee Deferred (19) (19) (17) Variable Subtotal Other Reg. Assets in Rate Base 1,454,676 $ 1,190,536 $ 575,806 Other Regulatory Assets & Liabilities Excluded from Rate Base Environmental response Fund $ 385,459 $ 385, Asset Ret Oblig Reg Asset 4,069 4, Elec Swaps - Elec Supply 39,318 39, Temp State Assessment 18-A 23,013 23, Fas158 - Pension 435, , Fas158 - OPEB 179, , NIMO - Fuel Costs Deferred (729) (729) NIMO - Commodity Adj Clause 32,111 32, NIMO - Oth Postretire Benef Elec 9,474 6, Pension/Fas106 Purch Acctg Adj 82,212 36, NIMO-Transm Revenue Adj Clause (9,524) (9,524) Other Assets & Liabilities Included in Rate Base Unbilled Revenue - Electric 131, , ,887 Variable Unamort Debt Expense 18,612 21,455 18,974 Variable Unamort Loss Reacquired Debt 30,403 27,625 22,097 Variable TCC Auction Revenue (41,984) (19,590) (36,043) Variable NY-Nucl Fuel Disposal Costs (167,026) (167,216) (167,630) Variable Large Project Salvage (24) NYPA Res HydroPwr Beneft Recon (12,689) - - Subtotal Other Reg. Liabilities in Rate Base (40,948) $ 6,161 $ (18,715) Net Reg Assets & Liabilities Included in Rate Base 1,562,469 $ 1,370,781 $ 701,363 13

16 Exhibit (RRP-6) Schedule 2 Sheet 3 of 58 NIAGARA MOHAWK POWER CORPORATION d/b/a NATIONAL GRID Year End Forecast Balances of Electric Rate Base Regulatory Assets & Liabilities For the Rate Years Ending December 31, 2011, 2012 amd 2013 (000)'s Actual Forecast Forecast Forecast Forecast Balance at Balance at Balance at Balance at Balance at Activity Description 09/30/ /31/ /31/ /31/ /31/2013 Regulatory Assets & Liabilities with Proposed Recovery, INCLUDED in Rate Base Storm Restoration Costs $ 171,919 $ 171,919 85, Power for Jobs Tax Credit 3,633 3,633 1, Customer Service Backout Credit 10,310 10,310 5, NYPA Transmission Access Charge (NTAC) 13,051 13,051 6, NYISO Tarriff Schedule Costs - Sch 1 85,451 85,451 42, NYISO Tarriff Schedule Costs - Sch 2 13,287 13,287 6, Generation Sale Incentive 18,556 18,556 9, Low Income Allow Discount Program 3,908 4,232 2, Elevated Voltage Deferral 10,214 19,597 9, Customer Service Backout Credit 109, ,716 58, Religious Rate Revenue Deferred 4,031 4,225 2, City of Buffalo - Settlement Agreement SC7 Standby Service Lost Revenue 12,239 14,599 7, SC7 Standby Svc. Lost Rev. Offset (11,743) (14,104) (7,048) SIR Program Costs 82, ,992 54, Generation Stranded Cost Adjustments 32,074 33,260 16, Incent Return on Ret Funding 70,157 84,541 42, Amortization of Regulatory Asset (65,265) (104,950) (52,475) - - Incremental Capex - 18,526 9, Medicare Act Tax Benefit Defer (67,331) (85,196) (42,597) CSS-Conv Savings Electric (1,382) (1,440) (720) Electric Customer Service Penalties (24,000) (24,000) (12,000) PowerChoice Appendix E Netting (86,716) (86,716) (43,360) Electric deferrral for Prop Tax Normalization (916) (2,487) (1,239) Loss on Sale of Building (2,780) (3,430) (1,714) MRA Interest Savings Deferral (92,534) (92,534) (46,262) Petroleum Business Tax Audit Refund (5,753) (5,753) (2,873) Affiliate Rule Employee Transfer Credit (167) (167) (83) IRS Audit Refund Liability (89-90) (48) (48) (24) Electric Service Re-establishment Charge (464) (464) (236) Delay in Start Date (12,555) (12,555) (6,279) Currently