The PV panels will last decades, but even chemically treated (a whole new environmental problem in itself) bamboo would not last that long, especially in a humid environment over a water filled canal.

Some people might cite how long railroad trusses last (many decades), but that is because they get regularly coated with creosote (obtained from burning coal) or other chemicals on a regular basis. Having observed such retreatment processes of a railroad bridge near a prior home, I know a LOT of the chemicals drip off the structure onto the surface below. In this case, the structure would be spanning many miles of the canal, so the surface that the potentially toxic chemicals are dripping into is water destined for farms (and possibly human drinking water in a country not known for good water treatment). Worse yet, the retreatment of the bamboo structure would also entail overspray onto the panels – PV panels are normally made as one unit – if even a small portion of the panel were to be shaded even a small amount (say from a small amount of overspray of creosote or even a seemingly “clear” chemical, the entire panel would decrease in efficiency).

Additionally, the metal ramework would surely be coming from pre-existing producers, who if located in India, would already be using the energy they are using and would still be using that energy if the solar framework were to be made of other materials.

The metal framing is most likely “second use” steel. Recycled from other uses such as automobiles. Some likely coming from the ship wrecking yards.

Bamboo is pretty incredible stuff. I’ve seen buildings significantly higher than ten stories being built with bamboo scaffolding. But I’d suspect each individual bamboo pole or timber is used only a few years.

My thought is that appropriate design and perhaps chemical treatment would allow bamboo to do much of the work that the photo suggests that metal trusses are being used for in the demonstration project being discussed.

India in particular has additional reason to look at this. Unlike the US where consumption of electrical power delivered by the various grids has leveled off over the last five years, Indian power companies famously come up short on delivering the power consumers and small businesses need. Using available capacity to process metals needs to be considered pretty carefully under those circumstances.

We should notice that this approach would parallel the synergy the scheme already offers in reducing evaporation from the water in the irrigation canals.

California has quite a lot of similar water canals, yet the water department was decidely unenthusiastic about this, claiming they’d rather put the panels on dry land. I presume they ran the numbers.