History

Most greenhouses in Canada are heated with either natural gas or liquid petroleum gas. Heating constitutes a major cost in greenhouse production. The recent increases in the price of natural gas have caused greenhouse growers to seek energy efficient technologies to reduce their operating costs. Solar energy is the most cost effective means for greenhouse heating.

Northwestern Ontario winters are cold, but sunny. Indeed, the ‘Sunshine Capital of Ontario’ in the winter. During the months of December, January and February, Thunder Bay gets an average of 340 hours. This is only marginally less than Winnipeg. This significant amount of solar energy provides opportunities for northern greenhouse growers to reduce or even eliminate supplementary heating requirements in operating greenhouses during winter or early spring.
The amount of solar energy indicated above is sufficient to maintain the desirable greenhouse temperatures during daytime. However, the challenge is to maintain the greenhouse temperature after sunset with little supplemental heating. The objective of my prototype was to evaluate the thermal performance of a solar energy greenhouse that stores solar energy during the day for heating at night.
In middle and northern China, simple, inexpensive and energy conserving solar energy greenhouses have been used to produce vegetables in winter, late fall and early spring since the 1980s’ (FAO 1994). These are regions where temperatures are similar to ours, i.e. in the -5˚ to -32˚ Celsius range in the winter. It is also a part of the world where energy supplies are both scarce as well as costly and with many people to feed. There are more vegetables produced there in greenhouses than on fields and are supplied year-round. Some 170,000 acres are covered by greenhouses in China.

From my research, the most significant work being done in Canada has centered in Manitoba with testing by the Biosystems Engineering Department of the University of Manitoba at a solar greenhouse in Elie. After completing my preliminary research, I drove to Manitoba in June 2008 to see for myself some of the work undertaken in that region. I met with Dr. Chong Zhang, Head of Biosystems Engineering at the University of Manitoba and principal researcher on the project. I showed him the preliminary architectural drawings of my proposed greenhouse. While offering several excellent recommendations, for the most part he considered my plans as entirely workable. I would later incorporate, modify and extend some of their features in my own unique design.
The next year was spent modifying drawings with my brother Ray who is an architectural technologist. I consulted several times with Bob Payne who would be the lead-hand in construction, electrical and plumbing. I met with Arjen DeBruin my greenhouse consultant to get somewhat up to speed on a complex business. And of course financial number crunching, cost analysis and funding. Finally we began to break ground in June of 2009.