04.01.2021
A follow-up to the Cleantech Venture Day appearance, where the transparent solar glass was presented to investors focused on clean technology.
Coverage of the original pitch is collected on the Cleantech Venture Week page.
More coverage is collected under press; the technology itself is described on the project page.
Related material: the project, press coverage and the collaborators behind the technology.
Power generated on a greenhouse roof is usually consumed on site. Climate control, irrigation pumps, ventilation and supplementary lighting all draw during the same daylight hours when the glazing produces, so much of the output never touches the grid.
That self-consumption is what makes the economics work. Electricity used where it is generated is worth the retail price rather than the feed-in tariff, and it avoids both transmission losses and the connection queues that hold up ground-mounted projects.
Every square metre of greenhouse roof receives more solar energy than the crop beneath it can use. Photosynthesis draws mainly on the blue and red bands; a large part of the spectrum passes through and warms the structure without feeding anything. Semi-transparent photovoltaics work in that gap.
The design question is where to draw the line. Absorb too much and the plants notice; absorb too little and the electrical yield does not repay the glass. The answer differs by crop and by latitude, which is why installations are specified per project rather than sold as a single product.