Provided Incidental Services (500) (526) (262) NYS Sales Tax Refund ( ) (1,477) (1,477) (734) Economic Development Fund (33,901) (38,406) (19,206) Meter Read Connect/disconnect Service Charge (127) (132) (61) NYPA MOU (16,677) (16,677) (8,337) Bonus Depreciation Adjustment (24,281) (27,763) (13,879) Pens/OPEB Int on Recovery (4,146) (4,146) (2,070) Station Service Sales Growth Deferral (2,350) (2,350) (1,174) NYS GRT Refund (91-94) (3,300) (3,300) (1,645) MHP Program Deferral (401) (580) (292) New England Gas Merger Savings (3,247) (8,289) (4,148) KeySpan Energy Merger Savings (3,118) (22,702) (11,350) - - Gratwick Park Property Credit - (41) (17) Federal Tax Refund - Elec (2,393) (18,072) (9,036) - - Subtotal Accounts w/ Recovery Included in Rate Base $ 174,084 $ 144,272 $ 72,163 $ - $ - 14

17 Exhibit (RRP-6) Schedule 2 Sheet 4 of 58 NIAGARA MOHAWK POWER CORPORATION d/b/a NATIONAL GRID Year End Forecast Balances of Electric Rate Base Regulatory Assets & Liabilities For the Rate Years Ending December 31, 2011, 2012 amd 2013 (000)'s Actual Forecast Forecast Forecast Forecast Balance at Balance at Balance at Balance at Balance at Activity Description 09/30/ /31/ /31/ /31/ /31/2013 Other Regulatory Assets & Liabilities Included in Rate Base Enhanced Severance Plan NYPA Res Hydropwr Ben Recon Nimo-SBC Prog Cost Def-Elec Def-d Loss-Sale of Oswego NIMO - RPS Program Cost Deferred 1, NIMO - ExcsAFDC Elec Plt in Srv NYAFUDC - Elec Plnt in SV (91-96) NIMO - SBC Program Cost Deferred 1, NY - Electr Data Interchange Cost 3,849 3,849 1, NY Merger Empl Separation Cost 1, NY Merger Rate Plan Stranded Cost 1,201, , , ,007 63,299 RDV - Transmission 3,315 9,508 10,511 6,496 1,540 Rate Case Expense - 3,078 2,052 1,026 (0) Transmission Hydro-One Transformer Project - 4,125 2,625 1, Electric R&D Ventures Deferral (29) (29) (17) (5) NIMO-Purch ERC's Economic Dev (951) (951) (472) NIMO-Gain-Redmpt-8.35% Bonds (377) (301) (240) (180) (120) NIMO IRS Audit Refund (83-84) (307) (307) (152) NIMO-Environ Ins Recovery-Net NIMO-SBC Program Cost Deferred NIMO-Exit Fees Deferred (3,376) (1,423) NIMO-SBC Prog Cost Def-Elec (21,771) CTC Reset Reserve 2, NIMO-Serv Aggreg Lost Revenue (175) Voltage Migration Fee Deferred (19) (17) (16) (14) (13) Subtotal Other Reg. Assets in Rate Base 1,190, , , ,454 64,707 Other Regulatory Assets & Liabilities Excluded from Rate Base Environmental response Fund 385, , , , , Asset Ret Oblig Reg Asset 4,069 4,069 4,069 4,069 4, Elec Swaps - Elec Supply 39,318 39,318 39,318 39,318 39, Temp State Assessment 18-A 23,013 23,013 23,013 23,013 23, Fas158 - Pension 435, , , , , Fas158 - OPEB 179, , , , , NIMO - Fuel Costs Deferred (729) (729) (368) NIMO - Commodity Adj Clause 32,111 32,111 32,111 32,111 32, NIMO - Oth Postretire Benef Elec 9,474 6, Pension/Fas106 Purch Acctg Adj 82,212 36, NIMO-Transm Revenue Adj Clause (9,524) (9,524) (9,524) (9,524) (9,524) Other Assets & Liabilities Included in Rate Base Unbilled Revenue - Electric 143, , , , , Unamort Debt Expense 21,455 18,974 16,988 15,003 13, Unamort Loss Reacquired Debt 27,625 22,097 19,785 17,473 15, TCC Auction Revenue (19,590) (36,043) (36,043) (36,043) (36,043) NY-Nucl Fuel Disposal Costs (167,216) (167,630) (167,962) (168,295) (168,628) Large Project Salvage NYPA Res HydroPwr Beneft Recon Subtotal Other Reg. Liabilities in Rate Base $ 6,161 $ (18,715) $ (23,344) $ (27,974) $ (32,557) Net Reg Assets & Liabilities Included in Rate Base $ 1,370,781 $ 701,363 $ 457,339 $ 229,480 $ 32,150 15

