There was an interesting observation at some day cares in Israel. When their day care closed, parents would drop everything to make sure they picked their kids up on time, but some would still be late. At some point, these day cares decided to start applying fines whenever the parents were late, and it completely backfired. Parents were suddenly always late and in large numbers, because parents felt guilty about making teachers stay late, and by adding a fine, they removed that guilt.
I view a carbon tax in the same way. It's an easy way for companies to continue with whatever their doing and they replace any guilt they may have with an easy payment. It certainly isn't going to solve much, because it removes any real chance of accountability. It is not a significant enough incentive for them to implement impactful change.
The free market may help create solutions, but it will not sustain them. Reversing climate change will not be a profitable endeavor in the short-term, and unfortunately market success is a greedy algorithm.
It's a complete contradiction that a free market could ensure conservation, since it relies entirety upon consumption, and market success is about who consumes the most.
Link to article about Israel day cares: http://freakonomics.com/2013/10/23/what-makes-people-do-what...