Energy GPS  CAISO Battery Dashboard - 2025-10-01
Figure 1 | Price Responsiveness - Battery Operations and RTM Price
Figure 2 | TBNth RTM Arbitrage Values ($/MWh)
Last Yr Month Avg Prev Month Avg Curr MTD Avg Past Week Dly Delta Dly v. Curr MTD Dly v. Prev Month YoY
Region Oct-24 Sep-25 Oct-25 9/25 9/26 9/27 9/28 9/29 9/30 10/1
NP15
TB1st 79.55 57.19 48.31 36.2 28.58 23.52 23.08 25.49 54.46 48.31 (6.15) 0 (8.88) (31.24)
TB2nd 41.55 31.09 20.32 21.39 20.15 14.89 14.03 10.33 23.79 20.32 (3.46) 0 (10.77) (21.23)
TB3rd 27.79 22.14 16.79 16.24 15.17 10.85 10.93 7.4 16.92 16.79 (.13) 0 (5.35) (11)
TB4th 20.33 17.06 14.12 11.85 12.7 9.65 9.15 5.62 12.58 14.12 +1.55 0 (2.94) (6.2)
TB4 Arbitrage 41.69 31.24 24.65 20.87 18.58 14.12 13.98 11.68 25.96 24.65 (1.3) 0 (6.59) (17.03)
Gen-Weighted Arbitrage 28.42 22.51 21.55 12.73 14.65 13.04 10.9 (6.78) 11.12 21.55 +10.44 0 (.96) (6.87)
SP15
TB1st 62.38 50.36 92.19 41.73 41.91 25.51 56.44 35.51 89.77 92.19 +2.42 0 +41.83 +29.81
TB2nd 43.02 37.63 62.2 30.64 32.83 17.39 47.53 25.38 73.5 62.2 (11.3) 0 +24.57 +19.18
TB3rd 35.59 31.58 57.31 27.2 28.58 13.64 44.82 20.94 63.4 57.31 (6.09) 0 +25.74 +21.72
TB4th 30.44 27.88 54.48 24.78 26.44 12.03 42.84 19.05 54.8 54.48 (.32) 0 +26.6 +24.04
TB4 Arbitrage 41.88 36.25 66.24 30.53 31.69 16.59 47.47 24.64 69.47 66.24 (3.23) 0 +29.99 +24.36
Gen-Weighted Arbitrage 31.7 24.85 56.37 22.37 20.5 13.63 39.04 17.94 50.93 56.37 +5.44 0 +31.51 +24.66

* TBNth value measures the arbitrage value of the Nth best pair of buying and selling hours in a day. For RTM, one hour of buying or selling may take place over 12 non-continuous, 5-minute intervals. For example, an RTM TB2nd value of $20/MWh means that energy bought in the 13th-24th lowest priced 5-minute intervals can be sold in the 13th-24th highest priced intervals for $20/MWh more than the buying price. Round-trip efficiency is calculated in the TBNth by dividing the buy price by 0.87. For the TB4 Arbitrage, efficiency is calculated using partial prices from the fifth lowest hour.
** The generation weighted arbitrage is a weighted average of the SP15 and NP15 real-time prices using the charge and discharge pattern of the CAISO fleet each day to estimate how much of the TB4 arbitrage an ‘average’ battery is capturing. It is possible for this average to be higher than the TB4 arbitrage, such as when a battery captures the TB1st by charging during the highest priced hour and charging at the lowest price hour and then sits idle for the rest of the day.

