Source: Tradingview.com (ERCOT North Spark Spread) In energy markets, spreads such as spark and dark (and their “clean” variants) reveal the economic incentives for power-plant dispatch. They also act as support or resistance levels for underlying fuels — especially natural gas. Spark Spread The spark spread measures the theoretical margin for a gas-fired generator. Formula: Spark Spread = Electricity Price − (Natural Gas Price × Heat Rate) Dark Spread The dark spread applie