13 - Tropical Greenhouse at Ruswil, Switzerland
Project name
Waste Heat Reuse in a Tropical Greenhouse, Ruswil, Switzerland
Aquaculture, tilapia, tropical fruit production, waste heat utilisation, tropical Greenhouse
Start of the project
End of the project
Contact person
Johannes Heeb
seecon international gmbh
Phone +41 79 366 68 50
Email: This e-mail address is being protected from spam bots, you need JavaScript enabled to view it
Short project description/ project function
The background for the project is a legislation that requires that 60% of the industrial waste heat must be reused to minimise environmental impacts. In 1997 the idea was born to use the waste heat from a gas compressing station in a greenhouse with tropical climate. The main reasons to choose a tropical climate are:
  • substitution of tropical fruit import to Switzerland
  • such greenhouses needs less space than conventional ones.
The second point is important for the careful integration into the landscape. After a preparation phase of two years, a first pilot greenhouse was built. It started operation in spring 1999 for a pilot phase of three years. The pilot greenhouse covers an area of about 1'500 m2 divided in two equal parts. An aquaculture is also integrated. The main tasks of the pilot phase are, to show that the concept is working and to find the relevant questions and answers for the operation of greenhouses of that kind on a larger scale.
Summary of experiences
The main question behind this project is, whether the feasibility of the project idea can be proven on both the ecological and economical level. This means to run a tropical greenhouse under the given local condition using a conventional greenhouse type.

Papayas (Carica papaya), Bananas (Musa acuminata), Barbados Cherry (Malpighia punicifolia), Carambole (Averrhoa carambola) and Guava (Psidium guajava) are the most successful fruits of the greenhouse.

It was also an aim to create and close nutrient and water cycles as much as possible within the greenhouse as well as on local level. Experiences show that the water need can be covered with rainwater which is collected from the greenhouse roof, except for some special few cases where tap water containing lime stone was needed. On the nutrient level, the only input into the greenhouse system is fish fodder. The fish water containing surplus nutrients from the fish basins is used to irrigate and fertilise the plants of the greenhouse.

Studies shows that the fruits produced in the greenhouse are more ecologically sound and better in taste then imported fruits. The business experiences shows that profitability is as high as with comparable farm products.
Project benefits
The project creates a win-win situation. For the gas compressing station it is a way to reuse the waste heat. The greenhouse generates income possibilities for the nearby farmers by producing ecologically beneficial tropical fruits and fishes (Tilapia) which have a great demand on the local market. The greenhouse also is a platform for public awareness on Ecological Engineering
Project level
Pilot project
Financial scale
USD 600'000 (CHF1'000'000.- ) construction costs
Environmental conditions
Temperate climate
640m above sea level
Description of special local conditions
The project is integrated in the hilly area of the Swiss prealpin zone.
Why this is ecological engineering
The system is inspired by Chinese ideas of integrated farming and runs entirely on waste heat and electricity generated by using the waste heat.
Last Updated ( Tuesday, 19 August 2008 )