Figure 3 | Ancillary Prices ($/MW)
Last Yr Month Avg Prev Month Avg Curr MTD Avg Past Week Dly Delta Dly v. Curr MTD Dly v. Prev Month YoY
Region Oct-24 Sep-25 Oct-25 9/25 9/26 9/27 9/28 9/29 9/30 10/1
CAISO
RegDown 4.93 4.16 4.42 3.82 4.4 4.46 4.88 4.09 4.37 4.42 +.05 0 +.26 (.51)
RegUp 2.29 2.08 1.86 1.72 1.46 1.81 2.11 2.23 2.29 1.86 (.43) 0 (.22) (.43)
Spin 1.58 1.01 .66 .69 .61 .72 .68 .69 .67 .66 (.01) 0 (.35) (.93)
CAISO + NP26
RegDown 6.58 5.34 4.76 5.23 4.77 4.73 5.29 4.66 4.81 4.76 (.04) 0 (.58) (1.82)
RegUp 5.55 3.67 3.23 2.89 2.72 2.87 3.1 3.9 3.57 3.23 (.33) 0 (.44) (2.31)
Spin 3.69 1.66 .97 .83 .94 .86 .8 .79 .8 .97 +.17 0 (.69) (2.72)
CAISO + SP26
RegDown 5 4.19 4.49 3.82 4.44 4.52 4.89 4.16 4.92 4.49 (.42) 0 +.31 (.51)
RegUp 2.35 2.15 1.88 1.72 1.46 1.84 2.43 2.24 2.34 1.88 (.46) 0 (.27) (.47)
Spin 1.58 1.01 .66 .69 .61 .72 .68 .69 .67 .66 (.01) 0 (.36) (.93)
Figure 4 | Ancillary YoY 7 Day Rolling Average Prices ($/MW)
Figure 5 | IFM AS Awards
Last Yr Month Avg Prev Month Avg Curr MTD Avg Past Week Dly Delta Dly v. Curr MTD Dly v. Prev Month YoY
Region Sep-24 Aug-25 Sep-25 9/24 9/25 9/26 9/27 9/28 9/29 9/30
NonSpin Awards 142.57 189.97 205.67 166.50 187.42 202.29 191.21 207.25 109.83 144.88 +35.04 -60.80 -45.09 +63.10
Spin Awards 258.23 325.58 278.04 180.75 261.08 233.71 222.58 189.46 358.83 251.29 -107.54 -26.75 -74.29 +19.81
RegUp Awards 481.03 419.00 432.81 467.00 398.88 377.63 446.38 450.04 448.33 367.08 -81.25 -65.73 -51.92 -48.22
RegDown Awards -655.79 -742.34 -814.65 -903.96 -841.88 -812.67 -959.71 -916.33 -958.92 -844.08 +114.83 -29.44 -101.74 -158.85
Figure 6 | Comparison of Value Streams ($/kW-M)
Last Yr Month Avg Prev Month Avg Curr MTD Avg Past Week Dly Delta Dly v. Curr MTD Dly v. Prev Month YoY
Region Oct-24 Sep-25 Oct-25 9/25 9/26 9/27 9/28 9/29 9/30 10/1
NP15
CAISO + Region Total Regulation 8.86 6.58 5.84 5.92 5.47 5.54 6.12 6.25 6.11 5.84 (.28) 0 (.74) (3.02)
Energy Balanced Regulation 7.25 5.26 4.58 4.88 4.43 4.53 5.03 4.98 4.92 4.58 (.34) 0 (.67) (2.67)
DAM Energy Arb 3.75 2.26 .52 1.02 1.76 1.78 1.25 .44 .77 .52 (.25) 0 (1.74) (3.23)
RTM Energy Arb 5.17 3.75 3.06 2.5 2.23 1.69 1.68 1.4 3.12 3.06 (.06) 0 (.69) (2.11)
SP15
CAISO + Region Total Regulation 5.37 4.63 4.66 4.04 4.3 4.64 5.35 4.67 5.3 4.66 (.64) 0 +.03 (.71)
Energy Balanced Regulation 4.37 3.65 3.76 3.22 3.61 3.78 4.57 3.84 4.56 3.76 (.81) 0 +.11 (.61)
DAM Energy Arb 5.13 3.37 4.65 3.58 3.38 2.53 4.2 2.5 4.42 4.65 +.23 0 +1.27 (.48)
RTM Energy Arb 5.19 4.35 8.21 3.66 3.8 1.99 5.7 2.96 8.34 8.21 (.12) 0 +3.86 +3.02
Figure 7 | Hourly Bidding Behavior


* CAISO provides data on the number of megawatts from batteries bidding to charge or discharge in each 15-minute interval in the real-time market within a certain price range. The above weighted bids are calculated by multiplying the total number of MWs in each range by the lowest price of that range, summing all the products for that time interval, and dividing by the total number of megawatts for the time interval. Exact prices within the range and how many MWs cleared at a given price are unknown so it is not a metric that can be directly compared to the real-time price but does allow for monitoring average bid price over time. Higher values represent a willingness to charge energy from the grid, lower values represent a willingness to discharge energy into the grid.”