Extremely polished, incredible game. This should absolutely be winner.
The limitation is used exceptionally well. I've seen a lot of games this jam have rules change from level to level, but this was, without a question, my favorite game that opted to go that route.
Map design is excellent. The conveyor belt brings a really interesting dimension to levels: it's both an escape tool since it boosts your speed, and also a tool to carry coal up from the bottom of the map (where there's more coal, naturally). Both Freezing and Starving added interesting variables to the equation on how to best solve the level.
The final level is brilliant: having Cobb get his senses back with each battery pickup makes for a very tense experience. I will say that it is VERY difficult -- way more so than the rest of the game. When it wasn't over when I placed the 4th battery and I (presumably) had to dunk him into the fire I screamed I was so mad arrrghhhh >:(((( I eventually got the ending but wow what a challenge.
Extremely well done. One of the best jam games I've played ever.