Minnesota lawmakers may have reached the limit on what they can do to protect consumers from the propane shortages and price spikes seen this past winter. The Legislature swiftly approved $20-million in emergency heating aid in February. But there was talk then about doing more to address issues that led to the problem. But solutions have been elusive. The bill that’s gotten the most hearings would protect consumers, but wouldn’t do much to avoid shortages. Two other bills have made some progress, but one simply calls for a study and the other’s future is doubtful.