Could we build a starship using current technology?

[Johnny1A.2]

Originally Posted by generic mook

Suppose you had limitless resources and political will, and you wanted to build a starship. Your goal is to maintain constant acceleration of 1g for a period of at least 1 year (long enough to travel to a distant station and recharge).
1/ Could we do this using existing technology?

The chances are approximately halfway between zero and nil.

One gee for 1 year, I mean that's well into relativistic territory. You're talking about more energy used by the starship than the entire Earth uses. We don't even have a theoretical idea of how to do such a thing. The closest dreamy SFnal concept would be the Bussard ramjet, and we certainly can't build one of those right now (and there's reason to think the concept itself is unworkable).

The most powerful real-world-proposed space drive I know of is Orion. You could use that, in theory, to send very large spacecraft to most of the planets of the Solar System in reasonable time, but it wouldn't even get into the neighborhood of one gee for a year.