The none option acts as a static option in your choice study, often taking on the role of how much utility the choice of nothing would be, as opposed to choosing an option you presented a respondent. Typically it's kind of difficult to get something from the specific value of a none option, since just like the other utilities, it's relative to your study. In general, a large, negative utility would indicate that there are a lot of level combinations you could put together that would be better than the none alternative. Similarly, a large, positive utility for the none means you would need to put together a "good" combination of levels to create a product the respondent likes in order to be preferred to the none choice.
The none utility, like normal conjoint utilities, is probably best understood by using a market simulator to simulate configured products and predict how the utilities values would translate into choices respondents would make.