Base Point Deviation – Long Term Solutions

1. QSE Managers Working GroupOctober 12, 2010Base Point Deviation Issues – Two SolutionsNodal Settlement & Billing Group

2. Proposal A: The first alternative modifies the AABP calculation by incorporating a methodology to derive what the Base Point should have been for a shortened SCED interval. The derived Base Point is utilized in the AABP calculation rather than the 5-minute based SCED Base Point. Proposal B: The second alternative modifies the AABP calculation by using the data inputs calculated for the GREDP calculations. The GREDP data inputs are on a 5-minute clock basis and would not require the time-weighting and averaging that is currently part of the AABP calculation. Therefore, use of the GREDP data avoids the issue of shortened SCED intervals. Base Point Deviation – Long Term Solutions

3. Base Point Deviation – Proposal A: Derived Base Point

4. Base Point Deviation – Proposal A: Derived Base Point

5. AABP = [(BPSETy- TELGEN (y-1))/300*TLMPy] + TWAR BPSet y = Tel Geny-1 +Normal Ramp Rate/(300 Sec) * TLMPy(Sec) Where TWAR = ((ARI y * TLMP y) / (TLMP y) Tel Geny-1 = Telemetered Generation during the prior SCED interval Tel Geny= Telemetered Generation during the current SCED interval TLMP= Duration of SCED interval in seconds Where BPSet y = Tel Geny-1 +(BPy - Tel Geny-1)/300 * TLMPy Tel Geny-1 = Tel Generation in previous SCED interval, and (BPy - Tel Geny-1)/300 * TLMPy = MW change for current SCED interval based on the normal ramp rate for the TLMPy interval. Base Point Deviation – Proposal A: Derived Base Point Inputs

6. Once you alter the input AABP, the remainder of the formula is the same. TWTG becomes the incremental difference between the starting and ending Generation in the settlement interval. Over Generation: BPDAMT q, r, p= Max (0, RTSPP p) * Max [0, (TWTG q, r, p – ¼ * Max (((1 + K1) * AABP q, r, p), (AABP q, r, p + Q1)))] Where: TWTG q, r, p, i = (TelGen(i+1)- TelGeni ) K1 = 5 % Q1 = 5 MW Under Generation: BPDAMT q, r, p= Max (0, RTSPP p) * Min (1, KP) * Max {0, {Min [((1 – K2) * ¼( AABPq, r, p)) , ¼( AABPq, r, p – Q2 )] – TWTG q, r, p}} Where: TWTG q, r, p, i = (TelGen(i+1)- TelGeni ) K2 = 5 % Q2 = 5 MW Base Point Deviation – Proposal A: Derived Base Point

7. Base Point Deviation – Proposal B: GREDP Inputs

8. Base Point Deviation – Proposal B: GREDP Inputs 542.64 = Average BP + Average Regulation Instruction (ARI) / 3 180.88 = Average MW output / 3

9. AABP q, r, p, i = AVGBP q, r, p, i + AVGREG q, r, p, i Where: AVGBP q, r, p, i = (AVGBP y + AVGBP y-1 + AVGBP y-2)/3 AVGREG q, r, p, i = (AVGREG y + AVGREG y-1 + AVGREG y-2)/3 y = 5-minute clock interval (ARI) - The Average Regulation Instruction or ARI. Calculated as follows (AVG_REGUP_5M-AVG_REGDN_5M = ARI) Base Point Deviation – Proposal B: GREDP Inputs

10. Once you alter the input AABP, the remainder of the formula is the same. TWTG becomes the average telemetered generation for each 5-minute clock interval in the settlement interval. Over Generation: BPDAMT q, r, p= Max (0, RTSPP p) * Max [0, (TWTG q, r, p – ¼ * Max (((1 + K1) * AABP q, r, p), (AABP q, r, p + Q1)))] Where: TWTG = (( AVGTG q, r, p, i)/3)) * ¼ K1 = 5 % Q1 = 5 MW Under Generation: BPDAMT q, r, p= Max (0, RTSPP p) * Min (1, KP) * Max {0, {Min [((1 – K2) * ¼( AABPq, r, p)) , ¼( AABPq, r, p – Q2 )] – TWTG q, r, p}} Where: TWTG q, r, p = (( AVGTG q, r, p, i)/3)) * ¼ K2 = 5 % Q2 = 5 MW Base Point Deviation – Proposal B: GREDP Inputs

11. [ab1]Some of the cons seemed the same, maybe my notes weren’t good We might want to mention details here about IRR? With proposal B we can pull in the telemetered HSL and calculate if curtailed or not. Benefit would be implementing prior to when curtailment flag is ready in EMS. Once flag is ready and consumed by GREDP we could pull from current data set. Base Point Deviation –