Besides the embargo there are three challenges for the Cubans. The low price of oil, new opportunities in Mexico's waters and their failure to date.

Jorge Piñon

I am not an alarmist but for the first time in a long time I am really worried, you have a number of cumulative effects taking place that can not be solved with band-aids. We are talking about major structural investments in the billions of dollars that could take years to solve this problem.

Cuba has been able to produce a surplus of gasoline and jet fuel, which it can export to the international market to generate hard currency, it would not have that luxury once it has to pay hard cash for the crude oil.

This summer they are trying to insure the electric grid does not crash, and longer term, that they can handle increased demand from tourism and small business.

There does not seem to have been a cutback in crude oil and or petroleum products deliveries by Venezuela to Cuba, according to marine traffic reports, they may be expecting one in the future, building inventories or simply trying to save money or trying to insure there are no blackouts for residents as electricity demand increases.