1.   But some of the more obscure contracts on items such as emissions credits and weather derivatives may be more difficult to unload.

2.   For example, it included lines with details about its coal, metals and weather derivatives.

3.   In the case of weather derivatives, investors are betting whether the sun will shine.

4.   Power companies use weather derivatives to hedge against lower sales caused by consumers turning off the heat when the temperature is warm.

5.   Still, others see a promising future in weather derivatives, and not just selling them to energy companies.

6.   Aquila trades electricity, natural gas, weather derivatives, oil and oil products in the United States and Europe.