18 Exhibit (RRP-6) Schedule 2 Sheet 5 of 58 NIAGARA MOHAWK POWER CORPORATION d/b/a NATIONAL GRID Average Forecast Balances of Electric Rate Base Regulatory Assets & Liabilities For the Rate Years Ending December 31, 2011, 2012 amd 2013 (000)'s Forecast Forecast Forecast Rate Base Rate Base Rate Base Avg Bal Avg Bal Avg Bal Avg Bal Activity Description HYE 09/30/09 RYE 12/31/11 RYE 12/31/12 RYE 12/31/13 Regulatory Assets & Liabilities with Proposed Recovery, INCLUDED in Rate Base Storm Restoration Costs 162, ,941 42, Power for Jobs Tax Credit 4,220 2, Customer Service Backout Credit 10,310 7,730 2, NYPA Transmission Access Charge (NTAC) 13,051 9,787 3, NYISO Tarriff Schedule Costs - Sch 1 85,451 64,091 21, NYISO Tarriff Schedule Costs - Sch 2 13,287 9,963 3, Generation Sale Incentive 18,556 13,918 4, Low Income Allow Discount Program 3,225 3,175 1, Elevated Voltage Deferral 8,440 14,696 4, Customer Service Backout Credit 107,012 88,286 29, Religious Rate Revenue Deferred 3,952 3,169 1, City of Buffalo - Settlement Agreement SC7 Standby Service Lost Revenue 1,054 10,951 3, SC7 Standby Svc. Lost Rev. Offset - (10,576) (3,520) SIR Program Costs 66,394 81,745 27, Generation Stranded Cost Adjustments 31,773 24,944 8, Incent Return on Ret Funding 64,412 63,404 21, Amortization of Regulatory Asset (77,089) (78,713) (26,237) - Incremental Capex - 13,894 4, Medicare Act Tax Benefit Defer (60,185) (63,897) (21,297) CSS-Conv Savings Electric (1,366) (1,080) (360) Electric Customer Service Penalties (24,040) (18,000) (6,000) PowerChoice Appendix E Netting (86,716) (65,038) (21,682) Electric deferrral for Prop Tax Normalization (171) (1,863) (615) Loss on Sale of Building (2,515) (2,572) (856) MRA Interest Savings Deferral (92,534) (69,398) (23,126) Petroleum Business Tax Audit Refund (5,753) (4,313) (1,433) Affiliate Rule Employee Transfer Credit (167) (125) (41) IRS Audit Refund Liability (89-90) (48) (36) (12) Electric Service Re-establishment Charge (464) (350) (122) Delay in Start Date (12,555) (9,417) (3,141) Currently Provided Incidental Services (452) (394) (130) NYS Sales Tax Refund ( ) (1,477) (1,106) (362) Economic Development Fund (27,256) (28,806) (9,606) Meter Read Connect/disconnect Service Charge (125) (97) (25) NYPA MOU (16,677) (12,507) (4,167) Bonus Depreciation Adjustment (22,804) (20,821) (6,937) Pens/OPEB Int on Recovery (4,146) (3,108) (1,032) Station Service Sales Growth Deferral (2,350) (1,762) (586) NYS GRT Refund (91-94) (3,300) (2,473) (817) MHP Program Deferral (331) (436) (148) New England Gas Merger Savings (1,896) (6,218) (2,078) KeySpan Energy Merger Savings 823 (17,026) (5,674) - Gratwick Park Property Credit - (29) (5) Federal Tax Refund - Elec (2,111) (13,554) (4,518) - Subtotal Accounts w/ Recovery Included in Rate Base 148, ,217 36,109-16

