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gateway/knowledge/trading/strategies/miscellaneous/energy-spark-spread.md

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+---
+description: "Capture or hedge the gross margin of a gas-fired power plant by trading the spread between wholesale electricity prices and natural gas fuel costs, using electricity and gas futures in the ratio determined by the plant's heat rate."
+tags: [miscellaneous, energy, spread-trading, hedging, commodities]
+---
+
+# Energy — Spark Spread
+
+**Section**: 14.4 | **Asset Class**: Miscellaneous (Energy Commodities) | **Type**: Spread Trading / Hedging
+
+## Overview
+The spark spread is the difference between the wholesale price of electricity and the price of natural gas required to produce it. It measures the gross margin of a gas-fired power plant (excluding all other costs: operation, maintenance, capital, etc.). A spark spread position is built by taking a short position in electricity futures and a long position in natural gas futures, in the ratio determined by the plant's heat rate.
+
+## Construction / Mechanics
+
+**Heat rate** (fuel efficiency of the power plant):
+```
+H = Q_F / Q_E                    (516)
+```
+- `Q_F` = amount of fuel (natural gas) used, measured in MMBtu
+- `Q_E` = electricity produced, measured in MWh
+- `H` measured in MMBtu/MWh
+- MMBtu = 1,000,000 Btu; Btu ≈ 1,055 Joules
+
+**Spark spread** (in $/MWh):
+```
+S = P_E - H × P_F                (517)
+```
+- `P_E` = price of electricity ($/MWh)
+- `P_F` = price of natural gas ($/MMBtu)
+
+**Hedge ratio** for futures contracts:
+```
+h = H × F_E / F_F                (518)
+```
+- `F_E = 736 MWh` (standard electricity futures contract size)
+- `F_F = 10,000 MMBtu` (standard natural gas futures contract size)
+
+Since `h` is generally not a whole number, it is approximated as the ratio `h ≈ N_F / N_E` with the lowest possible whole-number denominator `N_E`. The hedge consists of buying `N_F` gas futures contracts for every `N_E` sold electricity futures contracts.
+
+## Return Profile
+- **Electricity producer (natural hedge)**: short electricity futures + long gas futures locks in a fixed spark spread, hedging against a compression of the gross margin
+- **Speculator / spread trader**: profits if the spark spread widens (electricity prices rise relative to gas prices) on a long spread position, or if it narrows on a short spread position
+- The strategy has no directional energy price exposure — only exposure to the relative price of electricity vs. natural gas
+
+## Key Parameters / Signals
+- **Heat rate `H`**: plant-specific efficiency; lower `H` = more efficient plant = higher spark spread for the same fuel cost
+- **Spark spread `S`**: core signal; compare to historical average or fair value based on plant operating costs
+- **Contract sizes `F_E`, `F_F`**: determine the achievable hedge ratio granularity
+- **Seasonal patterns**: electricity demand (and spark spread) exhibits strong seasonality driven by heating/cooling demand
+
+## Variations
+- **Dark spread**: same concept for coal-fired power plants (replaces natural gas with coal prices)
+- **Quark spread**: same concept for nuclear power plants
+- **Clean spark spread**: adjusts for carbon emission costs (CO2 allowance prices) in addition to fuel costs
+
+## Notes
+- The spark spread measures gross margin only; it does not account for fixed operating costs, maintenance, or capital expenditures
+- Basis risk exists between the price indexes referenced in futures contracts and the actual spot prices at the delivery location
+- Liquidity is concentrated in front-month contracts; longer-dated spark spread trades may have wide bid-ask spreads
+- Heat rates vary with plant load and ambient temperature; a single fixed `H` is an approximation
+- Regulatory risk: electricity markets are often heavily regulated; price caps and dispatch rules can affect realized spreads