From solar thermal systems to transformers and heat pumps: energy technology describes a broad field. And an even wider range of applications for gaskets. Issues such as strong temperature fluctuations, extreme forces and contact with different media are one thing. Loss of efficiency due to energy losses is another. The requirements are correspondingly extensive: Low gas permeability, chemical resistance to media such as water antifreeze or refrigerants in heat pumps and high thermal flexibility are basic requirements.