19 Exhibit (RRP-6) Schedule 2 Sheet 6 of 58 NIAGARA MOHAWK POWER CORPORATION d/b/a NATIONAL GRID Average Forecast Balances of Electric Rate Base Regulatory Assets & Liabilities For the Rate Years Ending December 31, 2011, 2012 amd 2013 (000)'s Forecast Forecast Forecast Rate Base Rate Base Rate Base Avg Bal Avg Bal Avg Bal Avg Bal Activity Description HYE 09/30/09 RYE 12/31/11 RYE 12/31/12 RYE 12/31/13 Other Regulatory Assets & Liabilities Included in Rate Base Enhanced Severance Plan NYPA Res Hydropwr Ben Recon 1, Nimo-SBC Prog Cost Def-Elec Def-d Loss-Sale of Oswego 1, NIMO - RPS Program Cost Deferred 1, NIMO - ExcsAFDC Elec Plt in Srv NYAFUDC - Elec Plnt in SV (91-96) NIMO - SBC Program Cost Deferred NY - Electr Data Interchange Cost 3,849 2, NY Merger Empl Separation Cost 2, NY Merger Rate Plan Stranded Cost 1,446, , , ,153 RDV - Transmission - 10,514 9,051 4,016 Rate Case Expense 2,565 1, Transmission Hydro-One Transformer Project - 3,375 1, Electric R&D Ventures Deferral (28) (23) (11) (1) NIMO-Purch ERC's Economic Dev (951) (712) (232) (213) NIMO-Gain-Redmpt-8.35% Bonds (407) (271) (210) (150) NIMO IRS Audit Refund (83-84) (307) (230) (88) (12) NIMO-Environ Ins Recovery-Net (841) NIMO-SBC Program Cost Deferred (333) NIMO-Exit Fees Deferred (4,224) (726) NIMO-SBC Prog Cost Def-Elec (9,562) CTC Reset Reserve 13, NIMO-Serv Aggreg Lost Revenue (153) Voltage Migration Fee Deferred (19) (16) (14) (14) Subtotal Other Reg. Assets in Rate Base 1,454, , , ,714 Other Assets & Liabilities Included in Rate Base Unbilled Revenue - Electric 131, , , , Unamort Debt Expense 18,612 17,981 15,288 14, Unamort Loss Reacquired Debt 30,403 20,941 18,513 16, TCC Auction Revenue (41,984) (25,078) (23,576) (25,078) NY-Nucl Fuel Disposal Costs (167,026) (167,796) (160,306) (168,462) Large Project Salvage (24) NYPA Res HydroPwr Beneft Recon (12,689) Subtotal Other Reg. Liabilities in Rate Base (40,948) (10,065) (6,194) (19,321) Net Reg Assets & Liabilities Included in Rate Base 1,562, , , ,393 17

20 Exhibit (RRP-6) Schedule 2 Sheet 7 of 58 NIAGARA MOHAWK POWER CORPORATION d/b/a NATIONAL GRID Rate Year Regualtory Asset Amortization For the Rate Years Ending December 31, 2011, 2012 amd 2013 (000)'s Rate Year Rate Year Rate Year Amortization Amortization Amortization Amortization Activity Description Period Cal 2011 Cal 2012 Cal 2013 Regulatory Assets & Liabilities with Proposed Recovery, INCLUDED in Rate Base Storm Restoration Costs 24 85,956 85, Power for Jobs Tax Credit 24 1,812 1, Customer Service Backout Credit 24 5,160 5, NYPA Transmission Access Charge (NTAC) 24 6,528 6, NYISO Tarriff Schedule Costs - Sch ,720 42, NYISO Tarriff Schedule Costs - Sch ,648 6, Generation Sale Incentive 24 9,276 9, Low Income Allow Discount Program 24 2,113 2, Elevated Voltage Deferral 24 9,803 9, Customer Service Backout Credit 24 58,860 58, Religious Rate Revenue Deferred 24 2,112 2, City of Buffalo - Settlement Agreement SC7 Standby Service Lost Revenue 24 7,296 7, SC7 Standby Svc. Lost Rev. Offset 24 (7,056) (7,048) SIR Program Costs 24 54,493 54, Generation Stranded Cost Adjustments 24 16,632 16, Incent Return on Ret Funding 24 42,275 42, Amortization of Regulatory Asset 24 (52,475) (52,475) - Incremental Capex 24 9,264 9, Medicare