Negative pricing
In economics, negative pricing can occur when demand for a product drops or supply increases to an extent that owners or suppliers are prepared to pay others to accept it, in effect setting the price to a negative number. This can happen because it costs money to transport, store, and dispose of a product even when there is little demand to buy it, or because halting production would be more expensive than selling at a negative price.
Negative prices are usual for waste such as garbage and nuclear waste. For example, a nuclear power plant may "sell" radioactive waste to a processing facility for a negative price; in other words, the power plant is paying the processing facility to take the unwanted radioactive waste. The phenomenon can also occur in energy prices, including electricity prices, natural gas prices, and oil prices.