That's good enough reason not to use them. I'm trying to incorporate a little bit of 12 or 24V solar/wind power in my house. I've been designing systems for the past 5 years (www.otherpower.com my systems are less crude than theirs, but it's the same basic idea.) I'm just trying to find some type of receptacles/fuses rated for DC. I've found compact fluorescent bulbs for 12VDC with a Medium Edison base. I would never use a NEMA receptacle of any kind on my system just because I don't want to plug the wrong thing in the wrong plug. I am trying to shy away from cigarette lighter plugs.