Solar tunnel dryer Typ "Hohenheim"

Energy self-sufficient drying:

Solar drying has been used to preserve food since time immemorial. Today, the use of solar energy is more topical than ever. The solar tunnel dryer type Hohenheim combines simple construction, use of regenerative energy and safe handling. It is particularly suitable for the production of high-quality products on farms. As a joint development of the Institute for Agricultural Engineering in the Tropics and Subtropics at the University of Hohenheim and the company INNOTECH, solar tunnel dryers of the Hohenheim type are in use in more than 110 countries

Effective preservation for fruits, vegetables, herbs, spices, or similar:

Preservation through adapted technology is the key to successful economic activity. While in the European Union only about five percent of marketable agricultural products spoil after harvest, in the regions of the tropics and subtropics it is up to seventy percent. Inadequate storage facilities and poorly developed infrastructure prevent smaller producers in particular from accessing the market. The seasonal surplus during the harvest cannot be sold, and only low prices are achieved on the regional market. An alternative is to process the crop into high-quality dry products. The harvest becomes storable products, the producer can offer his products on the market for longer. Transport costs are reduced, while the earnings from the additional work go directly to the producer. Stored produce brings regular earnings and less dependence on seasonal cultivation. The prerequisite is hygienic processing and production.

Simple technology with great benefits:

The simple construction allows the solar tunnel dryer to be quickly set up on site as well as transported. Fruits, vegetables, spices and medicinal plants can be dried without conversion. The sophisticated construction enables drying even under unfavourable weather conditions, an indispensable condition for professional use. Seasonal overproduction, oversized and undersized produce become valuable commodities. The users of the solar tunnel dryer are farms and families as well as aid organisations that present improved technology at demonstration plants. The dryer has also been used successfully by women's groups in developing countries, who use it to contribute to family incomes. Increasingly, it is also organic farms that are taking advantage of the ecological benefits of solar drying and producing high-quality dried products from controlled organic cultivation.


Technical data

  • Length: 18 m
  • Width: 2 m
  • Collector area: 16 m²
  • Drying area: 20 m²
  • Air flow rate: 400-1200 m³/h
  • Air temperature: 30- 80 °C
  • Electrical power: 20- 40 W
  • Fan drive: Solar panel
  • Construction: approx. 1 Day
  • Scope of delivery: all components incl. replacement foil
  • Thermal energy generation from solar radiation: up to 60 kWh/ day (approx. 15 kg Firewood)