During my time at VEIC, we rebuilt this site from the ground up. It's built on a large variety of systems, from the .NET CMS Orchard to several versions of Angular.
The audience is wide and varied, ranging from consumers looking for information on energy efficient appliances, through contractors looking for information, up to legislators looking for details on the organization. As such, the information architeture was of primary importance. The end result is a friendly and usable site for most audiences.