I loved the idea of covering the current water channels with solar panels to generate electricity while reducing evaporation of the circulating water. It is a simple and brilliant idea at the same time, which has been proposed by the University of California.
The idea has appeared in California and is already being used in India and elsewhere. In California they have more than 6,000 kilometers of water channels to take it from the northern mountains to the southern prairies, where are grown all kinds of agricultural products, in addition to tens of millions of people living.
Covering those waterways with solar panels could yield 13 gigawatts of power, which is half of what the state of California needs to meet its future green goals.
But it is also that if the canals are covered, the evaporation of the water that passes through them is reduced (around 2%) and that can mean the staggering figure according to the UC of almost 300,000 million liters.
I see no more than advantages to this idea, since placing the water panels on the water channel avoids having to use land that can be used for other purposes. In addition, when water circulates through the channel and under the panels, they are cooled a few degrees (around 10ºC) with respect to the ambient temperature and therefore generate 3% more energy.
Its only drawback is that it is somewhat more expensive to place the solar panels on a canal than on dry land, but I think the collateral advantages more than make up for it.
This idea that emerged in the USA is transferable to any environment or country. In Spain we have a few channels that could be used to generate additional electricity, and in other places like India they have already started to do so.
Today solar energy is already the cheapest way of getting energy, and I think we should make the most of the physical space resources we have, and use our good farmland as efficiently as possible.
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