With pressure on to reduce demand on energy resources be they bioenergy or fossil fuels, there is a need to take advantage of the most efficient types of tobacco curing systems.

The continuous curing system in the form of either the cascade or tunnel is by far the most efficient system in use in Zimbabwe. Tunnels are slightly more efficient than cascades. Preference is being shown for the tunnels. A tunnel system will use approximately 25-30% of the energy used in a conventional barn.

To further reduce the energy demand of tunnels, provision can be made to use some solar energy. The additional cost of using the solar energy is quickly paid for in fuel savings.

Tunnels have been in use for nearly 50 years. However in the last 18 years constant improvements have been made that now make the tunnel a very sought after system. Improvements have been in the form of better understanding and control of the units as well as physical improvements.

As the percentage of tobacco cured through tunnels increases so the total energy used in curing will reduce. As the energy demand drops it will become easier to supply the demand from sustainable sources.