Re: Energy generation from waste heat.
Their homepage is here. I haven't had time to check it out yet, but typically the effectiveness of any method of generating power from heat depends on part of the system being kept cool. The efficiency often depends on the temperature gradient you are working across. If these things are mounted on something like muffler, the outside would have to be cooled some way to make them work at all, and the natural radiation cooling doesn't seem like it would do the job.