A solar powered greenhouse that makes sense in Canada’s climate
Passive solar greenhouses are an idea whose time has come.
What is a passive solar greenhouse, you ask? And don’t they already use the sun’s energy?
Well yes, but with the traditional Dutch glass box greenhouse design all that heat leaves once the sun goes down. Because they are uninsulated, they don’t store any of that heat. As a result they need a lot of energy to heat the building at night, or they lose an excess heat out during the day.
Energy wise, they just don’t make sense for most of Canada.
The first thing they did was to get rid of the north-facing glass wall that loses heat and doesn’t bring in light. That north facing wall and the back half of the building was replaced with a roof and a thermally massive concrete wall and floor structure designed to keep the heat in, store heat captured from the sun and release it overnight.
On the front of the building, facing south is the only glass this greenhouse has – a large curved, glass wall. The roof has solar PV panels to generate electricity and it also has a solar thermal hot water system that heats an in-floor concrete heating system. It also has an annualized geo-solar system where hot air is collected from the ceiling and pumped underneath the building.
To find out more about this project read the whole story at the Green Energy Futures website.