Price Cannibalization (Solar/Wind)

Price cannibalization is the decline in realized market prices that occurs when additional generation from a technology depresses prices during the same periods in which that technology produces most strongly. It is a structural market effect seen most clearly with high shares of solar or wind.

The concept matters because it shows that adding more low-marginal-cost generation does not simply scale revenue in proportion to output. As penetration rises, the technology can erode its own capture price unless flexibility, transmission, or complementary demand grows alongside it.

Key Aspects of Price Cannibalization:

• Self-Reinforcing Price Effect: The more output concentrated in the same time window, the more likely prices are to weaken in that window. This is especially visible for solar around midday in high-penetration systems.
• Different by Technology and Market: Solar and wind show different cannibalization patterns because their production profiles differ. The severity also depends on interconnection, storage, demand flexibility, and market design.
• Capture Price Consequence: Cannibalization reduces the price actually realized by the technology causing the surplus. That makes average market price a poor proxy for future project revenue.
• Can Be Mitigated: Storage, hybrid plant design, stronger transmission, flexible demand, and geographic diversification can reduce cannibalization pressure. The problem is not purely a renewable issue, but a system-flexibility issue.
• Important for Long-Term Forecasting: Revenue models that ignore cannibalization often overstate future value for new renewable projects. It is one of the key structural adjustments required in high-renewable market analysis.