Act Tax Benefit Defer 24 (42,599) (42,597) CSS-Conv Savings Electric 24 (720) (720) Electric Customer Service Penalties 24 (12,000) (12,000) PowerChoice Appendix E Netting 24 (43,356) (43,360) Electric deferrral for Prop Tax Normalization 24 (1,248) (1,239) Loss on Sale of Building 24 (1,716) (1,714) MRA Interest Savings Deferral 24 (46,272) (46,262) Petroleum Business Tax Audit Refund 24 (2,880) (2,873) Affiliate Rule Employee Transfer Credit 24 (84) (83) IRS Audit Refund Liability (89-90) 24 (24) (24) Electric Service Re-establishment Charge 24 (228) (236) Delay in Start Date 24 (6,276) (6,279) Currently Provided Incidental Services 24 (264) (262) NYS Sales Tax Refund ( ) 24 (743) (734) Economic Development Fund 24 (19,200) (19,206) Meter Read Connect/disconnect Service Charge 24 (71) (61) NYPA MOU 24 (8,340) (8,337) Bonus Depreciation Adjustment 24 (13,884) (13,879) Pens/OPEB Int on Recovery 24 (2,076) (2,070) Station Service Sales Growth Deferral 24 (1,176) (1,174) NYS GRT Refund (91-94) 24 (1,655) (1,645) MHP Program Deferral 24 (288) (292) New England Gas Merger Savings 24 (4,141) (4,148) KeySpan Energy Merger Savings 24 (11,352) (11,350) - Gratwick Park Property Credit 24 (24) (17) Federal Tax Refund - Elec 24 (9,036) (9,036) - Subtotal Accounts w/ Recovery Included in Rate Base 72,109 72,163-18

21 Exhibit (RRP-6) Schedule 2 Sheet 8 of 58 NIAGARA MOHAWK POWER CORPORATION d/b/a NATIONAL GRID Rate Year Regualtory Asset Amortization For the Rate Years Ending December 31, 2011, 2012 amd 2013 (000)'s Rate Year Rate Year Rate Year Amortization Amortization Amortization Amortization Activity Description Period Cal 2011 Cal 2012 Cal 2013 Other Regulatory Assets & Liabilities Included in Rate Base Enhanced Severance Plan NYPA Res Hydropwr Ben Recon Nimo-SBC Prog Cost Def-Elec Def-d Loss-Sale of Oswego NIMO - RPS Program Cost Deferred NIMO - ExcsAFDC Elec Plt in Srv NYAFUDC - Elec Plnt in SV (91-96) NIMO - SBC Program Cost Deferred NY - Electr Data Interchange Cost 24 1,920 1, NY Merger Empl Separation Cost NY Merger Rate Plan Stranded Cost Variable 164, , ,708 RDV - Transmission Variable Rate Case Expense 36 Transmission Hydro-One Transformer Project 36 1,500 1,500 1, Electric R&D Ventures Deferral 24 (12) (12) (5) NIMO-Purch ERC's Economic Dev 24 (479) (472) NIMO-Gain-Redmpt-8.35% Bonds Variable (60) (60) (60) NIMO IRS Audit Refund (83-84) 24 (155) (152) (0) NIMO-Environ Ins Recovery-Net NIMO-SBC Program Cost Deferred NIMO-Exit Fees Deferred Variable (1,423) NIMO-SBC Prog Cost Def-Elec CTC Reset Reserve NIMO-Serv Aggreg Lost Revenue Voltage Migration Fee Deferred Variable (1) (1) (1) Subtotal Other Reg. Assets in Rate Base 167, , ,766 Other Assets & Liabilities Included in Rate Base NIMO - Fuel Costs Deferred 24 (361) (368) NIMO - Oth Postretire Benef Elec 12 6, Other Assets & Liabilities Included in Rate Base Unbilled Revenue - Electric Variable Unamort Debt Expense Variable Unamort Loss Reacquired Debt Variable TCC Auction Revenue Variable NY-Nucl Fuel Disposal Costs Variable Large Project Salvage NYPA Res HydroPwr Beneft Recon Subtotal Other Reg. Liabilities in Rate Base Net Reg Assets & Liabilities Included in Rate Base 245, , ,099 19