Solar Greenhouse Design

All greenhouses use the power of the sun. But we are interested in designs that use the sun more efficiently to extend the growing season longer than the typical greenhouse.

“PassivGreenHaus”

This is an example of a “solar” greenhouse that we are experimenting with in Vancouver.

The design incorporates several elements that are different than a standard greenhouse:

Glazing (glass) is at an angle that is optimized to collect sunlight during the winter months.
The inside rear wall is at an angle optimized to reflect sunlight onto crops during the winter months (and painted to improve reflection).
Only the one wall has glazing. The other walls are all insulated to help keep heat in the greenhouse.
There is thermal storage (water barrels) to help hold heat in the greenhouse.

The graph above shows temperature data from February 2021. As you can see the greenhouse had day time temperatures that were as much as 20C above outside temperatures. Minimum temperatures (overnight) were 1 to 4 degrees above outside temperatures and fell below freezing.
Since these temperatures were recorded we have improved sealing of the envelope and added more thermal storage. New data coming soon.

2022 November Data

The data above was recorded after we added additional thermal storage (water barrels) and a “shutter” that we use to cover the glazing at night. There were also some improvements on sealing.
The daytime max temperature in the greenhouse stayed above 5 C. On sunny days the temperature was above 20C even when the outside temperature was below 10C.

At night the greenhouse stayed above 1 C even when the outside temperature was below -5C.

We can help you design and build an energy efficient greenhouses to extend your growing season.To find out more contact us through VREC Solar at 778-869-8333

main@aldercoast.ca