Compressed air is an expensive energy medium – the energy needed to compress the air is significant. “10 to 30 % of the energy costs of a company that works with compressed air are spent just on creating the energy medium,” says Portwich. The possible uses of compressed air are many and mostly indispensable. For example, industrial systems use compressed air for pneumatic drive systems and transport of bulk materials or fluids, since systems powered by compressed air are characterized by speed and precision. The heat energy that arises when air is compressed usually remains unused – money is vanishing into thin air, so to speak. Energy consultant Michael Portwich recognized this problem in his everyday work and, as an engineer, is used to not only recognizing problems, but also solving them. The obvious solution would be to simply make further use of the heat that is produced. Portwich went a step further, taking the entire process apart and reconceiving it from the ground up. The result was the idea for the first combined heat and compressed air co-generation system. “This isn’t rocket science – just thinking solutions through to their logical conclusion,” says Michael Portwich modestly, describing his company “altAIRnative.” But the idea behind the company is actually revolutionary. Unlike in normal air compression, heat is not the waste product. It works the other way around: When heat is generated by the co-generation system, compressed air is the byproduct. “Customers get compressed air for free, so to speak,” says Portwich, summarizing the economic advantage of the co-generation system. But that’s not all. Portwich wanted to go one step further and conceived of an alternative method for driving the systems as well, which reduces CO2 significantly. Instead of using electricity, the co-generation system generates heat with a gas-driven combustion engine, at a temperature from 90 to 108 °C, which is available for industrial use. A highly efficient screw compressor is driven via a coupling at the same time. The air compressed to up to 13 bar results more or less as a byproduct. Since this method of air compression does not require electricity, there are no high electricity costs. “I’m known as a lateral thinker, and when I’m sold on an idea, I look for allies,” says Portwich, managing director, describing the start of the process of establishing his company. He found one such ally right at the start in his second managing director, Jens Tiede, a mechanical engineer.