My house has an outdated Zinsco electrical panel, which I know should be replaced, but hasn't been. Is it wasting electricity (and money)?

My wife believes that the outdated box is less efficient than a modern electrical panel and is therefore wasting electricity. I don't recall any electrician we've spoken to indicating that, but maybe she's right. Is it? I know the box is a problem, but is it a money-wasting problem?