Let There Be Light

Solar Glass!! Stop the Bus!

At the HFF conference, in Melbourne last month, there were a number of thought-provoking subjects presented and discussed.    Just when I thought I would get a rest another subject caught my attention and got me thinking.   This article focuses on one aspect within the presentation by the CEO of Powerplants, Carl Van Loon, whose overall topic was Greenhouse Coverings.

Solar Glass:

Earlier the same day another presentation described technology ‘at warp speed’, in terms of how we currently discuss new technology advances in months, not years.   Later Carl mentioned the potential of Solar Glass that allows 70% of PAR light into greenhouses, at the same time producing electricity- this made me sit up and listen, and what some may say is dangerous, think!!  Just when you think you may have the ideal recipe how to build the perfect greenhouse, another pearl of wisdom comes along.

Be very careful, when considering building new greenhouses, to consider the consequence of fast technological change, especially when technology is rapidly superseded.  Large capital investments have to be made when building greenhouses, and since technology is changing so fast it is very important to ask a number of questions.  None of which are stupid.  Before I become over excited, I want to be considered in the approach of possibly building a greenhouse with Solar Glass.  The idea that we could grow crops and produce electricity using Solar Glass sounds incredible, but I certainly have some reservations that need to be addressed. 

Immediately I thought could electricity produced from a Solar Glass greenhouse support a heating and cooling system as well as supplementary lighting?  However, this throws up a set of new questions I simply don’t have the answers to, but I would definitely be using experts to find out. 

Would enough electricity be produced by a Solar Glass greenhouse, during the winter, to maintain a heating system and supplementary lighting?   Reading a statement from a Solar Glass suppliers website it describes being able to produce 1kw of energy from 10m2 of glass assuming a sunny aspect.  That is too vague.   I would require a great deal more information regarding what range of light intensity and the length of time it takes to produce each KW.  I would use this data to understand how much energy is required to run supplementary lighting on the darkest day of the year and how much energy you would be able to capture/produce on the darkest day of the year.  During Summer, with high ambient temperatures could enough electricity be produced to cool a greenhouse using current cooling systems available?

 Growing Questions;

1. How much energy can I produce for different times of the year per m2?

2. How much energy will I need to operate a heating system?

3. How much energy will I need to operate a supplementary lighting system?

4. How much energy will I need to operate a cooling system per m2?

5. Would I need to store my energy and how? (Would location determine how much storage is needed)

6. Would I need added energy from a different source?

7. How important is location?

Financial Considerations;

1. Capital investment, what is the cost of installation vs traditional systems?

2. How long will the estimated return on investment take?

3. What is the life span of the ‘Solar Glass’?

These are just a few of the questions that I have considered.  I am sure you will have many more as well.   I won’t be rushing to advise growers to build with Solar Glass any time soon but it is food for thought, and with technology changing so rapidly it might not be that far into the future concepts such as ‘Solar Glass Greenhouses’ using only renewable energy become a reality.   

I appreciate your comments.  Please feel free to comment below or on the grower2grower Facebook page:

https://www.facebook.com/StefanGrower2grower/

Article Written by Stefan Vogrincic, Consultant, Grower2Grower