Super Ecotunnels

Tobacco Curing Ecotunnels

Our tunnels are fairly unique on the market due to low power consumption, low coal consumption and, we run our curer according to the Zimbabwe Tobacco Handbook using traditional curing techniques recommended for a long low barn as opposed to a chongololo. The reason for this is that in our experience, a four-tier long low gives you the best quality and leaf weights compared with any other curer. This means that we start off by curing the first third of the crop with a wet bulb temperature of 35°C and work our way up gradually to 38 °C WB on strips. This will give you your best wilt, quickest colouring time, best coal consumption and your best leaf quality and give you a more orange style, which is favourable in today’s market. If these parameters are maintained correctly it naturally prevents barn rot without any need for chemical control. We have infinite variation in heat, airflow and humidity control which as with primary colours can achieve any colour in the colour spectrum. 


This is true for curing where you can within reason achieve any combination within the tunnel. This is particularly useful when reaping over different crops where you have mixed reaping styles within the system. Our building designs require you to lay your footings 600mm below ground level. Other than the foundations the entire building including the plenum is all above ground, which greatly reduces your building costs and eliminates any chance of damp in wet seasons.

Tobacco Curing Ecotunnels Roc Systems Zimbabwe
Tobacco Curing Ecotunnels Roc Systems Zimbabwe

Our plenum is shallow, which keeps your building height to a minimum while aiding in a rapid response to any curing changes made. Our tunnels are designed with the Sunday Holding Bay on the eastern side – the full length of the tunnel. This is designed to gradually accumulate tobacco throughout the week, allowing you to feed the tunnel consistently for seven days a week while only reaping for six days a week. In other words, you generally reap an extra three trolleys a day, which is the first to go in the following morning, giving you an input of consistent ripeness tobacco preventing you having green Monday’s tobacco going in behind Saturday’s coloured tobacco.


All our tunnels come with triple traverses for moving trollies inside the tunnel and a single traverse, which is a mobile weighbridge for moving all green tobacco into the tunnel and conditioned tobacco out. Our ceilings are fitted using steel wire through the correx and tensioned with wire strainers thus eliminating the need for kilometres of brandering and carpenter costs. Our tunnels contain minimal amounts of organic material to limit weathering and to ensure longevity.


Our heat exchangers have a low maintenance requirement run at temperatures well below the steels limit and are painted with a heatproof paint capable of 50% higher temperatures than the steel will ever reach. They run in a partial vacuum which eliminates any chance of soot or gas leaking, which is traditionally found with dry heat exchangers. They are made with 3mm mild steel plate which can be easily repaired by the farmer in the event of any failure. Our extra large Heat Exchanger area, which is achieved by the large steel surface area and the surrounding brickwork and false roof, all come together to facilitate our high efficiencies and are evident by the fact that our galvanised chimneys run well below 100°C.


Trolleys a day1418222530
Reaping Trailers22334
Pockets cement880967114012941454
Average KW current drawn9.5111313

Super Eco Tunnel

Super Eco Tunnel Illustration Roc Systems
Dry Bulb/Wet Bulb Temperatures during the curing process in the Super Eco Tunnel

Advantages of our Super Eco Tunnel cure include:

  • Gentle cure
  • All curing takes place inside
  • Up to 20% more redundancy in power.
  • More versatile i.e. one style of curing will cover more leaf styles
  • Capable of a 9-day cure without leaf weight loss
  • The same 3 simple controls – Dry bulb temperature; Wet bulb temperature; Fan speed.

Existing tunnels can be upgraded to 15% more output for approximately 7% of the original price quote i.e. double the value for money compared to the original capital expenditure. Contact us now for a detailed quote.